J/MNRAS/456/3335 SPIRE observations of Herschel-BAT sample (Shimizu+, 2016)
Herschel far-infrared photometry of the Swift Burst Alert Telescope active
galactic nuclei sample of the local universe.
II. SPIRE observations.
Shimizu T.T., Melendez M., Mushotzky R.F., Koss M.J., Barger A.J.,
Cowie L.L.
<Mon. Not. R. Astron. Soc., 456, 3335-3353 (2016)>
=2016MNRAS.456.3335S 2016MNRAS.456.3335S (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Galaxies, IR ; Photometry, millimetric/submm
Keywords: methods: data analysis- galaxies: active - galaxies: photometry -
galaxies: Seyfert - infrared: galaxies
Abstract:
We present far-infrared (FIR) and submillimetre photometry from the
Herschel Space Observatory's Spectral and Photometric Imaging Receiver
(SPIRE) for 313 nearby (z<0.05) active galactic nuclei (AGN). We
selected AGN from the 58 month Swift Burst Alert Telescope (BAT)
catalogue, the result of an all-sky survey in the 14-195keV energy
band, allowing for a reduction in AGN selection effects due to
obscuration and host galaxy contamination. We find 46 per cent
(143/313) of our sample is detected at all three wavebands and
combined with our Photoconductor Array Camera and Spectrometer (PACS)
observations represents the most complete FIR spectral energy
distributions of local, moderate-luminosity AGN. We find no
correlation among the 250, 350, and 500µm luminosities with
14-195keV luminosity, indicating the bulk of the FIR emission is not
related to the AGN. However, Seyfert 1s do show a very weak
correlation with X-ray luminosity compared to Seyfert 2s and we
discuss possible explanations. We compare the SPIRE colours
(F250/F350 and F350/F500) to a sample of normal star-forming
galaxies, finding the two samples are statistically similar,
especially after matching in stellar mass. But a colour-colour plot
reveals a fraction of the Herschel-BAT AGN are displaced from the
normal star-forming galaxies due to excess 500µm emission (E500).
Our analysis shows E500 is strongly correlated with the 14-195keV
luminosity and 3.4/4.6µm flux ratio, evidence the excess is related
to the AGN. We speculate these sources are experiencing millimetre
excess emission originating in the corona of the accretion disc.
Description:
We selected our sample of 313 AGN from the 58 month Swift/BAT
Catalogue (https://swift.gsfc.nasa.gov/results/bs58mon) (Baumgartner
et al., 2012, in prep.), imposing a redshift cutoff of z<0.05. All
different types of AGN were chosen only excluding Blazars/BL Lac
objects which most likely introduce complicated beaming effects. To
determine their AGN type, for 252 sources we used the classifications
from the BAT AGN Spectroscopic Survey (Koss et al., in preparation)
which compiled and analysed optical spectra for the Swift/BAT 70 month
catalogue (Berney et al., 2015MNRAS.454.3622B 2015MNRAS.454.3622B).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 86 313 The Herschel-BAT sample
table2.dat 111 313 SPIRE flux densities
--------------------------------------------------------------------------------
See also:
J/ApJ/794/152 : PACS observations of Herschel-BAT sample (Melendez+, 2014)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Name
26- 27 I2 h RAh Right ascension (J2000)
29- 30 I2 min RAm Right ascension (J2000)
32- 35 F4.1 s RAs Right ascension (J2000)
37 A1 --- DE- Declination sign (J2000)
38- 39 I2 deg DEd Declination (J2000)
41- 42 I2 arcmin DEm Declination (J2000)
44- 45 I2 arcsec DEs Declination (J2000)
47- 52 F6.4 --- z Redshift
54- 59 F6.2 Mpc Dist Luminosity distance
61- 67 A7 --- MType AGN classification
68 A1 --- n_MType [a] Note on classification (1)
72- 75 I4 --- OD Herschel Operational Day number for when
the observation started
77- 86 I10 --- OBSID Herschel Observation Identification number
--------------------------------------------------------------------------------
Note (1): a = for classification from the 70 month Swift/BAT catalog,
all others are from Berney et al., 2015MNRAS.454.3622B 2015MNRAS.454.3622B.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Name
26- 27 I2 h RAh Right ascension (J2000)
29- 30 I2 min RAm Right ascension (J2000)
32- 35 F4.1 s RAs Right ascension (J2000)
37 A1 --- DE- Declination sign (J2000)
38- 39 I2 deg DEd Declination (J2000)
41- 42 I2 arcmin DEm Declination (J2000)
44- 45 I2 arcsec DEs Declination (J2000)
47 A1 --- l_F250 Limit flag on F250 (5σ upper limit for
undetected sources)
48- 54 F7.3 Jy F250 SPIRE 250um flux density
56- 61 F6.3 Jy e_F250 ? 1σ uncertainty on F250
63- 65 A3 --- Met250 Method used to extract photometry at 250um (1)
67- 68 A2 --- Flg250 Flag for the photometry at 250um (2)
70 A1 --- l_F350 Limit flag on F350 (5σ upper limit for
undetected sources)
71- 77 F7.3 Jy F350 SPIRE 350um flux density
79- 83 F5.3 Jy e_F350 ? 1σ uncertainty on F350
85- 87 A3 --- Met350 Method used to extract photometry at 350um (1)
89- 90 A2 --- Flg350 Flag for the photometry at 350um (2)
92 A1 --- l_F500 Limit flag on F500 (5σ upper limit for
undetected sources)
93- 98 F6.3 Jy F500 SPIRE 500um flux density
100-104 F5.3 Jy e_F500 ? 1σ uncertainty on F500
106-108 A3 --- Met500 Method used to extract photometry at 500um (1)
110-111 A2 --- Flg500 Flag for the photometry at 500um (2)
--------------------------------------------------------------------------------
Note (1): Method used to extract the photometry as follows:
TF = timeline fitting
PAP = point sources aperture photometry
EAP = extended source aperture photometry
See text for details on the differences.
Note (2): Flag for the photometry as follows:
A = source was detected at greater than 5σ
U = 5σ upper limit
C = likely foreground cirrus contamination
d = nearby companion however unlikely to affect photometry
D = nearby companion that is likely strongly affecting photometry
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Melendez et al., Paper I, 2014ApJ...794..152M 2014ApJ...794..152M
(End) Patricia Vannier [CDS] 27-Sep-2016