VII/204 Galaxy properties at NGP (Odewahn+ 1995)
Galaxy properties at the North Galactic Pole.
I. Photometric properties on large spatial scales.
Odewahn S.C., Aldering G.
<Astron. J. 110, 2009 (1995)>
=1995AJ....110.2009O 1995AJ....110.2009O (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; Magnitudes
Abstract:
A two-color study of the galaxies detected on POSS-I in a 289deg2
region centered on the North Galactic Pole is presented. We use a
variety of mapping techniques to characterize the large-scale spatial
distribution of galaxies. The depth and sample size of this new survey
allows, for the first time, the isolation of large photometric
subsamples of galaxies in high- and low-density environments on the
scale of superclusters. Our principal finding is a statistically
significant difference between the mean photometric properties of
these subsamples in the sense that galaxies in the high-density Coma
and filament environments have redded colors and larger concentration
indices than galaxies drawn from low-density interfilament regions.
These results are in agreement with the known morphology-density
relation.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 58 36402 All APS-measured galaxies with Omag ≤ 20.0
(NGP9)
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Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 7 I7 --- No Object number (unique within a plate)
9- 11 I3 --- POSS-I POSS-I plate number (see catalog VI/25)
13- 14 I2 h RAh Right ascension (1950)
16- 17 I2 min RAm Right ascension (1950)
19- 23 F5.2 s RAs Right ascension (1950)
25 A1 --- DE- Declination sign
26- 27 I2 deg DEd Declination (1950)
29- 30 I2 arcmin DEm Declination (1950)
32- 35 F4.1 arcsec DEs [0/60] Declination (1950)
37- 41 F5.2 mag Omag O isophotal magnitude (threshold about
24.5 mag/arcsec2 in B)
43- 47 F5.2 mag O-E O-E color
49- 52 F4.2 --- C31 *C31 concentration index
54- 58 F5.1 arcsec Diam Isophotal (equivalent) diameter
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Note on C31: this index is the ratio between the radius
with 75% and 25% of the isophotal light.
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History: Copied on 18-Nov-1996 from
http://groucho.la.asu.edu/~sco/sco1/data/data.html
(End) Francois Ochsenbein [CDS] 18-Nov-1996