J/A+AS/133/181 BVI imaging of 20 irregular galaxies (Makarova+ 1998)
CCD imaging of twenty nearby isolated irregular galaxies
Makarova L., Karachentsev I.D.
<Astron. Astrophys. Suppl. Ser. 133, 181 (1998)>
=1998A&AS..133..181M 1998A&AS..133..181M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Photometry, CCD
Keywords: galaxies: distances - galaxies: stellar content -
galaxies: dwarf; irregular
Abstract:
We present B, V and I CCD stellar photometry for a sample of 20 field
irregular dwarf galaxies. Their corrected radial velocity is
V0<500km/s. Most of them have been resolved into stars for the first
time. Based on photometry of their brightest blue stars we have
derived the following distances: 5.9Mpc (UGC 685), 5.4Mpc (UGC 1281),
7.2Mpc (UGC 3303), 7.0Mpc (UGC 3476), 7.3:Mpc (UGC 3600), 7.2:Mpc
(UGC 3698), 7.9Mpc (NGC 2337), 8.6Mpc (UGC 3817), 5.7Mpc (UGC 3860),
5.6Mpc (UGC 4426), ≥7.9Mpc (F 565-v1), 7.4:Mpc (UGC 5086), 7.1Mpc
(UGC 5272), 5.9Mpc (UGC 5340), 7.1Mpc (UGC 5427), 2.7:Mpc (UGC 5456),
6.6Mpc (NGC 3274), 9.3Mpc (UGC 5889), 5.2Mpc (NGC 5238), and 8.0Mpc
(UGC 9405). Our sample exhibits diverse morphological properties
evidently caused by their different starburst activity. The galaxy
sample has a median integral absolute magnitude MB=-14.6 and a
median integral colour (B-V)T=+0.47. One dwarf, UGC 5340, stands out
by its very blue colour, (B-V)T=+0.18, and by its high M(HI)/L
ratio, as expected for young galaxies. Four objects of the sample are
IRAS sources. Being well isolated systems, the considered galaxies may
be used to estimate a local value of the Hubble parameter, H=V0/D.
For half of the sample galaxies their individual H- values are
concentrated within [58-68]km/s/Mpc with a median of 65km/s/Mpc.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 24 16 *List of galaxies
tab2-8.dat 39 424 VI photometry
tab9-17.dat 39 402 BV photometry
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Note on list.dat: positions of galaxies added, from SIMBAD data-base
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See also:
J/A+AS/124/559 : VI photometry of dwarf galaxies (Karanchentsev+ 1997)
J/A+AS/128/459 : BV photometry of irregular galaxies (Makarova+ 1998)
J/A+AS/131/1 : BVI photometry of 5 CVn cloud galaxies (Karachentsev+ 1998)
J/A+AS/142/347 : BVRI photometry of NGC 6789 (Drozdovsky+, 2000)
J/A+AS/142/425 : BVRI photometry of 6 galaxies (Drozdovsky+, 2000)
Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right Ascension J2000 (hours)
4- 7 F4.1 min RAm Right Ascension J2000 (minutes)
9 A1 --- DE- Declination J2000 (sign)
10- 11 I2 deg DEd Declination J2000 (degrees)
13- 14 I2 arcmin DEm Declination J2000 (minutes)
17- 24 A8 --- Gal Galaxy name
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Byte-by-byte Description of file: tab2-8.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Gal Galaxy name
10- 12 I3 --- Star Star number
14- 17 I4 pix Xpos Rectangular coordinate of stars (1)
19- 22 I4 pix Ypos Rectangular coordinate of stars (1)
24- 28 F5.2 mag Vmag V magnitude
30- 34 F5.2 mag V-I (V-I) colour index
36- 39 F4.1 --- SHAR Sharpness parameter of stars (2)
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Note (1): The upper right corner corresponds to X=0, Y=0 of the frame
coordinates, i.e. X increases to East and Y to South.
Note (2): SHAR is a measure of the difference between the observed width of
the object and the width of the psf model.
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Byte-by-byte Description of file: tab9-17.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Gal Galaxy name
10- 12 I3 --- Star Star number
14- 17 I4 pix Xpos Rectangular coordinate of stars (1)
19- 22 I4 pix Ypos Rectangular coordinate of stars (1)
24- 28 F5.2 mag Vmag V magnitude
30- 34 F5.2 mag B-V (B-V) colour index
36- 39 F4.1 --- SHAR Sharpness parameter of stars (2)
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Note (1): The upper right corner corresponds to X=0, Y=0 of the frame
coordinates, i.e. X increases to East and Y to South.
Note (2): SHAR is a measure of the difference between the observed width of
the object and the width of the psf model.
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Acknowledgements: Sazonova Lida
(End) Patricia Bauer [CDS] 25-May-1998