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J/A+A/604/A43       HI in nearby radio sources               (Maccagni+, 2017)

Kinematics and physical conditions of H I in nearby radio sources. The last survey of the old Westerbork Synthesis Radio Telescope. Maccagni F.M., Morganti R., Oosterloo T.A., Gereb K., Maddox N. <Astron. Astrophys., 604, A43 (2017)> =2017A&A...604A..43M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, radio ; Galaxies, nearby ; H I data Keywords: radio lines: ISM - radio lines: galaxies - galaxies: nuclei - galaxies: ISM - infrared: ISM Abstract: We present an analysis of the properties of neutral hydrogen (HI) in 248 nearby (0.02<z<0.25) radio galaxies with S1.4GHz>30mJy and for which optical spectroscopy is available. The observations were carried out with the Westerbork Synthesis Radio Telescope as the last large project before the upgrade of the telescope with phased array feed receivers (Apertif). The sample covers almost four orders of magnitude in radio power from logP1.4GHz=22.5W/Hz and 26.2W/Hz. We detect HI in absorption in 27%±5.5% of the objects. The detections are found over the full range of radio power. However, the distribution and kinematics of the absorbing HI gas appear to depend on radio power, the properties of the radio continuum emission, and the dust content of the sources. Among the sources where HI is detected, gas with kinematics deviating from regular rotation is more likely found as the radio power increases.In the great majority of these cases, the HI profile is asymmetric with a significant blue-shifted component. This is particularly common for sources with logP1.4GHz>24W/Hz, where the radio emission is small, possibly because these radio sources are young. The same is found for sources that are bright in the mid-infrared, i.e. sources rich in heated dust.In these sources, the HI is outflowing likely under the effect of the interaction with the radio emission. Conversely, in dust-poor galaxies, and in sources with extended radio emission, at all radio powers we only detect HI distributed in a rotating disk. Stacking experiments show that in sources for which we do not detect HI in absorption directly, the HI has a column density that is lower than 3.5x1017(Tspin/cf)cm-2. We use our results to predict the number and type of HI absorption lines that will be detected by the upcoming surveys of the Square Kilometre Array precursors and pathfinders (Apertif, MeerKAT, and ASKAP). Description: We expand the sample of radio sources presented in Gereb et al. (2014A&A...569A..35G, hereafter G14) and Gereb et al. (2015, Cat. J/A+A/575/A44, hereafter G15) to lower radio fluxes and radio powers. As in those studies, we selected the sources by cross-correlating the seventh data release of the Sloan Digital Sky Survey catalogue (SDSS DR7; York et al. 2000AJ....120.1579Y) with the Faint Images of the Radio Sky at Twenty-cm catalogue (FIRST; Becker et al. 1995ApJ...450..559B, See Cat. VIII/92). The sources lie above declination DE>10° and between 07h51m00s and 17h22m25s in right ascension. The sources are restricted to the redshift range 0.02<z<0.25, which is the redshift interval covered by the WSRT observing band, 1150-1400MHz. The sample of G14 and G15 was limited to sources brighter than 50mJy and consists of 101 sources. In the present study, we selected all sources that have radio core flux density 30mJy<S1.4GHz<50mJy. This includes 219 sources, of which 183 were successfully observed before the telescope was switched off for the upgrade of the receivers. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablea1.dat 114 242 *Table of sources
Note on tablea1.dat: Erroneous Rtype corrected in agreement with the author Filippo Maccagni
See also: J/A+A/575/A44 : HI absorption in flux-selected radio AGNs (Gereb+, 2015) Byte-by-byte Description of file: tablea1.dat
Bytes Format Units Label Explanations
1- 19 A19 --- Source Source name ( 20 A1 --- n_Source [*] Note on Source (1) 22- 27 F6.4 --- zopt Optical redshift measured from the SDSS spectrum 30- 36 F7.2 mJy S1.4GHz Flux density at 1.4GHz 38- 42 F5.2 W/Hz P1.4GHz Radio power at 1.4GHz 44 A1 --- RType [CEI] Radio type (2) 46- 50 A5 --- WType WISE type (3) 52 A1 --- l_Noise Limit flag on Noise 53- 57 F5.2 mJy Noise 3σ detection limit of the HI spectrum 61- 66 F6.4 --- tauPeak ?=- Peak optical depth of the HI detection 68- 72 F5.2 km/s Inttaudv ?=- Integrated optical depth of the HI line 74- 79 F6.2 km/s FWHM ?=- Full width at half maximum 81- 85 F5.2 km/s e_FWHM ?=- rms uncertainty on FWHM 88- 93 F6.2 km/s FW20 ?=- Full width at 20% of the peak flux 95- 99 F5.2 km/s e_FW20 ?=- rms uncertainty on FW20 101-107 F7.2 km/s Cent ?=- Position of the centroid of the line 109-114 F6.2 km/s e_Cent ?=- rms uncertainty on Cent
Note (1): Galaxies denoted by (*) have been presented in Gereb et al. (2014A&A...569A..35G), and Gereb et al. (2015, Cat. J/A+A/575/A44. Note (2): Radio classification as follows: C = compact source E = extended source I = interacting source Note (3): WISE colour-colour classification (see Sect. 2.2) as follows: dp = dust poor galaxy 12um = 12um bright galaxy 4.6um = 4.6um bright galaxy
History: * From electronic version of the journal. Erroneous Rtype corrected in agreement with the author Filippo Maccagni.
(End) Patricia Vannier [CDS] 23-Oct-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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