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. =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: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- 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) -------------------------------------------------------------------------------- Note on tables.dat: Subsamples as Isolated Galaxies (CIG, Cat. ), Karachentseva triplets of galaxies (KTG, Cat. ) and Hickson Compact Groups (HCG, Cat. ). -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 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 eta_k_ (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) -------------------------------------------------------------------------------- Note (1): Data only for KTG and HCG galaxies. Note (2): defined as log((k-1)/V(r'k)) where V(r'k)=4{pi}r'^3^/3 is the apparent volume (r'k in arcmin) to the k^th^ 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. -------------------------------------------------------------------------------- Acknowledgements: Simon Verley, simon(at)arcetri.astro.it References: Leon et al., Paper I 2003A&A...411..391L, Cat. J/A+A/411/391 Sulentic et al., Paper II 2006A&A...449..937S Cat. J/A+A/449/937 Lisenfeld et al., Paper III 2007A&A...462..507L, Cat. J/A+A/462/507 Verley et al., Paper IV 2007A&A...470..505V, Cat. J/A+A/470/505 Leon et al., Paper VI 2008A&A...485..475L, Cat. J/A+A/485/475 Sabater et al., Paper VII 2008A&A...486...73S, Cat. J/A+A/486/73 Espada et al., Paper VIII 2011A&A...532A.117E, Cat. J/A+A/532/A117 Lisenfeld et al., Paper IX 2011A&A...534A.102L, Cat. J/A+A/534/A102 Fernandez Lorenzo et al., Paper X 2012A&A...540A..47F, Cat. J/A+A/540/A47 ================================================================================ (End) Patricia Vannier [CDS] 20-Aug-2007