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J/ApJ/702/1615       CH3OH maser survey of EGOs       (Cyganowski+, 2009)

A class I and class II CH3 OH maser survey of EGOs from the GLIMPSE survey. Cyganowski C.J., Brogan C.L., Hunter T.R., Churchwell E. <Astrophys. J., 702, 1615-1647 (2009)> =2009ApJ...702.1615C
ADC_Keywords: Masers ; Radio lines ; Interferometry Keywords: infrared: stars - ISM: jets and outflows - masers - stars: formation - techniques: interferometric Abstract: We present the results of a high angular resolution Very Large Array (VLA) Class I 44GHz and Class II 6.7GHz CH3OH maser survey of a sample of ∼20 massive young stellar object (MYSO) outflow candidates selected on the basis of extended 4.5um emission in Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire images. These 4.5um selected candidates are referred to as extended green objects (EGOs), for the common coding of this band as green in three-color Infrared Array Camera images. The detection rate of 6.7GHz Class II CH3OH masers, which are associated exclusively with massive YSOs, toward EGOs is ≳64% - nearly double the detection rate of surveys using other MYSO selection criteria. The detection rate of Class I 44GHz CH3OH masers, which trace molecular outflows, is ∼89% toward EGOs associated with 6.7GHz CH3OH masers. Description: The fixed-frequency 6.7GHz EVLA (Expanded Very Large Array) observations at the NRAO were obtained on 2008 February 1 in the B configuration and 2008 February 9, 17, and 19 in the CnB configuration: 13 EVLA antennas were available for these observations. Our 44GHz VLA observations, of the 18 EGOs observed with fixed frequency at 6.7GHz plus G11.92-0.61, were obtained on 2008 February 16 and 18 in the CnB configuration, in fixed frequency mode: 26 antennas were available for these observations. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file sample.dat 97 22 Extended Green Objects (EGO) sample (table 5 and positions from table 4) table7.dat 69 1206 Fitted properties: 6.7GHz masers table8.dat 69 1524 Fitted properties: 44GHz masers
See also: J/AJ/136/2391 : GLIMPSE Extended Green Objects catalog (Cyganowski+, 2008) J/ApJS/155/149 : CH3OH 70-61 A+ maser sources (Kurtz+, 2004) Byte-by-byte Description of file: sample.dat
Bytes Format Units Label Explanations
1- 11 A11 --- EGO Extended Green Object name (GLL.ll+B.bb) 13- 14 I2 h RAh VLA Hour of right ascension (J2000) (1) 16- 17 I2 min RAm VLA Minute of right ascension (J2000) (1) 19- 22 F4.1 s RAs VLA Second of right ascension (J2000) (1) 24 A1 --- DE- VLA Sign of declination (J2000) (1) 25- 26 I2 deg DEd VLA Degree of declination (J2000) (1) 28- 29 I2 arcmin DEm VLA Arcminute of declination (J2000) (1) 31- 34 F4.1 arcsec DEs VLA Arcsecond of declination (J2000) (1) 35 A1 --- n_EGO [g] Source not targeted (2) 37- 38 I2 h RAIh ? 24um Hour of right ascension (J2000) (3) 40- 41 I2 min RAIm ? 24um Minute of right ascension (J2000) (3) 43- 46 F4.1 s RAIs ? 24um Second of right ascension (J2000) (3) 48 A1 --- DEI- 24um Sign of declination (J2000) (3) 49- 50 I2 deg DEId ? 24um Degree of declination (J2000) (3) 52- 53 I2 arcmin DEIm ? 24um Arcminute of declination (J2000) (3) 55- 56 I2 arcsec DEIs ? 24um Arcsecond of declination (J2000) (3) 57 A1 --- n_24 [cfh ] Flag on 24um source (4) 59- 62 F4.1 Jy Flux ? Integrated MIPS 24um flux density from Cyganowski et al. (2008, Cat. J/AJ/136/2391) unless otherwise noted 64 A1 --- leFlux Limit flag on e_Flux 65- 67 F3.1 Jy e_Flux ? Flux density uncertainty 68 A1 --- f_Flux [cde ] Flag on Flux (4) 70- 97 A28 MJy/sr Contour Contour levels (in figure 1)
Note (1): Coordinates from phase tracking centers of the VLA observations (Section 2.1). In some cases, these differ slightly from the positions in Cyganowski et al. (2008, Cat. J/AJ/136/2391). Note (2): g = EGO not targeted in our survey but within VLA primary beam (6.7' FHWP) at 6.7GHz. The positions given are the EGO positions from Cyganowski et al. (2008, Cat. J/AJ/136/2391), not the VLA pointing center. Note (3): MIPS 24um counterpart position estimated, using ds9 regions, as the center of a circle around the most prominent Airy ring for each 24um source. We employ this method because it can be applied consistently for all sources. Estimated uncertainties are ∼1" for isolated, unsaturated sources, up to ∼2"-4" for blended and saturated sources (based on comparison with centroids generated by the modified "iracworks" program, see note (e)). Note (4): Flag as follows: c = No discrete 24um counterpart. d = Probable EGO counterpart is blended with other 24um source(s) and/or diffuse emission that may or may not be associated with the EGO, precluding a reliable flux estimate. e = Source is saturated. Flux was estimated using a modified version of the "iracworks" saturated source software contributed by Tom Jarrett and available at http://spider.ipac.caltech.edu/staff/jarrett/irac/tools/. The software fits the PSF wings of a source whose core is saturated, and was modified by Katherine Johnston and Remy Indebetouw to operate on MIPS 24um data. Uncertainty in the reported flux is estimated to be 20%. f = Position of the northern of two blended 24um sources (see Figure 1(j)), the probable EGO counterpart. h = Nearest 24um source, see Figure 1(s). It is unclear whether or not this MIPS source is associated with the EGO to its west.
Byte-by-byte Description of file: table[78].dat
Bytes Format Units Label Explanations
1- 11 A11 --- EGO Field Name (GLL.ll+B.bb); Target EGO 13- 14 I2 h RAh Hour of Right Ascension (J2000) 16- 17 I2 min RAm Minute of Right Ascension (J2000) 19- 24 F6.3 s RAs Second of Right Ascension (J2000) 26- 30 F5.3 arcsec e_RAs Uncertainty in RAs 32 A1 --- DE- Sign of the Declination (J2000) 33- 34 I2 deg DEd Degree of Declination (J2000) 36- 37 I2 arcmin DEm Arcminute of Declination (J2000) 39- 44 F6.3 arcsec DEs Arcsecond of Declination (J2000) 46- 50 F5.3 arcsec e_DEs Uncertainty in DEs 52- 57 F6.2 Jy Int Intensity at 6.7GHz or 44GHz in units of Jy/beam (1) 59- 62 F4.2 Jy e_Int Uncertainty in Int 64- 69 F6.2 km/s Vel LSR Velocity
Note (1): * For table 7 (6.7GHz masers): TB(K)=7794*I(Jy/beam)*(3.5313)/(θmajmin) where θmaj and θmin are the dimensions of the synthesized beam in arcseconds from Table 1 (3.5313 square arcseconds is the median value of θmajmin for the 6.7GHz observations). * For table 8 (44GHz masers): TB(K)=2198*I(Jy/beam)*(0.2867)/(θmajmin) where θmaj and θmin are the dimensions of the synthesized beam in arcseconds from Table 2 (0.2867 square arcseconds is the median value of θmajmin for the 44GHz observations).
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 10-Oct-2011
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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