J/MNRAS/517/2990 ∼1000 RC sources in M33 with the VLA (Tabatabaei+, 2022)
Cloud-scale radio surveys of star formation and feedback in Triangulum
Galaxy M 33 VLA observations.
Tabatabaei F.S., Cotton W., Schinnerer E., Beck R., Brunthaler A.,
Menten K.M., Braine J., Corbelli E., Kramer C., Beckman J.E., Knapen J.H.,
Paladino R., Koch E., Camps-farina A.
<Mon. Not. R. Astron. Soc. 517, 2990-3007 (2022)>
=2022MNRAS.517.2990T 2022MNRAS.517.2990T (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies ; Radio continuum ; Radio sources ; Interferometry ;
Interstellar medium ; Photometry ; Positional data
Keywords: radiation mechanisms: non-thermal - ISM: magnetic fields -
(ISM:) cosmic rays; galaxies: individual: M 33 -
galaxies: star formation - radio continuum: ISM
Abstract:
Studying the interplay between massive star formation and the
interstellar medium (ISM) is paramount to understand the evolution of
galaxies. Radio continuum (RC) emission serves as an extinction-free
tracer of both massive star formation and the energetic components of
the ISM. We present a multiband RC survey of the Local Group galaxy M
33 down to ~=30 pc linear resolution observed with the Karl G. Jansky
Very Large Array (VLA). We calibrate the star formation rate surface
density and investigate the impact of diffuse emission on this
calibration using a structural decomposition. Separating the thermal
and non- thermal emission components, the correlation between
different phases of the ISM, and the impact of massive star formation
are being investigated. Radio sources with sizes ≲ 200 pc constitute
about 36 per cent (46 per cent) of the total RC emission at 1.5 GHz
(6.3 GHz) in the inner 18 * 18 arcmin2 (or 4 kpc * 4 kpc) disc of M
33. The non-thermal spectral index becomes flatter with increasing
star formation rate surface density, indicating the escape of cosmic
ray electrons from their birth places. The magnetic field strength
also increases with star formation rate following a bi-modal relation,
indicating that the small-scale turbulent dynamo acts more efficiently
at higher luminosities and star formation rates. Although the
correlations are tighter in star-forming regions, the non-thermal
emission is also correlated with the more quiescent molecular gas in
the ISM. An almost linear molecular star formation law exists in M 33
when excluding diffuse structures. Massive star formation amplifies
the magnetic field and increases the number of high-energy cosmic ray
electrons, which can help the onset of winds and outflows.
Description:
We performed interferometer observations with VLA by using in
D/C-configurations the C (5.5-7.5GHz) and L (1-2GHz) bands centered on
6.3GHz and 1.5GHz respectively. Here we present the observational data
as positional and flux data with their errors for the 516 and 488
radio sources detected in these two bands (i.e observations and data
reduction/extraction are presented in section 2, section 3 for TH/NTH
separation and section 4 for RC results). The table5.dat regroups M33
RCs in L-band and table6.dat in C-band. Also, we provide reduced and
calibrated fits images in these two VLA bands.
Objects:
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RA (2000) DE Designation(s)
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01 33 50.89 +30 39 36.6 M 33 = NAME Triangulum Galaxy
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table5.dat 113 516 Radio sources detected in M33 at 1.5GHz VLA
L-band in D/C-configurations
table6.dat 113 488 Radio sources detected in inner 18*18 arcmin2
M33 at 6.3GHz VLA C-band in D/C-configurations
list.dat 99 2 List of fits images
fits/* . 2 Individual fits images of M33
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See also:
J/MNRAS/506/3079 : Halpha and other SFR indicators (Kouroumpatzakis+, 2021)
J/MNRAS/476/158 : Radio haloes in nearby galaxies (Heesen+, 2018)
J/MNRAS/449/4048 : The Hα rotation curve of M33 (Kam+, 2015)
J/A+A/522/A3 : M33 CO(2-1) and HI integrated intensity maps (Gratier+,2010)
J/A+A/578/A8 : Multi-resolution images of M33 (Boquien+, 2015)
J/A+A/472/785 : Radio continuum survey of M33 (Tabatabaei+, 2007)
J/A+A/552/A19 : Radio-farIR correlation in NGC 6946 (Tabatabaei+, 2013)
J/ApJ/856/67 : VLA 3GHz radio source catalog in the Lockman Hole
(Cotton+, 2018)
J/ApJ/836/185 : SEDs of the radio continuum from KINGFISHER
(Tabatabaei+, 2017)
J/ApJS/260/41 : Dust extinction law in nearby galaxies. II. M33
(Wang+, 2022)
J/ApJS/120/247 : Supernova remnants in M33 (Gordon+, 1999)
J/ApJS/241/37 : 1.4 and 5GHz deep JVLA radio survey of M33 (White+, 2019)
J/ApJS/178/247 : Hα and [NII] survey in local 11 Mpc (Kennicutt+, 2008)
J/ApJS/187/495 : SNRs in M33 from optical and X-ray (Long+, 2010)
J/AJ/142/111 : Total infrared brightness and SFR in M33 (Boquien+, 2011)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
Byte-by-byte Description of file: table5.dat table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- ID Identifier raw number (ID)
5- 14 F10.3 uJy/beam P Peak flux dentity (P) (1)
16- 25 F10.3 uJy S Integrated flux density (S) (1)
27- 28 I2 h RAh Right ascension (J2000)
30- 31 I2 min RAm Right ascension (J2000)
33- 38 F6.3 s RAs Right ascension (J2000)
40 A1 --- DE- Declination sign (J2000)
41- 42 I2 deg DEd Declination (J2000)
44- 45 I2 arcmin DEm Declination (J2000)
47- 52 F6.3 arcsec DEs Declination (J2000)
54- 59 F6.3 arcsec MajAxis Deconvolution of the best-fitting major
axis (Maj)
61- 66 F6.3 arcsec MinAxis Deconvolution of the best-fitting minor
axis (Min)
68- 70 I3 deg PA Deconvolution of the best-fitting position
angle (PA)
72- 77 F6.3 uJy/beam e_P Mean error of P (eP) (1)
79- 84 F6.2 uJy e_S Mean error of S (eS) (1)
86- 90 F5.3 s e_RAs Mean error of the right ascension (eRA)
92- 96 F5.3 arcsec e_DEs Mean error of the declination (eDE)
98-103 F6.3 arcsec e_MajAxis Mean error of MajAxis (eMaj)
105-109 F5.3 arcsec e_MinAxis Mean error of MinAxis (eMin)
111-113 I3 deg e_PA Mean error of PA (ePA)
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Note (1): Peak and integrated flux densities at 1.5GHz for table5.dat
and 6.3GHz for table6.dat.
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Nx Number of pixels along X-axis
6- 9 I4 --- Ny Number of pixels along Y-axis
11- 14 I4 Kibyte size Size of FITS file
16- 28 A13 --- FileName Name of FITS file, in subdirectory fits
30- 99 A70 --- Title Title of the FITS file
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History:
From electronic version of the journal
(End) Luc Trabelsi [CDS] 21-Oct-2025