J/AJ/106/154 HST Observations in inner region of M15 (Ferraro+ 1993)
Hubble Space Telescope / Faint Object Camera observations of the
inner regions of the galactic globular cluster M15.
Ferraro F.R., Paresce F.
<Astron. J. 106, 154 (1993)>
=1993AJ....106..154F 1993AJ....106..154F
ADC_Keywords: Clusters, globular ; Photometry, ultraviolet
Abstract:
A set of high resolution images of the core of the Galactic Globular
Cluster M15 (NGC 7078) were obtained for the first time with the Faint
Object Camera on Hubble Space Telescope through the f/48-F140W,
f/48-F220W and f/96-F342W ultraviolet filters. Two UV-Color-Magnitude
Diagrams are presented for the ∼3000 objects measured in the 22"x22"
field centered on the core covered by our observations. Out of these,
19 are variables discovered from the rms frame-to-frame scatter of the
F220W images, 14 of which are probably RR Lyrae. The existence of the
gap on the Horizontal Branch (HB) separating the bulk of the HB stars
from the Blue Tail already known for the outer parts of the cluster,
is confirmed for the core regions. The temperature and the mass
distribution of the HB stars is derived from the ultraviolet
color-color diagram. We also detect a well developed Blue Straggler
sequence. At least two of the brighter blue stragglers reside within
the sharp core.
Objects:
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RA (2000) DE Designation(s)
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21 29 58.2 +12 10 02 M 15 = NGC 7078 = C 2127+119
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 48 280 Non-variable stars in the observed field
table2 59 19 Variable stars in the observed field
table3 31 9 Candidate Blue Stragglers stars in M15
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See also:
J/AJ/107/1745 : HST UVI photometry of M15. II. (Yanny+, 1994)
J/AJ/107/2067 : Fabry-Perot measurements of M15 (Gebhardt+, 1994)
J/AJ/110/704 : RR Lyrae in M15 (Silbermann+ 1995)
J/ApJ/347/251 : Dynamics of Globular Cluster M15 (Peterson+ 1989)
Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 3 I3 --- Name [1/280]+ Star sequence number
9- 12 F4.1 mag m140 []? Magnitude at 140 nm
17- 20 F4.1 mag m220 []? Magnitude at 220 nm
25- 28 F4.1 mag m342 []? Magnitude at 340 nm
33- 35 I3 pix X X coordinate
41- 43 I3 pix Y Y coordinate
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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1- 3 A3 --- Vname Variable star sequence number
9- 18 A10 --- Type Star type
25- 28 F4.1 mag m140 []? Magnitude at 140 nm
33- 36 F4.1 mag m220 Magnitude at 220 nm
41- 44 F4.1 mag m342 []? Magnitude at 340 nm
49- 51 I3 pix X X coordinate
57- 59 I3 pix Y Y coordinate
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Byte-by-byte Description of file: table3
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Bytes Format Units Label Explanations
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1- 3 A3 --- BSname Blue Stragglers candidate sequence number
9- 11 I3 --- Name Star sequence number of table1
18- 22 F5.2 mag m220 Magnitude at 220 nm
27- 31 F5.2 mag m220-m342 Color index
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History: Prepared at CDS
(End) Francois Ochsenbein, Patricia Bauer [CDS] 05-Jul-1994