J/AJ/139/1871 Kinematics of globulars in NGC 5128 (Woodley+, 2010)
The kinematics of the globular cluster system of NGC 5128 with a new large
sample of radial velocity measurements.
Woodley K.A., Gomez M., Harris W.E., Geisler D., Harris G.L.H.
<Astron. J., 139, 1871-1888 (2010)>
=2010AJ....139.1871W 2010AJ....139.1871W
ADC_Keywords: Clusters, globular ; Radial velocities ; Galaxies, nearby
Keywords: catalogs - galaxies: elliptical and lenticular, cD - galaxies:
individual (NGC 5128) - galaxies: kinematics and dynamics - galaxies:
star clusters: general - globular clusters: general -
planetary nebulae: general
Abstract:
New radial velocity measurements for previously known and newly
confirmed globular clusters (GCs) in the nearby massive galaxy
NGC 5128 are presented. We have obtained spectroscopy from
LDSS-2/Magellan, VIMOS/Very Large Telescope, and HYDRA/Cerro Tololo
Inter-American Observatory from which we have measured the radial
velocities of 218 known, and identified 155 new, GCs. The current
sample of confirmed GCs in NGC 5128 is now 605 with 563 of these
having radial velocity measurements, the second largest kinematic
database for any galaxy. We have performed a new kinematic analysis of
the GC system that extends out to 45' in galactocentric radius. We
have examined the systemic velocity, projected rotation amplitude and
axis, and the projected velocity dispersion of the GCs as functions of
galactocentric distance and metallicity.
Description:
We obtained multi-object slit spectroscopy with the spectrograph-2
(LDSS-2) on the Baade/Magellan 6.5m telescope at the Las Campanas
Observatory in Chile. We observed 12 fields scattered around the
central regions of NGC 5128 on 2002 May 9-10 (PI: D. Geisler) with the
6' field of view of LDSS-2.
We obtained spectroscopy with the VIMOS MOS/Very Large Telescope (VLT)
8m telescope in 2007 (PI: M. Gomez, Program ID 079.D-0539), on
Paranal, Chile.
We obtained spectroscopy from the HYDRA Spectrograph on the Cerro
Tololo Inter-American Observatory (CTIO) Blanco 4m telescope, in
Chile (PI: W. Harris, Program ID 2007A-0070). We observed from 2007
April 7 to April 10 and had 2.5 usable nights of data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 71 218 Radial velocity measurements of previously
confirmed Globular Clusters in NGC 5128
table3.dat 103 155 Radial velocity measurements of newly confirmed
Globular Clusters in NGC 5128
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See also:
J/ApJ/708/1335 : Spectroscopy of GCs in NGC 5128 (Woodley+, 2010)
J/AJ/140/2101 : NGC 5128 globular clusters photometry (Sinnott+, 2010)
J/MNRAS/386/1443 : 2dF study of globular clusters in NGC 5128 (Beasley+, 2008)
J/AJ/134/494 : NGC 5128 globular clusters UBVRICMT1 phot. + RV (Woodley+,
2007)
J/AJ/132/2187 : MCT1 photometry of NGC 5128 GCs (Harris+, 2006)
J/AJ/128/712 : Washington Photometry in NGC 5128 (Harris+, 2004)
J/ApJS/150/367 : Globular clusters in NGC 5128 (Peng+, 2004)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- [WHB2007] Globular cluster identification
8- 9 I2 h RAh Hour of Right Ascension (J2000)
11- 12 I2 min RAm Minute of Right Ascension (J2000)
14- 18 F5.2 s RAs Second of Right Ascension (J2000)
20 A1 --- DE- Sign of the Declination (J2000)
21- 22 I2 deg DEd Degree of Declination (J2000)
24- 25 I2 arcmin DEm Arcminute of Declination (J2000)
27- 31 F5.2 arcsec DEs Arcsecond of Declination (J2000)
33- 35 I3 km/s VLDSS2 ? LDSS-2/Magellan radial velocity
37- 39 I3 km/s e_VLDSS2 ? Uncertainty in VLDSS2
41 A1 --- f_VLDSS2 Average of discordant values (1)
43- 45 I3 km/s VVIMOS ? VIMOS/VLT radial velocity
47- 49 I3 km/s e_VVIMOS ? Uncertainty in VVIMOS
51 A1 --- f_VVIMOS Average of discordant values (1)
53- 55 I3 km/s VHydra ? Hydra/CTIO radial velocity
57- 59 I3 km/s e_VHydra ? Uncertainty in VHydra
61 A1 --- f_VHydra Average of discordant values (1)
63- 65 I3 km/s Vrad New weighted radial velocity (2)
67- 69 I3 km/s e_Vrad Uncertainty in Vrad
71 A1 --- f_Vrad Discordant values of Vrad (1)
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Note (1): Flag as follows:
a = The weighted average of two radial velocity measurements with
LDSS-2, 610±66km/s and 485±69km/s.
b = The weighted average of three radial velocity measurements with
Hydra, 563±47km/s, 555±26km/s, and 530±28km/s.
c = The weighted average of two radial velocity measurements with
Hydra, 760±18km/s and 772±23km/s.
d = The weighted average of two radial velocity measurements with
LDSS-2, 691±44km/s and 693±49km/s.
e = The weighted average of two radial velocity measurements with
LDSS-2, 566±46km/s and 495±34km/s.
f = The weighted average of two radial velocity measurements with
Hydra, 457±17km/s and 432±21km/s.
g = The weighted average of three radial velocity measurements with
Hydra, 580±44km/s, 535±67km/s, and 594±20km/s.
h = The weighted average of two radial velocity measurements with
LDSS-2, 465±51km/s and 524±28km/s.
i = The weighted average of two radial velocity measurements with
Hydra, 600±47km/s and 508±31km/s.
j = This object was originally classified as a GC from a Hubble Space
Telescope study by Harris et al. (2006, Cat. J/AJ/132/2187). This is
the first radial velocity measurement of this object, and it has a
greater than 0.8 correlation peak for the recorded velocity, indicating
it may be a star and not a genuine GC.
k = The weighted average of two radial velocity measurements with
Hydra, 634±29km/s and 615±50km/s.
l = The weighted average of two radial velocity measurements with
VIMOS, 392±18km/s and 427±19km/s.
m = The weighted average of three radial velocity measurements with
Hydra, 458±23km/s, 461±29km/s, and 460±17km/s.
n = The weighted average of two radial velocity measurements with
Hydra, 601±29km/s and 596±30km/s.
o = The weighted average of three radial velocity measurements with
Hydra, 417±40km/s, 413±14km/s, and 409±28km/s.
Note (2): The new weighted velocity measurement of all GCs in the past
literature combined with the new measurements of this study:
van den Bergh et al. 1981AJ.....86...24V 1981AJ.....86...24V;
Hesser et al. 1984ApJ...276..491H 1984ApJ...276..491H, 1986ApJ...303L..51H 1986ApJ...303L..51H;
Harris et al. 1992AJ....104..613H 1992AJ....104..613H;
Peng et al. 2004, Cat. J/ApJS/150/367;
Woodley et al. 2005AJ....129.2654W 2005AJ....129.2654W, 2010ApJ...708.1335W 2010ApJ...708.1335W;
Rejkuba et al. 2007A&A...469..147R 2007A&A...469..147R;
Beasley et al. 2008, Cat. J/MNRAS/386/1443)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- [WHB2007] Globular cluster identification
8 A1 --- f_[WHB2007] [b] indicates new globular cluster but with
caution (1)
10- 11 I2 h RAh Hour of Right Ascension (J2000)
13- 14 I2 min RAm Minute of Right Ascension (J2000)
16- 20 F5.2 s RAs Second of Right Ascension (J2000)
22 A1 --- DE- Sign of the Declination (J2000)
23- 24 I2 deg DEd Degree of Declination (J2000)
26- 27 I2 arcmin DEm Arcminute of Declination (J2000)
29- 32 F4.1 arcsec DEs Arcsecond of Declination (J2000)
34- 38 F5.2 mag Cmag ? Washington/C band magnitude (1)
40- 43 F4.2 mag e_Cmag ? Error in Cmag
45- 49 F5.2 mag Mmag Washington/M band magnitude (1)
51- 54 F4.2 mag e_Mmag Error in Mmag
56- 60 F5.2 mag T1mag Washington/T1 band magnitude (1)
62- 65 F4.2 mag e_T1mag Error in T1mag
67- 69 I3 km/s VLDSS2 ? LDSS-2/Magellan radial velocity
71- 73 I3 km/s e_VLDSS2 ? Uncertainty in VLDSS2
75- 77 I3 km/s VVIMOS ? VIMOS/VLT radial velocity
79- 81 I3 km/s e_VVIMOS ? Uncertainty in VVIMOS
83- 86 I4 km/s VHydra ? Hydra/CTIO radial velocity
88- 90 I3 km/s e_VHydra ? Uncertainty in VHydra
92 A1 --- f_VHydra [d] Flag on VHydra (2)
94- 97 I4 km/s Vrad New weighted radial velocity (3)
99-101 I3 km/s e_Vrad Uncertainty in Vrad
103 A1 --- f_Vrad [ac] Flag on VRad (2)
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Note (1): From Harris et al. (2004, Cat. J/AJ/128/712)
Note (2): Flag as follows:
a = A second strong correlation peak was found at 182±31km/s.
b = Structural parameter measurements indicate the object may be a star.
c = A second strong correlation peak was found at 103±106km/s.
d = The weighted velocity of two measurements with Hydra, 539±50km/s
and 510±29km/s.
Note (3): The weighted average of all radial velocity measurements of
these new globular clusters.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Jul-2011