J/ApJ/692/L84 Photometry of SN 2008D (Malesani+, 2009)
Early spectroscopic identification of SN 2008D.
Malesani D., Fynbo J.P.U., Hjorth J., Leloudas G., Sollerman J.,
Stritzinger M.D., Vreeswijk P.M., Watson D.J., Gorosabel J.,
Michalowski M.J., Thone C.C., Augusteijn T., Bersier D., Jakobsson P.,
Jaunsen A.O., Ledoux C., Levan A.J., Milvang-Jensen B., Rol E.,
Tanvir N.R., Wiersema K., Xu D., Albert L., Bayliss M., Gall C.,
Grove L.F., Koester B.P., Leitet E., Pursimo T., Skillen I.
<Astrophys. J., 692, L84-L87 (2009)>
=2009ApJ...692L..84M 2009ApJ...692L..84M
ADC_Keywords: Supernovae ; Photometry, UBVRI ; Photometry, infrared
Keywords: supernovae: individual (SN 2008D)
Abstract:
On 2008 January 9.56 UT, SN 2008D was discovered while following up an
unusually bright X-ray transient (XT) in the nearby spiral galaxy
NGC 2770. We present early optical spectra (obtained 1.75 days after
the XT) which allowed the first identification of the object as a
supernova (SN) at redshift z=0.007. These spectra were acquired during
the initial declining phase of the light curve, likely produced in the
stellar envelope cooling after shock breakout, and rarely observed.
They exhibit a rather flat spectral energy distribution with broad
undulations, and a strong, W-shaped feature with minima at 3980 and
4190Å (rest frame). We also present extensive spectroscopy and
photometry of the SN during the subsequent photospheric phase. Unlike
SNe associated with gamma-ray bursts, SN 2008D displayed prominent He
features and is therefore of Type Ib.
Description:
Imaging observations were conducted using the NOT, the VLT, the
Liverpool Telescope (LT), and the United Kingdom Infrared Telescope
(UKIRT). We performed spectroscopy of the source as soon as possible,
starting 1.75 days after the XT, using the FORS2 spectrograph on the
ESO Very Large Telescope (VLT), in January 11.31, 11.32 UT. Subsequent
spectroscopic monitoring of the object was carried out at the Nordic
Optical Telescope (NOT ; between January 13.07 and March 18.87 UT) and
the William Herschel Telescope (WHT, in Jan 26.15). On January 18.22
UT (8.65 days after the XT), we secured a high-resolution spectrum
using the UVES instrument on the VLT.
Objects:
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RA (2000) DE Designation(s)
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09 09 30.6 +33 08 20 SN 2008D = XRF 080109
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 50 121 Log of optical and near-infrared imaging observations
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See also:
B/sn : Asiago Supernova Catalogue (Barbon et al., 1999-)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 "datime" Epoch Mean epoch of observation (UT)
18- 25 F8.5 d Age Time since the X-ray outburst; Jan 9, 13:32:49 UT
27 A1 -- Filt [UBVRIJHK] Filter used in observation
29- 33 F5.2 mag mag Observed apparent magnitude in Filt (1)
35- 38 F4.2 mag e_mag Error in mag
40- 50 A11 -- Inst Telescope and instrument
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Note (1): These values have not been corrected for Galactic extinction.
There is an additional calibration uncertainty of 0.10, 0.03, 0.04,
0.03, and 0.04mag in U, B, V, R, and I, respectively.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-Feb-2011