J/MNRAS/465/997 Low-luminosity radio-loud AGN (Chandola+, 2017)
H I absorption towards low-luminosity radio-loud active galactic nuclei of
different accretion modes and WISE colours.
Chandola Y., Saikia D.J.
<Mon. Not. R. Astron. Soc., 465, 997-1007 (2017)>
=2017MNRAS.465..997C 2017MNRAS.465..997C (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Spectroscopy ; Photometry, infrared
Keywords: galaxies: active - galaxies: general - galaxies: nuclei -
infrared: galaxies - radio continuum: galaxies - radio lines: galaxies
Abstract:
HI absorption studies of active galaxies enable us to probe their
circumnuclear regions and the general interstellar medium and study
the supply of gas that may trigger nuclear activity. In this article,
we investigate the dependence of the detection rate of HI absorption
on the nature of radio galaxies based on their emission-line spectra
and on the nature of host galaxies based on WISE colours and their
radio structure, which may help us understand the different accretion
modes. We find significant differences in the distributions of W2-W3
colour for sources with HI absorption detections and non-detections.
We report a high detection rate of HI absorption in those galaxies
with WISE infrared colours W2-W3>2, typical of gas-rich systems, along
with a compact radio structure. The HI detection rate for
low-excitation radio galaxies (LERGs) with W2-W3>2 and compact radio
structure is high (70.6±20.4 per cent). In high-excitation radio
galaxies (HERGs), compact radio structure in the nuclear or
circumnuclear region could give rise to absorption by gas in the dusty
torus, in addition to gas in the interstellar medium. However, the
higher specific star-formation rate (sSFR) for LERGs with W2-W3>2
suggests that HI absorption may be largely due to star-forming gas in
their hosts. LERGs with extended radio structure tend to have
significantly lower values of W2-W3 compared with those with compact
structure. Extended radio sources and those with W2-W3<2 have low HI
detection rates.
Description:
Tables for optical line characterictics, WISE colours, stellar masses,
star formation and specific star formation rates of 100 sources
studied in HI absorption by Gereb et al. (2015, Cat. J/A+A/575/A44).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 152 31 Optical line characteristics of sources detected
in HI absorption by Gereb et al.,
2015, Cat. J/A+A/575/A44
tablea2.dat 152 69 Optical line characteristics of sources not
detected in HI absorption by Gereb et al.
2015, Cat. J/A+A/575/A44
tablea3.dat 100 100 WISE magnitudes, stellar masses (SM),
star formation rates (SFR) and specific star
formation rates (sSFR) for all 100 sources
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See also:
II/328 : AllWISE Data Release (Cutri+ 2013)
J/A+A/575/A44 : HI absorption in flux-selected radio AGNs (Gereb+, 2015)
J/MNRAS/421/1569 : Properties of 18286 SDSS radio galaxies (Best+, 2012)
http://wwwmpa.mpa-garching.mpg.de/SDSS/DR7 : SDSS DR7 Home Page
Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/100] Sequence number
5- 6 I2 h RAh Right ascension (J2000.0) (1)
8- 9 I2 min RAm Right ascension (J2000.0) (1)
11- 14 F4.1 s RAs Right ascension (J2000.0) (1)
16 A1 --- DE- Declination sign (J2000.0) (1)
17- 18 I2 deg DEd Declination (J2000.0) (1)
20- 21 I2 arcmin DEm Declination (J2000.0) (1)
23- 24 I2 arcsec DEs Declination (J2000.0) (1)
26- 32 F7.3 10-20W/m2 FHb Hβ flux (2)
34- 39 F6.3 10-20W/m2 e_FHb Hβ flux error
42- 49 F8.3 10-20W/m2 FO[III] O[III] flux (2)
51- 56 F6.3 10-20W/m2 e_FO[III] O[III] flux error (2)(5)
59- 64 F6.3 0.1nm EWO[III] O[III] equivalent width (2)
66- 70 F5.3 0.1nm e_EWO[III] O[III] equivalent width error
73- 79 F7.3 10-20W/m2 FO[I] O[I] flux (2)(6)
81- 86 F6.3 10-20W/m2 e_FO[I] O[I] flux error (2)(5)
89- 96 F8.3 10-20W/m2 FHa Hα flux (2)
98-103 F6.3 10-20W/m2 e_FHa Hα flux error (2)(5)
106-113 F8.3 10-20W/m2 FN[II] N[II] flux (2)
115-120 F6.3 10-20W/m2 e_FN[II] N[II] flux error (2)(5)
123-132 F10.3 10-20W/m2 FS[II] S[II] flux (2)(6)
134-144 F11.3 10-20W/m2 e_FS[II] S[II] flux error (2)(5)
147-150 A4 ---- OClass Optical class (3)
152 A1 --- RClass Radio Structural class (4)
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Note (1): Cooridinates for radio sources from Gereb et al.
(2015, Cat. J/A+A/575/A44)
Note (2): Line parameters for different optical lines (with errors) from MPA-JHU
group database (Brinchmann et al., 2004,
http://wwwmpa.mpa-garching.mpg.de/SDSS/DR7/sfrs.html).
Only absolute values for these measurements are provided in this table.
Note (3): Optical classification: HERG/LERG/U(unclassified) following
Best & Heckman (2012, Cat. J/MNRAS/421/1569).
Note (4): Radio structural classification, from Gereb et al.
(2015, Cat. J/A+A/575/A44), as follows:
C = compact)
E = extended)
M = Merger/optical blue objects
Note (5): Flux errors are scaled up by factors as recommended by MPA-JHU group
(Brinchmann et al. 2004, http://wwwmpa.mpa-garching.mpg.de/SDSS/DR7/sfrs.html).
Note (6): in tablea2.dat,
J083139+223423, J091218+483045, J122122+301037, J130622+434751 and
J154912+304716, have O[I] equivalent width sign +, indicating absorption.
J080042.0+321728 and J110305.8+191702 have S[II] equivalent width sign +,
indicating absorption.
J082028+485347 have O[I] and S[II] equivalent width sign +,
indicating absorption.
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/100] Sequence number
5- 23 A19 --- WISE Source name in WISE catalog (1)
25- 30 F6.3 mag W1mag Magnitude at W1(3.4 micron), Vega (2)
32- 36 F5.3 mag e_W1mag Error in magnitude at W1, Vega (2)(6)
39- 44 F6.3 mag W2mag Magnitude at W2(4.6 micron), Vega (2)
46- 50 F5.3 mag e_W2mag Error in magnitude at W2, Vega (2)(6)
52 A1 --- l_W3mag Upper limit flag on W3mag
53- 58 F6.3 mag W3mag Magnitude at W3(12 micron), Vega (2)
60- 64 F5.3 mag e_W3mag ?=- Error in magnitude at W3, Vega (2)(6)
66 A1 --- l_W4mag Upper limit flag on W4mag
67- 71 F5.3 mag W4mag Magnitude at W4(22 micron), Vega (2)
73- 77 F5.3 mag e_W4mag ?=- Error in magnitude at W4, Vega (2)(6)
80- 85 F6.3 [Msun] LogSM Log Stellar mass (3)
87- 92 F6.3 [Msun/yr] LogSFR Log star formation rate (4)
94-100 F7.3 [yr-1] LogsSFR Log specific star formation rate (5)
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Note (1): WISE name of sources from catalog by Cutri et al. (2013, Cat. II/328).
Note (2): WISE vega magnitudes at W1(3.4um), W2(4.6um), W3(12um) and W4(22um)
with errors from Cutri et al. (2013, Cat. II/328)
Note (3): Log stellar masses (SM) from MPA-JPU database (Brinchmann et al.,
2004, http://wwwmpa.mpa-garching.mpg.de/SDSS/DR7/Data/stellarmass.html.
Note (4): Log star formation rates (SFR) from MPA-JPU database (Brinchmann
et al., 2004, http://wwwmpa.mpa-garching.mpg.de/SDSS/DR7/Data/stellarmass.html
Note (5): Log specific star formation rates (sSFR) from MPA-JPU database
(Brinchmann et al., 2004,
http://wwwmpa.mpa-garching.mpg.de/SDSS/DR7/Data/stellarmass.html).
Note (6): For upper limits on magnitudes errors are blank (---).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 03-Jul-2018