FIRST PARALLAX MEASUREMENTS TOWARD A 6.7 GHz METHANOL MASER WITH THE AUSTRALIAN LONG BASELINE ARRAY—DISTANCE TO G 339.884−1.259.

We have conducted the first parallax and proper motion measurements of 6.7 GHz methanol maser emission using the Australian Long Baseline Array. The parallax of G 339.884–1.259 measured from five epochs of observations is 0.48 ± 0.08 mas, corresponding to a distance of 2.1 − 0.3 + 0.4 ?> kpc, placing it in the Scutum spiral arm. This is consistent (within the combined uncertainty) with the kinematic distance estimate for this source at 2.5 ± 0.5 kpc using the latest Solar and Galactic rotation parameters. We find from the Lyman continuum photon flux that the embedded core of the young star is of spectral type B1, demonstrating that luminous 6.7 GHz methanol masers can be associated with high-mass stars toward the lower end of the mass range.

[1]  K. Menten,et al.  The almost ubiquitous association of 6.7-GHz methanol masers with dust , 2014, 1410.6322.

[2]  Min-Gyu Song,et al.  ASTROMETRICALLY REGISTERED SIMULTANEOUS OBSERVATIONS OF THE 22 GHz H2O AND 43 GHz SiO MASERS TOWARD R LEONIS MINORIS USING KVN AND SOURCE/FREQUENCY PHASE REFERENCING , 2014, 1408.3513.

[3]  K. Menten,et al.  TRIGONOMETRIC PARALLAXES OF STAR FORMING REGIONS IN THE PERSEUS SPIRAL ARM , 2014, 1407.1609.

[4]  C. Goddi,et al.  A multiple system of high-mass YSOs surrounded by disks in NGC 7538 IRS1 - Gas dynamics on scales of 10–700 AU from CH3OH maser and NH3 thermal lines , 2014, 1404.3957.

[5]  K. Menten,et al.  Trigonometric parallaxes of star-forming regions in the Sagittarius spiral arm , 2014, 1404.4683.

[6]  M. Honma,et al.  ASTROMETRY AND SPATIO-KINEMATICS OF H2O MASERS IN THE MASSIVE STAR-FORMING REGION NGC 6334I(NORTH) WITH VERA , 2014 .

[7]  K. L. J. Rygl,et al.  TRIGONOMETRIC PARALLAXES OF HIGH MASS STAR FORMING REGIONS: THE STRUCTURE AND KINEMATICS OF THE MILKY WAY , 2014, 1401.5377.

[8]  Y. Murata,et al.  Rotating and Infalling Motion around the High-Mass Young Stellar Object Cepheus A-HW2 Observed with the Methanol Maser at 6.7 GHz , 2013, 1312.7235.

[9]  K. Menten,et al.  TRIGONOMETRIC PARALLAXES TO STAR-FORMING REGIONS WITHIN 4 kpc OF THE GALACTIC CENTER , 2013, 1312.3181.

[10]  M. J. Reid,et al.  Microarcsecond Radio Astrometry , 2013, 1312.2871.

[11]  K. Menten,et al.  PARALLAXES FOR W49N AND G048.60+0.02: DISTANT STAR FORMING REGIONS IN THE PERSEUS SPIRAL ARM , 2013, 1312.3856.

[12]  J. Dickey,et al.  H i ABSORPTION TOWARD H ii REGIONS AT SMALL GALACTIC LONGITUDES , 2013, 1308.2769.

[13]  S. Ellingsen,et al.  The first high-resolution observations of 19.9-ghz methanol masers , 2013, 1306.2393.

[14]  K. Menten,et al.  ON THE NATURE OF THE LOCAL SPIRAL ARM OF THE MILKY WAY , 2013, 1304.0526.

[15]  S. Sciences,et al.  Testing maser-based evolutionary schemes: a new search for 37.7-GHz methanol masers , 2012, 1212.3330.

[16]  T. Miyaji,et al.  Annual Parallax Distance and Secular Motion of the Water Fountain Source IRAS 18286-0959 , 2012, 1211.6207.

[17]  H. Kobayashi,et al.  Fundamental Parameters of the Milky Way Galaxy Based on VLBI Astrometry , 2012, 1211.3843.

[18]  J. Dickey,et al.  KINEMATIC DISTANCE ASSIGNMENTS WITH H i ABSORPTION , 2012 .

[19]  K. Shibata,et al.  Outer Rotation Curve of the Galaxy with VERA I: Trigonometric Parallax of IRAS 05168+3634 , 2012, 1204.4782.

[20]  R. D. Ekers,et al.  ATPMN: accurate positions and flux densities at 5 and 8 GHz for 8385 sources from the PMN survey , 2012, 1202.2625.

[21]  G. Fuller,et al.  The 6-GHz methanol multibeam maser catalogue – IV. Galactic longitudes 186°–330° including the Orion–Monoceros region , 2012, 1201.0787.

[22]  F. William,et al.  Astrometry for astrophysics : methods, models, and applications , 2012 .

[23]  N. McClure–Griffiths,et al.  Distances to southern 6.7-GHz methanol masers through H i self-absorption , 2011 .

[24]  G. Fuller,et al.  The 6-GHz methanol multibeam maser catalogue - III. Galactic longitudes 330° to 345° , 2011 .

[25]  S. Ellingsen,et al.  37 GHz METHANOL MASERS : HORSEMEN OF THE APOCALYPSE FOR THE CLASS II METHANOL MASER PHASE? , 2011, 1110.3828.

[26]  C. Goddi,et al.  Infall and outflow within 400 AU from a high-mass protostar - 3D velocity fields from methanol and water masers in AFLG 5142 , 2011, 1110.1647.

[27]  Roberto Ricci,et al.  The Australia telescope 20 GHz survey: hardware, observing strategy, and scanning survey catalog , 2011, 1109.1886.

[28]  K. Menten,et al.  The Bar and Spiral Structure Legacy (BeSSeL) Survey: Mapping the Milky Way with VLBI Astrometry† , 2011, 1102.5350.

[29]  W. Alef,et al.  DiFX-2: A More Flexible, Efficient, Robust, and Powerful Software Correlator , 2011, 1101.0885.

[30]  Chris Phillips,et al.  The LBA Calibrator Survey of Southern Compact Extragalactic Radio Sources - LCS1 , 2010, 1012.2607.

[31]  G. Fuller,et al.  The 6-GHz methanol multibeam maser catalogue – II. Galactic longitudes 6° to 20° , 2010, 1007.3050.

[32]  G. Fuller,et al.  The 6-GHz methanol multibeam maser catalogue – I. Galactic Centre region, longitudes 345° to 6° , 2010, 1002.2475.

[33]  M. F. Radioastronomie,et al.  Trigonometric parallaxes of 6.7 GHz methanol masers , 2009, 0910.0150.

[34]  K. Menten,et al.  The Formation of Massive Stars , 1998, Proceedings of the International Astronomical Union.

[35]  E. F. Arias,et al.  THE SECOND REALIZATION OF THE INTERNATIONAL CELESTIAL REFERENCE FRAME BY VERY LONG BASELINE INTERFEROMETRY , 2015 .

[36]  S. Ellingsen,et al.  12.2-GHz methanol masers towards 1.2-mm dust clumps: quantifying high-mass star formation evolutionary schemes , 2009, 0910.1223.

[37]  K. M. Menten,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. VII. G9.62+0.20 AND THE EXPANDING 3 kpc ARM , 2009, 0909.3773.

[38]  A. Deller,et al.  PRECISION SOUTHERN HEMISPHERE VLBI PULSAR ASTROMETRY. II. MEASUREMENT OF SEVEN PARALLAXES , 2009, 0906.3897.

[39]  G. A. Moellenbrock,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. VI. GALACTIC STRUCTURE, FUNDAMENTAL PARAMETERS, AND NONCIRCULAR MOTIONS , 2009, 0902.3913.

[40]  K. Menten,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. V. G23.01−0.41 AND G23.44−0.18 , 2008, 0811.0713.

[41]  Bo Zhang,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. IV. G35.20−0.74 AND G35.20−1.74 , 2008, 0811.0704.

[42]  K. Menten,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS: III. G59.7+0.1 AND W 51 IRS2 , 2008, 0811.0701.

[43]  K. Menten,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. II. CEP A AND NGC 7538 , 2008, 0811.0679.

[44]  K. Menten,et al.  TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. I. S 252 & G232.6+1.0 , 2008, 0811.0595.

[45]  M. Reid,et al.  Tropospheric Delay Calibrations for VERA , 2008 .

[46]  H. Kobayashi,et al.  Relative Astrometry of the J = 1→0, v = 1 and v = 2 SiO masers toward R leonis minoris using VERA , 2008, 0811.3820.

[47]  W. Brisken,et al.  PRECISION SOUTHERN HEMISPHERE PULSAR VLBI ASTROMETRY: TECHNIQUES AND RESULTS FOR PSR J1559–4438 , 2008, 0808.1598.

[48]  R. Dodson.  First VLBI observations of methanol maser polarisation, in G339.88-1.26 , 2008, 0804.2106.

[49]  S. Sakai,et al.  Astrometry of Galactic Star-Forming Region Sharpless 269 with VERA : Parallax Measurements and Constraint on Outer Rotation Curve , 2007, 0709.0820.

[50]  Yoshiharu Asaki,et al.  Verification of the Effectiveness of VSOP-2 Phase Referencing with a Newly Developed Simulation Tool, ARIS , 2007, 0707.0558.

[51]  K. Menten,et al.  Water Maser Motions in W3(OH) and a Determination of Its Distance , 2005, astro-ph/0512226.

[52]  K. Menten,et al.  The Distance to the Perseus Spiral Arm in the Milky Way , 2005, Science.

[53]  S. Ellingsen,et al.  Extended emission associated with young H II regions , 2004, astro-ph/0412146.

[54]  J. Lovell,et al.  Discovery of new 19.9‐GHz methanol masers in star‐forming regions , 2004, astro-ph/0407246.

[55]  C. Watson,et al.  Resolution of Distance Ambiguities of Inner Galaxy Massive Star Formation Regions. I. , 2003 .

[56]  Eric W. Greisen,et al.  AIPS, the VLA, and the VLBA , 2003 .

[57]  P. McCulloch,et al.  The Vela Pulsar’s Proper Motion and Parallax Derived from VLBI Observations , 2003, astro-ph/0302374.

[58]  C. McKee,et al.  The Formation of Massive Stars from Turbulent Cores , 2002, astro-ph/0206037.

[59]  A. Walsh,et al.  High-Resolution Mid-Infrared Imaging of G339.88–1.26 , 2001, astro-ph/0109095.

[60]  Andre Heck,et al.  Information Handling in Astronomy - Historical Vistas , 2002 .

[61]  D. Hartmann,et al.  The Milky Way in Molecular Clouds: A New Complete CO Survey , 2000, astro-ph/0009217.

[62]  J. Caswell,et al.  Methanol masers at 107.0 and 156.6 GHz , 2000 .

[63]  G. Garay,et al.  Massive Stars: Their Environment and Formation , 1999, astro-ph/9907293.

[64]  R. Treuhaft,et al.  The Proper Motion of Sagittarius A*. I. First VLBA Results , 1999, astro-ph/9905075.

[65]  R. Norris,et al.  Methanol Masers as Tracers of Circumstellar Disks , 1998, astro-ph/9806284.

[66]  Anthony J. Mannucci,et al.  A comparative study of ionospheric total electron content measurements using global ionospheric maps of GPS, TOPEX radar, and the Bent model , 1997 .

[67]  R. Norris,et al.  Continuum Emission Associated with 6.7-GHz Methanol Masers , 1995, astro-ph/9509068.

[68]  P. Godfrey,et al.  Pumping the interstellar methanol masers , 1992 .

[69]  R. Norris,et al.  Widespread strong methanol masers near H II regions , 1987 .

[70]  T. Dame,et al.  Molecular clouds and galactic spiral structure , 1980 .

[71]  N. Panagia,et al.  Some physical parameters of early-type stars , 1973 .