J/AZh/91/503ivo://CDS.VizieR/J/AZh/91/503CDSPynzar' A.V.Shishov V.I.2026-01-13T20:30:14Z2014-09-17T13:57:57ZCDS support team

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

cds-question@unistra.frradio-sourcesUsing literature data on approximately 400 compact radio sources detected with the Very Large Array and located in the direction of the Galactic center within 2{deg} of the compact source Sgr A*, 69 sources whose angular sizes are determined by scattering on electron density inhomogeneities were distinguished. Fifty-five of these are extragalactic, two are supercompact HII regions, ten are sources of maser emission, and two are variable Galactic sources. The excess of the apparent angular sizes of maser sources within 2{deg} of the Galactic center above the mean size of objects of this class in other parts of the Galaxy found in many studies cannot be explained purely by the effect of scattering of their radio emission on interstellar plasma inhomogeneities. The angular sizes of these objects are increased due to scattering only within Galactic longitudes of about 0.4{deg} and Galactic latitudes less than 0.1{deg}. The turbulent medium responsible for scattering of radio emission of compact sources in the immediate vicinity of the Galactic center is strongly concentrated toward the compact source Sgr A* at the Galactic center. No extragalactic sources are observed within 0.4{deg} in longitude and 0.2{deg} in latitude of the Galactic center, because of their low brightness due to the superstrong scattering in this region. Data on scatter broadening can be used to study the distribution of turbulent plasma near the Galactic center.2014AZh....91..503Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AZh/91/503CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/118/201 : Galactic Center 6 and 20cm survey (Lazio+, 1998)J/AJ/128/1646 : The Galactic Center region at 330MHz (Nord+, 2004)J/ApJS/174/481 : 2LC Compact Radio Sources in Galactic center (Lazio+, 2008)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AZh/91/503https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AZh/91/503http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AZh/91/503https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AZh/91/503https://vizier.iucaa.in/viz-bin/votable?-source=J/AZh/91/503http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AZh/91/503GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AZh/91/503/table1 (Parameters of the sources and the line-of-sight interstellar medium)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AZh/91/503/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AZh/91/503/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AZh/91/503/table1?GETtext/xml+votable180.050000true265.32125-30.39191670.005555555555555556Cone search capability for table J/AZh/91/503/table2 (Parameters of the Galactic sources and the line-of-sight interstellar medium)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AZh/91/503/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AZh/91/503/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AZh/91/503/table2?GETtext/xml+votable180.050000true264.78199-29.067950.0055555555555555565/7206-7207 6/28822 28848-28849 28852-28853 28874https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AZh/91/503?format=asciiRadiodefaultJ/AZh/91/503/table1Parameters of the sources and the line-of-sight interstellar mediumSeq[1/119] Sequential numbermeta.recordintn_Seq[*] Note on individual sources (4)meta.notecharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latfloatSimbadNameSimbad column added by the CDSmeta.idnullabletheta1? 0.33GHz observed angular size (FWHM)arcsecphys.angSizefloatnullablel_theta2Limit flag on theta2 (2)meta.code.errorchartheta2? 1.4GHz observed angular size (FWHM)arcsecphys.angSizefloatnullablel_theta3Limit flag on theta2 (2)meta.code.errorchartheta31GHz observed angular size (FWHM) (1)arcsecphys.angSizefloatEMBackground emission measurepc.cm**-3instr.backgroundintalpha? Spectral index {alpha} (S_nu_{prop.to}nu^{alpha}^)spect.indexfloatnullablee_alpha? rms uncertainty on alphastat.error;pos.eq.rafloatnullableIR.refReference to studies in which infrared sources were detected toward the radio source, in refs.dat filemeta.ref;pos.framecharTypeNature of the source (3)src.classchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/AZh/91/503/table2Parameters of the Galactic sources and the line-of-sight interstellar mediumSimbadNameSimbad column added by the CDSmeta.idnullable_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.raindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decindexedSeq[1/26] Sequential numbermeta.recordintNameNamemeta.id;meta.maincharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.lattheta? Observed angular size at frequency Freq (FWHM)arcsecphys.angSizefloatnullabletheta2? Observed angular size at frequency Freq (FWHM)arcsecphys.angSizefloatnullableFreq[1612/1720]? Observing frequencyMHzem.freqintnullabletheta3? Observed angular size reduced to 1GHz (1)arcsecphys.angSizefloatnullabletheta4? Observed angular size reduced to 1GHz (1)arcsecphys.angSizefloatnullableEMBackground emission measurepc.cm**-3instr.backgroundintRefReference to the source data, in refs.dat filemeta.ref;pos.frameintJ/AZh/91/503/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference codemeta.note;meta.mainintprimaryBibCodeBibCodemeta.bib.bibcodecharAutAuthor's namemeta.bib.authorcharComCommentsmeta.notechar