J/A+A/564/A94 CIG sample 3-dimensional environment (Argudo-Fernandez+, 2014) ================================================================================ Effects of the environment on galaxies in the Catalogue of Isolated Galaxies: physical satellites and large scale structure. Argudo-Fernandez M., Verley S., Bergond G., Sulentic J., Sabater J., Fernandez Lorenzo M., Espada D., Leon S., Sanchez-Exposito S., Santander-Vela J. D., Verdes-Montenegro L. =2014A&A...564A..94A (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Galaxies, photometry ; Spectroscopy Keywords: galaxies: evolution - galaxies: formation - galaxies: general Abstract: We present a study of the 3-dimensional environment for a sample of 386 galaxies in the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973) using the Ninth Data Release of the Sloan Digital Sky Survey (SDSS-DR9). We aim to identify and quantify the effects of the satellite distribution around a sample of galaxies in the CIG, as well as the effects of the Large Scale Structure (LSS). To recover the physically bound galaxies we first focus on the satellites which are within the escape speed of each CIG galaxy. We also propose a more conservative method using the stacked Gaussian distribution of the velocity difference of the neighbours. The tidal strengths affecting the primary galaxy are estimated to quantify the effects of the local and LSS environments. We also define the projected number density parameter at the fifth nearest neighbour to characterise the LSS around the CIG galaxies. Out of the 386 CIG galaxies considered in this study, at least 340 (88% of the sample) have no physically linked satellite. Following the more conservative Gaussian distribution of physical satellites around the CIG galaxies leads to upper limits. Out of the 386 CIG galaxies, 327 (85% of the sample) have no physical companion within a projected distance of 0.3Mpc. The CIG galaxies are distributed following the LSS of the local Universe, although presenting a large heterogeneity in their degree of connection with it. When present around a CIG galaxy, the effect of physically bound galaxies largely dominates (usually by more than 90%) the tidal strengths generated by the LSS. The CIG samples a variety of environments, from galaxies with physical satellites to galaxies with no neighbours within 3Mpc. A clear segregation appears between early-type CIG galaxies with companions and isolated late-type CIG galaxies. Isolated galaxies are in general bluer, with likely younger stellar populations and rather high star formation with respect to older, redder CIG galaxies with companions. Reciprocally, the satellites are redder and with an older stellar populations around massive early-type CIG galaxies, while they have a younger stellar content around massive late-type CIG galaxies. This suggests that the CIG is composed of a heterogeneous population of galaxies, sampling from old to more recent, dynamical systems of galaxies. CIG galaxies with companions might have a mild tendency (0.3-0.4dex) to be more massive, and may indicate a higher frequency of having suffered a merger in the past. Description: Quantification of the local and large scale environments for 386 CIG galaxies using 3-dimensional data from the Ninth Data Release of the Sloan Digital Sky Survey. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 47 386 Quantification of the local and large scale environments for 386 CIG galaxies using 3-dimensional data from the SDSS-DR9 -------------------------------------------------------------------------------- See also: J/A+A/411/391 : AMIGA project. CIG galaxies revised positions (Leon+ 2003) J/A+A/436/443 : AMIGA I. Velocities of CIG galaxies (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/472/121 : AMIGA V. Isolation parameters (Verley+, 2007) J/A+A/485/475 : AMIGA VI. Radio fluxes of the isolated galaxies (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) J/A+A/534/A102 : AMIGA IX. Molecular gas properties (Lisenfeld+, 2011) J/A+A/540/A47 : AMIGA X. Isolated galaxy colors (Fernandez Lorenzo+, 2012) J/A+A/545/A15 : AMIGA XI. Optical nuclear activity (Sabater+, 2012) J/A+A/560/A9 : AMIGA XII. Revision of the isolation degree (Argudo-Fernandez+, 2013) J/MNRAS/434/325 : 452 AMIGA galaxies physical parameters (Fernandez Lorenzo+, 2013) http://amiga.iaa.es : AMIGA Home Page Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 I5 --- CIG CIG (VII/82) number, in Simbad 7- 11 F5.2 --- Qsat ?=- Tidal strength estimation for satellites using the escape speed method 13- 17 F5.2 --- QsatS ?=- Tidal strength estimation for satellites using the Gaussian distribution method 19 I1 --- ksat Number of satellites selected following the escape speed method 21 I1 --- ksatS Number of satellites selected following the Gaussian distribution method 23- 27 F5.2 --- QLSS ?=- Tidal strength estimation of the LSS 29- 34 F6.2 --- rhoLSS ?=- Local number density estimation of the LSS 36- 37 I2 --- kLSS Number of LSS associations 39- 42 F4.2 --- Qsat/QLSS ?=- Relation between Qsat and QLSS, from 0 to 1 if the considered satellites amount from 0% to 100% to the total tidal strength 44- 47 F4.2 --- QsatS/QLSS ?=- Relation between Qsat,sup and QLSS, from 0 to 1 if the considered satellites amount from 0% to 100% to the total tidal strength -------------------------------------------------------------------------------- Acknowledgements: Maria del Carmen Argudo Fernandez, margudo(at)iaa.es ================================================================================ (End) Patricia Vannier [CDS] 24-Feb-2014