J/ApJS/195/15 Luminosity profiles of BCGs (Donzelli+, 2011)
The luminosity profiles of brightest cluster galaxies.
Donzelli C.J., Muriel H., Madrid J.P.
<Astrophys. J. Suppl. Ser., 195, 15 (2011)>
=2011ApJS..195...15D 2011ApJS..195...15D
ADC_Keywords: Clusters, galaxy ; Magnitudes, absolute ; Galaxies, photometry
Keywords: galaxies: clusters: general -
galaxies: elliptical and lenticular, cD - galaxies: interactions
Abstract:
We have derived detailed R-band luminosity profiles and structural
parameters for a total of 430 brightest cluster galaxies (BCGs), down
to a limiting surface brightness of 24.5mag/arcsec2. Light profiles
were initially fitted with a Sersic's R1/n model, but we found that
205 (∼48%) BCGs require a double component model to accurately match
their light profiles. The best fit for these 205 galaxies is an inner
Sersic model, with indices n∼1-7, plus an outer exponential component.
Thus, we establish the existence of two categories of the BCG
luminosity profiles: single and double component profiles. We found
that double profile BCGs are brighter (∼0.2mag) than single profile
BCGs. From a subsample of 24 BCGs, we found strong evidence that
extra-light at intermediate radii in double profile BCGs is related to
the presence of a faint stellar envelope. Similarly, from another
subsample of 12 BCGs we also found that extra-light is related to star
formation.
Description:
BCG images used in this work were provided by M. Postman (STScI) who
kindly gave us access to the raw data. They were obtained under
photometric conditions using the KPNO 2.1m and 4m telescopes, and the
CTIO 1.5m telescope between 1989 November and 1995 April over a total
of 13 observing runs. All the images were acquired in the Kron-Cousins
Rc band and have typically exposure times of 200-600s.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 97 430 BCGs photometrical parameters
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See also:
VII/165 : Measured Redshifts of Abell Clusters of Galaxies (Andernach 1991)
VII/87 : Data on 1889 Abell's clusters of galaxies (Leir+ 1977)
J/AJ/125/478 : HST imaging of brightest cluster galaxies (Laine+, 2003)
J/ApJ/440/28 : Brightest Cluster Galaxies velocities (Postman+ 1995)
J/ApJ/425/418 : Absoulue R mag of brightest clusters galaxies (Lauer+, 1994)
J/ApJ/241/486 : Absolute magnitudes in 116 nearby Abell clusters (Hoessel+,
1980)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Abell cluster name (ANNNN)
7- 11 F5.2 mag/arcsec2 mue Effective surface magnitude (in Rc band)
13- 18 F6.2 kpc re Effective radius (in Rc band)
20- 23 F4.2 --- n Sersic n parameter
25- 29 F5.2 mag/arcsec2 mu0 ? Central Rc surface magnitude
31- 35 F5.2 kpc r0 ? Scale length
37- 42 F6.2 mag MAGS Absolute magnitude of the Sersic component
44- 49 F6.2 mag MAGexp ?=0 Absolute Rc magnitude of the exponential
component
51- 56 F6.2 mag MAGtot Total Rc absolute magnitude of the BCG
58- 62 F5.2 --- S/e ? Sersic to exponential component light ratio
64- 67 F4.2 --- alpha The α parameter (1)
69- 72 F4.2 --- elli Inner ellipticity (2)
74- 77 F4.2 --- ello Outer ellipticity (2)
79- 83 F5.1 --- PAi Inner position angle of the isophote (2)
85- 90 F6.1 --- PAo Outer position angle of the isophote (2)
92- 97 F6.2 mag MAGM Metric absolute magnitude, calculated at
r=14.5kpc
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Note (1): The logarithmic slope of the metric luminosity or α parameter
which is defined as:
α=d(log(Lm))/d(log(rm)),
where Lm is the total BCG luminosity within a circular aperture of
radius rm centered on the BCG nucleus. Following Postman & Lauer
(1995, Cat. J/ApJ/440/28) we have calculated this parameter at r=14.5kpc.
Note (2): The inner ellipticity (measured at 10"), outer ellipticity
(measured at ∼23-24mag/arcsec2), and inner and outer position angles
of the isophotes where the ellipticities are measured. Position angles
are from north to east and the typical observed errors are ∼5°,
while typical errors for ellipticities are 0.06.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 19-Sep-2011