VO Fresh

Changing-Look AGN from DESI. V.

2026-08-26T09:10:23Z

Description: We present a systematic search for changing-look (CL) quasars at high redshift z>0.9 by crossmatching the spectroscopic data sets from the Dark Energy Spectroscopic Instrument Data Release 1 and Sloan Digital Sky Survey Data Release 18. We identify 97 CL quasars showing significant variability in high-ionization broad emission lines, including 45 turn-on and 52 turn-off events, corresponding to a detection rate of ~0.042%. The low rate relative to low-ionization CL quasar searches is likely due to selection and physical effects in high-ionization lines. Based on the CL quasar sample, we find that CL quasars generally exhibit lower accretion rates compared to typical quasars, with average Eddington ratios of log{lambda}_Edd_~-1.14 in the bright state and ~-1.39 in the dim state, compared to ~-0.65 for typical quasars. Furthermore, while high-ionization lines in CL quasars follow the Baldwin effect on a population level, some sources can display inverse Baldwin trends. In addition, we find a positive correlation between the variability in high-ionization lines (e.g., MgII, CIII]) and the change in bolometric luminosity. We also estimate a characteristic rest-frame timescale of ~3yr for CL transitions, with no significant difference between turn-on and turn-off cases. Taken as a whole, these findings support an accretion-driven origin of the CL phenomenon, and provide new insights into the variability of high-ionization emission lines.
Author(s): Chen Z.-Q.; Jin J.-J.; Guo W.-J.; Sun S.-X.; Pan Z.-W.; Liu C.-X.,Cheng H.-Q.; Hu J.-W.; Sheng Z.-F.; Zou Hu; Chen Z.-B.; Zheng Qi,Yuan Q.-R.
IVOA id: ivo://cds.vizier/j/apjs/282/28

OzDES DR2 redshift catalogue

2026-08-26T07:07:10Z

Description: We present a description of the Australian Dark Energy Survey (OzDES) and summarize the results from its 6 years of operations. Using the 2dF fibre positioner and AAOmega spectrograph on the 3.9-m Anglo-Australian Telescope, OzDES has monitored 771 active galactic nuclei, classified hundreds of supernovae, and obtained redshifts for thousands of galaxies that hosted a transient within the 10 deep fields of the Dark Energy Survey. We also present the second OzDES data release, containing the redshifts of almost 30 000 sources, some as faint as r_AB_=24mag, and 375 000 individual spectra. These data, in combination with the time-series photometry from the Dark Energy Survey, will be used to measure the expansion history of the Universe out to z~1.2 and the masses of hundreds of black holes out to z~4. OzDES is a template for future surveys that combine simultaneous monitoring of targets with wide-field imaging cameras and wide-field multi-object spectrographs.
Author(s): Lidman C.; Tucker B.E.; Davis T.M.; Uddin S.A.; Asorey J.; Bolejko K.,Brout D.; Calcino J.; Carollo D.; Carr A.; Childress M.; Hoormann J.K.,Foley R.J.; Galbany L.; Glazebrook K.; Hinton S.R.; Kessler R.; Kim A.G.,King A.; Kremin A.; Kuehn K.; Lagattuta D.; Lewis G.F.; Macaulay E.,Malik U.; March M.; Martini P.; Moller A.; Mudd D.; Nichol R.C.,Panther F.; Parkinson D.; Pursiainen M.; Sako M.; Swann E.; Scalzo R.,Scolnic D.; Sharp R.; Smith M.; Sommer N.E.; Sullivan M.; Webb S.,Wiseman P.; Yu Z.; Yuan F.; Zhang B.; Abbott T.M.C.; Aguena M.; Allam S.,Annis J.; Avila S.; Bertin E.; Bhargava S.; Brooks D.; Carnero Rosell A.,Carrasco Kind M.; Carretero J.; Castander F.J.; Costanzi M.,da Costa L.N.; De Vicente J.; Doel P.; Eifler T.F.; Everett S.,Fosalba P.; Frieman J.; Garcia-Bellido J.; Gaztanaga E.; Gruen D.,Gruendl R.A.; Gschwend J.; Gutierrez G.; Hartley W.G.; Hollowood D.L.,Honscheid K.; James D.J.; Kuropatkin N.; Li T.S.; Lima M.; Lin H.,Maia M.A.G.; Marshall J.L.; Melchior P.; Menanteau F.; Miquel R.,Palmese A.; Paz-Chinchon F.; Plazas A.A.; Roodman A.; Rykoff E.S.,Sanchez E.; Santiago B.; Scarpine V.; Schubnell M.; Serrano S.,Sevilla-Noarbe I.; Suchyta E.; Swanson M.E.C.; Tarle G.; Tucker D.L.,Varga T.N.; Walker A.R.; Wester W.; Wilkinson R.D.; DES Collaboration
IVOA id: ivo://cds.vizier/j/mnras/496/19

Ffundamental plane of the radio-SFR relation

2026-08-26T06:33:25Z

Description: Radio continuum emission has the potential to be an extinction-free tracer of star formation. However, the relation between radio continuum luminosity and star formation rate, the radio-SFR relation, is potentially limited by various effects such as cosmic-ray transport, free-free absorption, and cosmic-ray electron energy losses. We aim to calibrate the radio-SFR relation in a sample of nearby galaxies ranging from dwarf to spiral galaxies covering nearly five orders of magnitude in SFR range. We include, both, global (individual galaxies) and local (spatially resolved, kiloparsec sized) measurements. We measured radio continuum luminosities at 144 MHz using observations with the LOw Frequency ARray (LOFAR) and measure radio spectral indices using ancillary 1.4GHz data. Selecting 70 nearby (distance d<30Mpc) galaxies, 15 of which were used for local measurements, with rich ancillary data we present a study of the radio-SFR relation using total infrared, mid-infrared, H{alpha}, and far-ultraviolet as complementary SFR tracers. About one third of our sample are at least moderately star-forming edge-on galaxies with the remaining ones chosen to be a representative sample of a wide range of morphological types and SFR values. For the first time, we show that the radio luminosity (L144), the star-formation rate (SFR), and the radio spectral index ({alpha}) define a "fundamental plane" in the [log(L144), log(SFR), {alpha}] space. This allows us to define a unified radio-SFR relation that works both for global and local data when using the radio spectral index as a second parameter. A unified radio-SFR relation for, both, global and local data may serve as a litmus test for galaxy simulations that include the effect of cosmic rays and magnetic fields. It also strengthens the case for using the radio-SFR relation as an extinction-free tracer of star formation.
Author(s): Heesen V.; Edler H.W.; Brueggen M.; Stein M.; Bomans D.J.; Paladino R.,Chyzy K.T.; Malek K.; Lara-Lopez M.A.; Tabatabaei F.S.
IVOA id: ivo://cds.vizier/j/a+a/712/a242

LAMOST MRS-N: 3854 nebula spectra from LAMOST DR7

2026-08-25T13:31:08Z

Description: We report multifiber, medium-resolution spectroscopy of the Rosette Nebula with full spatial coverages, and present a table of the nebular parameters based on the spatially resolved measurements of emission lines. These new observations were conducted through the Medium-Resolution Spectroscopic Survey of Nebulae (MRS-N) on the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). Comprehensive analyses were performed on a total of 3854 high-quality nebular spectra; so far, the most extensive spectral data set available for this nebula that encompasses an area of 4.52deg^2^. Various physical parameters, including relative line intensities, radial velocities (RVs), and full width at half-maximums (FWHMs), were derived through measurements of the H{alpha}, [N II] {lambda}{lambda}6548,6584 and [S II] {lambda}{lambda}6716,6731 emission lines detected in the LAMOST MRS-N spectra. For the first time, we found a bow-shaped feature in the spatial distribution of RVs of the Rosette Nebula. Moreover, the spatial distributions of RVs and FWHMs, as well as additional parameters such as gas temperature and turbulent velocity in the vicinity of the nebula, indicate possible interaction between Rosette and the nearby supernova remnant, Monoceros Loop. Our new observations provide indispensable measurements of the Rosette Nebula. The parameter table in particular can be used as valuable constraint on the chemo-dynamical modeling of the nebula, which will enable deeper understanding of the characteristics of this H II region.
Author(s): Zhang L.-Y.; Wu C.-J.; Fang X.; Zhang W.; Ren J.-J.; Chen J.-J.; Wu H.
IVOA id: ivo://cds.vizier/j/aj/170/309

DELVE DR2: Jacobi radii for 159 globular clusters

2026-08-25T11:27:23Z

Description: Extratidal features around globular clusters (GCs) are tracers of their disruption, stellar stream formation, and their host's gravitational potential. However, these features remain challenging to detect due to their low surface brightness. We conduct a systematic search for such features around 19 GCs in the DECam Local Volume Exploration (DELVE) survey Data Release 2, discovering a new extra-tidal envelope around NGC 5897 and find tentative evidence for an extended envelope surrounding NGC 7492. Through a combination of dynamical modeling and analyzing synthetic stellar populations, we demonstrate these envelopes may have formed through tidal disruption. We use these models to explore the detectability of these features in the upcoming Legacy Survey of Space and Time (LSST), finding that while LSST's deeper photometry will enhance detection significance, additional methods for foreground removal like proper motions or metallicities may be important for robust stream detection. Our results both add to the sample of globular clusters with extratidal features and provide insights on interpreting similar features in current and upcoming data.
Author(s): Chiti A.; Tavangar K.; Ferguson P.S.; Carballo-Bello J.A.; Senkevich A.M.,Erkal D.; Drlica-Wagner A.; Pace A.B.; Ji A.P.; Sand D.J.; Limberg G.,Chaturvedi A.; Crnojevic D.; Medina G.E.; Riley A.H.; Shipp N.,Vivas A.K.; Wertheim M.; Choi Y.; Martinez-Vazquez C.E.; Mutlu-Pakdil B.,Navabi M.; Sakowska J.D.; Stringfellow G.S.; Zenteno A.,DELVE Collaboration
IVOA id: ivo://cds.vizier/j/aj/170/294

The J-HERTz catalog from J-PLUS & LoTSS

2026-08-25T11:19:32Z

Description: We introduce J-HERTz (J-PLUS Heritage Exploration of Radio Targets at z<5), a new multiwavelength catalog that combines optical narrowband photometry from J-PLUS, infrared observations from the Wide-field Infrared Survey Explorer, and deep low-frequency radio data from LoTSS for nearly 0.5 million sources across 2100 deg2 of the northern sky. Key innovations of J-HERTz include Bayesian neural network classifications for 390,000 galaxies, 31,000 quasars, and 20,000 stars, along with significantly improved photometric redshifts for 235,000 galaxies compared to previous J-PLUS DR3 and LoTSS DR2 estimates. We identify 831 candidate Galactic radio stars, which, if confirmed, would constitute a significant addition to the number of radio-emitting stars identified to date. Among radio-loud galaxies with spectroscopic observations, >~20% lack Seyfert or LINER signatures, indicating a substantial population of optically quiescent radio galaxies, in agreement with previous works. Spectral energy distribution fitting of their host galaxies using J-PLUS photospectra reveals systematically low specific star formation rates, consistent with quenched stellar populations. J-HERTz thus provides a powerful data set to exploit radio-optical synergies, enabling studies that span from the origin of stellar radio emission to the active galactic nucleus life cycle and the role of jet activity in shaping host galaxy evolution.
Author(s): Fernandez Gil D.; Fernandez-Ontiveros J.A.; Lopez-Sanjuan C.,Arizo-Borillo F.; del Pino A.; Hernan-Caballero A.; Lumbreras-Calle A.,Rahna P.T.; Sobral D.; Ramio H.V.; Cenarro A.J.; Marin-Franch A.,Angulo R.E.; Ederoclite A.; Cristobal-Hornillos D.; Dupke R.A.,Hernandez-Monteagudo C.; Moles M.; Sodre L.J.; Varela J.
IVOA id: ivo://cds.vizier/j/apjs/282/20

Cataclysmic variables from DESI DR1 sp.

2026-08-25T11:06:22Z

Description: We present a systematic search for cataclysmic variables (CVs) using spectroscopic data from Data Release 1 of the Dark Energy Spectroscopic Instrument. Applying the Bagging-TopPush algorithm, we identified 433 CV candidates and related objects, of which 412 are confirmed CVs including 76 new systems. Subtypes were assigned through a combination of DESI spectra, Gaia data, and light curves from time-domain surveys, revealing populations of dwarf novae, novalike variables, magnetic CVs, and AM CVn binaries. Orbital periods were constrained from eclipsing light curves and DESI radial velocity curves for 14 systems. For 31 WZ Sge-type dwarf novae, we estimated white dwarf masses and radii by combining Galaxy Evolution Explorer ultraviolet photometry with DESI optical spectra, obtaining average values of 0.82M_{sun}_ for mass and 13452K for effective temperature. We also calculated the strength of the magnetic field for three polars based on the cyclotron features. Furthermore, we derived subtype-dependent space densities and found values consistent, within uncertainties, with those inferred from Sloan Digital Sky Survey, Gaia, and other survey data, though remaining lower than theoretical predictions by 1-2 orders of magnitude. Besides, we highlight several notable objects, including newly identified AM CVn systems, eclipsing systems in the period gap, donor-dominated binaries, and other unusual systems of particular interest for follow-up observations.
Author(s): Hou W.; Lin J.-M.; Luo A.-L.; Dai Z.-B.; Dong Y.-Q.; Ma S.-G.
IVOA id: ivo://cds.vizier/j/apjs/282/26

Green Bank Ammonia Survey (GAS) DR2

2026-08-25T09:38:42Z

Description: We present an overview of the final data release (DR2) from the Green Bank Ammonia Survey (GAS). GAS is a large program at the Green Bank Telescope to map all Gould Belt star-forming regions with A_V_>~7mag visible from the Northern Hemisphere in emission from NH3 and other key molecular tracers. This final release includes the data for all the regions observed: Heiles Cloud 2 and B18 in Taurus; Barnard 1, Barnard 1-E, IC 348, NGC 1333, L1448, L1451, and Per7/34 in Perseus; L1688 and L1689 in Ophiuchus; Orion A (North and South) and Orion B in Orion; Cepheus; B59 in Pipe; Corona Australis East and West; IC 5146; and Serpens Aquila and MWC297 in Serpens. Similar to what was presented in GAS DR1, we find that the NH3 emission and dust continuum emission from Herschel correspond closely. We find that the NH3 emission is generally extended beyond the typical 0.1pc length scales of dense cores, and we find that the transition between coherent core and turbulent cloud is a common result. This shows that the regions of coherence are common throughout different star-forming regions, with a substantial fraction of the high column density regions displaying subsonic nonthermal velocity dispersions. We produce maps of the gas kinematics, temperature, and NH3 column densities through forward modeling of the hyperfine structure of the NH3 (1,1) and (2,2) lines. We show that the NH3 velocity dispersion, {sigma}v, and gas kinetic temperature, TK, vary systematically between the regions included in this release, with an increase in both the mean value and spread of {sigma}v and TK with increasing star formation activity.
Author(s): Pineda J.E.; Friesen R.K.; Rosolowsky E.; Chacon-Tanarro A.; Chen M.C.-Y.,Di Francesco J.; Kirk H.; Punanova A.; Seo Y.; Shirley Y.; Ginsburg A.,Offner S.S.R.; Pandhi A.; Singh A.; Quan F.; Arce H.G.; Caselli P.,Choudhury S.; Goodman A.A.; Heitsch F.; Martin P.G.; Matzner C.D.,Myers P.C.; Redaelli E.; Scibelli S.; co-PIs; The GAS collaboration
IVOA id: ivo://cds.vizier/j/apjs/282/18

4-8GHz TMRT obs. of WISE point sources

2026-08-25T08:59:13Z

Description: We conducted a 6cm formaldehyde (H2CO) line survey across the northern sky, targeting 3149 high-mass star-forming region candidates selected from the all-sky Wide-field Infrared Survey Explorer (WISE) point-source catalog using the Shanghai TianMa 65m Radio Telescope. This survey detected H2CO absorption lines at 1156 positions and four known maser sources, achieving a detection rate of 36.7%. Among these, 14 candidates exhibited hyperfine structure splitting, all located at high Galactic latitudes (b>3{deg}). The Galactic spatial distribution of H2CO absorption line detections yields a scale height of ~71.8pc. Compared to the WISE infrared colors and magnitudes of 6.7GHz CH3OH masers and hydrogen radio-recombination lines (HRRLs), the distribution of H2CO absorption lines closely resembles that of HRRLs, albeit with higher [W4] magnitudes. The detection of these three lines in the same observational sample enables the classification of H2CO absorption lines into four groups representing distinct evolutionary stages. Variations in H2CO detection proportion, line width, and intensity across these groups probably reflect the influence of star formation feedback on the circumstellar medium during protostellar evolution. Observational updates over six years (2015-2021) of the 6cm H2CO maser in NGC 7538 IRS1 demonstrate that the flux density diverged from the prediction of the rotating ellipsoidal model, highlighting the need for further data to elucidate the maser variability mechanism.
Author(s): Liu J.-T.; Chen Xi; Ouyang X.-J.; Zhang Y.-K.; Song S.-M.; Zhao Z.; Li B.,Xia Bo; Shen Z.-Q.
IVOA id: ivo://cds.vizier/j/apjs/282/15

HWO: UV & X-ray catalog from archival data

2026-08-25T08:54:15Z

Description: We assess archival high-energy data for key stars on the Habitable Worlds Observatory (HWO) Target Stars and Systems 2025 list, as stellar radiation is critical to shaping and interpreting planetary atmospheres. Using a sample of 98 nearby stars (HWO Tier 1 targets), we compile and evaluate X-ray and ultraviolet (UV) data from archival eROSITA, Chandra, XMM-Newton, ROentgen SATellite, Extreme-Ultraviolet Explorer, Swift, Far Ultraviolet Spectroscopic Explorer, International Ultraviolet Explorer (IUE), Galaxy Evolution Explorer, and Hubble Space Telescope (HST). We examine spectral and temporal coverage, assess data quality, and identify major gaps. UV data are moderately available, with most coverage coming from near-UV spectra from IUE. Far fewer stars have far-UV spectra, especially from HST. In the X-ray regime, some stars have high-quality spectra, while others are limited to shallow detections or broadband photometry. A small fraction of the sample has both X-ray and UV spectra of sufficient quality to support full spectral energy distribution modeling. Truly comprehensive coverage across X-ray, extreme-UV, and both UV bands remains extremely rare. Most data sets are single-epoch, limiting assessments of variability and flares-key factors in atmospheric photochemistry and escape. Moreover, the lack of simultaneous or contemporaneous observations across bands adds further uncertainty. Our findings underscore the need for new space-based missions and coordinated multiwavelength campaigns, ideally with overlapping coverage, to improve stellar characterization for HWO. As several key observatories age and face potential decommissioning, there is a narrow window of opportunity to secure these critical data. Investing in this effort now will directly support the science goals of HWO and enhance future studies of planetary habitability.
Author(s): Peacock S.; Wilson D.J.; Richey-Yowell T.; Tuchow N.W.; France K.,Caballero J.A.; Spinelli R.; Corrales L.; Zelakiewicz A.S.; Redfield S.,Rockcliffe K.; Youngblood A.; Froning C.S.; Duvvuri G.M.; Binder B.A.,Hinkel N.R.; Mamajek E.E.
IVOA id: ivo://cds.vizier/j/aj/170/293

ALMA CO-CAVITY void galaxies physical properties

2026-08-25T08:51:44Z

Description: The environment plays a key role in galaxy evolution, yet it remains unclear how detailed molecular gas properties and their connection to star formation and stellar content are influenced by both large-scale and local environments. Here we introduce the ALMA CO-CAVITY project, the first interferome tric CO(1-0) survey of a large sample of 41 void galaxies (VGs) to characterise in detail their molecular gas properties. It is built over the CAVITY proje ct, offering optical integral field unit (IFU) data, enabling a direct, pixel-to-pixel comparison between molecular gas (from ALMA), star formation, and stellar properties, as well as the derivation of their scaling relations. In this work we present ALMA data products for our sample, containing data cubes, moment maps and position-velocity diagrams at angular resolutions of 1 arcsec. We also present molecular gas, stellar mass, and star formation rate surface density maps at a common resolution of 2.5 arcsec. We contextualise our sample against representative unresolved and resolved surveys. While our sample provides a good representation of the VG population and follows the distribution of key properties seen in star-forming galaxy samples, galaxies included in resolved studies from the literature tend to be more massive, less isolated, and located in denser large-scale environments. We present global scaling relat ions for the ALMA CO-CAVITY sample and find that the molecular gas main sequence exhibits the smallest scatter (0.21 dex), followed by the Schmidt-Kennicutt relation and the star-forming main sequence. From integrated properties alone, we find that these scaling relations for VGs are compatible with those for denser environments. This paper lays the foundation for forthcoming studies exploiting this unique dataset.
Author(s): Espada D.; De Daniloff S. B.; Duarte Puertas S.; Argudo-Fernandez M.,Lisenfeld U.; Verley S.; Perez I.; Rodriguez M. I.; Ruiz-Lara T.,Garcia-Benito R.; Sanchez-Menguiano L.; Sanchez-Portal M.; Bongiovanni A.,Sanchez S. F.; Jimenez A.; Miura R. E.; Torres-Rios G.,Villalba-Gonzalez P.; Gonzalez-Koda Y. K.; Bidaran B.; Alcazar-Laynez M.,Zurita A.; Florido E.; Vasquez-Bustos P.
IVOA id: ivo://cds.vizier/j/a+a/712/a227

Cosmographic constraints from FRBs

2026-08-25T08:33:50Z

Description: Late-time astrophysical probes offer a powerful way to investigate the expansion history of the Universe. Among these probes, fast radio bursts (FRBs) are millisecond-duration astrophysical transients whose extragalactic origin makes them a promising addition to studies of large-scale structure. Their dispersion measures encode information about the intervening cosmic plasma, which can be linked to cosmological distances. We used late-time probes, such as well-localized FRBs, baryon acoustic oscillations (BAO), supernovae (SNe), and cosmic chronometers (CC) to constrain cosmological parameters through a model-independent cosmographic approach. We integrated FRB data with BAOs from Dark Energy Spectroscopic Instrument (DESI) DR2, SNe, and CCs to derive constraints on the Hubble constant (H0), the deceleration parameter (q0), and the jerk parameter (j0), using Markov Chain Monte Carlo (MCMC) analysis for parameter estimation. The cosmographic approach with FRBs alone provides H0=66.35^+4.13^_-5.04_km/s/Mpc, q0=-0.33_-0.15_^+0.21^, and j0=0.83_-0.67_^0.57^, corresponding to a precision of ~6% for the Hubble constant and showing consistency with the {LAMBDA}CDM expectation. The DESI+CMB dataset yields H0=65.59^+1.25^_-1.24_km/s/Mpc, q0=-0.29_-0.08_^+0.07^, and j0=0.58_-0.04_^+0.03^, providing a ~2% precision on H0 and may suggest a possible tension in the late-time kinematic sector relative to the {LAMBDA}CDM expectation when BAO measurements are calibrated with a Planck-inferred sound horizon. Combining the FRB, SNe, DESI+CMB, and CC datasets further tightens the constraints to H0=68.03^+0.53^_-0.52_km/s/Mpc, q0=-0.41+/-0.02, and j0=0.55+/-0.02, with the jerk parameter remaining lower than j0=1 at the 1{sigma} confidence level. These findings hint at a possible late-time kinematic tension, as indicated by the inferred value of the jerk parameter, which is primarily driven by the DESI+CMB dataset under standard early-Universe assumptions for the sound horizon. At the current level of observational precision, FRBs play a complementary role in the cosmographic analysis, with their impact expected to increase as larger and more precise samples of well-localized events become available.
Author(s): Sales L.L.; de Farias K.E.L.; Queiroz A.R.; Santos J.R.L.; Batista R.A.,Oliveira A.R.M.; Santana L.F.; Wuensche C.A.; Villela T.; Vieira J.
IVOA id: ivo://cds.vizier/j/a+a/712/a236

Refined reduction of UBV photometry at Hvar

2026-08-25T08:28:41Z

Description: Emission-line stars classified as Be exhibit light and colour variability on various timescales, ranging from days to decades. Their evolution must be constrained by long-term observations that are accurately calibrated and stable. Here, we provide a new reduction of photoelectric UBV observations obtained at the Hvar observatory, spanning more than 50 years (1972-2025). This unique dataset is highly complementary to the Transiting Exoplanet Survey Satellite, which has been conducting observations since 2018, not only in terms of the time baseline, but also in providing fundamental constraints in the U and B bands. We used new, non-linear reduction equations, with temporally variable extinction over the course of the night, which allowed us to achieve long-term accuracy of 0.008-0.016mag (1-{sigma} uncertainty), as verified by the Johnson standards. We then classified 59 Be stars into five classes, based on their variability patterns; namely, long-term envelope (LTE), long-term cyclic (LTC), binarity (BIN), rapid low-amplitude (RLA), and long-term quiescence (LTQ). According to our observations, the percentages of stars in the individual classes are 44%, 24%, 25%, 66%, and 19%, respectively. We note that stars in the sample often exhibited more than one pattern. At certain times, changes in the U and B bands were markedly different from those in V (e.g. for BU Tau, V744 Her, V923 Aql, and V1294 Aql). We confirm that the LTE-positive variability is more common than the inverse (20 vs 6); in addition, two stars exhibited both types ({zeta} Tau and V1294 Aql). According to our observations, the LTC variability and the LTE-positive variability are almost mutually exclusive. Among 26 binary systems with previously known orbital solutions, circular orbits are more common than eccentric ones (18 vs 8). As for the brightness variations between different quiescent phases, an increasing trend is less common than a decreasing one (4 vs 7); spanning from -6.5 to +6.0mmag/yr. Our observations provide well-calibrated UBV light curves spanning several decades, offering a valuable dataset for investigations of Be-star variability and tests of various models, including the viscous decretion disc model. Continuous monitoring is important for the most interesting objects, namely, {beta} Lyr, EW Lac, {delta} Sco, {gamma} Cas, and V1294 Aql.
Author(s): Bozic H.; Harmanec P.; Broz M.; Oplistilova A.; Koubsky P.; Hadrava P.,Ruzdjak D.; Sudar D.; Wolf M.; Zasche P.; Honsa J.; Zdarsky F.; Harmanec A.,Jonak J.; Piantschitsch I.; Skokic I.; Svrckova J.; Vitovsky K.; Vrsnak D.,Zummer M.
IVOA id: ivo://cds.vizier/j/a+a/712/a226

Green Peas from SDSS DR18

2026-08-25T08:17:47Z

Description: The currently known compact extreme emission-line galaxies (the "Green Peas" (GPs)) in the Sloan Digital Sky Survey (SDSS) are rare and were mostly found among serendipitous spectroscopic targets, thus leaving open the possibility that a substantial population of GPs is missed. A significantly larger number of identified GPs in the Local Universe might provide a better characterization of their high-redshift analogs and Lyman continuum escape. In this paper, we confront the challenges of robustly identifying GPs without spectroscopic information, a needed approach considering the incompleteness of spectroscopic surveys for compact sources. The principal difficulty stems from a significant contamination of photometric candidates by stars and quasars of similar color. To solve this, we introduce a spectral energy distribution matching method, which separates candidate GPs from contaminants on the basis of SDSS and Wide-field Infrared Survey Explorer photometry of spectroscopically confirmed stars, quasars, and galaxies. The method has an effectiveness of 85% and a contamination rate of ~10%. With it, we identify ~9600 GP candidates expected to lie in the 0.12<z<0.36 range-a tenfold increase over what would be selected using SDSS DR18 spectra. Some of the new GPs are as bright as r~19, and 1200 are predicted to have [OIII]5007 equivalent widths in excess of 500{AA}. The new population contains many "Extended Peas," which are absent among known GPs and possibly represent merging systems. We provide catalogs containing 8313 newly identified GP candidates, as well as 917 GPs confirmed using SDSS spectroscopy and 521 GPs with spectroscopic redshifts from LAMOST and other sources.
Author(s): Samonski H.; Salim S.; Salzer J.J.
IVOA id: ivo://cds.vizier/j/apjs/282/14

Iron Spread in globular clusters

2026-08-25T08:15:52Z

Description: Globular clusters host multiple stellar populations, likely composed of a subset of first-generation stars that enriched the intracluster medium and gave rise to second-generation (SG) stars, each characterised by distinctive chemical patterns. These patterns typically include enhancements in elements such as N, Na, and Al, coupled with depletions in C, O, and Mg in SG stars. Traditionally, heavier elements such as those in the iron peak were considered unaffected in most clusters. However, recent studies have reported significant internal spreads in these elements, suggesting a more complex picture of chemical enrichment within globular clusters. This study seeks to derive precise and homogeneous differential iron abundances in a large sample of globular clusters. By doing so, our aim is to investigate the presence of intrinsic iron spreads within them and to assess the existence of differences in Fe between their stellar populations. We used the Python-based tool Q2 to determine both differential stellar parameters and iron abundances for 92 sibling stars -- defined by the similarities in their stellar parameters -- across 13 Galactic globular clusters. This differential approach reduces the influence of non-local thermodynamic equilibrium effects, and minimises observational errors, and systematic biases linked to stellar parameters. We performed Monte Carlo simulations to evaluate the statistical significance of the measured spreads. Most of the globular clusters in our sample do not show evidence of statistically significant iron spreads. Only a few exceptions emerge, namely NGC1851, NGC3201, and NGC5634, which display a highly significant iron spread. In particular, NGC3201 shows a particularly pronounced spread in its first-generation population, reflecting a potential inhomogeneous iron abundance in its pristine material. Finally, through statistical tests, we conclude that our data do not support the presence of a widespread iron variation in globular clusters.
Author(s): Schiappacasse-Ulloa J.; Lucatello S.; Magrini L.; Bragaglia A.; Carretta E.
IVOA id: ivo://cds.vizier/j/a+a/712/a219

X-Shooter acc disc properties of Sco-Cen stars

2026-08-25T08:12:26Z

Description: The evolution of protoplanetary discs is intertwined with the process of planet formation, growth and migration. Studies of nearby star-forming regions of different ages and properties provide the information needed to understand the processes governing their evolution. This paper presents the results of a spectroscopic study of the stellar and accretion properties of a large sample of 127 stars with protoplanetary discs in the Upper Scorpius region, a relatively old (5-10Myr), nearby (~145pc) star-forming region, with disc dust masses inferred from ALMA continuum measurements. We derived the accretion luminosity from the excess UV continuum emission with respect to the photospheric and chromospheric emission self-consistently with the stellar spectral types, extinction, and luminosity, using the FitteR for Accretion ProPErties of T Tauri stars (FRAPPE) code. We applied a new method to evaluate upper limits on the accretion luminosity. In ~50% of cases, we could only evaluate upper limits on the accretion luminosity, either because the signal-to-noise ratio of the data was insufficient or because the measured value of the accretion luminosity was below the statistical estimate of the emission due to chromospheric activity. The mass accretion rate shows a weak correlation with stellar mass, while we find no correlation with disc properties such as dust mass or gaseous disc radius. The dispersion is larger than that found in younger star-forming regions such as Lupus and Chamaeleon I, and suggests fading of the correlations with age. We find no evidence that the observed dispersion can be explained by membership in Upper Scorpius sub-groups, or by the properties of known binary systems or transition discs. The lack of correlation and the large dispersion of accretion rates challenge the current expectations of evolutionary models. The observed properties point to a decoupling of the inner and outer discs by the age of Upper Scorpius and a fading of the relations observed in younger star-forming regions, which calls for further development of current theoretical frameworks to be explained.
Author(s): Empey A.; Manara C.F.; Garcia Lopez R.; Natta A.; Claes R.; Zagaria F.,Alcala J.M.; Anania R.; Beccari G.; Carpenter J.; Facchini S.; Fedele D.,Lodato G.; Mauco K.; Miotello A.; Nisini B.; Pascucci I.; Piscarreta L.,Rosotti G.; Scholz A.; Testi L.; Vioque M.
IVOA id: ivo://cds.vizier/j/a+a/712/a222

GALAH survey DR4

2026-08-24T09:06:26Z

Description: The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical fingerprints of stars from high-resolution spectroscopy. The fourth data release (DR4) of the Galactic Archaeology with HERMES (GALAH) Survey, based on a decade of observations, provides the chemical abundances of up to 32 elements for 917 588 stars that also have exquisite astrometric data from the Gaia satellite. For the first time, these elements include life-essential nitrogen to complement carbon, and oxygen as well as more measurements of rare-earth elements critical to modern-life electronics, offering unparalleled insights into the chemical composition of the Milky Way. For this release, we use neural networks to simultaneously fit stellar parameters and abundances across the whole wavelength range, leveraging synthetic grids computed with Spectroscopy Made Easy. These grids account for atomic line formation in non-local thermodynamic equilibrium for 14 elements. In a two-iteration process, we first fit stellar labels to all 1 085 520 spectra, then co-add repeated observations and refine these labels using astrometric data from Gaia and 2MASS photometry, improving the accuracy and precision of stellar parameters and abundances. Our validation thoroughly assesses the reliability of spectroscopic measurements and highlights key caveats. GALAH DR4 represents yet another milestone in Galactic archaeology, combining detailed chemical compositions from multiple nucleosynthetic channels with kinematic information and age estimates. The resulting dataset, covering nearly a million stars, opens new avenues for understanding not only the chemical and dynamical history of the Milky Way but also the broader questions of the origin of elements and the evolution of planets, stars, and galaxies.
Author(s): Buder S.; Kos J.; Wang X.E.; McKenzie M.; Howell M.; Martell S.,Hayden M.R.; Zucker D.B.; Nordlander T.; Montet B.; Traven G.,Bland-Hawthorn J.; De Silva G.M.; Freeman K.; Lewis G.; Lind K.; Sharma S.,Simpson J.D.; Stello D.; Zwitter T.; Amarsi A.M.; Armstrong J.J.; Banks K.,Beavis M.; Beeson K.-L.; Chen B.; Ciuca I.; Da Costa G.S.; de Grijs R.,Martin B.; Nataf D.M.; Ness M.; Rains A.D.; Scarr T.; Vogrincic R.,Purmortal Wang Z.; Wittenmyer R.A.; Xie Y.A.; GALAH Coll.
IVOA id: ivo://cds.vizier/j/other/pasa/42.51

Ultracool and brown dwarf candidates

2026-08-24T08:25:47Z

Description: Ultracool and brown dwarf candidates (d_{sun}_<=125pc, |b|>8deg) were identified via multiband and astrometric data from CatWISE (W1, W2), 2MASS (J, H, Ks), and Gaia DR3 (G, G_RP_, parallax, proper motions). N~11.8x10^3^ candidates emerged once simultaneously constrained by color and absolute magnitude criteria (e.g., G-W2>=1.75(G-J)-2.25), whereby ~350 sources are absent from the Gaia Ultracool Dwarf (UCD) catalog. Spectral types were approximated using a hybrid M_G_-M_W1_ sigmoid that offers additional temperature coverage in certain cases. Subsequent efforts may focus on extending sampling to the deeper NIR VVVX footprint that partly encompasses the Galactic plane, and over the long-term spectroscopically (in)validating candidates missing from the Gaia UCD database.
Author(s): Majaess D.; Minniti D.; Gomez M.; Saito R.K.; Navarros M.G.
IVOA id: ivo://cds.vizier/j/other/apss/371.85

RVs and activity indices of 8 stars

2026-08-24T07:47:22Z

Description: The astrometric measurements provided by the Gaia space mission represent a key advancement in the search and characterization of exoplanets, helping in particular to solve the mass degeneracy intrinsic to the radial velocity (RV) method. The fact that a fraction of astrophysical false positives contaminates the current catalog of astrometric candidate solutions requires an RV follow-up to validate and confirm such candidates. Within the GAPS programme, we have observed a selected sample of 14 stars having Gaia astrometric solutions compatible with the presence of a substellar companion. The immediate aim of this survey is to identify astrophysical false positives and provide the first RV validation and confirmation of the remaining candidates. We analysed data collected with the HARPS-N spectrograph to identify stellar binary systems from the spectral cross-correlation function profiles. The remaining astrometric candidates were characterized via Markov chain Monte Carlo analysis searching for the best-fit RV solution. Among the stars in our sample with astrometric candidate solutions, we identify 6 as originating from close binary companions mimicking the astrometric motion of distant substellar companions, from which we can estimate an updated value of 43_-11_^+13^% for the binary contamination fraction in the Gaia DR3 catalog of astrometric candidates. We validate and confirm the remaining 8 solutions, corresponding to giant and brown dwarf companions with minimum masses between 8 and 62M_Jup_ and semimajor axes between 0.76 and 1.42 au, providing the first RV characterization for 6 of these candidates and updated orbital solutions for 2 previously confirmed ones
Author(s): Barbato D.; Pinamonti M.; Sozzetti A.; Desidera S.; D'Orazi V.,Maldonado J.; Biazzo K.; Naponiello L.; Lanza A.F.; Bignamini A.,Bonomo A.S.; Brogi M.; Cabona L.; Damasso M.; Gratton R.; Mancini L.,Mantovan G.; Nardiello D.; Rainer M.; Guilluy G.; Giacobbe P.; Malavolta L.,Cosentino R.; Boschin W.; Claudi R.
IVOA id: ivo://cds.vizier/j/a+a/712/a213

V432 Dra UBVRI(RI)c light curves

2026-08-21T12:58:49Z

Description: A little-studied eclipsing star with an elliptical orbit, V432 Dra (V=12.23mag, P=11.63 days, e=0.37, F8 V + F8 V) turned out to be a relatively young system with accelerated apsidal rotation. The following absolute parameters of the component stars were obtained for the first time: T1=6240+/-40K, M1=1.13+/-0.05M_{sun}_, R1=1.10+/-0.02R_{sun}_, T2 = 6215+/-40K, M2=1.12+/-0.05M_{sun}_, R2=1.09+/-0.02R_{sun}_. The relativistic contribution to the apsidal rotation is six times greater than the classical effect, but the observed apsidal period Paps = 13060+/-190 yrs is more than three times shorter than the theoretical value. The photometric parallax of pi=0.00197" (d=507pc) is based on the Gaia value. In evolutionary diagrams, the system is near the Zero Age Main Sequence at an age of 700 mln yrs and shows a metal deficiency of [Fe/H]=-0.17.
Author(s): Volkova A.S.; Volkov I.M.; Naroenkov S.A.
IVOA id: ivo://cds.vizier/j/other/arep/70.461

Euclid. Convective-transition gap of 47 Tuc

2026-08-21T07:46:41Z

Description: We report the first detection of the `convective-transition gap' (also known as the `M-dwarf gap') in the globular cluster 47 Tuc (NGC 104). This feature, linked to a change in the physical properties of late-type dwarfs, has remained elusive, with only two detections so far. Leveraging the large number of stars, high resolution, and photometric precision enabled by Euclid, we detected a statistically significant, sharp discontinuity in the main-sequence luminosity function of 47 Tuc at I_E_~22.9, which we identify as the convective-transition gap. A comparison of the observed properties of the gap in 47 Tuc with theoretical models shows how the gap can be a powerful diagnostic for probing the internal chemical structure of globular clusters and their multiple stellar populations. Following its initial discovery in the metal-poor cluster NGC 6397, the identification of a convective gap in the metal-rich 47 Tuc suggests that this feature is more general than previously thought. These results demonstrate that Euclid can be transformative well beyond cosmology, with impacts across multiple areas of astrophysics, including resolved stellar populations.
Author(s): Libralato M.; Griggio M.; Gerasimov R.; Bedin L.R.; McDonald I.; Altieri B.,Anderson J.; Annibali F.; Balbinot E.; Battaglia G.; Bellini A.,Casenove P.; Cuillandre J.-C.; Dalessandro E.; Ferguson A.M.N.,Jones H.R.A.; Kuijken K.; Majidi F.Z.; Massari D.; Mohandasan A.,Niederhofer F.; Polenta G.; Sakowska J.D.; Soldano F.; Zerbinati C.,Andreon S.; Auricchio N.; Aussel H.; Baccigalupi C.; Baldi M.; Balestra A.,Battaglia P.; Biviano A.; Branchini E.; Brescia M.; Camera S.,Capobianco V.; Carbone C.; Carretero J.; Castellano M.; Castignani G.,Cavuoti S.; Chambers K.C.; Cimatti A.; Colodro-Conde C.; Congedo G.,Conselice C.J.; Conversi L.; Copin Y.; Courbin F.; Courtois H.M.,Cropper M.; Degaudenzi H.; De Lucia G.; Dole H.; Dubath F.; Dupac X.,Farina M.; Farinelli R.; Faustini F.; Ferriol S.; Frailis M.; Franceschi E.,Galeotta S.; George K.; Gillis B.; Giocoli C.; Gracia-Carpio J.; Grazian A.,Grupp F.; Haugan S.V.H.; Hoekstra H.; Holmes W.; Hook I.M.; Hormuth F.,Hornstrup A.; Jahnke K.; Jhabvala M.; Kermiche S.; Kiessling A.; Kubik B.,Kummel M.; Kunz M.; Kurki-Suonio H.; Le Brun A.M.C.; Ligori S.; Lilje P.B.,Lindholm V.; Lloro I.; Mansutti O.; Marggraf O.; Martinelli M.; Martinet N.,Marulli F.; Massey R.J.; Medinaceli E.; Mei S.; Meneghetti M.; Merlin E.,Meylan G.; Mora A.; Moscardini L.; Nakajima R.; Nichol R.C.; Niemi S.-M.,Padilla C.; Paltani S.; Pasian F.; Percival W.J.; Pettorino V.; Poncet M.,Popa L.A.; Raison F.; Renzi A.; Rhodes J.; Riccio G.; Rizzo F.; Romelli E.,Roncarelli M.; Saglia R.; Sakr Z.; Sapone D.; Schirmer M.; Schneider P.,Schrabback T.; Secroun A.; Sihvola E.; Simon P.; Sirignano C.; Sirri G.,Stanco L.; Tallada-Cresp'i P.; Taylor A.N.; Tereno I.; Toft S.,Toledo-Moreo R.; Torradeflot F.; Tutusaus I.; Valiviita J.; Vassallo T.,Wang Y.; Weller J.; Scott D.
IVOA id: ivo://cds.vizier/j/a+a/712/a174

Euclid Q1 strong gravitational lens

2026-08-21T07:27:07Z

Description: We present an end-to-end, iterative pipeline for efficient identification of strong galaxy-galaxy lensing systems, applied to the Euclid Q1 imaging data. Starting from VIS catalogues, we reject point sources, apply a magnitude cut (IE<=24) on deflectors, and run a pixel-level artefact/noise filter to build 96x96 pix cutouts; VIS+NISP colour composites are constructed with a VIS-anchored luminance scheme that preserves VIS morphology and NISP colour contrast. A VIS-only seed classifier supplies clear positives and typical impostors, from which we curate a morphology-balanced negative set and augment scarce positives. Among the six compact CNNs studied initially, a modified VGG16 (GlobalAveragePooling + 256/128 dense layers with the last nine layers trainable) performs best; the training set grows from 27 seed lenses (augmented 67x to 1809) plus 2000 negatives to a colour dataset of 30686 images. After three rounds of iterative fine-tuning, human grading of the top 4000 candidates ranked by the final model yields 441 Grade A/B candidate lensing systems, including 311 overlapping with the existing Q1 strong-lens catalogue, and 130 additional A/B candidates (9 As and 121 Bs) not previously reported. Independently, the model recovers 740 out of 905 (81.8%) candidate Q1 lenses within its top 20000 predictions, considering off-centred samples. Candidates span IE~17-24 AB mag (median 21.3 AB mag) and are redder in YE-HE than the parent population, consistent with massive early-type deflectors. Each training iteration required about a week for a small team, and the approach easily scales to future wide-area Euclid releases; future work will calibrate the selection function via lens injection, extend recall through uncertainty-aware active learning, and explore multi-scale or attention-based neural networks with fast post-hoc vetters that incorporate lens models into the classification.
Author(s): Euclid Coll.; Xu X.; Chen R.; Li T.; Cooray A.R.; Schuldt S.,Acevedo Barroso J.A.; Stern D.; Scott D.; Meneghetti M.; Despali G.,Chopra J.; Cao Y.; Cheng M.; Buda J.; Zhang J.; Furumizo J.; Valencia R.,Jiang Z.; Tortora C.; Lines N.E.P.; Collett T.E.; Fotopoulou S.; Galan A.,Manjon-Garcia A.; Gavazzi R.; Iwamoto L.; Kruk S.; Millon M.; Nugent P.,Saulder C.; Sluse D.; Wilde J.; Walmsley M.; Courbin F.; Metcalf R.B.,Altieri B.; Amara A.; Andreon S.; Auricchio N.; Baccigalupi C.; Baldi M.,Balestra A.; Bardelli S.; Battaglia P.; Bender R.; Biviano A.; Branchini E.,Brescia M.; Camera S.; Capobianco V.; Carbone C.; Cardone V.F.,Carretero J.; Casas S.; Castellano M.; Castignani G.; Cavuoti S.,Cimatti A.; Colodro-Conde C.; Congedo G.; Conselice C.J.; Conversi L.,Copin Y.; Courtois H.M.; Cropper M.; Da Silva A.; Degaudenzi H.,De Lucia G.; Dolding C.; Dole H.; Dubath F.; Dupac X.; Dusini S.,Escoffier S.; Farina M.; Farinelli R.; Farrens S.; Ferriol S.; Finelli F.,Fosalba P.; Frailis M.; Franceschi E.; Fumana M.; Galeotta S.; George K.,Gillard W.; Gillis B.; Giocoli C.; Gomez-Alvarez P.; Gracia-Carpio J.,Grazian A.; Grupp F.; Haugan S.V.H.; Holmes W.; Hormuth F.; Hornstrup A.,Jahnke K.; Jhabvala M.; Joachimi B.; Kermiche S.; Kiessling A.; Kubik B.,Kuemmel M.; Kunz M.; Kurki-Suonio H.; Le Brun A.M.C.; Ligori S.,Lilje P.B.; Lindholm V.; Lloro I.; Mainetti G.; Maiorano E.; Mansutti O.,Marcin S.; Marggraf O.; Martinelli M.; Martinet N.; Marulli F.; Massey R.J.,Medinaceli E.; Mei S.; Melchior M.; Merlin E.; Meylan G.; Mora A.,Moresco M.; Moscardini L.; Nakajima R.; Neissner C.; Nichol R.C.,Niemi S.-M.; Nightingale J.W.; Padilla C.; Paltani S.; Pasian F.,Pedersen K.; Percival W.J.; Pettorino V.; Polenta G.; Poncet M.; Popa L.A.,Raison F.; Renzi A.; Rhodes J.; Riccio G.; Romelli E.; Roncarelli M.,Saglia R.; Sakr Z.; Sapone D.; Schirmer M.; Schneider P.; Schrabback T.,Secroun A.; Seidel G.; Sihvola E.; Simon P.; Sirignano C.; Sirri G.,Stanco L.; Tallada-Crespi P.; Taylor A.N.; Tereno I.; Tessore N.; Toft S.,Toledo-Moreo R.; Torradeflot F.; Tutusaus I.; Valenziano L.; Valiviita J.,Vassallo T.; Verdoes Kleijn G.; Veropalumbo A.; Wang Y.; Weller J.,Zacchei A.; Zamorani G.; Zerbi F.M.; Zucca E.; Ballardini M.; Bolzonella M.,Burigana C.; Cabanac R.; Calabrese M.; Cappi A.; Castro T.,Escartin Vigo J.A.; Gabarra L.; Hemmati S.; Macias-Perez J.; Maoli R.,Martin-Fleitas J.; Mauri N.; Monaco P.; Nucita A.A.; Pezzotta A.,Poentinen M.; Risso I.; Scottez V.; Sereno M.; Tenti M.; Tucci M.; Viel M.,Wiesmann M.; Akrami Y.; Andika I.T.; Angora G.; Anselmi S.; Archidiacono M.,Atrio-Barandela F.; Bazzanini L.; Bergamini P.; Bertacca D.; Bethermin M.,Beutler F.; Blot L.; Borgani S.; Brown M.L.; Bruton S.; Calabro A.,Camacho Quevedo B.; Caro F.; Carvalho C.S.; Cogato F.; Conseil S.,Cucciati O.; Davini S.; Desprez G.; Diaz-Sanchez A.; Di Domizio S.,Diego J.M.; Duc P.-A.; Duret V.; Elkhashab M.Y.; Enia A.; Fang Y.,Finoguenov A.; Franco A.; Ganga K.; Gasparetto T.; Gaztanaga E.,Giacomini F.; Gianotti F.; Gozaliasl G.; Guidi M.; Gutierrez C.M.; Hall A.,Hernandez-Monteagudo C.; Hildebrandt H.; Hjorth J.; Kajava J.J.E.; Kang Y.,Kansal V.; Karagiannis D.; Kiiveri K.; Kim J.; Kirkpatrick C.C.; Lepori F.,Leroy G.; Lesci G.F.; Lesgourgues J.; Liaudat T.I.; Liu S.J.,Magliocchetti M.; Magnier E.A.; Mannucci F.; Martins C.J.A.P.; Maurin L.,Miluzio M.; Moretti C.; Morgante G.; Naidoo K.; Navarro-Alsina A.,Nesseris S.; Paoletti D.; Passalacqua F.; Paterson K.; Patrizii L.,Pisani A.; Potter D.; Pratt G.W.; Quai S.; Radovich M.; Rojas K.; Roster W.,Sacquegna S.; Sahlen M.; Sanders D.B.; Sarpa E.; Scarlata C.; Schneider A.,Schultheis M.; Sciotti D.; Sellentin E.; Smith L.C.; Tanidis K.; Tao C.,Tarsitano F.; Testera G.; Teyssier R.; Tosi S.; Troja A.; Venhola A.,Vergani D.; Vernardos G.; Verza G.; Vinciguerra S.; Walton N.A.,Wright A.H.; Yeung H.W.
IVOA id: ivo://cds.vizier/j/a+a/712/a207

AMS-02 All Particle Rates Catalog

2026-08-21T00:00:00Z

Description: The AMS02RATES database table records the incident rates for all particle species obtained with the Alpha Magnetic Spectrometer (AMS-02) experiment on the International Space Station (ISS), a cosmic ray particle detector installed in May 2011. The experiment consists of several components, which collectively measure particle species, energy, geomagnetic rigidity, or veto off-axis particles and high-energy photons. The experiment covers the energy range of ~0.1 GeV - ~2 TeV. AMS-02 is the result of a collaboration between MIT, the University of Hawaii, CERN, NASA, the U.S. Department of Energy, and ESA. It was launched on the Space Shuttle Endeavor (STS-134) on May 16, 2011 and was installed three days later at which time science operations commenced. Operations were interrupted by in-flight servicing of the cooling pumps for the silicon tracker: servicing took place between November 2019 and January 2020, after which science operations were restored. It is anticipated to continue operations for as long as the ISS itself remains functional. The rate at which all particle species are observed within a one-second time integration period is recorded for each interval, corrected for the livetime fraction. Each integration period contains the livetime value, observed rate, and the position of the AMS-02 instrument in latitude, longitude, and radius from the Earth's center in the Earth Centered Earth Fixed (ECEF) frame of reference. This database table was first ingested by the HEASARC in July 2026. The AMS-02 team in collaboration with the HEASARC developed the FITS file structure for these data which were created by the HEASARC from daily particle rate data provided by the AMS collaboration. The data and the database table are updated periodically to reflect additional data as they become available. This is a service provided by NASA HEASARC .
Author(s): HEASARC
IVOA id: ivo://nasa.heasarc/ams02rates

AMS-02 Spectral Results Catalog

2026-08-21T00:00:00Z

Description: The AMS02SPEC database table records the spectral results obtained with the Alpha Magnetic Spectrometer (AMS-02) experiment on the International Space Station (ISS), a cosmic ray particle detector installed in May 2011. The experiment consists of several components, which collectively measure particle species, energy, geomagnetic rigidity, or veto off-axis particles and high-energy photons. The experiment covers the energy range of ~0.1 GeV - ~2 TeV. AMS-02 is the result of a collaboration between MIT, the University of Hawaii, CERN, NASA, the U.S. Department of Energy, and ESA. It was launched on the Space Shuttle Endeavor (STS-134) on May 16, 2011 and was installed three days later at which time science operations commenced. Operations were interrupted by in-flight servicing of the cooling pumps for the silicon tracker: servicing took place between November 2019 and January 2020, after which science operations were restored. It is anticipated to continue operations for as long as the ISS itself remains functional. This database table was first ingested by the HEASARC in June 2026. The AMS-02 team in collaboration with the HEASARC developed the FITS file structure for these data. The data have been published in a series of papers (see bibliographic references) and archived in FITS format at the HEASARC. The data and the database table are updated periodically to reflect additional data as they becomes available. This is a service provided by NASA HEASARC .
Author(s): HEASARC
IVOA id: ivo://nasa.heasarc/ams02spec

Chandra Source Catalog Stacked Observation Detections, v2.1.1

2026-08-21T00:00:00Z

Description: The Chandra Source Catalog's Stacked Observation Detections Table (CSCSTACK) includes 493,236 detections (855,402 total entries consisting of detections plus photometric upper limits) based on 10,034 stacks of X-ray observations. Exploiting the unique resolution and very low background of Chandra data, the limiting sensitivity of the catalog is enhanced significantly by stacking (co-adding) multiple observations of the same field prior to source detection. To minimize the impact of the variation in the Chandra point spread function (PSF) with off-axis angles, source detection is constrained to run on stacks of observations that have telescope pointings that are co-located within 60 arcseconds and that were obtained using the same instrument (ACIS or HRC-I). Formally, the observations are matched using a tree clustering algorithm with complete linkage. This means that the pointing direction of every observation in the stack is co-aligned with the pointing direction of every other observation in the stack within 60 arcseconds. The stacked-observation level allows composite properties to be reported from the co-added observations for detections that would otherwise not be visible or have poor S/N in individual observations, while for higher S/N detections the per-observation properties facilitate analysis of variable sources. CSCSTACK is related to the <a href="/W3Browse/chandra/csc.html">Chandra Source Catalog (CSC)</a> catalog, which is the definitive catalog of X-ray sources detected by the Chandra X-ray Observatory. The CSC contains 407,806 unique compact and extended X-ray sources. By combining Chandra's sub-arcsecond on-axis spatial resolution and low instrumental background with consistent data processing, the CSC delivers a wide variety of uniformly calibrated properties and science ready data products for detected sources over four decades of flux. Each identified distinct X-ray source on the sky is represented in the catalog by one or more "stack detection" entries -- one for each stack in which the source has been detected -- and a single "master source" entry. The individual stack entries record all of the properties about a detection extracted from a single stack, as well as associated file-based data products, which are stack-specific. If a source is detected in one or more stacked-observations, photometric upper limits that are useful for temporal variability analyses are calculated for any overlapping stacked- and individual-observations in which the source is not detected. This database table was ingested by the HEASARC in July 2026 and is based on a download of the online version of the "Stacked Observation Detections" Table v. 2.1.1, at the CXC using the CLI. Refer to <a href="https://cxc.harvard.edu/csc/cli/">https://cxc.harvard.edu/csc/cli/</a> for details. This is a service provided by NASA HEASARC .
Author(s): Evans, Civano
IVOA id: ivo://nasa.heasarc/cscstack

Swift-XRT Living Point Source Catalog (LSXPS)

2026-08-21T00:00:00Z

Description: This is the Live Swift X-ray Point Source (LSXPS) catalog of detections by the Swift X-ray Telescope (XRT) used in Photon Counting (PC) mode in the 0.3-10 keV energy range. Swift is a NASA mission with international participation dedicated to studying gamma-ray bursts. It carries three instruments. The BAT is the large field-of-view instrument and operates in the 10-300 keV energy band; and two narrow field instruments, XRT and UVOT, that operate in the X-ray and UV/optical regime, respectively. This catalog is similar to the <a href="swift2sxps.html">2SXPS</a> catalog (Evans, P. A., et al. 2020, ApJS, 247, 54) and uses an almost identical source detection process. The primary change is that this is a living catalog: it is updated in near-real time and transient searches are carried out on each dataset as it is received. The improved statistics (below) compared to 2SXPS for source detections, unique and variables sources, uncatalogued sources, and temporal and total sky area coverage are a function of its ongoing live nature, compared to the static 2SXPS which was current up to 2018-08-01. On average, LSXPS grows by 49 new sources and the unique sky coverage increases 0.94 square degrees per day. This table was added to the HEASARC database in June 2026 and is based on the contents of its dedicated website at <a href="https://www.swift.ac.uk/LSXPS">https://www.swift.ac.uk/LSXPS</a>. The version available from the HEASARC corresponds to the catalog designated as "Sources" on the Leicester website and will typically be updated at the HEASARC within a day or so of a new version appearing on the Leicester website. This is a service provided by NASA HEASARC .
Author(s): Evans et al.
IVOA id: ivo://nasa.heasarc/swiftlsxps

AGN flares from ZTF DR23

2026-08-20T14:11:23Z

Description: Active galactic nuclei (AGNs) are known to exhibit stochastic variability across a wide range of timescales and wavelengths. AGN flares are extreme outbursts that deviate from this typical behavior and may trace a range of energetic physical processes. Using 6yr of data from Zwicky Transient Facility Data Release 23, we conduct a systematic search for AGN flares among a sample of well-sampled AGNs and AGN candidates. We construct two catalogs: the AGN Flare Coarse Catalog, containing 28,504 flares identified via Bayesian blocks and Gaussian processes, and the AGN Flare Refined Catalog, comprising 1984 high-confidence flares selected using stricter criteria. We analyze their spatial distribution, temporal characteristics, host-AGN type, and potential origins. Some flares can be associated with known supernovae, tidal disruption events, or blazars, and a few may be linked to binary black hole mergers or microlensing events.
Author(s): He L.; Liu Z.-Y.; Niu R.; Zhou M.-S.; Zou P.-R.; Gao B.-Z.; Liang R.-D.,Zhu L.-G.; Wang J.-M.; Jiang N.; Cai Z.-Y.; Jiang J.-A.; Dai Z.-G.,Yuan Y.-F.; Chen Y.-J.; Zhao W.
IVOA id: ivo://cds.vizier/j/apjs/282/13

HI dwarf galaxies in FASHI with DECaLS DR9 phot.

2026-08-20T12:58:04Z

Description: We present a sample of low HI mass (M_HI_<10^8^M_{sun}_) dwarf galaxies detected by The FAST All Sky HI Survey (FASHI) project. Due to the faint and irregular morphology of these galaxies, the default photometry is often inaccurate. Therefore, we utilized The Dark Energy Camera Legacy Survey data to perform careful photometric measurements, and find that the low HI mass galaxies have similar stellar mass densities to dwarf elliptical galaxies. Compared to other dwarf galaxy populations, the HI-selected dwarfs exhibit higher stellar mass densities than ultradiffuse galaxies, and similar densities to HI-selected low-surface-brightness galaxies, albeit with lower stellar masses, suggesting a possible evolutionary connection among these populations. By classifying the galaxies according to their HI spectral-line profiles, we show that the double-peaked sources conform closely to the Tully-Fisher relation, whereas the single-peaked sources follow the Faber-Jackson relation but with large scatter. This indicates that the single-peaked systems are likely dispersion dominated and that the relationship between stellar mass and halo mass in such systems may remain consistent across both low- and high- mass regimes. These findings suggest that HI-selected dwarf galaxies with single-peaked HI profiles may share a similar dynamical state with massive ellipticals, offering new insights into their structural evolution and the diversity of formation pathways for low-mass galaxies.
Author(s): Cheng C.; Huang J.-S.; Du W.; Zhang H.-X.; Zhang C.-P.; Zhu M.,Orellana G.
IVOA id: ivo://cds.vizier/j/apjs/281/66

Optical photometry & sp. of type IIn SN2021qqp

2026-08-20T12:09:50Z

Description: We present optical photometry and spectroscopy of the Type IIn supernova (SN) 2021qqp. Its unusual light curve is marked by a long precursor for ~300d, a rapid increase in brightness for ~60d, and then a sharp increase of ~1.6mag in only a few days to a first peak of Mr~-19.5mag. The light curve then declines rapidly until it rebrightens to a second distinct peak of Mr~-17.3mag centered at ~335d after the first peak. The spectra are dominated by Balmer lines with a complex morphology, including a narrow component with a width of ~1300km/s (first peak) and ~2500km/s (second peak) that we associate with the circumstellar medium (CSM) and a P Cygni component with an absorption velocity of ~8500km/s (first peak) and ~5600km/s (second peak) that we associate with the SN-CSM interaction shell. Using the luminosity and velocity evolution, we construct a flexible analytical model, finding two significant mass-loss episodes with peak mass loss rates of ~10 and ~5M_{sun}_/yr about 0.8 and 2yr before explosion, respectively, with a total CSM mass of ~2-4M_{sun}_. We show that the most recent mass-loss episode could explain the precursor for the year preceding the explosion. The SN ejecta mass is constrained to be ~5-30M_{sun}_ for an explosion energy of ~(3-10)x10^51^erg. We discuss eruptive massive stars (luminous blue variable, pulsational pair instability) and an extreme stellar merger with a compact object as possible progenitor channels.
Author(s): Hiramatsu D.; Matsumoto T.; Berger E.; Ransome C.; Villar V.A.; Gomez S.,Cendes Y.; De K.; Bostroem K.A.; Farah J.; Howell D.A.; McCully C.,Newsome M.; Padilla Gonzalez E.; Pellegrino C.; Suzuki A.; Terreran G.
IVOA id: ivo://cds.vizier/j/apj/964/181

r-band LCs of a doubly imaged lensed SDSS quasar

2026-08-20T09:20:44Z

Description: We analyze variability in 15-season optical lightcurves from the doubly imaged lensed quasar SDSS J165043.44+425149.3, comprising five seasons of monitoring data from the Maidanak Observatory (277 nights in total, including the two seasons of data previously presented in Vuissoz+ 2007A&A...464..845V), five seasons of overlapping data from the Mercator telescope (269 nights), and 12 seasons of monitoring data from the US Naval Observatory, Flagstaff Station at lower cadence (80 nights). We update the 2007 time-delay measurement for SDSS_J165043.44+425149.3 with these new data, finding a time delay of {Delta}t_AB_=-55.1_-3.7_^+4.0^days, with image A leading image B. We analyze the microlensing variability in these lightcurves using a Bayesian Monte Carlo technique to yield measurements of the size of the accretion disk at {lambda}_rest_=2420{AA}, finding a half-light radius of log(r1/2/cm)=16.19_-0.58_^+0.38^ assuming a 60{deg} inclination angle. This result is unchanged if we model 30% flux contamination from the broad-line region. We use the width of the MgII line in the existing Sloan Digital Sky Survey spectra to estimate the mass of this system's supermassive black hole, finding M_BH_=2.47x10^9^M_{sun}_. We confirm that the accretion disk size in this system, whose black hole mass is on the very high end of the MBH scale, is fully consistent with the existing quasar accretion disk size-black hole mass relation.
Author(s): Rivera A.B.; Morgan C.W.; Florence S.M.; Kniezewski K.; Millon M.,Courbin F.; Dahm S.E.; Vrba F.J.; Tilleman T.M.; Cornachione M.A.,Asfandiyarov I.M.; Ehgamberdiev S.A.; Burkhonov O.A.
IVOA id: ivo://cds.vizier/j/apj/964/173

HST photometry of SNe in nearby galaxies

2026-08-20T09:02:20Z

Description: Over recent decades, robotic (or highly automated) searches for supernovae (SNe) have discovered several thousand events, many of them in quite nearby galaxies (distances <30Mpc). Most of these SNe, including some of the best-studied events to date, were found before maximum brightness and have associated with them extensive follow-up photometry and spectroscopy. Some of these discoveries are so-called "SN impostors," thought to be superoutbursts of luminous blue variable stars, although possibly a new, weak class of massive-star explosions. We conducted a Snapshot program with the Hubble Space Telescope (HST) and obtained images of the sites of 31 SNe and four impostors, to acquire late-time photometry through two filters. The primary aim of this project was to reveal the origin of any lingering energy for each event, whether it is the result of radioactive decay or, in some cases, ongoing late-time interaction of the SN shock with preexisting circumstellar matter, or the presence of a light echo. Alternatively, lingering faint light at the SN position may arise from an underlying stellar population (e.g., a host star cluster, companion star, or a chance alignment). The results from this study complement and extend those from Snapshot programs by various investigators in previous HST cycles.
Author(s): Baer-Way R.; DeGraw A.; Zheng W.; Van Dyk S.D.; Filippenko A.V.; Fox O.D.,Brink T.G.; Kelly P.L.; Smith N.; Vasylyev S.S.; de Jaeger T.; Zhang K.,Stegman S.; Ross T.; Yunus S.
IVOA id: ivo://cds.vizier/j/apj/964/172

N(HI) in the local interstellar medium

2026-08-19T14:33:11Z

Description: Obtaining a complete census of gas in the local interstellar medium (LISM; <100pc) is challenging given the limited available tracers of the warm, partially ionized medium. Medium- to high-resolution UV absorption spectroscopy toward individual nearby stars is the primary method used, and incomplete spatial sampling of this complex medium makes a global map of the material difficult. Using HI column density measurements derived from HI Ly{alpha} spectroscopy toward 164 stars inside 100pc, we have generated 2D spatially interpolated N(HI) maps for different distance shells. Based on the area-weighted sky averages, we find that sight lines inside 10pc typically have log_10_(N(HI)/cm^-2^)~17.9. For greater distance shells, log_10_(N(HI)/cm^-2^) increases to 18.3 (10-20pc), then to 18.4 (20-70pc), and finally to 18.6 (70-100pc). This last increase is likely associated with the detection of the Local Bubble boundary, thus making the plateau of column density from 20 to 70pc notable and suggestive of the rarity of warm LISM material beyond ~10-20pc. We estimate that the uncertainties associated with N(HI) values inferred from the interpolated sky maps are approximately inversely correlated with the number of samples in each distance shell, and are in the range of 0.20-0.48dex, compared to the 0.01-0.30dex typically determined from direct Ly{alpha} observations. We discuss the impact of these uncertainties on interstellar medium corrections of extreme-UV and Ly{alpha} observations for nearby stars. Denser spatial sampling of the sky via UV absorption spectroscopy of nearby stars is required to improve the accuracy of these N(HI) estimates.
Author(s): Youngblood A.; France K.; Koskinen T.; Mason J.P.; Redfield S.; Wood B.E.,Bourrier V.; dos Santos L.; Johns-Krull C.; King G.W.; Linsky J.L.,Peacock S.
IVOA id: ivo://cds.vizier/j/aj/170/342

MDW Halpha Sky Survey DR1

2026-08-19T08:04:26Z

Description: The Mittelman-di Cicco-Walker (MDW) H{alpha} Sky Survey is an autonomously operated all-sky narrowband (3nm) H{alpha} imaging survey. The survey was founded by amateur astronomers, and the northern sky (decl. >=0{deg}) is presented here in its second stage of refinement for academic use. Each 3.6 deg^2^ MDW field has 12 20 minutes individual exposures with a pixel scale of 3.2", a typical point-spread function of 6", and a stack point-source depth of 16-17 mag. The northern MDW Survey Data Release 1 (DR1) includes calibrated mean and individual images, star-removed mean fields, and point-source catalogs for all images matched to Data Release 1 of the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1) and the INT Galactic Plane Survey. (All DR1 components are available at https://mdw.astro.columbia.edu. The catalogs are also made available in the AAS Journals Zenodo repository: doi:10.5281/zenodo.17307324.) Our initial study of H{alpha} filament widths finds a typical FWHM of 30"-45" in the Lyra region. The matched catalogs (with a median match distance of ~0.5"), combined with our distinctive narrowband photometry, are also used to identify H{alpha} variable and excess sources. These initial studies highlight some of the many scientific uses of the MDW H{alpha} survey.
Author(s): Aftab N.; Zhang X.; Walker S.; Di Cicco D.; Mittelman D.R.; Gupta S.,Saydjari A.K.; Putman M.; Schiminovich D.
IVOA id: ivo://cds.vizier/j/aj/171/17

Optical variability of jetted AGN

2026-08-19T07:04:18Z

Description: The variability characteristics of jetted active galactic nuclei (AGNs) serve as a powerful diagnostic tool for probing the physical mechanisms underlying accretion processes and jet formation in supermassive black holes. We used the jetted AGNs detected by the Fermi Large Area Telescope to study the origins of optical variability of jetted AGNs. Our main findings are that (1) jetted AGNs with efficient accretion exhibit significantly greater optical variability amplitudes than jetted AGNs with inefficient accretion. This result indicates that standard thin accretion disks produce stronger optical variability than advection-dominated accretion flows (ADAFs). (2) There is a significant positive correlation between optical variability amplitudes and radio luminosity, gamma-ray luminosity, X-ray luminosity, the synchrotron peak frequency luminosity, the inverse Compton peak frequency luminosity, and Compton dominance for jetted AGNs with inefficient accretion. In contrast, no significant correlation is found for jetted AGNs with efficient accretion. These results indicate that relativistic jets mainly drive the optical variability in jetted AGNs with inefficient accretion. (3) In the effective accretion mode, the variability amplitudes of jetted AGNs are inversely correlated with the accretion rate. In contrast, these amplitudes in the ineffective accretion mode are positively correlated with the accretion rate. These results suggest that in addition to relativistic jets, accretion rates also play a significant role in the optical variability of jetted AGNs with ineffective accretion. The trend of the correlation between optical amplitude and accretion rate depends on the mode of accretion.
Author(s): Chen Y.; Gudagger Q.; Fan J.; Xiong D.; Yu X.; Zhong X.; Guo X.,Ding N.; Yi T.
IVOA id: ivo://cds.vizier/j/a+a/712/a191

13 planets and brown dwarfs astrometry

2026-08-19T06:59:55Z

Description: Over the past decade, advances in high-contrast imaging instrumentation, coupled with extreme adaptive optics systems, have enabled the discovery of tens of planets and brown dwarfs orbiting at wide separations from their host stars (a>~10au). The existence of companions at these separations challenges current planet-formation paradigms, highlighting the importance of high- contrast imaging as the only technique capable of directly probing this region of planetary systems. In this paper, we present a survey of thirteen planets and brown dwarfs observed with VLT/SPHERE between June 2023 and July 2025. These data provide updated photometry in the 1.0-1.7um range and new high-precision astrometry, enabling tighter constraints on their orbital properties. We used the IRDIS subsystem to acquire dual-band H2H3 images ({lambda}_H2_=1.593um, {lambda}_H3_=1.667um) for all companions in our sample. For the three objects located within the IFS field of view (GQ Lup B, PZ Tel B, and HD 984 B), we additionally obtained low-resolution (R~50) near-infrared (0.96-1.34um) spectra. We combined our new astrometric measurements with those available in the literature to derive updated orbital solutions. The orbital fitting was performed using the orbitize! Python package. For CT Cha b, HIP 78530 B, HIP 64892 B, and RX J1609.5-2105 b, this work provides the first orbital solutions to date. We derived new photometry for all objects, which, when compared with field dwarfs in color-magnitude diagrams, indicates spectral types ranging from mid-M to mid-L. For the companions observed with IFS, their spectra are best matched by those of M6-M8.5 field dwarfs. Our updated orbital fits provide tighter constraints for nearly all companions and are consistent with non-circular orbits in all cases, potentially disfavoring core-accretion formation within their circumstellar disks.
Author(s): Bernardi A.; Zurlo A.; Lazzoni C.; Desidera S.; Mesa D.; Perez S.,Nogueira P.H.; Barbato D.; Dasgupta A.
IVOA id: ivo://cds.vizier/j/a+a/712/a190

SN 2024gy photometry and polarimetry

2026-08-18T15:15:53Z

Description: Type Ia supernovae (SNe Ia) are well-known standardisable candles, and are one of the main ways to measure the distance to their host galaxies. However, extinction due to interstellar dust causes objects to appear fainter and redder. Correcting for this requires estimating the amount of intervening material and how the extinction changes as a function of wavelength. We present and analyse optical and near-infrared data of the well-observed SN 2024gy and use these to compare different extinction estimation techniques, making use of photometric, spectroscopic, and polarimetric data. SN 2024gy is a normal SN Ia with high velocity (HV) components in SiII_{lambda}6355_ (phase<-10-days) and a particularly strong HV feature in the CaII near-infrared triplet (up to peak). Modelling SN 2024gy with TARDIS shows better matches with a double-detonation scenario compared to a delayed-detonation scenario due to a better match to the CaII HV component. A measurement of the stable Ni/Fe ratio however favours a delayed-detonation scenario. Host extinction estimates range from E(B-V)_host_=0.12+/-0.02mag (narrow interstellar absorption lines) to E(B-V)_host_=0.24+/-0.06mag (Lira law) with a mean of E(B-V)_host_=0.22+/-0.04mag, assuming R_V_=3.1. The spread between different methods highlights the challenge of accurately estimating the amount of extinction light suffers before being observed.
Author(s): Terwel J.H.; Maguire K.; O'Donnell C.; Pursiainen M.; Casasbuenas A.,Thiim Gadeberg J.; Godson B.; Harvey L.; Nobre Hauptmann B.; Koivisto N.,Liu C.; Shenoy S.; Grund Sorensen S.; Diaz Teodori M.A.; Guldberg Theil A.,Turkki M.; Alburai A.; Anderson J.; de Boer T.; Mueller Bravo T.; Burgaz U.,Chambers K.C.; Chen T.-W.; Duarte J.; Galbany L.; Gromadzki M.; Inserra C.,Johansson J.; Kim Y.-L.; Lowe T.; Magnier E.; Santos R.P.; Sollerman J.,Wainscoat R.; Young D.R.; Chen T.X.; Graham M.J.; Kasliwal M.M.,Masci F.J.; Purdum J.N.; Belkhodja I.
IVOA id: ivo://cds.vizier/j/a+a/712/a173

JWST light curves & transit depths of HAT-P-26b

2026-08-18T14:13:27Z

Description: We present the James Webb Space Telescope (JWST) transmission spectrum of the exoplanet HAT-P-26 b (18.6M_{Earth}_, 6.33R_{Earth}_), based on a single transit observed with the JWST NIRSpec G395H grating. We detect water vapor (ln(B)=4.1), carbon dioxide (ln(B)=85.6), and sulfur dioxide (ln(B)=13.5) with high confidence, along with marginal indications for hydrogen sulfide and carbon monoxide (ln(B)<0.5). The detection of SO_2_ in a warm super-Neptune-sized exoplanet (R_P_~6R_{Earth}_) bridges the gap between previous detections in hot Jupiters and sub-Neptunes, highlighting the role of disequilibrium photochemistry across a broad range of exoplanet atmospheres, including those cooler than 1000 K. Our precise measurements of carbon, oxygen, and sulfur indicate an atmospheric metallicity of ~10x solar and a subsolar C/O ratio. Retrieved molecular abundances are consistent within 2{sigma} with predictions from self-consistent models including photochemistry. The elevated CO2 abundance and possible H2S signal may also reflect sensitivities to the thermal structure, cloud properties, or additional disequilibrium processes such as vertical mixing. We compare the SO_2_ abundance in HAT-P-26 b with that of 10 other JWST-observed giant exoplanets, and find a correlation with atmospheric metallicity. The trend is consistent with the prediction from I. J. M. Crossfield, showing a steep rise in SO_2_ abundance at low metallicities, and a more gradual increase beyond 30x solar. This work is part of a series of studies by our JWST Telescope Scientist Team (JWST-TST), in which we use Guaranteed Time Observations to perform Deep Reconnaissance of Exoplanet Atmospheres through Multi-instrument Spectroscopy (DREAMS).
Author(s): Gressier A.; Batalha N.E.; Wogan N.; Alderson L.; Doud D.; Espinoza N.,MacDonald R.J.; Wakeford H.R.; Valenti J.A.; Lewis N.K.; Seager S.,Stevenson K.B.; Allen N.H.; Canas C.I.; Challener R.C.; Glidden A.,Huang J.; Lin Z.; Louie D.R.; Maguire C.; Mullens E.; Sotzen K.,Valentine D.; Clampin M.; Pueyo L.; van der Marel R.P.; Mountain C.M.
IVOA id: ivo://cds.vizier/j/aj/170/292

The eXtended Catalogue of Spectroscopic Binary Orbits

2026-08-18T14:05:52Z

Description: SBX originated from the migration of the SB9 catalogue, a project undertaken as part of Simon Alexandre's Master's thesis in Data Science at ULB in 2024/2025. This effort involved transferring the catalogue into a robust relational SQL database with well-defined constraints to guarantee data consistency and facilitate advanced querying capabilities. Enriched with high-precision astrometric data from Gaia DR3 and other external sources, SBX offers significantly improved completeness and accuracy in the positions and motions of astronomical objects. Today, the database is maintained by Simon Alexandre and Thibault Merle. A modern web interface, featuring intuitive search functions, orbital visualisations, and comprehensive data download options, has been developed to enhance accessibility and usability. The first release of SBX is online since 2025-06-24.
Author(s): Merle; T.; Jorissen; A.; Alexandre; S.; Desuter; J.; Loup; C.; Tokovinin; A.,Traven; G.; Van der Swaelmen; M.; Van Eck; S.; Van de Steene; G.,Southworth; J.; Sadowski; G.
IVOA id: ivo://cds.vizier/b/sbx

Hidden Monsters with SPHEREx. I.

2026-08-18T13:30:14Z

Description: Heavily reddened quasars (HRQs) are luminous, dust-obscured broad-line quasars thought to trace a short-lived phase of intense black hole growth and feedback. Previous studies have been limited by small sample sizes, which restricted robust statistical analyses of their properties. We expand the census of the most luminous HRQs to enable population-level studies, aiming to connect their spectral energy distributions (SEDs) to other luminous quasar populations and place them in the context of an evolutionary sequence for massive galaxy and black hole formation. We assembled multi-wavelength broadband photometry for the brightest (K_AB_<18mag) HRQ candidates and selected active galactic nucleus (AGN) candidates with red near-IR colours of (J-K)_AB_>1.6. We employed SPX spectrophotometry to confirm the HRQs and determine redshifts. Detailed SED fitting allowed us to compare these HRQs to other luminous quasar populations, including a control sample of hyper-luminous, unobscured unWISE-Gaia (Quaia) quasars, as well as luminous hot dust-obscured galaxies (hot DOGs). We confirm 76 new HRQs with redshifts of 1.5<z_sys_<3.9, dust-corrected optical continuum luminosities of log_10_({lambda}L_{lambda}(3000{AA}_[erg/s])>47.0, and line-of-sight extinctions of 0.4<E(B-V)<1.6 (A_V_~1-5mag). This more than doubles the number of confirmed HRQs at z_sys_>1.5 including the first 7 HRQs ever identified at z>3. A UV excess consistent with scattered quasar emission is detected in 76 per cent of SPX HRQs. We conclusively demonstrate that HRQs are hot-dust poor compared to blue quasars of similar luminosities and redshifts. We find that the 6um continuum luminosities of HRQs are systematically lower at fixed 3000{AA}, continuum luminosity relative to blue Quaia quasars, suggesting that HRQs are deficient in both hot and warm dust components. This combination of depleted torus-scale dust reservoirs and higher luminosities compared to hot DOGs and blue quasars supports a scenario in which HRQs represent a blow-out phase, when strong feedback has begun to clear the central regions of obscuring material.
Author(s): Stepney M.; Banerji M.; Bauer F.E.; Assef R.J.; Li G.
IVOA id: ivo://cds.vizier/j/a+a/712/a183

MiMO: 1232 Gaia DR3 open clusters param. & mass funct.

2026-08-18T12:45:53Z

Description: We present a homogeneous catalog of 1232 open clusters with precisely determined ages, metallicities, distances, extinctions, and stellar mass function (MF) slopes, derived from Gaia DR3 data. The parameters are inferred using the Mixture Model for Open clusters (MiMO), a novel Bayesian framework for modeling clusters in the color-magnitude diagram. By explicitly accounting for field-star contamination as a model component, MiMO removes the conventional need for stringent membership preselection, allowing for a more complete inclusion of member stars, and thereby enhancing both precision and robustness. Our results broadly agree with existing catalogs but offer improved precision. For each cluster, we provide the best-fit age, metallicity, distance, extinction, and MF slope, along with their full likelihood chains and photometric membership probabilities for individual stars. We further identify an "MF Prime" subsample of 163 clusters with high- quality data, for which the MF estimates are considered most reliable. The catalog and an open-source implementation of MiMO are made publicly available to the community.
Author(s): Li Lu; Shao Z.; Li Z.; Fu X.
IVOA id: ivo://cds.vizier/j/aj/170/288