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J/A+A/281/161      Radio emission from stars at 250GHz  (Altenhoff+, 1994)

Radio emission from stars: a survey at 250 GHz Altenhoff W.J., Thum C., Wendker H.J. <Astron. Astrophys. 281, 161 (1994)> =1994A&A...281..161A
ADC_Keywords: Stars, radio; Stars, OB; Stars, Wolf-Rayet; Stars, early-type; Stars, pre-main sequence; Stars, giant; Stars, supergiant; Stars, variable Keywords: radio stars - stellar wind - Wolf-Rayet stars - giants and supergiants - pre-main sequence stars - variable stars Abstract: We have used the IRAM 30 m-telescope together with the Max Planck Institute for Radio Astronomy (MPIfR) bolometer to survey nearly 270 stars of different types for 250GHz continuum emission. We compare these data with their low frequency (cm-range) properties. Early type stars show very often a deviation from the uniformly expanding wind model which we tentatively attribute to temperature and/or density fluctuations in their deeper atmospheric layers. For WR stars this deviation seems to depend on the effective temperature. Pre-main sequence stars usually seem to be surrounded by a shell of warm dust making a substantial contribution to the 250 GHz flux density value. We have found especially for nearby giants and supergiants that a layer at the transition from photosphere to chromosphere emits ample 250 GHz radiation. We show that the present data can still be explained by a simple uniformly illuminated disk model with the known stellar radius. Optically variable stars are not very strong emitters at 250 GHz. We preferentially detected the more exotic ones, a few Beta Lyr-type and symbiotic stars. Comments on many individual objects are given in the appropriate sections. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 98 21 O and B stars table5.dat 98 24 WR stars table6.dat 98 10 Early-type stars with shelles table7.dat 98 42 Pre-main sequence stars table8.dat 98 95 Stellar disks (giants+supergiants) table9.dat 53 28 Stars with determined radii table10.dat 98 76 Variable stars
Byte-by-byte Description of file: table[4-8].dat table10.dat
Bytes Format Units Label Explanations
1- 15 A15 --- Name Star name 17- 27 A11 --- SpType MK spectral type (table8 only) 29 A1 --- l_S(250) Limit flag on S(250) 30- 35 F6.1 mJy S(250) ? Flux in continuum at 250GHz 37- 41 F5.1 mJy e_S(250) ? rms uncertainty on S(250) 43- 50 A8 --- Sess List of session numbers 53 A1 --- l_alf [>≲] Limit flag on spectral index 54- 58 F5.2 --- alf ? Spectral index (S(ν)∝ν-{alf}) 60- 63 F4.2 --- e_alf ? rms uncertainty on spectral index 64 A1 --- u_alf [?] Uncertainty flag on alf 66- 98 A33 --- Rem Remarks
Byte-by-byte Description of file: table9.dat
Bytes Format Units Label Explanations
1- 10 A10 --- Name Star name 12- 22 A11 --- SpType MK spectral type 24- 28 F5.2 mas R(UD) Stellar radius 33- 37 A5 --- Refs References (1) 40 A1 --- l_S(250) Limit flag on S(250) 41- 45 F5.1 mJy S(250) Flux in continuum at 250GHz 48 A1 --- l_T(disk) Limit flag on disk temperature 49- 53 I5 K T(disk) Disk temperature
Note (1): references are numbered as follows: 1 = Mozurkewich et al. 1991AJ....101.2207M 2 = di Benedetto & Rabbia 1987A&A...188..114D 3 = Hutter et al. 1989ApJ...340.1103H 4 = this article (see text) 5 = Fracassini et al. 1981A&AS...45..145F 6 = Hanbury Brown et al. 1974MNRAS.167..121H 7 = di Benedetto & Foy 1986A&A...166..204D 8 = Christou & Worden 1980AJ.....85..302C 9 = di Benedetto & Ferluga 1990A&A...236..449D
History: * 14-Oct-1993: Original version from author * 09-Apr-2008: homogenized the descriptions of the various tables
(End) Patricia Vannier, Francois Ochsenbein [CDS] 09-Apr-2008
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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