J/ApJS/252/32 MIR outbursts in nearby SDSS gal. (MIRONG). I. (Jiang+, 2021)
Mid-infrared outbursts in nearby galaxies (MIRONG).
I. Sample selection and characterization.
Jiang N., Wang T., Dou L., Shu X., Hu X., Liu H., Wang Y., Yan L., Sheng Z.,
Yang C., Sun L., Zhou H.
<Astrophys. J. Suppl. Ser., 252, 32 (2021)>
=2021ApJS..252...32J 2021ApJS..252...32J
ADC_Keywords: Active gal. nuclei; Photometry, infrared; Magnitudes, absolute;
Velocity dispersion; Black holes; Stars, masses
Keywords: Time domain astronomy ; Tidal disruption ; Active galactic nuclei ;
Infrared astronomy
Abstract:
Optical time-domain astronomy has grown rapidly in the past decade,
but the dynamic infrared sky is rarely explored. Aiming to construct a
sample of mid-infrared outbursts in nearby galaxies (MIRONG), we have
conducted a systematical search of low-redshift (z<0.35) Sloan Digital
Sky Survey spectroscopic galaxies that have experienced recent
mid-infrared (MIR) flares using their Wide-field Infrared Survey
Explorer (WISE) light curves. A total of 137 galaxies have been
selected by requiring a brightening amplitude of 0.5mag in at least
one WISE band with respect to their quiescent phases. Only a small
fraction (10.9%) has corresponding optical flares. Except for the four
supernovae (SNe) in our sample, the MIR luminosities of the remaining
sources (L4.6µm>1042erg/s) are markedly brighter than known
SNe, and their physical locations are very close to the galactic
center (median <0.1"). Only four galaxies are radio-loud, indicating
that synchrotron radiation from relativistic jets could contribute to
MIR variability. We propose that these MIR outbursts are dominated by
the dust echoes of transient accretion onto supermassive black holes,
such as tidal disruption events (TDEs) and turn-on (changing-look)
active galactic nuclei. Moreover, the inferred peak MIR luminosity
function is generally consistent with the X-ray and optical TDEs at
the high end, albeit with large uncertainties. Our results suggest
that a large population of transients has been overlooked by optical
surveys, probably due to dust obscuration or intrinsically optical
weakness. Thus, a search in the infrared band is crucial for us to
obtain a panoramic picture of nuclear outburst. The multiwavelength
follow-up observations of the MIRONG sample are in progress and will
be presented in a series of subsequent papers.
Description:
MIR outbursts in nearby galaxies (MIRONG) uses both the public WISE
and NEOWISE databases to search for more recent outburst events in
galaxies.
WISE performed a full-sky imaging survey in four broad bandpasses
centered at 3.4, 4.6, 12, and 22um (labeled W1-W4) from 2010 January
to August. WISE continued surveying the sky in its bluest three bands
during 2010 August and September. After that, NEOWISE hunted asteroids
until 2011 February, with only the W1 and W2 channels. Following a 33
month hibernation period, the WISE instrument recommenced survey
operations in 2013 December (Mainzer+ 2014, J/ApJ/792/30). This
posthibernation mission is referred to as NEOWISE-Reactivation (NEOWISE-R).
Our sample selection is based on the WISE and NEOWISE-R data from 2010
to the end of 2018.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 123 137 The properties of MIR flares
table3.dat 99 137 The fitted dust parameters
table5.dat 66 137 The properties of the host galaxies and BH
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See also:
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
II/328 : AllWISE Data Release (Cutri+ 2013)
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
J/ApJ/670/92 : New sample of low-mass black holes in AGN (Greene+, 2007)
J/ApJ/696/870 : Catalina Real-time Transient Survey (CRTS) (Drake+, 2009)
J/ApJ/793/38 : Palomar Transient Factory photometric obs. (Arcavi+, 2014)
J/ApJ/788/159 : 17 Seyfert 1 galaxies light curves (Koshida+, 2014)
J/ApJ/792/30 : NEOWISE magnitudes for near-Earth objects (Mainzer+, 2014)
J/ApJ/788/45 : Luminosity & redshift of galaxies from WISE/SDSS (Toba+, 2014)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/ApJS/219/8 : SFR for WISE + SDSS spectroscopic galaxies (Chang+, 2015)
J/ApJ/813/82 : z<0.06 broad-line AGN emission-line measures (Reines+, 2015)
J/ApJ/831/168 : 6GHz JVLA obs. of low-z SDSS quasars (Kellermann+, 2016)
J/ApJ/844/46 : Phot. of the transient event iPTF16fnl (Blagorodnova+, 2017)
J/ApJ/839/88 : 14 unusual IR transients with Spitzer (Kasliwal+, 2017)
J/MNRAS/481/307 : Gaia Nuclear Transients (GNTs) (Kostrzewa-Rutkowska+, 2018)
J/ApJ/866/44 : WISE/DEIMOS Redshift Catalog DR2 & extended data (Lake+, 2018)
J/ApJ/852/72 : Luminosities tidal disruption flares (van Velzen, 2018)
J/ApJS/243/21 : A complete sample of broad-line AGN from SDSS-DR7 (Liu+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [SDSS]
6- 24 A19 --- SDSS SDSS name (JHHMMSS.ss+DDMMSS.s)
26- 35 F10.6 deg RAdeg Right ascension in decimal degrees (J2000)
37- 44 F8.5 deg DEdeg Declination in decimal degrees (J2000)
46- 52 F7.5 --- z [0.0079/0.4] SDSS redshift
54- 57 F4.2 mag DelW1 [0.1/3] Amplitude of variability in W1 (3.4um)
59- 62 F4.2 mag e_DelW1 [0.01/0.2] DelW1 uncertainty
64- 67 F4.2 mag DelW2 [0.5/3.6] Amplitude of variability in W2 (4.6um)
69- 72 F4.2 mag e_DelW2 [0.01/0.3] DelW2 uncertainty
74- 79 F6.2 mag W1Mag [-27.4/-17.6] Peak absolute magnitude in W1
81- 84 F4.2 mag e_W1Mag [0.01/0.6] Uncertainty on the W1Mag
86- 91 F6.2 mag W2Mag [-28.3/-18.4] Peak absolute magnitude in W2
93- 96 F4.2 mag e_W2Mag [0.01/0.3] Uncertainty on the W2Mag
98- 102 F5.2 [10-7W] W1Lum [40.5/44.5] Peak monochromatic luminosity of W1
104- 107 F4.2 [10-7W] e_W1Lum [0/0.3] W1Lum uncertainty
109- 113 F5.2 [10-7W] W2Lum [40.5/44.5] Peak monochromatic luminosity of W2
115- 118 F4.2 [10-7W] e_W2Lum [0/0.2] W2Lum uncertainty
120- 123 F4.2 arcsec Deld [0.01/1.5] Offset distance between the maximum
outburst epoch and the quiescent state
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [SDSS]
6- 15 A10 --- AName SDSS abbreviated name (JHHMM+DDMM)
17- 20 I4 K Tbb [560/2541] Dust temperature fitted with the
blackbody model at the epoch of W2 luminosity
maximum
22- 24 I3 K e_Tbb [5/476] Tbb uncertainty
26- 30 F5.2 [10-7W] logLbb [40.6/44.6] Luminosity fitted with the
blackbody model at the epoch of W2 luminosity
maximum
32- 35 F4.2 [10-7W] e_logLbb [0.02/0.5] LogLbb uncertainty
37- 41 F5.2 [Msun] logMbb [-5.9/-1.1] Mass fitted with the blackbody
model at the epoch of W2 luminosity maximum
43- 46 F4.2 [Msun] e_logMbb [0.02/0.6] LogMbb uncertainty
48- 52 F5.2 [pc] logRbb [-3.1/-0.6] Distance of the dust to the
central heating source (1)
54- 57 F4.2 [pc] e_logRbb [0.01/0.4] LogRbb uncertainty
59- 62 I4 K Td [516/1657] Dust temperature fitted with the
dust absorption coefficient
64- 66 I3 K e_Td [4/179] Td uncertainty
68- 72 F5.2 [10-7W] logLd [40.6/44.6] Luminosity fitted with the dust
absorption coefficient
74- 77 F4.2 [10-7W] e_logLd [0.01/0.5] LogLd uncertainty
79- 83 F5.2 [Msun] logMd [-4.9/-0.3] Mass fitted with the dust
absorption coefficient
85- 88 F4.2 [Msun] e_logMd [0.02/0.6] LodMd uncertainty
90- 94 F5.2 [pc] logRd [-2.6/-0.2] Distance of the dust to the
central heating source (1)
96- 99 F4.2 [pc] e_logRd [0.02/0.6] LogRd uncertainty
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Note (1): Distance of the dust to the central heating source assuming
spherically symmetric distribution and a covering factor of 1.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [SDSS]
6- 15 A10 --- AName SDSS abbreviated name (JHHMM+DDMM)
17- 22 F6.2 mag rMag [-22.9/-15.9] SDSS absolute r-band
magnitude after k-correction to 0.1
24- 27 F4.2 mag g-r [0.3/1.3] SDSS g-r color index
after k-correction to 0.1
29- 33 F5.1 km/s sigma ? Stellar velocity dispersion
35- 40 F6.3 [Msun] logM* [7.9/11.6] Stellar mass
42- 46 F5.2 [Msun/yr] logSFR [-4.5/1.9] Log of stellar formation rate
48- 51 F4.2 [Msun] logMBH [4.3/9] Estimated BH mass
53- 64 A12 --- Type Classification in the BPT diagram
66 A1 --- n_Type [b] b: robust broad Hα detection
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 23-Apr-2021