J/A+A/682/A180       IRDC G14.225-0.506 stellar population (Diaz-Marquez+, 2024)

Radio survey of the stellar population in the infrared dark cloud G14.225-0.506. Diaz-Marquez E., Grau R., Busquet G., Girart J.M., Sanchez-Monge A., Palau A., Povich M.S., Anez-Lopez N., Liu H.B., Zhang Q., Estalella R. <Astron. Astrophys. 682, A180 (2024)> =2024A&A...682A.180D 2024A&A...682A.180D (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Infrared sources ; Radio sources Keywords: stars: formation - ISM: jets and outflows - radio continuum: ISM - ISM: individual objects: G14.225-0.506 Abstract: The IRDC G14.225-0.506 is associated with a network of filaments, which result in two different dense hubs, as well as with several signposts of star formation activity. The aim of this work is to study the cm continuum emission to characterize the stellar population in G14.2. We performed deep (∼1.5-3uJy) radio continuum observations at 6 and 3.6cm using the VLA in the A configuration (∼0.3''). We have also made use of observations taken during different days to study the presence of variability at short timescales. We detected a total of 66 sources, 32 in the northern region G14.2-N and 34 in the southern region G14.2-S. Ten of the sources are found to be variable. Based on their spectral index, the emission in G14.2-N is mainly dominated by non-thermal sources while G14.2-S contains more thermal emitters. Approximately 75% of the sources present a counterpart at other wavelengths. In the inner 0.4pc region around the center of each hub, the number of IR sources in G14.2-N is larger than in G14.2-S by a factor of 4. We also studied the relation between the radio luminosity and the bolometric luminosity, finding that the thermal emission of the studied sources is compatible with thermal radio jets. For our sources with X-ray counterparts, the non-thermal emitters follow a Guedel-Benz relation with k=0.03. We found similar levels of fragmentation between G14.2-N and G14.2-S, suggesting that both regions are most likely twin hubs. The non-thermal emission found in the less evolved objects suggests that G14.2-N may be composed of more massive YSOs as well as being in a more advanced evolutionary stage, consistent with the filament-halo gradient in age and mass from previous works. Our results confirm a wider evolutionary sequence starting in G14.2-S as the youngest part, followed by G14.2-N, and ending with the most evolved region M17. Description: Full tables C.1 and C.2 of Appendix C showing the positions and parameters of the radio sources detected at C- and X-band in the IRDC G14.225-0.506. Objects: --------------------------------------------------------------- RA (2000) DE Designation(s) --------------------------------------------------------------- 18 19 00.00 -16 40 00.0 G14.225-0.506 = GAL 014.225-00.506 --------------------------------------------------------------- File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table6.dat 78 32 Spectral indices of the radio sources located in G14.2-N table7.dat 78 35 Spectral indices of the radio sources located in G14.2-S tablec1.dat 148 53 Parameters of the radio sources detected at C-band tablec2.dat 148 36 Parameters of the radio sources detected at X-band list.dat 124 4 List of fits images fits/* . 4 Individual fits images -------------------------------------------------------------------------------- Byte-by-byte Description of file: table6.dat table7.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 6 A6 --- Source Name of the detected source (VLA-NN) 8- 21 F14.9 uJy SC Integrated flux detected at C-band 23- 35 F13.9 uJy e_SC ? Error in the integrated flux detected at C-band 37- 49 F13.8 uJy SX Integrated flux detected at X-band 51- 63 F13.9 uJy e_SX ? Error in the integrated flux detected at X-band 65- 69 F5.2 --- SpId Spectral index 71- 74 F4.2 --- e_SpId ? Error in the spectral index 76 A1 --- upp [Y/N] Upper limit? 78 A1 --- low [Y/N] Lower limit? -------------------------------------------------------------------------------- Byte-by-byte Description of file: tablec1.dat tablec2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 6 A6 --- Source Name of the detected source (VLA-NN) 8 A1 --- HUB [N/S] Region where the source is located 10- 11 I2 h RAh Right ascension (J2000) 13- 14 I2 min RAm Right ascension (J2000) 16- 23 F8.5 s RAs Right ascension (J2000) 25- 31 F7.5 s e_RAs Error in the right ascension 33 A1 --- DE- Declination sign (J2000) 34- 35 I2 deg DEd Declination (J2000) 37- 38 I2 arcmin DEm Declination (J2000) 40- 47 F8.5 arcsec DEs Declination (J2000) 49- 55 F7.5 arcsec e_DEs Error in the declination 57- 70 F14.9 uJy Scorr Integrated flux corrected for the primary beam attenuation 72- 84 F13.9 uJy e_Scorr Error in the integrated flux 86-100 F15.10 uJy/beam Ipeakcorr Peak intensity corrected for the primary beam attenuation 102-121 F20.16 uJy/beam e_Ipeakcorr Error in the peak intensity 123-135 F13.8 mas Size ?=0 Size of the source 137-142 F6.2 deg PA ? Position angle 144-148 F5.2 deg e_PA ? Error in the position angle -------------------------------------------------------------------------------- Byte-by-byte Description of file: list.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 9 F9.5 deg RAdeg Right Ascension of center (J2000) 10- 18 F9.5 deg DEdeg Declination of center (J2000) 20- 23 I4 --- Nx Number of pixels along X-axis 25- 28 I4 --- Ny Number of pixels along Y-axis 30- 56 A27 "datime" Obs.date Observation date 57- 67 E11.6 Hz Freq Observed frequency 69- 74 I6 Kibyte size Size of FITS file 76- 95 A20 --- FileName Name of FITS file, in subdirectory fits 97-124 A28 --- Title Title of the FITS file -------------------------------------------------------------------------------- Acknowledgements: Elena Diaz-Marquez, ediazm(at)fqa.ub.edu
(End) Patricia Vannier [CDS] 04-Dec-2023
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