J/MNRAS/321/77 Large-amplitude variables near the Galactic Centre (Glass+, 2001)
Large-amplitude variables near the Galactic Centre.
Glass I.S., Matsumoto S., Carter B.S., Sekiguchi K.
<Mon. Not. R. Astron. Soc. 321, 77 (2001)>
=2001MNRAS.321...77G 2001MNRAS.321...77G (erratum in 2002MNRAS.336.1390G 2002MNRAS.336.1390G)
ADC_Keywords: Stars, variable ; Photometry, infrared
Keywords: surveys - stars: AGB and post-AGB - stars: variables: other -
Galaxy: centre
Abstract:
We report here the results of a 4-yr K-band (2.2mm) survey for
large-amplitude variable stars in a 24x24arcmin2 area
centred on the Galactic Centre. A total of 409 likely long-period
variables (LPVs) were detected, for which positions, amplitudes,
average magnitudes and periods were obtained whenever
possible. The surface density of LPVs is more than ten times
greater than in the Sgr I Baade window at l=-1.37°, b=-2.63°
Description:
The survey observations were made over 4 southern winters in 1994-1997.
Observing was attempted about four times each season. The PANIC
(Platinum Silicide Near-Infrared Camera) was used in conjunction
with the 0.75m telescope at Sutherland. Observations were made most
frequently at K (2.02-2.42um ahlf-maximum points) but J- and H-band
exposures (1.25 and 1.65um) were also made on several occasions.
An area of 24x24arcmin2 centred near the Galactic Centre, was divided
into 25 fields of 300x300arcsec2, so that there was an overlap of
15arcsec between adjacent fields. The exposures were usually 5min at
first, but were increased to 10min during the latter two seasons,
when a less sensitive array was in use.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 28 25 Survey field centres
table2.dat 53 421 Large-amplitude variables found in the survey field
table3.dat 44 16 Wood et al. (1998A&A...336..925W 1998A&A...336..925W, table3) stars
in the survey area
table4.dat 125 12 Objects found twice in the survey
(because of overlapping fields)
table5.dat 72 108 Result of searches for all known OH/IR stars in
survey area and comparisons with previous work
table6.dat 27 61 Comparisons of OH and IR positions with
Sjouwerman et al., 1998, Cat. J/A+AS/128/35
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See also:
J/A+AS/92/43 : Radio Obs. of OH/IR stars close to Gal.Center (Lindqvist+ 1992)
J/A+AS/128/35 : New Sample of OH/IR stars (Sjouwerman+ 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Field [1/25] Field number
4- 5 I2 h RAh Right ascension (J2000)
7- 8 I2 min RAm Right ascension (J2000)
10- 13 F4.1 s RAs Right ascension (J2000)
15 A1 --- DE- Declination sign (J2000)
16- 17 I2 deg DEd Declination (J2000)
19- 20 I2 arcmin DEm Declination (J2000)
22- 23 I2 arcsec DEs Declination (J2000)
25- 28 F4.1 mag Klim K mag limit of the systematic search in the field
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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- 7 A7 --- [GMC2001] Source designation, FF-NNNN (1)
10- 11 I2 h RAh Right ascension (J2000)
13- 14 I2 min RAm Right ascension (J2000)
16- 20 F5.2 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 32 F4.1 arcsec DEs Declination (J2000)
34- 37 I4 d Per ? Period in Fourier amplitude spectrum (2)
38 A1 --- u_Per Unvertainty flag on Per
40- 44 F5.2 mag Kmag ? Simple numerical average of the K data (2)
46- 49 F4.2 mag Amp ? Peak-to-peak amplitude as determined from
the fitted light curve and rounded off to
the nearest 0.05mag. (2)
51 I1 --- Q ? Quality index (2) (G1)
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Note (1): The first part of the identification number is the subfield from
Table 1 and the second part is the DOPHOT running number.
Note (2): In a few cases, insufficient data has led to missing values for
Per, Kmag, Amp or Q.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Wood Wood et al. (1998A&A...336..925W 1998A&A...336..925W) designation
6 A1 --- n_Wood [a] Note on the star (1)
8- 11 I4 d PerW Wood et al. (1998A&A...336..925W 1998A&A...336..925W) period
13- 17 F5.2 mag KmagW Wood et al. (1998A&A...336..925W 1998A&A...336..925W) K magnitude
20- 26 A7 --- [GMC2001] This work designation
27 A1 --- n_[GMC2001] [a] Note on the star (1)
30- 32 I3 d Per ? This work period
33 A1 --- n_Per [:b] Note on Per (2)
35- 39 F5.2 mag Kmag ? This work K magnitude
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Note (1): a: These variables were not detected originally in the present
work but were looked for in specific searches of the data within 16
pixels in x and y of the positions of Wood et al. (1998A&A...336..925W 1998A&A...336..925W)
Note (2): b: This period has a slightly lower amplitude than 163d in the
periodogram.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Obj1 Name of the first object
8 A1 --- n_Obj1 Individual note on Obj1 (1)
10- 11 I2 h RA1.h Right ascension (J2000) of the first object
13- 14 I2 min RA1.m Right ascension (J2000) of the first object
16- 21 F6.3 s RA1.s Right ascension (J2000) of the first object
23- 27 F5.3 s e_RA1.s rms uncertainty on RA1s
29 A1 --- DE1.- Declination sign (J2000)m of the first object
30- 31 I2 deg DE1.d Declination (J2000) of the first object
33- 34 I2 arcmin DE1.m Declination (J2000) of the first object
36- 40 F5.2 arcsec DE1.s Declination (J2000) of the first object
42- 45 F4.2 arcsec e_DE1.s rms uncertainty on DE1s
47- 49 I3 d Per1 Period of the first object
51- 55 F5.2 mag Kmag1 Average K magnitude of the first object
57- 60 F4.2 mag Amp1 Amplitude of the first object
61- 62 I2 --- Q1 Quality of the first object (G1)
64- 70 A7 --- Obj2 Name of the second object
71 A1 --- n_Obj2 Individual note on Obj2 (1)
73- 74 I2 h RA2.h Right ascension (J2000) of the second object
76- 77 I2 min RA2.m Right ascension (J2000) of the second object
79- 84 F6.3 s RA2.s Right ascension (J2000) of the second object
86- 90 F5.3 s e_RA2.s rms uncertainty on RA2s
92 A1 --- DE2.- Declination sign (J2000)m of the second object
93- 94 I2 deg DE2.d Declination (J2000) of the second object
96- 97 I2 arcmin DE2.m Declination (J2000) of the second object
99-103 F5.2 arcsec DE2.s Declination (J2000) of the second object
105-108 F4.2 arcsec e_DE2.s rms uncertainty on DE2s
110-112 I3 d Per2 ? Period of the second object
114-118 F5.2 mag Kmag2 ? Average K magnitude of the second object
120-123 F4.2 mag Amp2 ? Amplitude of the second object
124-125 I2 --- Q2 ? Quality of the second object (G1)
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Note (1): Individual notes as follows:
a = Second most likely period is 427d.
b = Period of 462d almost equally probable.
c = Only eight data points. Period determination very uncertain,
even though Q appears superficially to be satisfactory.
d = Only a few points at the start of the program, showing a clear decline
e = Only seven data points.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 7 F7.3 deg GLON Galactic longitude of IRAS source
8- 13 F6.3 deg GLAT Galactic latitude of IRAS source
15- 21 A7 --- [GMC2001] Identification number (1)
22 A1 --- n_[GMC2001] [a] a: Possibly a misidentification with a
constant star "Noisy" data
24- 26 I3 d Per ? Period
27 A1 --- u_Per Uncertainty flag on Per
29- 33 F5.2 mag Kmag ? K magnitude
35- 40 A6 --- [WHM98] Wood (1998A&A...336..925W 1998A&A...336..925W) Identification
42- 45 I4 d PerW ? Wood (1998A&A...336..925W 1998A&A...336..925W) period
46 A1 --- n_PerW [n] n: no period given
48- 52 F5.2 mag KmagW ? Wood (1998A&A...336..925W 1998A&A...336..925W) K magnitude
54- 73 A20 --- Com Comments (2)
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Note (1): identification coded as:
nd = not detected after special search
crowd = crowding of images.
Note (2): Abbreviations used:
L = Lindqvist et al. (1992, Cat. J/A+AS/92/43).
vL = van Langevelde et al. (1993A&AS..101..109V 1993A&AS..101..109V) OH periods or no period
W = Wood, Habing & McGregor, 1998A&A...336..925W 1998A&A...336..925W, [WHM98] NNN-NNN
J = Jones et al. (1994AJ....107.1111J 1994AJ....107.1111J) periods.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- [SVW98] OH source designation
([SVW98] OH LLL.lll+B.bbb in Simbad)
14 A1 --- n_[SVW98] [abc] Note on [SVW98] (1)
16- 21 F6.3 arcsec DRA RA (Sjouwerman) - RA (this paper)
23- 27 F5.2 arcsec DDE DE (Sjouwerman) - DE (this paper)
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Note (1): Individual notes as follows:
a = Observed in an adjacent field.
b = Second possible identification.
c = Possible misidentification.
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Global Notes:
Note (G1): Q is a quality index, as follows:
0 = no obvious true periodicity
1 = probably periodic
2 = almost certainly periodic
3 = a well behaved light curve
History:
* 23-Mar-2001: From electronic version of the journal
* 29-Nov-2011: Table 2 corrected according to the erratum
(2002MNRAS.336.1390G 2002MNRAS.336.1390G); the star 11-307 which appears in the
erratum but not in the original paper was omitted.
(End) James Marcout, Patricia Bauer [CDS] 23-Mar-2001