SiO Maser Survey of the Inner Bar of the Galactic Bulge

Publications of the Astronomical Society of Japan

Fujii, Takahiro⁷  Ita, Yoshifusa¹  Kameya, Osamu²  Izumiura, Hideyuki³  Nakada, Yoshikazu⁴  Miyazaki, Atsushi⁵  Deguchi, Shuji⁶ 

[1]Institute of Astronomy, School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Yoshinodai 3-1-1, Sagamihara, Kanagawa 229-8510

[2]VERA Project Office, National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588Mizusawa Astrogeodynamics Observatory, National Astronomical Observatory, 2-12 Hoshigaoka, Mizusawa, Iwate 023-0861

[3]Okayama Astrophysical Observatory, National Astronomical Observatory, Kamogata, Asakuchi, Okayama 719-0232

[4]Institute of Astronomy, School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015Kiso Observatory, School of Science, The University of Tokyo, Mitake, Kiso, Nagano 397-0101

[5]Nobeyama Radio Observatory, National Astronomical Observatory, Minamimaki, Minamisaku, Nagano 384-1305Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai, 200030, P.R. China

[6]Nobeyama Radio Observatory, National Astronomical Observatory, Minamimaki, Minamisaku, Nagano 384-1305

[7]VERA Project Office, National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima, Kagoshima 890-0065

关键词: "Galaxy: center";    "Galaxy: kinematics and dynamics";    masers;    "stars: AGB and post-AGB";   

DOI  :  10.1093/pasj/58.3.529

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

Wesurveyed291MSX/2 MASSinfraredobjectsinthe$$7^{circ}!imes2^{circ}$$areaofthegalacticcenterinthe43 GHzSiO$$J=1hbox{--}0v=1$$and2maserlines,obtainingaccurateradialvelocitiesof163detectedobjects.ThesurveyedareaistheregionwheretheIRAScatalogisincompleteduetocontaminationbyhighsourcedensity.TheobjectsinthepresentMSX/2 MASSsamplewerechosentohavesimilarinfraredcharacteristicstothoseofthepreviousSiO-maser-surveysamplesbasedonthecolor-selectedIRASsources.Thesamplingbasedonthe2 MASScatalogcausesabiastotheforesideobjectsofthebulgeduetoheavyobscurationbyinterstellardust;thedetectionsconsiderablyleanedonthe$$V_{mathrm{lsr}}lt;0$$side.The$$lhbox{--}V$$diagramrevealstwoconspicuousfeatures,whichwerenotpresentortenuousinthepreviousstudies:onefeatureindicatingalinearvelocityincreasewithlongitudewith$$vertlvertlt;{1lap{.}{}^{mathrm{circ}}5}$$,whichislikelytobeassociatedwiththeinnerbar,andtheotherfeaturehavingconsiderablyeccentricvelocities,morethanthoseofthenormal$$x_1$$-orbitfamilyfeature.Theextinction-corrected$$K$$magnitudes(ifusedasadistancemodulus)tendtoshowasequentialdepositionoftheseobjectsalongthelineofsighttowardthegalacticcenter,dependingontheirradialvelocities.Thetendencythatappearedinthedistancemeasuresisconsistentwiththebulge–bardynamicalmodelutilizingtheperiodicorbitfamiliesinthebarpotential.

【 授权许可】

Unknown