J/MNRAS/505/1954ivo://CDS.VizieR/J/MNRAS/505/1954doi:10.26093/cds/vizier.75051954CDSZhu S.F.Timlin J.D.Brandt W.N.2025-07-18T20:17:01Z2024-06-15T18:59:30ZCDS support team

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

cds-question@unistra.frblack-holesactive-galactic-nucleiquasarsredshiftedphotometryspectroscopyx-ray-sourcesultraviolet-astronomyvisible-astronomyradio-sourcesWe present X-ray spectral and long-term variability analyses of an unbiased sample of 361 optically selected radio-loud quasars (RLQs) utilizing sensitive serendipitous X-ray data from the Chandra and XMM-Newton archives. The spectral and temporal properties of RLQs are compared with those of radio-quiet quasars (RQQs) matched in L2500 {AA} and z. The median power-law photon index ({gamma}) of RLQs is 1.84_-0.01_^+0.01^, which is close to that of matched RQQs (1.90_-0.01_^+0.02^). No significant correlations between {gamma} and radio-loudness, Lx/L_x,rqq_ (the X-ray luminosity over that expected from the Lx-Luv relation for RQQs), redshift, or Eddington ratio are found for our RLQs. The stacked X-ray spectra of our RLQs show strong iron-line emission and a possible Compton-reflection hump. The intrinsic X-ray variability amplitude is ~= 40 per cent for RLQs on time-scales of months-to-years in the rest frame, which is somewhat smaller than for the matched RQQs (~= 60 per cent) on similar time- scales, perhaps due to the larger black hole masses and lower Eddington ratios in our RLQ sample. The X-ray spectral and variability results for our RLQs generally support the idea that the X-ray emission of typical RLQs is dominated by the disc/corona, as is also indicated by a recent luminosity correlation study.2021MNRAS.505.1954Zhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/505/1954CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/496/245 : L_x_-L_uv_-L_radio_ relation in radio-loud quasarsJ/MNRAS/498/4033 : Extreme quasar X-ray variability (Timlin+, 2020)J/ApJ/726/20 : X-ray emission from quasars (Miller+, 2011)VII/286 : SDSS quasar catalog, fourteenth data release (Paris+,2018)IX/57 : The Chandra Source Catalog (CSC), Release 2.0 (Evans+,2019)IX/55 : XMM-Newton Serendipitous Source Catalogue 3XMM-DR8https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/505/1954https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/505/1954http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/505/1954https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/505/1954https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/505/1954http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/505/1954GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/505/1954/table1 (*The RLQ used in this paper)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/505/1954/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/505/1954/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/505/1954/table1?GETtext/xml+votable180.050000true1.175750.00647220.005555555555555556Cone search capability for table J/MNRAS/505/1954/tablea1 (*The RQQ used in this paper)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/505/1954/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/505/1954/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/505/1954/tablea1?GETtext/xml+votable180.050000true1.6487083-0.12250.0055555555555555565/2628 6814 6/32 4168 4178 4298 4303 4313 4327 4348 4361 4376 4391 4397 4447-4448 4504 4512 4536 4548 4577 4689 4720 4750 4758 4780 4801 4804 4808 4831 4835 4838-4839 4850 4943 4947 4955 4964-4965 4992 5027 5051 5061 5069 5091 5099 5140 5244 5299 5305-5306 5311 5327 5351 5363 5405 5437 5469 5491 5506 5523 5536 5545 5569 5587-5588 5610 5625 5628 5630 5664 5675 5689 5711 5731-5733 5751 5762 5795 5797 5807 5816 5818 5864 5881 5927 5936 5975 5985 5999-6000 6008 6033-6034 6046-6048 6069 6071 6073 6075 6077 6086 6090 6098 6111-6112 6115 6172 6337 6399 6428 6431 6448 6470-6471 6494 6538 6551 6623 6629 6639 6977 7168 7178 7220 7225 7237 7239 7241-7242 7264 7267 7273 7278 7308 7371 7424-7426 7446 7459 7477 7606 8195 8201 8220 8271 8338-8339 8507 8524 8553 8555 8650 8671 8675 8681 8705 8707 8733 8740 8906 8909 8920 8969 8972 9036 9145-9148 9150-9151 9181 9271 9328 9343 9354 9373 9379 9428 9466 9470 9476 9496 9498 9604 9613 9615 9618 9764 9769 9825 9842 9992 9997 9999 10137 10153-10154 10158 10189 10213 10261 10271 10306-10307 10312-10313 10318 10336-10338 10378-10379 10391 10396 10400-10401 10420 10442 10451 10464 10484 10516-10518 10529 10544 10551 10587 10589 10599-10601 10637 10657 10663 10700 10704-10705 10707 10721 10743 10769 10901 10905 10911 10963 10970 10979 10999 11026 11029 11042 11044 11063 11080 11101 11111 11117 11127 11147 11179 11191 11204 11214 11217 11222 11237 11252-11253 11259 11279 11290 11293 11302 11371-11372 11388 11392 11424-11425 11428 11430 11434 11457 11467 11566 11776 11806 11813 11845 11933 11940 17237 17406 17469 17492 17497 17506 17622-17623 17662 17666 17683 17688-17690 17695 17699 17702 17719 17741 17749 17755 17761 17766-17767 17769 17772-17773 17781 17804 17812 17815 17817 17850 17860 18005-18007 18009 18016 18019 18022-18024 18028 18060 18071 18084 18089-18090 18096 18110 18112 18153 18184 18242 18274 18385 18416 18546 18627 18682 18762 18779-18780 18783 18790-18791 18795-18796 18800 18826-18827 18889 19028 19033 19036 19062 19089 19091 19097 19216 19218 19432 19458 19493 19504 19846 19935 19950 20073 20075 20292 21887 23210 23216 25585 25906 25944 25950 25956 25958 25977 25981 25990-25991 26022 26039 26056 26103 26157 26175 26186 26189 26195 26208-26209 26223 26280 26292 26298 26302-26303 26313 26316 26331 26365 26420-26421 26427 26446 26470 26508 26555 26596 26946 26967 26975 26990 27049 27100 27127-27128 27216 27225 27235 27238 27241 27245 27247 27305 27307 27310 27318 27343-27344 27382-27383 27392 27402 27423 27428 27440 27462 27474 27476 27514-27515 27524 27537 27541 27580 27617 27664 27676 27681 27718-27719 27728 27736 27739 27761-27763 27767 27773 27862 27906 27914 27918 27921 27929 27936 27941-27942 27944 27946 27948 27963 28022 28032 28045 28060 28080 28086 28127 28141 28149 28173-28174 28184 28209 28251 28275 28357 28377 28391 28393 28397 28430 28448 28452 28471 28492 28515 28535 28542 28555 28589 28609 28619-28620 31332 31354 31663 31668 32447 32500 36765 36779 36782 36785 36793 36846 40957 45044 45054 49106https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/505/1954?format=asciiX-rayUVOpticalRadiodefaultJ/MNRAS/505/1954/table1*The RLQ used in this paperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS-DR14 designation (HHMMSS.ss+DDMMSS.s) (Name) (G1)meta.id;meta.maincharzRedshift normally heliocentric (z)src.redshiftfloatimagThe i-band magnitude (mi) (1)magphot.mag;em.opt.IdoubleSimbadNameSimbad column added by the CDSmeta.idcharnullablelogL2500ALogarithm of the rest-frame monochromatic luminosity at 2500 {AA} (logL2500A)log(1e-07W.Hz**-1)phys.luminosity;em.UVdoublelogL5GHzLogarithm of the rest-frame monochromatic luminosity at 5GHz (logL5GHz)log(1e-07W.Hz**-1)phys.luminosity;em.radiodoublelogL2keVLogarithm of the rest-frame monochromatic luminosity at 2keV (logL2keV)log(1e-07W.Hz**-1)phys.luminosity;em.X-rayfloatlogRLogarithm of the radio loudness parameter R (logR) (2)phot.flux;arith.ratiodoublealphaR? Radio spectral slope, -d(Log F)/d(Log nu) (alphaR)spect.indexdoublenullablelog(Lx/Lxrqq)Logarithm of X-ray luminosity ratio (3)phys.luminosity;arith.ratiodouble_RAPositions from SDSS name (right ascension part)degpos.eq.ra;meta.main_DEPositions from SDSS name (declination part)degpos.eq.dec;meta.mainJ/MNRAS/505/1954/table2The RLQ X-ray observationsObsObservation start date (MJD)stime.start;obsdoubleEcstatThe expectation number of cstat (Ecstat) (G6)meta.numberdoubles_cstatThe standard deviation of cstat (Scstat) (G6)stat.stdevdoubleObsIDObjet identifier (ObsID)meta.id;obscharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS-DR14 designation SDSS J (HHMMSS.ss+DDMMSS.s) (Name) (G1)meta.id;meta.maincharInstThe instrument used for the observation, ACIS for Chandra and pn/MOS1/MOS2 for XMM-Newton observations (Inst) (G2)instr.setupcharlogfdetLogarithm of the detection flux limit in the 0.5-7 keV band at the position of the quasar on the detector expressed in erg/cm^2^/s (logfdet) (G3)log(mW.m**-2)phot.flux;em.X-raydoubleCTnetThe net source counts (G4)ctphot.count;em.X-raydoubleS/NSignal to noise ratio, S/N = net/sqrt(s+b/k^2^) (SNR)stat.snrdoublelogfxLogarithm of the energy flux in the 0.5-7 keV band if the the quasar is detected expressed in erg/cm^2^/s (logfx) (G5)log(mW.m**-2)phot.flux;em.X-raydoublef_logfx[0 1] Detection flag in the X-ray observation, takes 1 if it's the case 0 otherwise (xdet)meta.codeintgamma? The power-law photon index derived from our spectral fitting, it is not estimated for non-detection cases(gamma)spect.indexdoublenullablee_gamma? Lower error on gamma (gammaLo)stat.errordoublenullableE_gamma? Upper error on gamma (gammaHi)stat.error;stat.maxdoublenullablecstatThe statistic number of the fit (cstat) (G6)meta.numberdoubleJ/MNRAS/505/1954/tablea1*The RQQ used in this paperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS-DR14 designation source (HHMMSS.ss+DDMMSS.s) (Name) (G1)meta.id;meta.maincharzRedshift normally heliocentric (z)src.redshiftdoubleimagThe i-band magnitude (mi)magphot.mag;em.opt.IfloatlogL2500ALogarithm of the rest-frame monochromatic luminosity at 2500 {AA} (logL2500A)log(1e-07W.Hz**-1)phys.luminosity;em.UVdouble_RAPositions from SDSS name (right ascension part)degpos.eq.ra;meta.main_DEPositions from SDSS name (declination part)degpos.eq.dec;meta.mainSimbadNameSimbad column added by the CDSmeta.idcharnullableJ/MNRAS/505/1954/tablea2The RQQ X-ray observationsS/NSignal to noise ratio, S/N = net/sqrt(s+b/k^2^) (SNR)stat.snrdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS-DR14 designation (HHMMSS.ss+DDMMSS.s) (Name) (G1)meta.id;meta.maincharObsIDObjet identifier (ObsID)meta.id;obscharObsObservation start date (MJD)stime.epochdoubleInstThe instrument used for the observation, ACIS for Chandra observations (Inst) (G2)instr.setupcharlogfdetLogarithm of the detection flux limit in the 0.5-7 keV band at the position of the quasar on the detector expressed in erg/cm^2^/s (logfdet) (G3)log(mW.m**-2)phot.flux;em.X-raydoubleCTnetThe net source counts (G4)ctphot.count;em.X-raydoublelogfx? Logarithm of the energy flux in the 0.5-7 keV band if the the quasar, is detected, expressed in erg/cm^2^/s (logfx) (G5)log(mW.m**-2)phot.flux;em.X-raydoublenullablef_logfx[0 1] Detection flag in the X-ray observation, takes 1 if it's the case 0 otherwise (xdet)meta.codeintgamma? The power-law photon index derived from our spectral fitting it is not estimated for cases of non-detection (gamma)spect.indexdoublenullablee_gamma? Lower error on gamma (gammaLo)stat.errordoublenullableE_gamma? Upper error on gamma (gammaHi)stat.error;stat.maxdoublenullablecstatThe statistic number of the fit (cstat) (G6)meta.numberdoubleEcstatThe expectation number of cstat (Ecstat) (G6)meta.numberdoubles_cstatThe standard deviation of cstat (Scstat) (G6)stat.stdevdouble