J/ApJ/906/10ivo://CDS.VizieR/J/ApJ/906/10doi:10.26093/cds/vizier.19060010CDSEgron E.Pellizzoni A.Righini S.Giroletti M.Koljonen K.,Pottschmidt K.Trushkin S.Lobina J.Pilia M.Wilms J.Corbel S.,Grinberg V.Loru S.Trois A.Rodriguez J.Lahteenmaki A.Tornikoski M.,Enestam S.Jarvela E.2022-06-13T09:58:55Z2022-05-31T06:48:55ZCDS support team

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

cds-question@unistra.frquasarsradio-sourcesradio-spectroscopyThe microquasar Cygnus X-3 underwent a giant radio flare in 2017 April, reaching a maximum flux of ~16.5Jy at 8.5GHz. We present results from a long monitoring campaign carried out with Medicina at 8.5, 18.6, and 24.1GHz, parallel to the Metsahovi radio telescope at 37GHz, from 2017 April 4 to 11. We observe a spectral steepening from {alpha}=0.2 to 0.5 (with S_{nu}_{prop}{nu}^-{alpha}^) within 6hr of the epoch of the flare's peak maximum, and rapid changes in the spectral slope in the following days during brief enhanced emission episodes while the general trend of the radio flux density indicated the decay of the giant flare. We further study the radio orbital modulation of CygX-3 emission associated with the 2017 giant flare and with six mini-flares observed in 1983, 1985, 1994, 1995, 2002, and 2016. The enhanced emission episodes observed during the decline of the giant flare at 8.5GHz coincide with the orbital phase {phi}~0.5 (orbital inferior conjunction). On the other hand, the light curves of the mini-flares observed at 15-22GHz peak at {phi}~0, except for the 2016 light curve, which is shifted 0.5w.r.t. the other ones. We attribute the apparent phase shift to the variable location of the emitting region along the bent jet. This might be explained by the different accretion states of the flaring episodes (the 2016 mini-flare occurred in the hypersoft X-ray state).2021ApJ...906...10Ehttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/906/10CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+AS/132/305 : Extragal. radio sources at 22, 37 & 87GHz (Terasranta+ 1998)J/MNRAS/406/307 : Radio variations of Cygnus X-3 (Koljonen+, 2010)J/A+A/551/A32 : Catching the radio flare in CTA 102 (Fromm+, 2013)J/MNRAS/467/L31 : SS Cyg rapid radio flaring in 2016 (Mooley+, 2017)http://www.med.ira.inaf.it/ : Medicina Radio Astronomical Station webpagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/906/10https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/906/10http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/906/10https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/906/10https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/906/10http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/906/10GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapMillimeterRadiodefaultJ/ApJ/906/10/fig1Combined table from original tablesFluxFluxJyphot.flux.density;em.radiofloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDModified Julian Date of observation, JD-2400000.5dtime.epochdoubleBandInstrument and band used for observationsinstr.bandwidthchare_FluxFlux uncertaintyJystat.error;phot.fluxfloat