J/AJ/163/271 98 globular clusters of NGC 1291 with HST (Hixenbaugh+, 2022)
The Ancient Globular Clusters of NGC 1291.
Hixenbaugh K., Chandar R., Mok A.
<Astron. J., 163, 271 (2022)>
=2022AJ....163..271H 2022AJ....163..271H
ADC_Keywords: Galaxies; Clusters, globular; Photometry, VRI; Photometry, HST
Keywords: Spiral galaxies ; Globular star clusters
Abstract:
We present a new catalog of 81 ancient globular clusters (GCs) in the
early-type spiral (SB0/a) galaxy NGC1291. Candidates have been
selected from B, V, and I band images taken with the Hubble Space
Telescope, which also reveal 17 younger (τ≲fewx100Myr) clusters.
The luminosity function shows a peaked shape similar to that found for
GC systems in other spiral and elliptical galaxies. The ancient
clusters have a bimodal color distribution, with approximately 65%
(35%) of the population having blue (red) colors. The red, presumably
metal-rich, GCs are more centrally concentrated, as expected for a
bulge population; while the blue, presumably metal-poor, GCs are more
broadly distributed, consistent with expectations of a halo
population. The specific frequency of GCs in NGC1291 is higher than
found previously in most spiral galaxies. However, if we consider just
the blue subpopulation, we find SN,blue=0.50±0.06, quite similar
to that found for other spirals. This result supports the hypothesis
of a universal population of halo GCs in spirals. The fraction of red
GCs in NGC1291, when compared with those found in other galaxies,
suggests that these correlate with host galaxy type rather than with
host galaxy luminosity.
Description:
We use four pointings in NGC1291 taken by the Hubble Space Telescope
(HST) Advanced Camera for Surveys Wide Field Channel (ACS/WFC) in 2005
April and 2013 September. All pointings have images in three filters:
F435W (B-band), F555W or F606W (V-band), and F814 (I-band). Each field
covers an area of approximately 40000.2" or 74kpc2. At the adopted
distance of 8.9Mpc to NGC1291, the fields used cover a total area of
around 296kpc2, and the pixel scale is 43pc/arcsec.
Objects:
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RA (2000) DE Designation(s)
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03 17 18.58 -41 06 28.6 NGC 1291 = NGC 1269
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 75 98 Cluster catalog
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See also:
VII/195 : Globular Clusters in the Milky Way (Harris, 1996)
VII/202 : Globular Clusters in the Milky Way (Harris, 1997)
J/ApJS/122/431 : Star Clusters in M33 (Chandar+, 1999)
J/A+AS/139/393 : Young Massive Star Clusters. II. (Larsen, 1999)
J/AJ/119/727 : M31 globular clusters photometry (Barmby+, 2000)
J/A+A/366/498 : VI photometry of M33 star clusters (Chandar+, 2001)
J/AJ/123/2490 : RV & [Fe/H] of M31 globular cluster system (Perrett+, 2002)
J/MNRAS/343/665 : VI photometry globular cluster systems (Goudfrooij+, 2003)
J/AJ/127/2674 : Globular clusters in Sculptor group (Olsen+, 2004)
J/ApJS/171/101 : Globular clusters in ACSVirgo cluster survey (Jordan+, 2007)
J/ApJS/173/538 : XUV-Disk galaxies in the Local Universe (Thilker+, 2007)
J/ApJ/681/197 : ACS Virgo Cluster Survey. XV (Peng+, 2008)
J/AJ/139/2620 : Spectroscopy of M81 globular clusters (Nantais+, 2010)
J/MNRAS/405/1293 : Compact star clusters in M81 (Santiago-Cortes+, 2010)
J/AJ/142/183 : HST photometry globulars in M81 (NGC 3031) (Nantais+, 2011)
J/ApJ/805/160 : Old star clusters in M101 from HST (Simanton+, 2015)
J/ApJ/824/71 : Compact star clusters in M51 with HST (Chandar+, 2016)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq [0/97] Internal index number
4- 12 F9.6 deg RAdeg [49.2/49.5] Right Ascension (J2000)
14- 23 F10.6 deg DEdeg [-41.3/-41] Declination (J2000)
25- 30 F6.3 mag F435Wmag [20.2/26.9] HST ACS/WFC F435W band magnitude (1)
32- 36 F5.3 mag e_F435Wmag [0.004/2] Uncertainty in F435Wmag
38- 43 F6.3 mag F555Wmag [19.5/24.2] HST ACS/WFC F555W band magnitude (1)
45- 49 F5.3 mag e_F555Wmag [0.004/0.2] Uncertainty in F555Wmag
51- 56 F6.3 mag F814Wmag [18.6/23.6] HST ACS/WFC F814W band magnitude (1)
58- 62 F5.3 mag e_F814Wmag [0.004/0.3] Uncertainty in F814Wmag
64- 68 F5.3 mag CI [2.65/3.38] Concentration index
70- 75 F6.3 pc Reff [0/16] Effective radius
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Note (1): Corrected for foreground extinction: F435Wmag=0.047mag,
F555Wmag=0.036mag, and F814Wmag=0.02mag.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 30-Sep-2022