J/AcA/64/197 OGLE-IV 2012-2014 transients (Wyrzykowski+, 2014)
OGLE-IV real-time transient search.
Wyrzykowski L., Kostrzewa-rutkowska Z., Kozlowski S., Udalski A.,
Poleski R., Skowron J., Blagorodnova N., Kubiak M., Szymanski M.K.,
Pietrzynski G., Soszynski I., Ulaczyk K., Pietrukowicz P., Mroz P.
<Acta Astron., 64, 197-232 (2014)>
=2014AcA....64..197W 2014AcA....64..197W (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Novae
Keywords: surveys - supernovae: general - novae, cataclysmic variables
Abstract:
We present the design and first results of a real-time search for
transients within the 650 sq. deg. area around the Magellanic Clouds,
conducted as part of the OGLE-IV project and aimed at detecting
supernovae, novae and other events. The average sampling of about four
days from September to May, yielded a detection of 238 transients in
2012/2013 and 2013/2014 seasons. The superb photometric and
astrometric quality of the OGLE data allows for numerous applications
of the discovered transients.
We use this sample to prepare and train a Machine Learning-based
automated classifier for early light curves, which distinguishes major
classes of transients with more than 80% of correct answers.
Spectroscopically classified 49 supernovae Type Ia are used to
construct a Hubble Diagram with statistical scatter of about 0.3mag
and fill the least populated region of the redshifts range in the
Union sample. We investigate the influence of host galaxy environments
on supernovae statistics and find the mean host extinction of
AI=0.19±0.10mag and AV=0.39±0.21mag based on a subsample of
supernovae Type Ia. We show that the positional accuracy of the survey
is of the order of 0.5pixels (0.13") and that the OGLE-IV Transient
Detection System is capable of detecting transients within the nuclei
of galaxies. We present a few interesting cases of nuclear transients
of unknown type.
All data on the OGLE transients are made publicly available to the
astronomical community via the OGLE website.
Description:
Here we present the results of the real-time transient search in the
first two years of the monitoring program of about 650 sq. deg. around
the Magellanic Clouds conducted within the OGLE-IV survey.
All selected on-going transients are made available to the community
via the web-site updated more or less daily:
http://ogle.astrouw.edu.pl/ogle4/transients/
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 165 238 *Information on all OGLE-IV transients found by
the Transients Detection System in real-time
over the period of two seasons 2012/2013 and
2013/2014, with their basic information
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Note on table1.dat: updated web-site :
http://ogle.astrouw.edu.pl/ogle4/transients .
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See also:
http://ogle.astrouw.edu.pl/ogle4/transients : updated transient database
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Name of the transient
(YY-SN-NNN or YY-NOVA-NN)
13- 28 A16 --- DBID Internal OGLE-IV database ID in format
field.chip.star number
30- 31 I2 h RAh Right ascension (J2000.0)
33- 34 I2 min RAm Right ascension (J2000.0)
36- 40 F5.2 s RAs Right ascension (J2000.0)
42 A1 --- DE- Declination sign (J2000.0)
43- 44 I2 deg DEd Declination (J2000.0)
46- 47 I2 arcmin DEm Declination (J2000.0)
49- 52 F4.1 arcsec DEs Declination (J2000.0)
54- 63 F10.5 d DiscDate Discovery date (HJD-2450000)
65- 69 F5.2 mag Imag Discovery magnitude in I band
71- 74 I4 --- ATEL ?=- ATel number for discovery
76- 78 A3 --- pClass Photometric classification with the
highest probability
80- 83 F4.2 --- Prob ?=- Photometric classification probability
85- 92 A8 --- SpType Spectral type of the transient from the
follow-up observations
94-101 F8.6 --- z ?=- Redshift from spectroscopic classification
or found in NED for the nearest galaxy
103-112 A10 --- SpNo ?=- Atel or CBet number for the spectroscopic
classification or "NED" if NED redshift
available only
115-119 F5.2 arcsec Offset ?=- Offset in arcsec from the nucleus of the
host
120 A1 --- n_Offset [)] ) when offset from the nearest galaxy
found in NED
122-126 F5.2 kpc Offsetk ? Offset from the host's center in kpc if
redshift available
128-132 F5.2 --- Offset* ?=- Offset from the nucleus in units of
half-light radius RSer
134-138 F5.2 arcsec RSer ?=- Half-light radius of the host obtained in
GALFIT model
140-142 A3 --- WISE Classification of the nearest galaxy using
WISE colors (1)
144-165 A22 --- Com Comment with visual classification type based
on the entire light curve
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Note (1): Classification of the nearest galaxy using WISE colors after
Assef et al. (2010ApJ...713..970A 2010ApJ...713..970A, Cat. J/ApJ/713/970) as follows:
S = spiral
Ell = elliptical
AGN = active galactic nucleus
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Nov-2015