J/AJ/132/2187 MCT1 photometry of NGC 5128 globular clusters (Harris+, 2006)
Structural parameters for globular clusters in NGC 5128.
II. Hubble Space Telescope ACS imaging and new clusters.
Harris W.E., Harris G.L.H., Barmby P., McLaughlin D.E., Forbes D.A.
<Astron. J., 132, 2187-2197 (2006)>
=2006AJ....132.2187H 2006AJ....132.2187H
ADC_Keywords: Galaxies, nearby ; Clusters, globular ; Photometry, CMT1T2V
Keywords: galaxies: elliptical and lenticular, cD -
galaxies: individual (NGC 5128) - galaxies: star clusters
Abstract:
We report the first results from an imaging program with the ACS
on the Hubble Space Telescope designed to measure the structural
characteristics of a wide range of globular clusters in NGC 5128,
the nearest giant elliptical galaxy. From 12 ACS WFC fields we have
measured a total of 62 previously known globular clusters and have
discovered 69 new high-probability cluster candidates not found in
any previous work. We present magnitudes and color indices for all of
these, along with rough measurements of their effective diameters and
ellipticities.
Description:
Our HST program 10260 was targeted at imaging many of the most massive
known GCs in both M31 and NGC 5128. The M31 material will be presented
in a later paper (P. Barmby et al. 2006, in preparation). In NGC 5128,
12 fields were imaged, centered on the clusters C3, C6, C7, C12, C14,
C18, C19, C25, C29, C30, C32, and C37 (Harris et al.,
1992AJ....104..613). We used the ACS in its Wide Field Channel (field
size 3.3" and scale 0.05"/pix), and with a total exposure time on each
field of one full orbit of 2500s divided into three equal
subexposures, in the F606W ("Wide V") filter.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 88 62 ACS/WFC data for previously known NGC 5128 clusters
table2.dat 80 69 ACS/WFC data for new NGC 5128 clusters
table3.dat 47 27 Revised coordinates for clusters from paper I,
Harris et al., 2002AJ....124.1435H 2002AJ....124.1435H
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See also:
J/ApJS/150/367 : Globular clusters in NGC 5128 (Peng+, 2004)
J/A+A/369/812 : UVKs photometry of NGC 5128 globular clusters (Rejkuba, 2001)
J/ApJ/560/675 : Chandra X-ray point sources in Cen A (Kraft+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Cluster Cluster name (1)
16- 17 I2 h RAh Hour of Right Ascension (J2000)
19- 20 I2 min RAm Minute of Right Ascension (J2000)
22- 26 F5.2 s RAs Second of Right Ascension (J2000)
28 A1 --- DE- Sign of the Declination (J2000)
29- 30 I2 deg DEd Degree of Declination (J2000)
32- 33 I2 arcmin DEm Arcminute of Declination (J2000)
35- 38 F4.1 arcsec DEs Arcsecond of Declination (J2000)
40- 44 F5.2 arcmin R Radius from NGC 5128 center
46- 50 F5.1 deg PA Azimuthal angle measured East of North
52- 57 F6.3 mag T1mag Washington system T1 (red ∼633nm) magnitude
59- 63 F5.3 mag M-T1 Washington system M-T1 color index
65- 69 F5.3 mag C-T1 ? Washington system C-T1 color index
71- 74 F4.2 --- ell The imexamine ellipticity
76- 80 F5.2 pix FWHM The imexamine Moffat-profile FWHM (2)
82- 88 A7 --- Field ACS field(s)
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Note (1): For the cluster identification numbers:
CNNN = [VHH81] NN, Harris et al. (1992AJ....104..613H 1992AJ....104..613H)
GNNN = [HGH92] GNNN, Harris et al. (1992AJ....104..613H 1992AJ....104..613H)
PFFNN = [PFF2004] gc NNN, Peng et al., (2004, Cat. J/ApJS/150/367)
WHHNNN = [WHH2005] NNN, Woodley et al. (2005AJ....129.2654W 2005AJ....129.2654W)
fN-.GCNN = [R2001b] fN.GC-NN, Rejkuba (2001, Cat. J/A+A/369/812)
AATNNNNN = [BBP2008] AATNNNNN, Beasley et al. (2006AJ....131..814B 2006AJ....131..814B) and
2008, Cat. J/MNRAS/386/1443
KNNN = [KKF2001] NNN, Kraft et al. (2001, Cat. J/ApJ/560/675)
Note (2): Conveniently, at the 3.9Mpc distance of NGC 5128, one pixel
of 0.05" corresponds to a linear scale of very close to 1pc.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Cluster Cluster name (CNNN) (1)
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 16 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- Sign of the Declination (J2000)
19- 20 I2 deg DEd Degree of Declination (J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 34 F5.2 arcmin R Radius from NGC 5128 center
36- 40 F5.1 deg PA Azimuthal angle measured East of North
42- 47 F6.3 mag T1mag Washington system T1 (red ∼633nm) magnitude
49- 53 F5.3 mag M-T1 ? Washington system M-T1 color index
55- 59 F5.3 mag C-T1 ? Washington system C-T1 color index
61- 64 F4.2 --- ell The imexamine ellipticity
66- 70 F5.2 pix FWHM The imexamine Moffat-profile FWHM (2)
72- 78 A7 --- Field ACS field(s)
80 I1 --- Note ? Additional note (3)
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Note (1): Labelled continuing with the C-numbers from Harris et al.
(1992AJ....104..613H 1992AJ....104..613H) and Paper I (2002AJ....124.1435H 2002AJ....124.1435H),
starting at C111. [VHH81] NNN in Simbad
Note (2): Conveniently, at the 3.9 Mpc distance of NGC 5128, one pixel of
0.05 arcsecond corresponds to a linear scale of very close to 1 pc.
Note (3): Note ad follows:
1 = Faint globular?
2 = Very crowded, in inner bulge region
3 = Very compact globular or possible star
4 = Possible globular, slightly elliptical
5 = Globular next to very bright star
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Cluster Cluster name (GNNN, CNNN) (1)
6- 7 I2 h RAh right ascension (J2000.0)
9- 10 I2 min RAm right ascension (J2000.0)
12- 16 F5.2 s RAs right ascension (J2000.0)
18 A1 --- DE- Declination sign (J2000.0)
19- 20 I2 deg DEd Declination (J2000.0)
22- 23 I2 arcmin DEm Declination (J2000.0)
25- 28 F4.1 arcsec DEs Declination (J2000.0)
30- 35 F6.3 mag T1mag Washington system T1 (red ∼633nm) magnitude
37- 41 F5.3 mag M-T1 Washington system M-T1 colour index
43- 47 F5.3 mag C-T1 Washington system C-T1 colour index
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Note (1): CNNN are [VHH81] NNN in Simbad, GNNN are [HGH92] GNNN in Simbad
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History:
From electronic version of the journal
References:
Harris et al., Paper I 2002AJ....124.1435H 2002AJ....124.1435H
McLaughlin et al., Paper III 2008MNRAS.384..563M 2008MNRAS.384..563M
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 24-Jul-2008