J/A+A/542/A108 Giant molecular clouds in M33 (Gratier+, 2012)
Giant molecular clouds in the Local Group galaxy M33.
Gratier P., Braine J., Rodriguez-Fernandez N.J., Schuster K.F., Kramer C.,
Corbelli E., Combes F., Brouillet N., van der Werf P.P., Rollig M.R.
<Astron. Astrophys. 542, A108 (2012)>
=2012A&A...542A.108G 2012A&A...542A.108G
ADC_Keywords: Galaxies, nearby ; Molecular clouds
Keywords: ISM: clouds - stars: formation - galaxies: evolution - galaxies: ISM -
Local Group - galaxies: individual: M33 -
Abstract:
We present an analysis of a systematic CO(2-1) survey at 12"
resolution covering most of the Local Group spiral M33, which, at a
distance of 840kpc, is close enough for individual giant molecular
clouds (GMCs) to be identified. The goal of this work is to study the
properties of the GMCs in this subsolar metallicity galaxy. The CPROPS
(Cloud PROPertieS) algorithm was used to identify 337 GMCs in M33, the
largest sample to date for an external galaxy. The sample is used to
study the GMC luminosity function, or mass spectrum under the
assumption of a constant N(H2)/ICO ratio.
Description:
This study is based on CO(2-1) observations of M33 by the IRAM 30m
telescope. The dataset and data reduction are presented in detail in
Paper I, Gratier et al., 2010A&A...522A...3G 2010A&A...522A...3G.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 89 337 Clouds detected in CO
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See also:
J/A+A/522/A3 : M33 CO(2-1) and HI integrated intensity maps (Gratier+, 2010)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- GMC [1/337] Giant Molecular Cloud sequential number
5- 8 F4.1 --- PSNR Peak signal-to-noise ratio
11- 14 I4 arcsec oRA Offset in right ascension (1)
16- 20 I5 arcsec oDE Offset in declination (1)
22- 25 F4.1 kpc Rdist Deprojected distance from the centre of M33
27- 29 I3 pc Re ?=- Effective radius of the cloud
31- 32 I2 pc e_Re ?=- rms uncertainty on Re
34- 39 F6.1 km/s VCO Velocity of the GMC (2)
41- 44 F4.1 km/s W(CO) Linewidth (FWHM) of the GMC (2)
46- 48 F3.1 km/s e_W(CO) rms uncertainty on W(CO)
50- 53 F4.1 km/s W(HI) FWHM of the HI emission within the sky
projected cloud contour
55- 58 F4.1 km/s e_W(HI) rms uncertainty on W(HI)
60- 66 E7.2 Msun MH2 Molecular gas mass
68- 74 E7.2 Msun e_MH2 rms uncertainty on MH2
76- 82 E7.2 Msun MHI Atomic gas mass
84- 89 E6.2 Msun e_MHI rms uncertainty on MHI
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Note (1): Intensity-weighted central position expressed as an offset with
respect to the central position of M33: 01:33:50.905+30:39:35.79
Note (2): determined by a Gaussian fit to the line profile with no attempt
to correct for finite channel width.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 13-Mar-2012