J/PASP/117/37 BVRI photometry in NGC 2419, Pal 4, and Pal 14 (Saha+, 2005)
Faint BVRI photometric sequences in selected fields.
Saha A., Dolphin A.E., Thim F., Whitmore B.
<Publ. Astron. Soc. Pac., 117, 37-78 (2005)>
=2005PASP..117...37S 2005PASP..117...37S
ADC_Keywords: Photometry, UBVRI ; Clusters, globular ; Photometry, Cousins
Abstract:
The results from work done to extend the Johnson-Cousins BVRI
photometric standard sequence to faint levels of V∼21mag in compact
fields is presented. Such calibration and extension of sequences is
necessary to fill a calibration gap if reliable photometry from modest
aperture telescopes in space (e.g., the Hubble Space Telescope) or
terrestrial telescopes with apertures exceeding 4m is to be done.
Sequences like the ones presented here, which cover a large range in
brightness as well as color, will allow photometric calibration to be
done efficiently and will also make such work less prone to systematic
sources of error. Photometry of stars in approximately 10'x10' fields
around three globular clusters (NGC 2419, Pal 4, and Pal 14) are
presented from data acquired over several photometric nights. In each
field, several stars are measured in B, V, R, and I passbands, with
standard errors in the mean less than 0.015mag from random errors, to
levels fainter than V=21mag.
Description:
Observations were made primarily with the WIYN 3.5m telescope at the
Kitt Peak National Observatory. In addition, our target fields and
standard stars were also observed at the WIYN 0.9m telescope at Kitt
Peak. Observations of NGC 2419, Pal 4, and Pal 14, all of which are
distant globular clusters in our galaxy and have the additional virtue
of having been observed repeatedly with the WFPC2 camera of the HST,
were made on nights that appeared to be cloudless.
Objects:
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RA (2000) DE Designation(s)
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07 38 08.5 +38 52 55 NGC 2419 = C 0734+390
11 29 16.8 +28 58 25 Pal 4 = UGCA 237
16 10 59.0 +14 57 42 Pal 14 = GCl 38
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 145 3989 Stars in the NGC 2419 field with at least V and
I photometry
table7.dat 145 624 Stars in the Pal 4 field with at least V and I
photometry
table10.dat 145 1651 Stars in the Pal 14 field with at least V and I
photometry
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See also:
J/AJ/117/247 : Ages for globular clusters in the halo (Stetson+, 1999)
Byte-by-byte Description of file: table4.dat table7.dat table10.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 pix Xpos X position
10- 17 F8.3 pix Ypos Y position
19- 20 I2 h RAh Hour of Right Ascension (J2000.0) (1)
22- 23 I2 min RAm Minute of Right Ascension (J2000.0) (1)
25- 29 F5.2 s RAs Second of Right Ascension (J2000.0) (1)
30 A1 --- DE- Sign of the Declination (J2000.0) (1)
31- 32 I2 deg DEd Degree of Declination (J2000.0) (1)
34- 35 I2 arcmin DEm Arcminute of Declination (J2000.0) (1)
37- 40 F4.1 arcsec DEs Arcsecond of Declination (J2000.0) (1)
42- 47 F6.3 mag Vmag Mean V magnitude
49- 53 F5.3 mag e_Vmag Error in Vmag
55- 56 I2 --- o_Vmag Number of observations of Vmag
58- 65 F8.2 --- VChi2 ? Reduced χ^2 (I band)
67- 72 F6.3 mag Imag Mean I magnitude
74- 78 F5.3 mag e_Imag Error in Imag
80- 81 I2 --- o_Imag Number of observations of Imag
83- 89 F7.2 --- IChi2 ? Reduced χ^2 (I band)
91- 96 F6.3 mag Rmag ? Mean R magnitude
98-102 F5.3 mag e_Rmag ? Error in Rmag
104-105 I2 --- o_Rmag ? Number of observations of Rmag
107-114 F8.2 --- RChi2 ? Reduced χ^2 (R band)
116-122 F7.3 mag Bmag ? Mean B magnitude
124-129 F6.3 mag e_Bmag ? Error in Bmag
131-132 I2 --- o_Bmag ? Number of observations of Bmag
134-141 F8.2 --- BChi2 ? Reduced χ^2 (B band)
143-145 A3 --- SDT SDT identification number (2)
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Note (1): Designations in Simbad:
[SDT2005] NGC 2419 JHHMMSS.ss+DDMMSS.s in table4.dat
[SDT2005] Pal 4 JHHMMSS.ss+DDMMSS.s in table7.dat
[SDT2005] Pal 14 JHHMMSS.ss+DDMMSS.s in table10.dat
Note (2): NNN for star with best photometry, VNN for likely variable star.
Designations in Simbad:
Cl* NGC 2419 SDT NNN in table4.dat
Cl* NGC 2419 SDT VNN in table4.dat
Cl* Palomar 4 SDT NN in table7.dat
Cl* Palomar 4 SDT VN in table7.dat
Cl* Palomar 14 SDT NNN in table10.dat
Cl* Palomar 14 SDT VN in table10.dat
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 03-Feb-2006