Access to Astronomical Catalogues

← Click to display the menu
J/A+A/549/A27       M31  CO(2-1) spectra                     (Melchior+, 2013)

A cold-gas reservoir to fuel the M31 nuclear black hole and stellar cluster. Melchior A.-L., Combes F. <Astron. Astrophys. 549, A27 (2013)> =2013A&A...549A..27M
ADC_Keywords: Planetary nebulae ; Carbon monoxide ; Radial velocities ; Galaxies, spectra Keywords: Galaxies: individual - galaxies: nuclei - galaxies: kinematics and dynamics - Galaxies: bulges - galaxies: ISM - ISM: planetary nebulae: general Abstract: With IRAM-30m/HERA, we have detected CO(2-1) gas complexes within 30arcsec (100pc) from the center of M31 that amount to a minimum total mass of 4.2x104M (one third of the positions are detected). Averaging the whole HERA field, we show that there is no additional undetected diffuse component. Moreover, the gas detection is associated with gas lying on the far side of the M31 center as no extinction is observed in the optical, but some emission is present on infrared Spitzer maps. The kinematics is complex. (1) The velocity pattern is mainly redshifted: the dynamical center of the gas differs from the black hole position and the maximum of optical emission, and only the redshifted side is seen in our data. (2) Several velocity components are detected in some lines of sight. Our interpretation is supported by the reanalysis of the effect of dust on a complete planetary nebula sample. Two dust components are detected with respective position angles of 37deg and -66deg. This is compatible with a scenario where the superposition of the (PA=37deg) disk is dominated by the 10kpc ring and the inner 0.7kpc ring detected in infrared data, whose position angle (-66deg) we measured for the first time. The large-scale disk, which dominates the HI data, is steeply inclined (i=77deg), warped and superposed on the line of sight on the less inclined inner ring. The detected CO emission might come from both components. Description: 36 reduced spectra obtained at IRAM-30m are provided in ascii format. They are presented in Figure 1 of the article. Objects: ----------------------------------------- RA (2000) DE Designation(s) ----------------------------------------- 00 42 44.33 +41 16 07.5 M31 = UGC 454 ----------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file m31-1aof.dat 24 36 Offset of each spectrum sp/* 19 36 Individual spectra
Byte-by-byte Description of file: m31-1aof.dat
Bytes Format Units Label Explanations
2- 3 I2 --- Nsp Spectrum number 5- 7 I3 arcsec offX X offset (1) 9- 11 I3 arcsec offY Y offset (1) 13- 24 A12 --- FileName Name of spectrum file in subdirectory sp
Note (1): the offsets are computed with respect to the center of M31 00:42:44.37+41:16:08.34 (J2000)
Byte-by-byte Description of file: sp/*
Bytes Format Units Label Explanations
1- 7 F7.2 km/s Vlsr LSR Velocity 8- 19 F12.8 K Tmb Main beam temperature
Acknowledgements: Anne-Laure Melchior, A.L.Melchior(at)obspm.fr
(End) Anne-Laure Melchior [LERMA, France], Patricia Vannier [CDS] 15-Nov-2012
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

catalogue service

© UDS/CNRS

Contact