J/MNRAS/428/2216 JHKs photometry of AGB stars in NGC 6822 (Whitelock+, 2013)
The Local Group galaxy NGC 6822 and its asymptotic giant branch stars.
Whitelock P.A., Menzies J.W., Feast M.W., Nsengiyumva F., Matsunaga N.
<Mon. Not. R. Astron. Soc., 428, 2216-2231 (2013)>
=2013MNRAS.428.2216W 2013MNRAS.428.2216W
ADC_Keywords: Galaxies, photometry ; Stars, giant ; Photometry, infrared
Keywords: stars: carbon - galaxies: distances and redshifts -
galaxies: individual: NGC 6822 - Local Group - infrared: stars -
stars: AGB and post-AGB
Abstract:
JHKs photometry is presented from a 3.5yr survey of the central
regions of the irregular galaxy NGC 6822. The morphology of the
colour-magnitude and colour-colour diagrams is discussed with
particular reference to M-, S- and C-type asymptotic giant branch
(AGB) stars and to M supergiants. Mean JHKs magnitudes and periods are
given for 11 O-rich and 50 presumed C-rich Miras. Data are also listed
for 27 large-amplitude AGB stars without periods and for 69
small-amplitude AGB variables. The slope of the bolometric
period-luminosity relation for the C-rich Miras is in good agreement
with that in the Large Magellanic Cloud. Distance moduli derived from
the C- and O-rich Miras are in agreement with other estimates. The
period distribution of C-rich Miras in NGC 6822 is similar to that in
the Magellanic Clouds, but differs from that in the dwarf spheroidals
in the Local Group. In the latter there is a significant proportion of
large-amplitude, short-period variables indicating a population
producing old carbon-rich AGB stars.
Description:
JHKs photometry for stars in three overlapping fields centred on
NGC 6822 obtained at SAAO, Sutherland with the IRSF infrared telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 95 6257 Data for stars with standard errors less
than 0.1mag
table3.dat 72 7 Stars with known S spectral type
table4a.dat 69 11 Periodic large-amplitude O-rich variables (Miras)
table4b.dat 69 50 Periodic large-amplitude C-rich variables (Miras)
table5.dat 74 27 Large-amplitude variables
table6.dat 72 69 Small-amplitude variables
table7.dat 30 16 Variables in common with the Battinelli &
Demers (2011A&A...525A..69B 2011A&A...525A..69B)
table10.dat 20 60 Bolometric magnitudes of the assumed C-rich Miras
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See also:
J/ApJ/501/153 : VRB photometry of red supergiants (Massey 1998)
J/A+A/429/837 : IJKs photometry of late-type stars in NGC 6822 (Cioni+, 2005)
J/AJ/132/378 : HST and UV photometry of NGC 6822 (Bianchi+, 2006)
J/AJ/132/1372 : Chandra observation of NGC 6822 (Tennant+, 2006)
J/A+A/454/717 : NGC 6822 near-IR photometry of C and AGB stars (Kang+, 2006)
J/A+A/537/A108 : NGC 6822 AGB spectroscopic catalogue (Kacharov+, 2012)
J/A+A/540/A135 : AGB population of NGC 6822 (Sibbons+, 2012)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right ascension (J2000)
11- 19 F9.5 deg DEdeg Declination (J2000)
21- 25 I5 --- Seq [10001/40643] Catalogue Number (this paper)
28- 33 F6.3 mag Jmag [12.5/20.0] Mean J magnitude
35- 39 F5.3 mag e_Jmag J standard deviation
41- 46 F6.3 mag Hmag [12.0/18.5] Mean H magnitude
48- 52 F5.3 mag e_Hmag H standard deviation
54- 59 F6.3 mag Ksmag [11.9/18.3] Mean Ks magnitude
61- 65 F5.3 mag e_Ksmag Ks standard deviation
67- 72 F6.3 mag J-H J-H colour index
74- 79 F6.3 mag H-Ks H-Ks colour index
81- 86 F6.3 mag J-Ks J-Ks colour index
88- 89 I2 --- o_Jmag [2/36] Number of J observations averaged
91- 92 I2 --- o_Hmag [2/36] Number of H observations averaged
94- 95 I2 --- o_Ksmag [2/36] Number of Ks observations averaged
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Byte-by-byte Description of file: table3.dat table5.dat table6.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right ascension (J2000)
11- 19 F9.5 deg DEdeg Declination (J2000)
21- 25 I5 --- Seq [10001/40643] Catalogue Number (this paper)
27- 31 F5.2 mag Jmag Mean J magnitude
33- 36 F4.2 mag e_Jmag J standard deviation
38- 42 F5.2 mag Hmag Mean H magnitude
44- 47 F4.2 mag e_Hmag H standard deviation
49- 53 F5.2 mag Ksmag Mean Ks magnitude
55- 58 F4.2 mag e_Ksmag Ks standard deviation
60- 63 F4.2 mag J-Ks J-Ks colour index
65- 66 I2 --- o_Jmag Number of J observations averaged
68- 69 I2 --- o_Hmag Number of H observations averaged
71- 72 I2 --- o_Ksmag Number of Ks observations averaged
74 I1 --- Note [1/2]? Possible Mira (1)
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Note (1): Notes as follows:
1 = N12070 is probably a Mira, with ΔKs<0.6mag, and possible periods
around 545 or 215d, but its image is confused at shorter wavelengths
2 = N40419 is a Mira with a period of 193d, but its photometry is
contaminated by nearby sources
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Byte-by-byte Description of file: table4a.dat table4b.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Right ascension (J2000)
11- 19 F9.5 deg DEdeg Declination (J2000)
21- 25 I5 --- Seq [10001/40643] Catalogue Number (this paper)
27- 29 I3 d Per Period
31- 35 F5.2 mag Jmag Fourier mean J magnitude
37- 41 F5.2 mag Hmag Fourier mean H magnitude
43- 47 F5.2 mag Ksmag Fourier mean Ks magnitude
49- 52 F4.2 mag Jamp ?=- Peak-to-peak amplitude in J of the
best-fitting first-order sine curve
54- 57 F4.2 mag Hamp Peak-to-peak amplitude in H of the
best-fitting first-order sine curve
59- 62 F4.2 mag Ksamp Peak-to-peak amplitude in Ks of the
best-fitting first-order sine curve
64- 67 A4 --- SpType Spectral type (1)
69 A1 --- Note Note (2)
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Note (1): shows those with spectral types, or narrow-band spectral indices
(Letarte et al. 2002, Cat. J/AJ/123/832)
Note (2): Notes as follows:
a = N10091 was identified as a late-M star with Hα emission by
Filippenko & Chornock (2003IAUC.8158....4F 2003IAUC.8158....4F)
* = Low Ks amplitude (<0.4 mag) for a Mira
1 = Spectral type from Kacharov et al. (2012, Cat. J/A+A/537/A108)
2 = N20558 was not used in the PL analysis as its image appears blended.
3 = N20840 has only four good observations at J; therefore, its mean is
uncertain and its amplitude unknown
4 = N30583 has seven observations only; P taken from Battinelli & Demers
(2011A&A...525A..69B 2011A&A...525A..69B)
5 = N21029 has a long-term trend (see Fig. A2), mean given here for
bright cycle
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq [10001/40643] Catalogue Number (this paper)
7- 9 I3 d Per Period
10 A1 --- u_Per Uncertainty flag on Per
12- 16 F5.2 mag Ksmag Ks magnitude
18- 19 I2 --- [BD2011] [1/20] Battinelli & Demers (2011A&A...525A..69B 2011A&A...525A..69B)
number
21- 24 I4 d Per2 Period from Battinelli & Demers
(2011A&A...525A..69B 2011A&A...525A..69B)
26- 30 F5.2 mag Ksmag2 Ks magnitude from Battinelli & Demers
(2011A&A...525A..69B 2011A&A...525A..69B)
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq [10001/40643] Catalogue Number (this paper)
7- 9 I3 d Per Period
11- 15 F5.2 mag mbol Bolometric apparent magnitude
17- 20 F4.2 mag (J-Ks)0 Deredenned J-Ks colour index
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 31-Jan-2014