J/A+A/436/91 C star population in outer disk of M31 (Demers+, 2005)
The C star outer disk population of M31 seen with the SLOAN filters.
Demers S., Battinelli P.
<Astron. Astrophys. 436, 91 (2005)>
=2005A&A...436...91D 2005A&A...436...91D
ADC_Keywords: Stars, carbon ; Photometry, CCD ; Photometry, SDSS
Keywords: galaxies: individual: M31 - stars: carbon
Abstract:
We employ the CFHT Megacam camera to survey ∼1°2 of the southern
outer disc of M31, a region which includes the area where Battinelli
et al. (2003, Cat. J/AJ/125/1298) have identified nearly one
thousand C stars. In the outer M31 region not previously surveyed, we
identify 361 new C star candidates, having similar photometric
properties to the known ones, and confirm the slight decrease in the
luminosity of C stars with galactocentric distances. We show that the
Sloan g', r', i' filters are a viable approach, comparable to
(CN-TiO), to identify C stars. We find that the (g'-r') colours of
cool C stars can be so red that prohibitively long g' exposures are
needed to acquire faint extragalactic C stars. This makes the Sloan
filters a less promising approach to extend a C star survey to several
Mpc. Our uniform large field survey detects the edge of M31 disk at
∼35kpc. The intermediate-age population, represented by C stars,
extends further to ∼40kpc.
Description:
The observations presented in this paper consist of one Megacam filed,
centered on RA=00:37:02.3, DE=+39:40:50 (J2000.0), obtained in Service
Queue Observing mode in August 2003.
TheMegacam camera is installed at the prime focus of the 3.66m
Canada-France-Hawaii Telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 76 463 Positions and photometry of 463 C stars
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See also:
J/AJ/125/1298 : C star population in outer disk of M31 (Battinelli+, 2003)
J/AJ/125/3037 : RI photometry of NGC 205 carbon stars (Demers+, 2003)
J/A+A/424/125 : Carbon stars in IC10 (Demers+, 2004)
J/A+AS/97/603 : C stars in SMC (Rebeirot+ 1993)
J/A+A/416/111 : C stars in Wolf-Lundmark-Melotte galaxy (Battinelli+, 2004)
J/A+A/417/479 : RI photometry of NGC 185 carbon stars (Battinelli+, 2004)
J/A+A/410/795 : Photometry of NGC 3109 carbon stars (Demers+, 2003)
J/AJ/125/3037 : RI photometry of NGC 205 carbon stars (Demers+, 2003)
J/AJ/120/1801 : C stars in Pegasus, DDO 210 and Tucana (Battinelli+, 2000)
J/AJ/119/2780 : C stars in IC 1613 (Albert+, 2000)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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3- 5 I3 --- Seq Running number
8- 16 F9.7 deg RAdeg Right ascension (J2000.0)
19- 28 F10.7 deg DEdeg Declination (J2000.0)
31- 36 F6.3 --- i'mag SDSS i' magnitude
40- 44 F5.3 --- e_i'mag Error on i'mag
48- 52 F5.3 --- (r'-i') SDSS (r'-i') colour index
56- 60 F5.3 --- e_(r'-i') Error on (r'-i')
64- 68 F5.3 --- (g'-r') SDSS (g'-r') colour index
72- 76 F5.3 ---- e_(g'-r') Error on g'-r'
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Acknowledgements: Serge Demers, demers(at)astro.umontreal.ca
Paolo Battinelli, battinel(at)oarhp1.rm.astro.it
(End) Patricia Vannier [CDS] 08-Mar-2005