J/AJ/135/2141 F814W+F606W photometry of NGC 6397 faint stars (Richer+, 2008)
Deep advanced camera for surveys imaging in the globular cluster NGC 6397:
the cluster color-magnitude diagram and luminosity function.
Richer H.B., Dotter A., Hurley J., Anderson J., King I., Davis S.,
Fahlman G.G., Hansen B.M.S., Kalirai J., Paust N., Rich R.M., Shara M.M.
<Astron. J., 135, 2141-2154 (2008)>
=2008AJ....135.2141R 2008AJ....135.2141R
ADC_Keywords: Clusters, globular ; Stars, faint ; Photometry, HST
Keywords: Galaxy: halo - globular clusters: individual (NGC 6397) -
stars: low-mass, brown dwarfs -
stars: luminosity function, mass function - stars: Population II -
white dwarfs
Abstract:
We present the color-magnitude diagram (CMD) from deep Hubble Space
Telescope imaging in the globular cluster NGC 6397. The Advanced
Camera for Surveys (ACS) was used for 126 orbits to image a single
field in two colors (F814W, F606W) 5' SE of the cluster center. The
field observed overlaps that of archival WFPC2 data from 1994 and 1997
which were used to proper motion (PM) clean the data. Applying the PM
corrections produces a remarkably clean CMD which reveals a number of
features never seen before in a globular cluster CMD. In our field,
the main-sequence stars appeared to terminate close to the location in
the CMD of the hydrogen-burning limit predicted by two independent
sets of stellar evolution models.
Objects:
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RA (2000) DE Designation(s)
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17 40 41.4 -53 40 25 NGC 6397 = C 1736-536
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 42 2324 Photometry of proper motion selected NGC 6397
cluster stars
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See also:
J/A+A/287/769 : UV photometry of NGC 6397 (Burgarella+ 1994)
J/ApJS/99/637 : Equivalent widths for 54 red giants (Norris+ 1995)
J/PASP/108/682 : Low-Mass Stars in Outer Field in NGC 6397 (Mould+, 1996)
J/A+AS/122/1 : BV photometry of variables in NGC 6397 (Kaluzny, 1997)
J/AJ/119/1225 : Stroemgren photometry of Omega Cen and NGC 6397 (Hughes+ 2000)
J/A+A/425/509 : VI photometry of NGC 6397 (Andreuzzi+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.2 pix Xpos The X pixel coordinate (1)
9- 14 F6.1 pix Ypos The Y pixel coordinate (1)
16- 20 F5.2 mag F814W The F814W band VEGAMAGS magnitude (2)
22- 30 F9.6 mag F606W-F814W The (F606W-F814W) color index (2)
32- 36 F5.2 pix dx The X pixel shift (3)
38- 42 F5.2 pix dy The Y pixel shift (3)
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Note (1): As they appear on the reference frame j97101bbq.flt. Sources
identified as [RDH2008] xxx.x+yyyy.y in Simbad.
Note (2): Calibrated according to Sirianni et al. (2005PASP..117.1049S 2005PASP..117.1049S).
Note (3): In position of the star over a 10 year period with respect to the
cluster. The ACS pixels are 0.05" on a side.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 12-Jan-2011