J/A+A/485/475 AMIGA. VI. Radio fluxes of the isolated galaxies (Leon+ 2008) ================================================================================ The AMIGA sample of isolated galaxies. VI. Radio continuum properties of isolated galaxies: a very radio quiet sample. Leon S., Verdes-Montenegro L., Sabater J., Espada D., Lisenfeld U., Ballu A., Verley S., Bergond G., Garcia E. =2008A&A...485..475L ================================================================================ ADC_Keywords: Surveys ; Galaxies, radio Keywords: galaxies: evolution - galaxies: luminosity function - radio continuum: galaxies - surveys - mass function Abstract: This paper is part of a series that describes the results of the AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies) project, studying the largest sample of very isolated galaxies in the local Universe. The study of the radio properties of the AMIGA sample is intended to characterize the radio continuum emission for a sample least affected by the local environment, thus providing a reference against which less isolated and interacting samples can be compared. Radio continuum data at 325, 1420, and 4850MHz were extracted from the WENSS, NVSS/FIRST, and GB6 surveys, respectively. The source extractions have been obtained from reprocessing the data and new detections added to the cross- matched detections with the respective survey catalogs. We focus on the complete AMIGA subsample composed of 719 galaxies. A catalog of radio fluxes was obtained from the above four surveys. Comparison between the NVSS and FIRST detections indicates that the radio continuum is coming from disk-dominated emission in spiral galaxies, in contrast to the results found in high-density environments where nuclear activity is more frequent. The comparison of the radio continuum power with a comparable sample, which is however not selected with respect to its environment, the Condon et al. UGC-SF sample of star-forming field galaxies, shows a lower mean value for the AMIGA sample. We have obtained radio-to-optical flux ratios (R) using the NVSS radio continuum flux. The distribution of R for the AMIGA galaxies is consistent with a sample dominated by radio emission from star formation (SF) and a small number of active galactic nuclei (AGN), with less than 3% of the sample with R>100. We derived the radio luminosity function (RLF) and total power density of the radio continuum emission for the AMIGA sample at 1.4GHz, and compared them with results from other low-redshift studies. The Schechter fit of the RLF indicates a major weight of the low-luminosity galaxies. The results indicate the very low level of radio continuum emission in our sample of isolated galaxies, which is dominated by mild disk SF. It confirms thus the AMIGA sample as a suitable template to effectively quantify the role of interactions in samples extracted from denser environments. Description: Table 2 gives the radio flux density and radio power at 325/352MHz (from the WENSS survey), 1420MHz (from the NVSS survey) and 4850MHz (from GB6 survey) for the whole original Catalog of Isolated Galaxies (CIG, Karachentseva, 1973, ), including 1050 galaxies. Note that object #781 is a globular cluster (Pal 15) and should not be considered. The codes for the origin of data are as follows: 0 stands for no data, 1 if included in the original catalog (WENSS , NVSS , or GB6 ), 2 if determined from this work and 3 if extracted from NED. Reference code 4 indicates FIRST () detection without a corresponding NVSS detection. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table2.dat 76 1050 Radio-continuum parameters of 1050 CIG galaxies -------------------------------------------------------------------------------- See also: VII/82 : Catalogue of Isolated Galaxies (Karachentseva+ 1986) VIII/40 : GB6 catalog of radio sources (Gregory+ 1996) VIII/62 : The Westerbork Northern Sky Survey (Leiden, 1998) VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998) VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003) J/A+A/436/443 : AMIGA I. 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/472/121 : AMIGA V. Isolation parameters (Verley+, 2007) 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: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 4 I4 --- CIG CIG number (Cat. VII/82) K73 NNNN in Simbad 6 A1 --- l_F325 [<] upper limit on 352MHz flux (1) 7- 12 F6.2 mJy F325 ?=0.00 Flux at 325 or 352MHz (1) 14- 18 F5.2 mJy e_F325 ?=0.00 Error on the flux at 325/352MHz 20 A1 --- l_P325 [<] upper limit on 352MHz power (1) 21- 26 F6.3 [W/Hz] P325 ?=0.000 Radio power at 325/352MHz 28 I1 --- r_F325 [0/2] Code for data at 325MHz (2) 30 A1 --- l_F1420 [<] upper limit on 1420MHz flux (1) 31- 36 F6.2 mJy F1420 ?=0.00 Flux at 1420MHz 38- 42 F5.2 mJy e_F1420 ?=0.00 Error on the flux at 1420MHz 44 A1 --- l_P1420 [<] upper limit on 352MHz power (1) 45- 50 F6.3 [W/Hz] P1420 ?=0.000 Radio power at 1420MHz 52 I1 --- r_F1420 [1/3] Code for data at 1420MHz (2) 54 A1 --- l_F4850 [<] upper limit on 4850MHz flux (1) 55- 60 F6.2 mJy F4850 ?=0.00 Flux at 4850MHz 62- 66 F5.2 mJy e_F4850 ?=0.00 Error on the flux at 4850MHz 68 A1 --- l_P4850 [<] upper limit on 4850MHz power (1) 69- 74 F6.3 [W/Hz] P4850 ?=0.000 Radio power at 4850MHz 76 I1 --- r_F4850 [0/2] Code for data at 4850MHz (2) -------------------------------------------------------------------------------- Note (1): The original table used negative values for upper limits. Note (2): Codes for the origin of the data are as follows: 0 = no data 1 = original catalog values (WENSS (325MHz, Cat. VIII/62), NVSS (1420MHz, Cat. VIII/65) or GB6 (4850MHz, Cat. VIII/40) 2 = this work 3 = from NED 4 = FIRST detection without NVSS counterpart -------------------------------------------------------------------------------- Acknowledgements: Jose Sabater Montes, jsm(at)iaa.es Stephane Leon, leon(at)iram.es History: * 21-Apr-2008: Original version * 07-Aug-2008: Replaced negative values by the '<' limit sign. 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 Verley et al., Paper V 2007A&A...472..121V, Cat. J/A+A/472/121 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) Stephane Leon [IRAM, Spain], Patricia Vannier [CDS] 21-Apr-2008