J/AJ/110/1959 VLA survey of Abell clusters. V. (Ledlow+ 1995)
A 20cm VLA survey of Abell clusters of galaxies. V.
Optical observations and surface photometry
Ledlow M.J., Owen F.N.
<Astron. J. 110, 1959 (1995)>
=1995AJ....110.1959L 1995AJ....110.1959L
ADC_Keywords: Clusters, galaxy ; Photometry, surface
Abstract:
We present results from a program of optical imaging of 265 radio
galaxies in rich clusters. Using isophotal surface photometry, we
investigate the optical properties such as the morphology,
surface-brightness profiles, surface-brightness/size relationships,
ellipticities, and the frequency of nonelliptical isophotes. The
results are compared to a "normal" nonradio-selected sample of
elliptical galaxies from the same clusters. The goal is to determine
if the parent population of FR I radio galaxies can be distinguished
optically from radio-quiet galaxies. The results of the analysis are
that cluster ellipticals are a very homogeneous class of objects. The
optical properties are consistent with a one-parameter family, where
the optical luminosity is the fundamental parameter. In all tests
considered, radio-loud FR I galaxies cannot be distinguished optically
from radio-quiet galaxies selected from the same environment. The
local density of nearby companions (<20kpc) and the frequency of
morphological peculiarities or tidal interactions are not
statistically different between the radio-loud and quiet samples.
There is some suggestion from comparison to published samples of
non-cluster radio galaxies, that the cluster environment is not
condusive to long-lived tidal interactions, and that such events may
be more important to galaxy evolution in poor groups and lower density
environments. Such events appear to have little influence on the
formation of FR I radio galaxies in rich clusters. The results are
consistent with the idea that all elliptical galaxies may at some time
(or many times) contain powerful (FR I) radio sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 100 186 Results of surface photometry for z<0.09 sample
table3.dat 100 77 Results of surface photometry for 0.09<z<0.20
sample
table2.tex 133 209 AASTeX version of table2.dat
table3.tex 138 100 AASTeX version of table3.dat
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Byte-by-byte Description of file: table2.dat table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Abell Abell number
6- 14 A9 --- IAU IAU name in B1950 coordinates
16- 20 F5.2 mag VmagGO m(GO) the apparent Gunn-Oke magnitude (1)
22- 26 F5.2 mag VmagS []? m(S) the apparent Sandage magnitude (2)
28- 32 F5.2 mag mag24.5 m(24.5) the apparent isophotal magnitude (3)
33 A1 --- n_mag24.5 [E ] ma_24.5 is an estimated value (4)
35- 40 F6.2 mag VMAGGO M(GO) absolute Gunn-Oke aperture mag.
42- 47 F6.2 mag VMAGS []? M(S) absolute Sandage aperture mag.
49- 54 F6.2 mag MAG24.5 M_24.5 absolute isophotal magnitude
55 A1 --- n_MAG24.5 [E ] M_24.5 is an estimated value (4)
57- 61 F5.2 kpc r24.5 []? Radius, 24.5 mag/arcsec2 isophote (5)
63- 67 F5.2 kpc re []? de Vaucouleurs effective radius
69- 73 F5.3 --- eps []? Ellipticity, 24.5 mag/arcsec2 isophote
75- 77 I3 deg PA []? Pos. angle, 24.5 mag/arcsec2 isophote
79- 84 F6.4 --- sig_pl []? Std dev from power-law fit to profile (6)
86- 91 F6.4 --- sig_r []? Std dev from r(1/4)-law fit to profile (7)
93- 97 F5.2 --- plexp []? Best-fitting power-law exponent (8)
98 A1 --- l_N [< ] Limiting character for N
99-100 I2 --- N []? Number of points used in profile fitting (9)
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Note (1): m(GO) the apparent Gunn-Oke magnitude (13.1kpc radius for H=75)
Note (2): m(S) the apparent Sandage magnitude (29.1kpc radius for H=75)
Note (3): m(24.5) the apparent isophotal magnitude measured to 24.5mag/arcsec2
in the rest-frame of the galaxy
Note (4): An E appears if the isophotal magnitude value was estimated from
figure 1 in this paper from the relationship between M(GO) and
M(24.5). In this case, no surface-brightness profile was fit to the
image. This occurred when a nearby galaxy or multiple nucleus was
too difficult to remove.
Note (5): r(24.5) the radius in kpc measured at the 24.5mag/arcsec2 isophote
(note that r=sqrt(ab) was used from the elliptical isophotal fits)
Note (6): sigma(pl) the standard deviation from a power-law least-squares fit
to the surface-brightness profile
Note (7): sigma(r1/4) the standard deviation from a r(1/4)-law least-squares
fit to the surface-brightness profile
Note (8): The best-fitting power-law exponent to the surface-brightness profile
Note (9): The number of points used in the surface-brightness profile fitting
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Origin: AAS CD-ROM series, Volume 5, 1995 Lee Brotzman [ADS] 02-Nov-1995
Historical Note:
* table2.dat : the extra '6' following mag24.5 value for row #139
was changed to a blank;
* table3.dat : the extra 'f' preceding VmagGO in row #62, byte#15
was changed to a blank;
(End) [CDS] 26-Jan-1996