J/ApJ/802/69ivo://CDS.VizieR/J/ApJ/802/69doi:10.26093/cds/vizier.18020069CDSBower G.C.Markoff S.Dexter J.Gurwell M.A.Moran J.M.Brunthaler A.,Falcke H.Fragile P.C.Maitra D.Marrone D.Peck A.Rushton A.,Wright M.C.H.2017-07-06T06:25:30Z2015-08-27T13:14:19ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleiaccretionmilky-way-galaxyradio-continuum-emissionmillimeter-astronomysubmillimeter-astronomyWe report new observations with the Very Large Array, Atacama Large Millimeter Array, and Submillimeter Array at frequencies from 1.0 to 355GHz of the Galactic Center black hole, Sagittarius A*. These observations were conducted between 2012 October and 2014 November. While we see variability over the whole spectrum with an amplitude as large as a factor of 2 at millimeter wavelengths, we find no evidence for a change in the mean flux density or spectrum of Sgr A* that can be attributed to interaction with the G2 source. The absence of a bow shock at low frequencies is consistent with a cross-sectional area for G2 that is less than 2x10^29^cm2. This result fits with several model predictions including a magnetically arrested cloud, a pressure-confined stellar wind, and a stellar photosphere of a binary merger. There is no evidence for enhanced accretion onto the black hole driving greater jet and/or accretion flow emission. Finally, we measure the millimeter wavelength spectral index of Sgr A* to be flat; combined with previous measurements, this suggests that there is no spectral break between 230 and 690GHz. The emission region is thus likely in a transition between optically thick and thin at these frequencies and requires a mix of lepton distributions with varying temperatures consistent with stratification.2015ApJ...802...69Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/802/69CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/802/69https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/802/69http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/802/69https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/802/69https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/802/69http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/802/69GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap1.4444831663271462e-22 2.2621401108608354e-22RadiodefaultJ/ApJ/802/69/table6SMA results (Hawaii) of Sgr A*recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsDate of the observation (2013/2014)stime.epochnullableFreq[213.2/356.2] FrequencyGHzem.freqfloatSSgrA*[1.9/6.1] Sgr A* flux densityJyphot.flux.density;em.radiofloate_SSgrA*[0.1/0.5] Uncertainty in SSgrA*Jystat.errorfloatSJ1733[0.6/1.7] J1733-130 flux densityJyphot.flux.density;em.radiofloate_SJ1733[0.06/0.4] Uncertainty in SJ1733Jystat.errorfloatJ/ApJ/802/69/table3VLA results of Sgr A*recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDateDate of the observation (2012/2014)time.epochnullableFreq[1.5/41] FrequencyGHzem.freqfloatS[0.5/2]? Mean flux densityJyphot.flux.density;em.radiofloatnullablee_S[0.002/0.3]? Uncertainty in FluxJystat.errorfloatnullableDelS[-0.5/0.6] Flux density excessJyphot.flux;arith.ratiofloate_DelS[0.001/1.1] Uncertainty in DelSJystat.errorfloatJ/ApJ/802/69/table5ALMA results of Sgr A*, J1427-421, J1700-261, J1733-130recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDateDate of the observation (2013/2014)time.epochnullableIDSource identifiermeta.id;meta.maincharS218.0[0.7/4.7]? The 218.0GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS220.0? The 220.0GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS231.9? The 231.9GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS233.8[0.7/4.8]? The 233.8GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS341.6? The 341.6GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS343.6? The 343.6GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS351.7? The 351.7GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullableS353.6[0.5/4.6]? The 353.6GHz flux densityJyphot.flux.density;em.mm.200-400GHzfloatnullable