J/A+A/357/871 RR Lyrae stars in the Sgr dwarf galaxy (Cseresnjes+, 2000)
Structure of the Sagittarius dwarf galaxy at low Galactic latitudes.
Cseresnjes P., Alard C., Guibert J.
<Astron. Astrophys., 357, 871-880 (2000)>
=2000A&A...357..871C 2000A&A...357..871C
ADC_Keywords: Stars, variable ; Magnitudes
Keywords: stars: variables: RR Lyr - galaxies: individual: Sagittarius -
galaxies: dwarf - galaxies: Local Group
Abstract:
We carried out a search for RR Lyrae stars towards the Sagittarius
dwarf galaxy based on two series of photographic Schmidt plates. This
search yielded 4013 RR Lyrae stars (3947 mono-periodic, and 66
multi-periodic) spread over ∼50 square degrees between Galactic
latitudes b=-4° and b=-15°. The analysis of this catalog of RR
Lyraes allowed us to map the structure of the Sagittarius dwarf galaxy
behind the high density of Galactic foreground stars (this paper,
Paper I), and to study the properties of the old stellar population in
the Sgr dwarf (Paper II, Cseresnjes, 2001, Cat. J/A+A/375/909).
Description:
The catalog of single-period RR Lyraes is composed of two tables, one
for each field:
- filed1.dat for variables detected in field 1 (SAG) centered on
(l,b)=(6.6°, -10.8°). The photometry of these RR Lyraes is
based on a combination of a Kodak Tech-Pan 4415 film with a BG12
filter.
- field2.dat for variables detected in field 2 (DUO) centered on
(l,b)=(3.1°, -7.1°). The photometry is based on the Bj
system.
It is important to note that the photometric systems are different
between the two fields (see paper I & II for details). The magnitude
and amplitude are therefore not directly comparable from one field to
another.
The RR Lyrae stars of this catalog are almost evenly distributed
between the Sagittarius dwarf and the Galaxy. They are easily
separated through an histogram of the magnitudes (see Paper I).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
field1.dat 52 2330 Single-period RR Lyraes in field 1 (SAG)
field2.dat 52 1617 Single-period RR Lyraes in field 2 (DUO)
lc/* 24 73 Light curves
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See also:
J/A+A/375/909 : RR Lyrae stars in the Sgr dwarf (Paper II) (Cseresnjes 2001)
Byte-by-byte Description of file: field1.dat field2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Variable identifier
11- 19 F9.6 h RAhour Right ascension (J2000)
21- 29 F9.5 deg DEdeg Declination (J2000)
31- 37 F7.5 d Per Period of the variable
39- 42 F4.2 mag Amp Amplitude of the light curve
44- 47 F4.1 mag Bmag Photographic B magnitude
49- 52 A4 --- VarType Type of the variable (either RRab or RRc)
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Byte-by-byte Description of file: lc/*
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Bytes Format Units Label Explanations
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1- 13 F13.5 d JD Observation date
15- 19 F5.2 mag Bmag Observed B magnitude
21- 24 F4.2 mag e_Bmag Mean error on Bmag
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Acknowledgements: Patrick Cseresnjes
History:
* 25-May-2004: Original version
* 01-Mar-2012: The RA column contains decimal hours
(was indicated in the original description as decimal degrees)
[communicated by N. Samus, Moscow]
References:
Cseresnjes, Paper II 2001A&A...375..909C 2001A&A...375..909C, Cat. J/A+A/375/909
(End) Patricia Bauer [CDS] 25-May-2004