J/MNRAS/442/1693ivo://CDS.VizieR/J/MNRAS/442/1693doi:10.26093/cds/vizier.74421693CDSPavlidou V.Angelakis E.Myserlis I.Blinov D.King O.G.Papadakis I.,Tassis K.Hovatta T.Pazderska B.Paleologou E.Balokovic M.,Feiler R.Fuhrmann L.Khodade P.Kus A.Kylafis N.Modi D.,Panopoulou G.Papamastorakis I.Pazderski E.Pearson T.J.Rajarshi C.,Ramaprakash A.Readhead A.C.S.Reig P.Zensus J.A.2024-08-09T20:15:18Z2015-06-11T09:29:10ZCDS support team

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

cds-question@unistra.frquasarsgamma-ray-astronomypolarimetryWe present first results from RoboPol, a novel-design optical polarimeter operating at the Skinakas Observatory in Crete. The data, taken during the 2013 May-June commissioning of the instrument, constitute a single-epoch linear polarization survey of a sample of gamma-ray-loud blazars, defined according to unbiased and objective selection criteria, easily reproducible in simulations, as well as a comparison sample of, otherwise similar, gamma-ray-quiet blazars. As such, the results of this survey are appropriate for both phenomenological population studies and for tests of theoretical population models. We have measured polarization fractions as low as 0.015 down to Rmag of 17 and as low as 0.035 down to 18mag. The hypothesis that the polarization fractions of gamma-ray-loud and gamma-ray-quiet blazars are drawn from the same distribution is rejected at the 3{sigma} level. We therefore conclude that gamma-ray-loud and gamma-ray-quiet sources have different optical polarization properties. This is the first time this statistical difference is demonstrated in optical wavelengths. The polarization fraction distributions of both samples are well described by exponential distributions with averages of <p>=6.4^+0.9^_-0.8_x10^-2^ for gamma-ray-loud blazars, and <p>=3.2^+2.0^_-1.1_x10^-2^ for gamma-ray-quiet blazars. The most probable value for the difference of the means is 3.4^+1.5^_-2.0_x10^-2^. The distribution of polarization angles is statistically consistent with being uniform.2014MNRAS.442.1693Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/442/1693CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/175/97 : CGRaBS: survey of {gamma}-ray blazar candidates (Healey+, 2008)J/ApJ/715/429 : First Fermi-LAT AGN catalog (1LAC) (Abdo+, 2010)J/ApJ/743/171 : The 2LAC catalog (Ackermann+, 2011)J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)J/ApJ/748/49 : Optical spectroscopy of 1LAC broad-line blazars (Shaw+, 2012)J/ApJ/764/135 : Spectroscopic redshifts of BL Lac objects (Shaw+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/442/1693https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/442/1693http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/442/1693https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/442/1693https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/442/1693http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/442/1693GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/442/1693/blazars (Photometric and polarization results of the RoboPol 2013 June optical polarization survey of {gamma}-ray-loud blazars and the {gamma}-ray-quiet control (table2), and additional archival information (table3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/442/1693/blazars?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/442/1693/blazars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/442/1693/blazars?GETtext/xml+votable180.050000true130.35083370.8949720.0055555555555555566/4027 4572 5154 5353 5361 6014 6067 6088 7426 7472 7653 7764 7969 8147 8175 8615 8915 9460 9566 9612 9633 9676 9998 10046 10163 10170 11153 11209 11212 11242 11430 11522-11523 11529 11552 11639 11649 11669 11686 11845 12604 12902 13353 13664 13927 15059 15211 15286 15305 15916 15969 16027 16059 16093 16113 16184 16223 16272 16281 16298 19143 19190 19370 19398 20099 20213 24980 25501 25542 25630 25677 26036 26131 26297 26303 26898 26983 27423 27472 28138-28139 28342 28517 29952 30012 30842 31407 31451 31663-31664 31773 31915 32174 32605 32621 32712 44340 44908 45011 48589 48798 48985 49037 490839.939104355462015e-24 9.939104355462015e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/442/1693?format=asciiGamma-raydefaultJ/MNRAS/442/1693/blazarsPhotometric and polarization results of the RoboPol 2013 June optical polarization survey of {gamma}-ray-loud blazars and the {gamma}-ray-quiet control (table2), and additional archival information (table3)SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameRoboPol ID ("RBPL" stands for "RoboPol")meta.id;meta.maincharRmag? R magnitudemagphot.mag;em.opt.Rfloatnullablee_Rmag? rms uncertainty on Rmagmagstat.error;phot.mag;em.opt.Rfloatnullabler_RmagOrigin of photometrymeta.ref;pos.framecharPPolarisation%phys.polarizationfloate_Prms uncertainty on P%stat.errorfloatPA[-92/82] Polarisation angle (1)degpos.posAng;phys.polarizationfloate_PA[0.4/198] rms uncertainty on PA (2)degstat.errorfloatObsDate.FFirst observation datetime.epochnullableObsDate.LLast observation datetime.epochnullableONameA common survey namemeta.idcharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainz[0.01/3.4]? Redshiftsrc.redshiftfloatnullabler_z? Reference for the redshift (5)meta.ref;pos.frameintnullableClBZCAT Class as of November 14, 2013 (3)meta.code.classcharProgOther monitoring programs (4)meta.id;instr.obstycharS15[0.01/29]? Flux density at 15GHz averaged over June-August 2013Jyphot.flux.density;em.radio.12-30GHzfloatnullablee_S15? rms uncertainty on S15Jystat.errorfloatnullablem[0/0.5]? Intrinsic modulation index as computed by Richards et al. 2011 (J/ApJS/194/29)src.var.indexfloatnullableR11meta.ref.urlintnullablee_m? Error on m (lower value)stat.errorfloatnullableE_m? Error on m (upper value)stat.error;stat.maxfloatnullableFgam?=- Flux of {gamma} photons above 100MeVm**-2.ks**-1phot.flux.density;em.gamma.hardfloatnullableGamma[1.6/3]? Spectral index {Gamma} as given in the 2FGLspect.indexfloatnullablee_Gamma[0.008/0.24]? rms uncertainty on Gammastat.errorfloatnullableVI[12/14190]? Variability index, as given in the 2FGLmeta.code;src.var.indexdoublenullableH[0/1] Flag indicating whether the source is in CGRaBS (Healey et al. 2008, J/ApJS/175/97)meta.noteint