J/AJ/110/2788 JHK photometry for Galactic bulge stars (Tiede+ 1995)
Implications of new JHK photometry and a deep infrared luminosity
function for the galactic bulge.
Tiede G.P., Frogel J.A., Terndrup D.M.
<Astron. J. 110, 2788 (1995)>
=1995AJ....110.2788T 1995AJ....110.2788T (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, infrared
Description:
We present deep near-IR photometry for Galactic bulge stars in Baade's
Window, (l, b)=(1.0deg, -3.9deg), and another minor axis field at
(l, b)=(0deg, -6deg). We combine our data with previously published
photometry and construct a luminosity function over the range
5.5=<K0=<16.5, deeper than any previously published. The slope of this
luminosity function and the magnitude of the tip of the first ascent
giant branch are consistent with theoretical values derived from
isochrones with appropriate age and metallicity. We use the
relationship between [Fe/H] and the giant branch slope derived from
near-IR observations of metal-rich globular clusters by Kuchinski et
al. (1995AJ....109.1131K 1995AJ....109.1131K) to calculate the mean metallicity for
several bulge fields along the minor axis.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 43 172 BW4a data
table4.dat 54 509 BW4b data
table5.dat 36 131 BW6 data
table6.dat 49 40 Summary of the BW4 artificial frame
tables.tex 151 1203 LaTeX version of the tables
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See also:
J/ApJ/353/494 : JHKL photometry on Galactic bulge M Giants (Frogel+, 1990)
Byte-by-byte Description of file: table3.dat table5.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Id Identification number
5- 9 F5.1 pix Xpos X position
11- 15 F5.1 pix Ypos Y position
17- 22 F6.3 mag K0 K0 magnitude
24- 29 F6.3 mag (J-K)0 ? (J-K)0 color index
31- 36 F6.3 mag (H-K)0 ? (H-K)0 color index
38- 43 A6 --- Note Notes
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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- 3 I3 --- Id Identification number
5- 9 F5.1 pix Xpos X position
11- 15 F5.1 pix Ypos Y position
17- 22 F6.3 mag K0 K0 magnitude
24- 29 F6.3 mag (J-K)0 ? (J-K)0 color index
31- 36 F6.3 mag (H-K)0 ? (H-K)0 color index
38- 43 F6.3 mag V0 ? V0 magnitude
45- 49 F5.3 mag (V-I)0 ? (V-I)0 color index
51- 56 A6 --- Note Notes
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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- 5 F5.2 mag Kmag0 K magnitude range: lower limit
6 A1 --- --- [-]
7- 11 F5.2 mag Kmag1 K magnitude range: upper limit
13- 15 I3 --- NInput Number of stars Input
17- 18 I2 --- NDetect Number of stars Detected
20- 24 F5.1 % Complet Percent complete
26- 30 F5.3 mag DKmag ? Absolute average K magnitude difference
32- 36 F5.3 mag e_DKmag ? rms uncertainty on DKmag
38- 43 F6.3 mag DMag ? Mean difference
45- 49 F5.3 mag e_DMag ? rms uncertainty on DMag
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Table 1: Field coordinates and adopted reddening values
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Field RA (1950) DE A(K) E(H-K) E(J-K) A(V) E(V-I)
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BW4a 18 00 12 -29 59 54 0.14 0.09 0.26
BW4b 18 00 33 -30 02 36 0.14 0.09 0.26 1.46 0.65
BW6 18 08 41 -31 51 55 0.12 0.08 0.22
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Table 2: Journal of observations
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Field # of frame x Exposure Calibration
(sec) Uncertainty
J H K J H K
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BW4b 5 x 3 5 x 3 5 x 3 0.005 0.004 0.004
BW4a 4 x 3 5 x 3 5 x 3 0.030 0.029 0.061
BW4a 5 x 1 0.052
BW4b 5 x 3 5 x 3 5 x 3 0.056 0.048 0.097
BW4b 5 x 3 5 x 3 4 x 3 0.046 0.051 0.045
BW4b 9 x 60 18 x 30 41 x 20 0.028 0.051 0.037
BW4b 10 x 60 29 x 20 0.034 0.016
BW4b 18 x 20 0.031
BW6 10 x 10 10 x 10 3 x 10 0.024 0.021 0.028
BW6 15 x 150 15 x 150 50 x 45 0.041 0.038 0.042
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Table 7: Giant branch slopes (solutions to (J-K)=b+a x K) and derived [Fe/H]
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Field Intercept Slope [Fe/H] |b|
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Liller 1 -0.135 ± 0.009 0.26 ± 0.38 0.20
Terzan 2 3.200 ± 0.180 -0.127 ± 0.014 0.07 ± 0.42 2.30
BW3 1.972 ± 0.123 -0.108 ± 0.013 -0.42 ± 0.33 2.70
BW4 2.001 ± 0.052 -0.113 ± 0.005 -0.28 ± 0.16 3.90
BW6 1.867 ± 0.065 -0.098 ± 0.007 -0.65 ± 0.18 6.00
BW8 1.733 ± 0.092 -0.082 ± 0.010 -1.05 ± 0.30 8.00
BW10 1.766 ± 0.135 -0.086 ± 0.014 -0.96 ± 0.37 10.25
BW12 1.937 ± 0.105 -0.108 ± 0.011 -0.40 ± 0.27 12.50
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Table 8. Metallicity for various latitudes.
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Mean metallicities <[Fe/H]> from:
---------------------------------------------
Field |b| This Terndrup Frogel Tyson McWilliam Average
study (1988) (1990) (1991) (1994)
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Liller 1 0.20 0.26 0.26
error 0.38 0.38
Terzan 2 2.30 0.07 0.07
error 0.42 0.42
BW3 2.70 -0.42 0.20 -0.41 -0.21
error 0.33 0.20 0.76 0.17
BW4 3.90 -0.28 -0.17 0.04 -0.19 -0.27 -0.17
error 0.16 0.13 0.22 0.70 0.40 0.09
BW6 6.00 -0.65 -0.40 -0.09 0.21 -0.23
error 0.18 0.09 0.16 0.60 0.07
BW8 8.00 -1.05 -0.60 -0.02 -0.74 -0.60
error 0.30 0.11 0.23 1.00 0.09
BW10 10.25 -0.96 -0.88 -0.20 -0.38 -0.61
error 0.37 0.12 0.21 0.71 0.10
BW12 12.50 -0.40 -0.22 -1.02 -0.55
error 0.27 0.22 0.54 0.16
BW17 17.30 -1.35 -1.35
error 0.30 0.30
-------------------------------------------------------------
Slope -0.060 -0.113 -0.038 -0.094 -0.071
error 0.033 0.004 0.010 0.019 0.017
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Notes on columns:
Terndrup (1988): <[Fe/H]> values have been lowered by -0.15
to correct to R0=8.0Kpc (as suggested in Terndrup 1988)
Frogel et al. (1990): <[Fe/H]> values had the 30% correction
applied as suggested in Frogel et al. (1990).
Tyson (1991): Tyson (1991) calibrated his values using a subset
of the bulge stars from Rich (1988). McWilliam & Rich (1994)
has since recalibrated these stars, lowering the average
[Fe/H] by -0.32. This correction was applied to the values
from Tyson (1991).
Average: The Average is an unweighted mean since the
uncertainties from the studies were not calculated
identically. The uncertainty in the Average is the formal
standard deviation in the mean.
Slope: This line contains Slope in dex/degree. Slopes and
associated uncertainties were calculated by least squares
fits through the data points. The Average is a least squares
fit through all of the data points combined.
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Table 9: Studies determining Y (Helium abundance) for bulge stars
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Reference Y Notes
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This Study 0.30 ±0.03 Without first ascent bump correction (R' method)
0.27 ±0.03 With first ascent bump correction (R' method)
Terndrup (1988) 0.32 ±0.05 Including blue HB stars (R method)
0.30 ±0.05 Excluding blue HB stars (R method)
Minniti (1995) 0.28 ±0.02 Including an AGB Correction (R' method)
Renzini (1994) 0.30 - 0.35 (Rc method)
Davidge (1991) ∼0.12 Davidge only reports an R and R' value not a Y.
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Courtesy: Glenn Tiede
References:
Frogel J.A. et al., 1990, ApJ 353, 494 =Cat J/ApJ/353/494
McWilliam A. & Rich R.M., 1994, ApJS 91, 749 =1994ApJS...91..749M 1994ApJS...91..749M
Rich R.M., 1988, AJ 95, 828 =1988AJ.....95..828R 1988AJ.....95..828R
Terndrup D.M., 1988, AJ 96, 884 =1988AJ.....96..884T 1988AJ.....96..884T
Tyson N.D., 1991, ApJ 373, L1 =1991ApJ...373L...1T 1991ApJ...373L...1T
(End) Patricia Bauer [CDS] 07-Aug-1996