J/AJ/127/2771 HST proper-motions of M4 main-sequence stars (Richer+, 2004)
Hubble space telescope observations of the main sequence of M4.
Richer H.B., Fahlman G.G., Brewer J., Davis S., Kalirai J., Stetson P.B.,
Hansen B.M.S., Rich R.M., Ibata R.A., Gibson B.K., Shara M.
<Astron. J., 127, 2771-2792 (2004)>
=2004AJ....127.2771R 2004AJ....127.2771R
ADC_Keywords: Clusters, globular ; Stars, dwarfs ; Proper motions
Keywords: globular clusters: general - globular clusters: individual (M4)
Abstract:
We present new results from a photometric study of the main-sequence
stars in M4 (NGC 6121=C1620-264), the closest globular cluster to the
Sun. Multifield, multiepoch observations at approximately 1, 2, and 6
core radii were obtained with WFPC2 on the Hubble Space Telescope
through either the F606W filter or the F555W (V) and F814W (I)
filters. The multi-epoch observations allowed us to clean the data on
the basis of proper motion and thus separate cluster from field stars
or extragalactic objects.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 46 16 Exposure Record
table4.dat 47 620 Annulus 1: Photometry and Astrometry
table5.dat 47 1006 Annulus 2: Photometry and Astrometry
table6.dat 47 623 Annulus 3: Photometry and Astrometry
table7.dat 47 630 Annulus 4: Photometry and Astrometry
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See also:
J/ApJS/120/265 : HST photometry of M4 (Ibata+, 1999)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1 I1 --- Field Field number in radius core
3- 6 I4 yr Date Year of the observation
8- 11 I4 --- PID Program identification number of the observation
13- 17 A5 --- Filt Filter
19- 22 I4 s ExpTime Exposure time
24- 26 I3 --- Frames Number of frames
28- 46 A19 --- Com Comments
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Byte-by-byte Description of file: table[4-7].dat
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Bytes Format Units Label Explanations
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1- 8 F8.4 deg RAdeg Right ascension in decimal degrees (J2000)
10- 17 F8.4 deg DEdeg Declination in decimal degrees (J2000)
19- 24 F6.3 mag F555W [19/34] The F555W-band magnitude
26- 31 F6.3 mag F814W [17/28] The F814W-band magnitude
33- 39 F7.3 mas/yr pmRA Right ascension proper motion times
the cosine of the declination (1)
41- 47 F7.3 mas/yr pmDE Declination proper motion (1)
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Note (1): Measured with respect to an extragalactic reference frame
(Kalirai et al., 2003AJ....126.1402K 2003AJ....126.1402K).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 08-Jul-2004