J/ApJS/227/26 ATCA obs. of ground-state OH masers (Qiao+, 2016)
Accurate OH maser positions from the SPLASH pilot region.
Qiao H.-H., Walsh A.J., Green J.A., Breen S.L., Dawson J.R.,
Ellingsen S.P., Gomez J.F., Jordan C.H., Shen Z.-Q., Lowe V., Jones P.A.
<Astrophys. J. Suppl. Ser., 227, 26-26 (2016)>
=2016ApJS..227...26Q 2016ApJS..227...26Q (SIMBAD/NED BibCode)
ADC_Keywords: Masers ; Radio lines
Keywords: catalogs; ISM: molecules; masers; radio lines: ISM;
stars: AGB and post-AGB; stars: formation
Abstract:
We report on high spatial resolution observations, using the Australia
Telescope Compact Array (ATCA), of ground-state OH masers. These
observations were carried out toward 196 pointing centers previously
identified in the Southern Parkes Large-Area Survey in Hydroxyl
(SPLASH) pilot region, between Galactic longitudes of 334° and
344° and Galactic latitudes of -2° and +2°. Supplementing
our data with data from the MAGMO (Mapping the Galactic Magnetic field
through OH masers) survey, we find maser emission toward 175 of the
196 target fields. We conclude that about half of the 21 nondetections
were due to intrinsic variability. Due to the superior sensitivity of
the followup ATCA observations, and the ability to resolve nearby
sources into separate sites, we have identified 215 OH maser sites
toward the 175 fields with detections. Among these 215 OH maser sites,
111 are new detections. After comparing the positions of these 215
maser sites to the literature, we identify 122 (57%) sites associated
with evolved stars (one of which is a planetary nebula), 64 (30%) with
star formation, two sites with supernova remnants, and 27 (13%) of
unknown origin. The infrared colors of evolved star sites with
symmetric maser profiles tend to be redder than those of evolved star
sites with asymmetric maser profiles, which may indicate that
symmetric sources are generally at an earlier evolutionary stage.
Description:
Observations were conducted with the ATCA from 2013 October 24 to 29,
and 2015 January 27. At the frequency of the ground-state OH masers,
the 6A array results in a synthesized beam between 4.07"x7.41" and
5.50"x12.53". Observational pointing centers were determined based on
the Parkes OH maser detections introduced in Dawson+
(2014MNRAS.439.1596D 2014MNRAS.439.1596D).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 107 495 Details of 162 maser sites, derived from the
ATCA observations
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See also:
J/MNRAS/442/2240 : Accurate water maser positions from HOPS (Walsh+, 2014)
J/ApJS/208/11 : Red MSX Source Survey: massive protostars (Lumsden+, 2013)
J/MNRAS/427/343 : Infrared excesses of Hipparcos stars (McDonald+, 2012)
J/AJ/136/2413 : Galactic midplane Spitzer red sources (Robitaille+, 2008)
J/AJ/136/2391 : GLIMPSE Extended Green Objects catalog (Cyganowski+, 2008)
J/A+A/465/865 : OH masers towards high mass protostars (Edris+, 2007)
J/A+A/434/201 : The 35um absorption line towards 1612MHz masers (He+, 2005)
J/ApJS/160/220 : Full-polarization observations of OH masers (Fish+, 2005)
J/ApJS/155/595 : OH maser IRAS and MSX observations (Deacon+, 2004)
J/A+A/414/235 : OH maser emission from SFRs (Szymczak+, 2004)
J/A+A/366/481 : ATCA/VLA OH 1612 MHz survey. III. (Sevenster+, 2001)
J/A+AS/137/43 : OH/H2O masers database (Forster+, 1999)
J/A+AS/124/509 : ATCA/VLA OH 1612 MHz survey. II. (Sevenster+ 1997)
J/A+AS/122/79 : Galactic Bulge Region OH 1612MHz survey I. (Sevenster+ 1997)
J/A+AS/111/237 : OH detections from circumstellar shells (Lewis+, 1995)
J/A+AS/90/327 : 1612MHz OH survey of IRAS sources (te Lintel Hekkert+ 1991)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Name Maser spot identifier (1)
22- 23 I2 h RAh [16/17] Hour of Right Ascension (J2000)
25- 26 I2 min RAm Minute of Right Ascension (J2000)
28- 33 F6.3 s RAs Second of Right Ascension (J2000)
35 A1 --- DE- [-] Sign of the Declination (J2000)
36- 37 I2 deg DEd [40/50] Degree of Declination (J2000)
39- 40 I2 arcmin DEm Arcminute of Declination (J2000)
42- 46 F5.2 arcsec DEs Arcsecond of Declination (J2000)
48- 53 F6.2 Jy PFlux [0.1/114] Peak flux density of OH maser
55- 59 F5.2 Jy.km/s IFlux [0.1/78] Integrated flux density
61- 66 F6.1 km/s PkVel [-187/84] Peak velocity of OH maser
68- 73 F6.1 km/s MinVel [-188/81] Minimum velocity
75- 80 F6.1 km/s MaxVel [-185/85] Maximum velocity
82- 85 F4.2 arcsec errMin [0.03/2] Relative uncertainty in minor axis
87- 90 F4.2 arcsec errMaj [0.05/4.5] Relative uncertainty in major axis
92- 96 F5.1 deg errPA [-83/30] Relative uncertainty in position angle
98-103 A6 --- Comm Identification of each maser site (2)
105-107 A3 --- Ref Reference (3)
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Note (1): Obtained from the Galactic coordinates of the accurate positions,
followed by the frequency (1612, 1665, 1667, 1720MHz) and a letter to
denote the sequence of maser spots in the spectrum.
For each frequency, letters are assigned sequentially, based on their
peak velocities (from low to high).
Note (2): This column is formatted as "Assignment,Reason",
where "Assignment" can be as follows:
SF = star formation;
ES = evolved star;
SN = supernova remnant or
PN = planetary nebula.
U = unknown assignments.
"Reason" can be:
MMB = class II methanol maser site, based on the
Methanol Multibeam data (Caswell+ 2011MNRAS.417.1964C 2011MNRAS.417.1964C);
HOP = based on HOPS identification (Walsh+ 2014, J/MNRAS/442/2240);
RMS = based on RMS identification (Lumsden+ 2013ApJS.208...11L);
BAI = Bains+ (2009MNRAS.397.1386B 2009MNRAS.397.1386B);
CAS = Caswell (2004MNRAS.352..101C 2004MNRAS.352..101C);
CHE = Chen & Yang (2012AJ....144..104C 2012AJ....144..104C);
GRE = Greaves (2008PZP.....8...33G 2008PZP.....8...33G);
JON = Jones et al. (1982ApJ...253..208J 1982ApJ...253..208J);
LI1 = te Lintel Hekkert et al. (1991, J/A+AS/90/327);
LI2 = te Lintel Hekkert et al. (1989A&AS...78..399T 1989A&AS...78..399T);
MCD = McDonald et al. (2012, J/MNRAS/427/343);
SEV = Sevenster et al. (1997, J/A+AS/124/509);
USC = Uscanga et al. (2014MNRAS.444..217U 2014MNRAS.444..217U);
VIS = based on visual check on the GLIMPSE or WISE image together with
spectral features.
Note (3): References as follows:
S97 = Sevenster+ 1997, J/A+AS/124/509);
L91 = te Lintel Hekkert+, J/A+AS/90/327);
L89 = te Lintel Hekkert+ 1989A&AS...78..399T 1989A&AS...78..399T);
C98 = Caswell 1998MNRAS.297..215C 1998MNRAS.297..215C);
C04 = Caswell 2004MNRAS.352..101C 2004MNRAS.352..101C).
N = Sources first detected in this survey.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Jan-2017