J/AJ/119/1268 CFHT adaptive optics observations of M15 (Gebhardt+, 2000)
Canada-France-Hawaii telescope adaptive optics observations of the central
kinematics in M15
Gebhardt K., Pryor C., O'Connell R.D., Williams T.B., Hesser J.E.
<Astron. J. 119, 1268 (2000)>
=2000AJ....119.1268G 2000AJ....119.1268G
ADC_Keywords: Clusters, globular ; Radial velocities
Keywords: celestial mechanics, stellar dynamics - globular clusters:
individual (M15) galaxies: distances and redshifts - instrumentation:
adaptive optics
Abstract:
We have used an Imaging Fabry-Perot Spectrophotometer with the
Adaptive Optics Bonnette on the Canada-France-Hawaii Telescope to
measure stellar radial velocities in the globular cluster M15 (NGC
7078). An average seeing of 0.15'' FWHM, with the best-seeing image
having 0.09'', allowed us to measure accurately the velocities for
five stars within 1'' of the center of M15. Our estimate of the second
moment of the velocity distribution (i.e., the dispersion, ignoring
rotation) inside a radius of 2'' is 11.5 km.s-1, the same value we
find out to a radius of about 6''. However, the projected net rotation
does increase dramatically at small radii, as our previous
observations led us to suspect. The rotation amplitude inside a radius
of 3.4'' is v=10.4±2.7 km.s-1 and the dispersion after removing
the rotation is σ=10.3±1.4 km.s-1, so v/σ ∼ 1 in
this region. In addition, the position angle of the projected rotation
axis differs by 100 degrees from that of the net cluster rotation at
larger radii.
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------
21 29 58.4 +12 10 01 M15 = NGC 7078
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 62 1777 M15 stellar velocity results
table2.dat 124 614 M15 multiple velocity measurements
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See also:
J/ApJ/347/251 : Dynamics of the globular cluster M15 (Peterson+ 1989)
J/AJ/106/154 : HST Observations in inner region of M15 (Ferraro+ 1993)
J/AJ/107/1745 : HST UVI photometry of M15. II. (Yanny+, 1994)
J/AJ/107/2067 : Fabry-Perot measurements of M15 (Gebhardt+, 1994)
J/A+AS/119/307 : Position in M15 (Le Campion+, 1996)
J/AJ/113/1026 : Fabry-Perot Observations of M15 (Gebhardt+ 1997)
J/AJ/115/708 : Radial Velocities in the Field of M15 (Drukier+ 1998)
J/AJ/124/3255 : UBV photometry in M15 (van der Marel+, 2002)
J/ApJ/595/187 : Proper motions in M15 (McNamara+, 2003)
J/ApJ/602/264 : Proper motions and radial velocities in M15 (Mcnamara+, 2004)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- VGG Identification number from the WFPC2
photometry of Guhathakurta et al. (2000)
6 A1 --- T2 [*] when the star is also in table 2.
9- 15 F7.3 arcmin EWoff East-West offset
17- 23 F7.3 arcmin NSoff North-South offset
25- 30 F6.1 km/s Vel Mean radial velocity
33- 36 F4.1 km/s e_Vel Uncertainty in Vel
41- 45 F5.2 mag Vmag V band magnitude
49- 53 F5.3 % Prob ? Probability of the chi2 from the multiple
measurements exceeding the observed value
by chance
57- 64 A8 --- OID Identification by Auriere & Cordoni
(1981A&A...100..307A 1981A&A...100..307A)
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- VGG Identification number from the WFPC2
photometry of Guhathakurta et al. (2000)
8- 13 F6.1 km/s FP95 ? Velocity from Fabry-Perot observations
obtained in 1995
17- 19 F3.1 km/s e_FP95 ? Uncertainty in FP95
23- 28 F6.1 km/s FP94 ? Velocity from Fabry-Perot observations
obtained in 1994
31- 34 F4.1 km/s e_FP94 ? Uncertainty in FP94
38- 43 F6.1 km/s FP92 ? Velocity from Fabry-Perot observations
obtained in 1992
47- 49 F3.1 km/s e_FP92 ? Uncertainty in FP92
53- 58 F6.1 km/s FP91 ? Velocity from Fabry-Perot observations
obtained in 1991
62- 64 F3.1 km/s e_FP91 ? Uncertainty in FP91
68- 73 F6.1 km/s PSC ? Velocity from Peterson et al.
(1989ApJ...347..251P 1989ApJ...347..251P)
77- 79 F3.1 km/s e_PSC ? Uncertainty in PSC
83- 88 F6.1 km/s FP98 ? Velocity from Fabry-Perot observations
obtained in 1995
91- 94 F4.1 km/s e_FP98 ? Uncertainty in FP98
98-103 F6.1 km/s D98 ? Velocity from Drukier et al.
(1998AJ....115..708D 1998AJ....115..708D)
107-109 F3.1 km/s e_D98 ? Uncertainty in D98
113-118 F6.1 km/s DM94 ? Velocity from Dubath & Meylan
(1994A&A...290..104D 1994A&A...290..104D)
122-124 F3.1 km/s e_DM94 ? Uncertainty in MD94
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History:
* 13-Apr-2000: From AJ electronic edition
* 16-Jan-2006: table1: declination of star VGG 18534, which was blank,
has been set to 1.000 (according to van der Marel+ J/AJ/124/3255)
References:
Guhathakurta, P., et al. 2000, in preparation
(End) Greg Schwarz [AAS] 13-Apr-2000