J/A+A/449/143 Photometry of M31 globular cluster candidates (Ma+, 2006)
Age estimations of M31 globular clusters from their
spectral energy distributions.
Ma J., Zhou X., Burstein D., Yang Y., Fan Z., Chen J., Jiang Z.,
Wu Z., Wu J., Zhang T.
<Astron. Astrophys. 449, 143 (2006)>
=2006A&A...449..143M 2006A&A...449..143M
ADC_Keywords: Clusters, globular ; Energy distributions
Keywords: galaxies: individual: M31 - galaxies: star cluster -
galaxies: evolution
Abstract:
This paper presents accurate spectral energy distributions (SEDs) of
16 M31 globular clusters (GCs) confirmed by spectroscopy and/or high
spatial-resolution imaging, as well as 30 M31 globular cluster
candidates detected by Mochejska et al., Cat. J/AcA/48/455
(1998). Most of these candidates have mV>18, deeper than previous
searches, and these candidates have not yet been confirmed to be
globular clusters. The SEDs of these clusters and candidates are
obtained as part of the BATC Multicolor Survey of the Sky, in which
the spectrophotometrically-calibrated CCD images of M31 in 13
intermediate-band filters from 4000 to 10000Å were observed. These
filters are specifically designed to exclude most of the bright and
variable night-sky emission lines including the OH forest. In
comparison to the SEDs of true GCs, we find that some of the candidate
objects are not GCs in M31. SED fits show that theoretical simple
stellar population (SSP) models can fit the true GCs very well. We
estimate the ages of these GCs by comparing with SSP models.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sources.dat 32 45 Globular cluster positions
table1.dat 29 13 Parameters of the BATC filters and statistics
of observations for M 31
table2.dat 23 585 Magnitudes in BATC filters
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See also:
II/262 : BATC Data Release One - BATC DR1 (Zhou+ 1995-2005)
J/AJ/127/2579 : Optical ident. of BATC Sky Survey X-ray sources (Zhang+, 2004)
J/A+A/397/361 : 15-color BATC photometry of Landolt SA95 field (Zhou+, 2003)
J/AJ/122/1718 : Multicolor photometry in Abell 2634 (Yuan+, 2001)
J/AJ/112/628 : BATC Color Survey of M67 (Fan+ 1996)
J/AcA/48/455 : Globular Clusters in M31 and M33 (Mochejska+, 1998)
Byte-by-byte Description of file: sources.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Name Name of the globular cluster candidate (MNNN),
[MKK98] M 31 NNN in Simbad
6- 7 I2 h RAh Right ascension (J2000) (1)
9- 10 I2 min RAm Right ascension (J2000) (1)
12- 16 F5.2 s RAs Right ascension (J2000) (1)
18 A1 --- DE- Declination sign (J2000) (1)
19- 20 I2 deg DEd Declination (J2000) (1)
22- 23 I2 arcmin DEm Declination (J2000) (1)
25- 28 F4.1 arcsec DEs Declination (J2000) (1)
30- 32 I3 --- [MKK98] Mochejska et al. (J/AcA/48/455)
sequential number
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Note (1): Positions from Mochejska et al. (J/AcA/48/455).
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- No Filter number
4- 9 A6 --- Filter Filter name
11- 14 I4 0.1nm cw Central wavelength for each BATC filter
16- 20 A5 --- Exp Exposition time (hh:mm)
22- 23 I2 --- Nimg Image numbers for each BATC filter
25- 29 F5.3 mag rms Calibration error for each filter as
obtained from the standard stars
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Name Name of globular cluster candidates (MNNN),
[MKK98] M 31 NNN in Simbad
6- 11 A6 --- Filter Name of the BATC filter
13- 17 F5.2 mag mag ?=- Magnitude in the Filter
19- 23 F5.3 mag e_mag ?=- rms uncertainty on magnitude
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Acknowledgements:
Jun Ma, majun(at)vega.bac.pku.edu.cn
(End) Patricia Vannier [CDS] 06-Dec-2005