J/AJ/165/99ivo://CDS.VizieR/J/AJ/165/99CDSRieke G.H.Engelke C.Su K.Casagrande L.2023-12-20T08:42:40Z2023-11-17T06:59:32ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frthe-sunstandard-starsvisible-astronomyspectroscopyinfrared-astronomyWe propose Sirius as an improved zero-point-defining star and calibrate its spectrum to an accuracy of ~0.6% in both the visible and infrared. This result is based on a newly derived independent calibration in the visible of similar accuracy to the previous standard one, with which it is combined. We use a large variety of approaches in the infrared to reach about three times smaller error than for previous absolute calibrations. The results in the two wavelength regimes are in agreement, providing a consistent link from the visible throughout the near- and mid-infrared. The Sirius-based zero-point at 5557.5{AA} (in vacuum) is 13.436{+/-}0.081x10^-12^W/cm^2^/{mu}m, based on the improved value for Vega of 3.473{+/-}0.018x10^-12^W/cm^2^/{mu}m and the measured magnitude difference between the two stars. At 2.1603{mu}m, the zero-point is 4.225{+/-}0.025x10^-14^W/cm^2^/{mu}m taking Sirius at a magnitude of -1.395. A jackknife analysis indicates that there are no serious systematic errors in these results. We consider selection of secondary standards that can extend the calibration over the sky. Despite more than a century in this role, normal A-stars are not suitable, although Am and Ap stars may be. G-stars older than ~1Gyr are good candidates if accurate temperatures can be measured. White dwarfs are suitable from the visible through the near-infrared, but their properties are unexplored at the necessary level at the longer infrared wavelengths, and for most facilities they are too faint there. Finally, as a further test of the calibration, we demonstrate an upgraded infrared flux method to determine accurate stellar diameters from K-band photometry.2023AJ....165...99Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/165/99CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/5 : UBV Photometry of Bright Stars (Johnson+ 1966)J/ApJS/99/135 : Rotation and Spectral Peculiarities (Abt+ 1995)J/AJ/110/275 : IR spectra of standard stars (Cohen+ 1995)J/AJ/112/2274 : Spectral irradiance calibration. VII. (Cohen+ 1996)J/A+AS/119/547 : IR photometry of ESO calibration stars (van der Bliek+ 1996)J/A+AS/131/209 : JHK(L') photometry of giant stars (Alonso+ 1998)J/AJ/126/2048 : NStars project; the Northern Sample. I. (Gray+, 2003)J/AJ/125/3311 : JHKL'M photometry of northern bright stars (Kidger+, 2003)J/A+A/411/559 : Effective temperature for 181 F-K dwarfs (Kovtyukh+, 2003)J/ApJS/150/343 : ISOCAM CVF 2.2-16.5{mu}m spectra (Engelke+, 2004)J/ApJS/154/673 : COBE DIRBE Point Source Catalog (Smith+, 2004)J/ApJ/626/446 : Effective temperature scale of FGK stars (Ramirez+, 2005)J/AJ/132/1445 : Standard calibration stars infrared spectra (Engelke+, 2006)J/MNRAS/373/781 : JHK photometry of faint standard stars (Leggett+, 2006)J/A+A/450/735 : Effective temperatures and radii of stars (Masana+, 2006)J/PASP/119/994 : MIPS 24um calibrators (Engelbracht+, 2007)J/AJ/133/2464 : Parameters and abundances of nearby giants (Luck+, 2007)J/A+A/463/671 : Rotational velocities of A-type stars. III. (Royer+, 2007)J/AJ/135/2245 : Absolute spectrum of Sun & Vega for 0.2-30um (Rieke+, 2008)J/A+A/487/373 : Spectroscopic parameters 451 HARPS-GTO stars (Sousa+, 2008)J/AJ/140/1919 : Zero point spectral energy distribution (Engelke+, 2010)J/ApJS/190/203 : 3.6 years of DIRBE NIR stellar light curves (Price+, 2010)J/PASP/124/140 : UBVRI Hp BT and VT photonic responses (Bessell+, 2012)J/ApJ/746/101 : Diameters and temperatures of AFG stars (Boyajian+, 2012)J/ApJ/761/16 : IR colors of Sun from Line-Depth Ratios (Casagrande+, 2012)J/ApJ/771/40 : Main-sequence A, F, G, and K stars photo. (Boyajian+, 2013)J/ApJ/768/25 : Spitzer & Herschel observations debris disks (Gaspar+, 2013)J/A+A/553/A95 : PCA approach stellar effective temperatures (Bermejo+, 2013)J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)J/ApJS/211/25 : Spitzer/IRS debris disk catalog. I. (Chen+, 2014)J/AJ/149/11 : Spectra of candidate standard stars in mid-IR (Sloan+, 2015)J/A+A/597/A137 : HD123999 and AlphaCen A and B OIFITS files (Kervella+, 2017)J/AJ/155/30 : Fundamental parameters of 87 stars from NPOI (Baines+, 2018)J/MNRAS/489/1753 : Masses and radii of Kepler and CoRoT targets (Yildiz+, 2019)J/AJ/162/198 : Fundamental parameters of 44 stars with NPOI (Baines+, 2021)J/AJ/161/177 : Spitzer IRAC photo. 36 JWST calibration stars (Krick+, 2021)J/ApJS/254/11 : The Spitzer Kepler Survey (SpiKeS) catalog (Werner+, 2021)J/A+A/658/A47 : Dwarf stars limb-darkening coefficients (Karovicova+, 2022)J/AJ/163/45 : IR absolute calibration. I. Calibration stars (Rieke+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/165/99https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/165/99http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/165/99https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/165/99https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/165/99http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/165/99GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/165/99/table17Calibrated spectrum of SiriusrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWaveWavelengthumem.wldoubleFluxFlux densityW.cm**-2.um**-1phot.fluxdoublee_Flux? Uncertainty in FluxW.cm**-2.um**-1stat.error;phot.fluxdoublenullableJ/AJ/165/99/table18Calibrated spectrum of the SunrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWaveWavelengthumem.wldoubleFluxFlux densityW.cm**-2.um**-1phot.fluxdoublee_Flux? Uncertainty in FluxW.cm**-2.um**-1stat.error;phot.fluxdoublenullable