J/AJ/127/660 Photometry in southern tail of the Antennae (Saviane+, 2004)
The stellar content of the southern tail of NGC 4038/4039 and a revised distance
Saviane I., Hibbard J.E., Rich R.M.
<Astron. J., 127, 660-678 (2004)>
=2004AJ....127..660S 2004AJ....127..660S
ADC_Keywords: Galaxies, photometry ; Associations, stellar ; Photometry, VRI
Keywords: galaxies: distances and redshifts -
galaxies: individual: NGC 4038, NGC 4039 - galaxies: interactions -
galaxies: peculiar - galaxies: stellar content
Abstract:
We have used the Hubble Space Telescope and Wide Field Planetary
Camera 2 to image the putative tidal dwarf galaxy located at the tip
of the Southern tidal tail of NGC 4038/4039, the Antennae. We resolve
individual stars and identify two stellar populations. Hundreds of
massive stars are present, concentrated into tight OB associations on
scales of 200pc, with ages ranging from 2 to 100Myr. An older stellar
population is distributed roughly following the outer contours of the
neutral hydrogen in the tidal tail; we associate these stars with
material ejected from the outer disks of the two spirals. The older
stellar population has a red giant branch tip at I=26.5±0.2 from
which we derive a distance modulus (m-M)0=30.7±0.25. The implied
distance of 13.8±1.7Mpc is significantly smaller than commonly
quoted distances for NGC 4038/4039. In contrast to the previously
studied core of the merger, we find no superstar clusters (SSCs).
Description:
The field centered at
(RA, DE, epoch) = (12 01 25.6, -19 00 31.9; J2000.0)
was imaged on 1998 November 23 and 24 and 1999 January 4 and 5.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 72 4093 Photometry of individual stars
table2.dat 68 8 Photometric properties of the eight associations
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See also:
J/AJ/109/960 : Young star clusters in The Antennae (Whitmore+ 1995)
J/ApJ/561/727 : BVI photometry in the Antennae galaxies (Zhang+, 2001)
J/ApJ/599/1049 : Supergiant molecular complexes in the Antennae (Wilson+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- [SHR2004] Stellar identification number,
[SHR2004] Star NNN in Simbad
6- 7 I2 h RAh Hour of right ascension (J2000)
9- 10 I2 min RAm Minute of right ascension (J2000)
12- 17 F6.3 s RAs Second of right ascension (J2000)
19 A1 --- DE- Sign of the declination (J2000)
20- 21 I2 deg DEd Degree of declination (J2000)
23- 24 I2 arcmin DEm Arcminute of declination (J2000)
26- 30 F5.2 arcsec DEs Arcsecond of declination (J2000)
32- 37 F6.3 mag Vmag True Johnson V-band magnitude
39- 44 F6.3 mag F555Wmag True HST F555W-band magnitude
46- 50 F5.3 mag e_F555Wmag Photometric error in F555Wmag
52- 57 F6.3 mag V-Ic The Johnson V-I (Cousins) color
59- 64 F6.3 mag F555W-F814W HST F555W-F814W color
66- 70 F5.3 mag e_F555W-F814W Photometric error in F555W-F814W
72 I1 --- Chip The WFPC2 chip identification number
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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 I1 --- [SHR2004] Sequential number of the region,
[SHR2004] Assoc N in Simbad
3- 5 A3 --- [MLD92] Mirabel et al. (1992A&A...256L..19M 1992A&A...256L..19M) designation
8- 9 I2 h RAh Right ascension (J2000.0)
11- 12 I2 min RAm Right ascension (J2000.0)
14- 18 F5.2 s RAs Right ascension (J2000.0)
20 A1 --- DE- Declination sign (J2000.0)
21- 22 I2 deg DEd Declination (J2000.0)
24- 25 I2 arcmin DEm Declination (J2000.0)
27- 31 F5.2 arcsec DEs Declination (J2000.0)
33- 34 I2 --- NBlue Number of blue stars ((V-I)0≤0.5)
36- 37 I2 --- NTot Total number of stars
39- 42 F4.1 mag IcMAGB Absolute Cousins I magnitude for blue stars (1)
44- 47 F4.1 mag VMAGB Absolute V magnitude for blue stars (1)
49- 52 F4.1 mag (V-Ic)0B Dereddened V-I Cousins colour for blue stars
54- 58 F5.1 mag IcMAGT Absolute Cousins I magnitude for all stars (1)
60- 64 F5.1 mag VMAGT Absolute V magnitude for all stars (1)
66- 68 F3.1 mag (V-Ic)0T Dereddened V-I Cousins colour for all stars
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Note (1): The absolute magnitudes have been computed assuming the
Whitmore et al. (1999AJ....118.1551W 1999AJ....118.1551W) distance modulus (m-M)0=31.4.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 02-Jul-2004