J/ApJ/682/1205 Fast transients in the Fornax cluster (Rau+, 2008)
A survey for fast transients in the Fornax cluster of galaxies.
Rau A., Ofek E.O., Kulkarni S.R., Madore B.F., Pevunova O., Ajello M.
<Astrophys. J., 682, 1205-1216 (2008)>
=2008ApJ...682.1205R 2008ApJ...682.1205R
ADC_Keywords: Stars, variable ; Photometry, CCD
Keywords: delta Scuti - stars: flare - stars: variables: other - surveys
Abstract:
The luminosity gap between novae (MR≤-10) and supernovae
(MR≥-14) has been well known since the pioneering research of
Zwicky and Hubble. Nearby galaxy clusters and concentrations offer an
excellent opportunity to search for explosions brighter than classical
novae and fainter than supernovae. Here we present the results of a
B-band survey of 23 member galaxies of the Fornax Cluster, performed
at the Las Campanas 2.5m Irenee du Pont telescope. Observations with a
cadence of 32 minutes discovered no genuine fast transient to a
limiting absolute magnitude of MB=-9.3mag. We provide a detailed
assessment of the transient detection efficiency and the resulting
upper limits on the event rate as function of peak magnitude. Further,
we discuss the discoveries of five previously unknown foreground
variables which we identified as two flare stars, two W UMa-type
eclipsing binaries and a candidate δ Scuti/SX Phe star.
Description:
Observations were obtained with the Wide Field Reimaging CCD Camera
(WFCCD) at the 2.5m Irenee du Pont telescope in Las Campanas, Chile.
For the survey, we selected 10 fields covering the 23 brightest Fornax
I Cluster members. These fields were imaged with a sequence of 120s
exposures repeated up to 15 times in each of five nights in 2006
October and December.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 99 7 Summary of detected sources
table4.dat 27 385 Data table for the 5 foreground variables found
in the survey
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See also:
J/PASP/110/533 : BR photometry of Fornax bright stars (Stetson+ 1998)
J/A+A/317/54 : Fornax cluster 1 and 3 photometry (Jorgensen+ 1997)
J/AJ/111/1596 : BV photometry in Fornax globulars (Smith+ 1996)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Source identification (<[ROK2008] FA-1> in
Simbad for the 5 new variables)
11- 12 I2 h RAh Hour of right ascension (J2000)
14- 15 I2 min RAm Minute of right ascension (J2000)
17- 21 F5.2 s RAs Second of right ascension (J2000)
23 A1 --- DE- Declination sign (J2000)
24- 25 I2 deg DEd Degree of declination (J2000)
27- 28 I2 arcmin DEm Arcminute of declination (J2000)
30- 33 F4.1 arcsec DEs Arcsecond of declination (J2000)
35- 39 F5.2 mag Bmag Observed peak B-band magnitude
41- 44 F4.2 mag e_Bmag Uncertainty in Bmag
45 A1 --- f_Bmag [de] Flag on Bmag (1)
47- 51 F5.2 mag Bq ? Mean or quiescence B-band magnitude (2)
53- 56 F4.2 mag e_Bq ? Uncertainty in Bq
58- 78 A21 --- Class Class of object
80- 83 F4.1 kpc Dist Projected distance to center of nearest galaxy
85- 94 A10 --- --- [kpc to NGC]
96- 99 I4 --- NGC NGC number of nearest galaxy
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Note (1): Flags as follows:
d = Observed B-band magnitude on 2006 October 23.13 UT.
e = Observed B-band magnitude on 2006 November 17.58 UT.
Note (2): Observed mean (for periodic variables) or quiescence (for
eruptive variables) B-band magnitude.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Name Source name
6- 16 F11.5 d MJD Modified Julian Date
18- 22 F5.2 mag Bmag The B band magnitude
24- 27 F4.2 mag e_Bmag Error in Bmag
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 24-Nov-2010