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J/PAZh/21/13    New list of OB associations              (Melnik+, 1995)

New list of OB associations of our Galaxy. Melnik A.M., Efremov Yu.N. <Pis'ma Astron. Zh. 21, 13 (1995)> =1995PAZh...21...13M
ADC_Keywords: Milky Way ; Associations, stellar ; Stars, OB ; Stars, early-type Abstract: A new partition into associations of OB stars within 3kpc of the Sun is derived using Battinelli's modification of the cluster analysis method. We have found 58 associations, of which only 10% may be considered as a random clusters of field stars. Description: We identified 88 associations with at least 5 members which average characteristics are shown in Table 1 of the paper by Mel'nik and Efremov (1995PAZh...21...13M). The new table (list.dat) exhibits the list of 1392 stars -- members of 88 associations of the new partition. For each star we give its name, spectral type, V magnitude, galactic coordinates l and b, distance from the Sun rBH. All these values are taken from the catalog by Blaha and Humphreys (1989AJ..98...1598B) which includes two parts: the catalog of young stars -- members of associations or clusters and the catalog of field stars. The last two columns exhibit the name of association to which the star is included in the partition by Blaha and Humphreys (Assc_BH) and in the partition by Mel'nik and Efremov (Assc_ME). The letter F in the last but one column means that it is a field star in the catalog by Blaha and Humphreys (1989AJ..98...1598B). There are some evidences that the distance scale by Blaha and Humphreys (r_BH) should be shorten by 10-20% (Dambis et al. 2001AstL..27...58D; Mel'nik and Dambis 2009, Cat. J/MNRAS/400/518). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table.dat 75 88 Table of OB-associations list.dat 67 1392 List of stars -- members of OB associations of the new partition
Byte-by-byte Description of file: table.dat
Bytes Format Units Label Explanations
1- 9 A9 --- AssME Association name 11- 16 F6.2 deg GLON Galactic longitude 18- 23 F6.2 deg GLAT Galactic latitude 26- 29 F4.2 kpc D Distance 32- 36 F5.1 km/s RV ? Average radial velocity of the association relative to the Sun 40- 43 F4.1 km/s e_RV ? Dispersion of RV 46- 47 I2 --- NRV Number of stars with measured RV 50- 52 I3 --- Ntot Total number of stars in the association 57- 61 F5.1 pc Dl Size of association along longitude 65- 68 F4.1 pc Db Size of association along latitude 71 I1 --- p [0/1] p=1 for the association with 90% reliability p=0 for reliability below 90% 74- 75 I2 --- Nsg Number of K and M supergiants
Byte-by-byte Description of file: list.dat
Bytes Format Units Label Explanations
1- 14 A14 --- Name Designation of the star 16- 19 A4 --- SpType MK spectral type 21- 25 F5.2 mag Vmag Magnitude in V band 27- 32 F6.2 deg GLON Galactic longitude 34- 39 F6.2 deg GLAT Galactic latitude 42- 45 F4.2 kpc rBH Distance from the Sun derived by BH 48- 55 A8 --- AssBH Association of Blaha and Humphreys, 1989AJ..98...1598B 59- 67 A9 --- AssME Association of Mel'nik and Efremov, as in table.dat file
History: * 25-Sep-1997: Original * 06-Oct-2011: list.dat added, from Anna Mel'nik, anna(at)
(End) Veta Avedisova [INASAN] 10-Jul-1997
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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