J/A+A/427/613 V,i,TiOr,CN photometry of And-II AGB stars (Kerschbaum+, 2004)
A census of AGB stars in Local Group galaxies. III. The dwarf spheroidal And II.
Kerschbaum F., Nowotny W., Olofsson H., Schwarz H.E.
<Astron. Astrophys., 427, 613-619 (2004)>
=2004A&A...427..613K 2004A&A...427..613K (
ADC_Keywords: Stars, giant ; Photometry ; Stars, late-type
Keywords: stars: AGB and post-AGB - stars: carbon - galaxies: local Group -
galaxies: individual: And II - techniques: photometric - surveys
Abstract:
Our photometric survey of Local Group galaxies, using a four filter
technique based on the method of Wing (1971, Proc. Conf. Late-Type
Stars, ed. G.W. Lockwood and H.M. Dyck, KPNO Contribution 554, 145)
allows the identification and subsequent characterization of their
late-type stellar content. Two narrow band filters centred on
molecular bands of TiO and CN allow us to distinguish between AGB
stars of different chemistries [M-type (O-rich) and C-type (C-rich)].
The faint dwarf spheroidal galaxy And II, a member of the M 31
subgroup, was surveyed. From photometry in V and i as well as in the
narrow band filters TiO and CN we were able to identify 7 new AGB
carbon stars, to derive their mean absolute <Mi> and bolometric
magnitude Mbol, their luminosity function, and their spatial
distribution. We are unable to establish the true C/M ratio because
the few M stars of And II are overwhelmed by foreground Galactic M st
Description:
Our observations were obtained with the 2.56 m Nordic Optical
Telescopeat La Palma (Spain) during the nights of September 1 and 2,
2000. We observed the field in the four filters described in Table 2.
Objects:
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RA (2000) DE Designation(s)
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01 16 29.8 +33 25 54 And II
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 61 2307 And II results
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See also:
J/AJ/127/318 : BV photometry of Andromeda II variables (Pritzl+, 2004)
Table 2: Observing log.
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Filter NOT# lambdac δλ System Exposure Time
(Å) (Å) (s)
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V 75 5300 800 Bessell 3x1200
i 12 7970 1570 Gunn 2x600
TiO 7780 110 Wing 6x1200
CN 8113 85 Wing 6x1200
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Seq Sequential number
7- 10 I4 pix Xpos X position
12- 15 I4 pix Ypos Y position
17- 18 I2 h RAh Right ascension (J2000.0)
20- 21 I2 min RAm Right ascension (J2000.0)
23- 28 F6.3 s RAs Right ascension (J2000.0)
30 A1 --- DE- Declination sign (J2000.0)
31- 32 I2 deg DEd Declination (J2000.0)
34- 35 I2 arcmin DEm Declination (J2000.0)
37- 41 F5.2 arcsec DEs Declination (J2000.0)
43 A1 --- Flag [coru] Special flag which denotes in which
region of Fig. 3 the star falls (1)
45- 49 F5.2 mag imag Gunn i magnitude
51- 55 F5.2 mag V-i V-i colour index (see "Table 2" section above)
57- 61 F5.2 mag TiO-CN ? TiO-CN index (see "Table 2" section above)
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Note (1): Region of Fig. 3 in which the star falls:
c for carbon stars,
o for oxygen-rich stars,
r for the rest,
u for unclassified
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Acknowledgements: Franz Kerschbaum, kerschbaum(at)astro.univie.ac.at
(End) Patricia Vannier [CDS] 19-Nov-2004