J/A+A/472/121 AMIGA V. Isolation parameters (Verley+, 2007)
The AMIGA sample of isolated galaxies. V. Quantification of the isolation.
Verley S., Leon S., Verdes-Montenegro L., Combes F., Sabater J.,
Sulentic J., Bergond G., Espada D., Garcia E., Lisenfeld U., Odewhan S.C.
<Astron. Astrophys. 472, 121 (2007)>
=2007A&A...472..121V 2007A&A...472..121V
ADC_Keywords: Galaxy catalogs ; Galaxies, optical
Keywords: galaxies: general - galaxies: fundamental parameters -
galaxies: formation - galaxies: evolution
Abstract:
The AMIGA project aims to build a well defined and statistically
significant reference sample of isolated galaxies in order to estimate
the environmental effects on the formation and evolution of galaxies.
The goal of this paper is to provide a measure of the environment of
the isolated galaxies in the AMIGA sample, quantifying the influence
of the candidate neighbours identified in our previous work and their
potential effects on the evolution of the primary galaxies. Here we
provide a quantification of the isolation degree of the galaxies in
this sample.
Description:
Our starting sample is the Catalogue of Isolated Galaxies (CIG). We
used two parameters to estimate the influence exerted by the neighbour
galaxies on the CIG galaxy: the local number density of neighbour
galaxies and the tidal strength affecting the CIG galaxy. We show that
both parameters together provide a comprehensive picture of the
environment. For comparison, those parameters have also been derived
for galaxies in denser environments such as triplets, groups and
clusters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables.dat 88 1025 *Isolation parameters calculated for studied the 3
subsamples studied (tables 1-2, 4-6 of the paper)
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Note on tables.dat: Subsamples as Isolated Galaxies (CIG, Cat. VII/82),
Karachentseva triplets of galaxies (KTG, Cat. VII/83) and
Hickson Compact Groups (HCG, Cat. VII/213).
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See also:
VII/82 : Catalogue of Isolated Galaxies (Karachentseva+ 1986)
VII/83 : Isolated Triplets of galaxies (Karachentseva+ 1988)
VII/213 : Hickson's Compact groups of Galaxies (Hickson+ 1982-1994)
J/A+A/436/443 : AMIGA I. CIG recession velocities (Verdes-Montenegro+, 2005)
J/A+A/449/937 : AMIGA II. Morphological refinement (Sulentic+, 2006)
J/A+A/462/507 : AMIGA III. IRAS data (Lisenfeld+, 2007)
J/A+A/470/505 : AMIGA IV. Neighbours around CIG galaxies (Verley+, 2007)
J/A+A/485/475 : AMIGA VI. GIG galaxies radio continuum properties (Leon+ 2008)
J/A+A/486/73 : AMIGA VII. FIR and radio study (Sabater+, 2008)
J/A+A/532/A117 : AMIGA VIII. Flux ratio asymmetry parameter (Espada+, 2011)
http://www.iaa.es/AMIGA.html : AMIGA HomePage
Byte-by-byte Description of file: tables.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Galaxy name
11- 20 F10.6 deg RAdeg Right ascension in decimal degrees (J2000)
22- 31 F10.6 deg DEdeg Declination in decimal degrees (J2000)
34- 37 F4.2 arcmin Amaj ? Major axis (1)
40 A1 --- l_Vel Limit flag on Vel
41- 45 I5 km/s Vel ? Recession velocity (1)
47- 53 F7.3 --- etak ?=-99 Local number density of similar size
neighbours (2)
55- 57 I3 --- k [2,5]?=-99 Number of similar size neighbours
taken into account to calculate etak (2)
59- 64 F6.3 --- Q Tidal strength estimation in the whole
available square field
66- 72 F7.3 --- Qkat ?=-98.000 Tidal strength estimation of similar
size neighbours in the whole available
square field (3)
74- 80 F7.3 --- Q0.5 ?=-98 Tidal strength estimation
within 0.5Mpc (3)
82- 88 F7.3 --- Q0.5,kat ?=-98 Tidal strength estimation of similar
size neighbours within 0.5Mpc (3)
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Note (1): Data only for KTG and HCG galaxies.
Note (2): defined as log((k-1)/V(r'k)) where V(r'k)=4πr'3/3 is the
apparent volume (r'k in arcmin) to the kth nearest neighbour,
and k=5 or less if there are not enough neighbours in the field.
The isolation is therefore larger for larger values of etak.
Special values are etak=-99.000 and k=-99 when there are not,
at least, two similar size neighbours.
Note (3): Q is defined as the ratio between the tidal and binding forces,
in a log scale: greater values mean less isolated galaxy.
A value of 0 indicates that the internal forces have the same
amplitude as the sum of the tidal forces affecting the primary
galaxy. Values set to -98.000 for galaxies with unknown redshifts.
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Acknowledgements:
Simon Verley, simon(at)arcetri.astro.it
References:
Leon et al., Paper I 2003A&A...411..391L 2003A&A...411..391L, Cat. J/A+A/411/391
Sulentic et al., Paper II 2006A&A...449..937S 2006A&A...449..937S Cat. J/A+A/449/937
Lisenfeld et al., Paper III 2007A&A...462..507L 2007A&A...462..507L, Cat. J/A+A/462/507
Verley et al., Paper IV 2007A&A...470..505V 2007A&A...470..505V, Cat. J/A+A/470/505
Leon et al., Paper VI 2008A&A...485..475L 2008A&A...485..475L, Cat. J/A+A/485/475
Sabater et al., Paper VII 2008A&A...486...73S 2008A&A...486...73S, Cat. J/A+A/486/73
Espada et al., Paper VIII 2011A&A...532A.117E 2011A&A...532A.117E, Cat. J/A+A/532/A117
Lisenfeld et al., Paper IX 2011A&A...534A.102L 2011A&A...534A.102L, Cat. J/A+A/534/A102
Fernandez Lorenzo et al., Paper X 2012A&A...540A..47F 2012A&A...540A..47F, Cat. J/A+A/540/A47
(End) Patricia Vannier [CDS] 20-Aug-2007