SN 2008D

S.   Valenti   (Universita'  degli  studi  di   Ferrara),  V.   D'Elia
(INAF-Ossevatorio    Astronomico   di    Roma),   M.     Della   Valle
(INAF-Osservatorio Astronomico di Capodimonte, Napoli), S.     Benetti
(INAF-Osservatorio Astronomico di  Padova), G.  Chincarini (Universita
degli  Studi  di  Milano  Bicocca),  P.A.  Mazzali  (INAF-Osservatorio
Astronomico   di  Trieste)   and   L.  A.  Antonelli (INAF-Ossevatorio
Astronomico di Roma) and behalf of a larger collaboration report:

We obtained an optical spectrum of SN2008D (crf. Li & Filippenko, CBET
1202; Soderberg et  al., GCN 7165
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 ; Malesani et  al., GCN 7169
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 ; Valenti
et al., GCN 7171
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 ; Blondin et  al., CBET 1205, see also GCN 7160
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 -7168).
The spectrum (range 350-1000 nm) taken on Jan 25.21 with the VLT+FORS2
dereddened by an E(B-V)= 0.5 is identical to the spectrum of SN 1999ex
-1 day  before maximum (Hamuy M. et  al.,2002, AJ,124,417H), dereddend
by E(B-V)=  0.3 (Stritzinger, M.  AJ 2002,124,2100).   We confirm that
the spectrum of SN 2008D in now more similar to that of a normal SN Ib
as  reported by Modjaz  et al  (GCN7212
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 ).  A  comparison is  shown at:
http://www.eso.org/~svalenti/homepage/comparison_99ex_08D_2.jpg

M. Modjaz, R. Chornock, R. J. Foley, A. V. Filippenko, and W. Li (UC
Berkeley); and G. Stringfellow (U of Colorado) report on behalf of a
larger collaboration:

"We obtained optical spectra of SN 2008D (Li & Filippenko, CBET 1202;
Soderberg et al., GCN 7165
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 ; Malesani et al., GCN 7169
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 ; Valenti et al.,
GCN 7171
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 ; Blondin et al., CBET 1205, see also GCN 7160
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 -7168). 
A spectrum (range 350-970 nm) taken on Jan 21.22 UT with the ARC
3.5-m telescope (+ DIS) at APO shows it to be a type-Ib supernova.
The fully reduced spectrum shows the development of conspicuous lines
of He I (rest 447.1, 587.6, 667.8, 706.5 nm) with the maximum absorptions
blueshifted by roughly 10,000-11,000 km/s (assuming a recession velocity
for the host galaxy of 1947 km/s). 

This spectrum, when de-reddened by A_V ~ 2 mag, is very similar to
spectra of SN Ib 2005hg (CBET 271; Modjaz et al., in prep), about 1
week before maximum. Cross-correlation with a library of supernova
spectra using the "Supernova Identification" code (SNID; Blondin and
Tonry 2007, Ap.J. 666, 1024) indicates that the spectrum of SN 2008D
is also similar to that of SN Ib 1998dt (Matheson et al. 2001,
A.J. 121, 1648) at maximum light. We furthermore detect strong
absorption at 615 nm which could be due to Si II (rest 635.5 nm) at
10,000 km/s or alternatively, very high-velocity H-alpha at 19,000
km/s. SN 2008D is the SN associated with the X-Ray Transient 080109
(Berger & Soderberg, GCN 7159
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 ; Kong & Marcone, ATEL 1355) and was
previously classified as peculiar type-Ic supernova (Blondin et al.,
Valenti et al. CBET 1205) based on very early spectra, and later as a
normal type-Ic SN (Malesani et al. GCN 7184
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 ) with possibly some He as
seen in NIR spectra (Marion et al. GCN 7188
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 )."

E. Berger and A. M. Soderberg (Princeton) report on behalf of a larger 
collaboration:

"We used the ARC 3.5-m telescope at Apache Point Observatory to obtain 
spectroscopic observations of the X-ray transient in NGC2770 (GCN 7159
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 ). 
We obtained 4x1200 sec exposures with the DIS red+blue cameras providing a 
wavelength range of 3600-9000A.  The spectra therefore cover a wide range 
of nebular emission lines relevant for metallicity measurements (i.e. 
[OII], H-beta, [OIII], H-alpha, [NII], and [SII]).  Following the 
prescriptions of Kewley & Dopita (2002) we use several indicators (e.g. 
[NII]/[OII], R23) to measure the metallicity and ionization parameter of 
bright HII regions within +/-8 arcsec (about 1 kpc) of the X-ray transient 
position.  We find metallicities of 12+log(O/H)=8.9+/-0.2, or about 
0.6-1.6 times the solar metallicity.  The error bar includes both the 
spread in metallicity and the systematic uncertainty between the various 
indicators.  This value is higher, and more robust, than the estimate in 
GCN 7189
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  which relied on an assumed metallicity gradient."

Lokesh, V. Venkat, R. Purohit, J. Jain, S. Vadawale and B.G. Anandarao
      Physical Research Laboratory, Ahmedabad, India.

   We made infrared photometry at Mt. Abu 1.2 m Cassegrain telescope using
NICMOS camera on the Transient XRF 080109/SN 2008D in NGC 2770 (Berger &
Soderberg, GCN 7159
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 ; Modjaz et al., GCN 7175
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  and Antonelli et al., GCN
7177
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 ) during 2008 Jan 11, Jan 13 and Jan 15. Sky conditions were good
during the first two nights but not so much on the third. The calibration
was made on the two bright stars in the field of view against 2MASS values
for 08-01-11 and using the photometric standard AS 20-0 for the other
nights.  The filters used (and overall integration times), magnitudes with
errors are given below for each date (UT).

  Date (UT)         Filter         Magnitude
2008-01-11.892    J (360 sec)     16.71+/-0.12
2008-01-13.894    J (360 sec)     16.57+/-0.10
2008-01-13.979    H (360 sec)     15.87+/-0.10
2008-01-15.864    J (480 sec)     16.12+/-0.20
2008-01-15.092    H (480 sec)     16.02+/-0.22

These magnitudes are consistent with GCN 7175
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  and GCN 7177
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 . We continue to
monitor this source in the JH bands.

J. L. Prieto (Ohio State) reports:

The host galaxy of SN 2008D, NGC 2770, is included in the latest version
of our catalog of supernova hosts:

http://www.astronomy.ohio-state.edu/~prieto/snhosts/sort_name.html#2008D

The central oxygen abundance of NGC 2770, as measured by Tremonti et al.
(2004, ApJ, 613, 898) using nebular emission lines, is 12 + log(O/H) = 9.0
and its absolute magnitude is MB = -20.7 (HyperLeda catalog), putting this
Sc galaxy on the luminosity-metallicity relationship of star forming
galaxies (e.g., Tremonti et al. 2004). These characteristics are typical
of the hosts of other type Ib/c supernovae (Prieto, Stanek & Beacom 2008,
ApJ, in press, arXiv: 0707.0690), and in contrast with the low-metallicity
of the hosts of long-GRBs with supernovae (e.g., Stanek et al. 2006, AcA,
56, 333). We note, however, that SN 2008D exploded fairly far from the
center of NGC2770 (galactocentric distance of ~10kpc), which may have a
strong metallicity gradient, as suggested by its late-type Sc
classification. From the measured radial metallicity gradients of galaxies
with similar morphological class (Zaritsky, Kennicutt, & Huchra 1994, ApJ,
420, 87), we estimate an oxygen abundance of 8.4 < 12 + log(O/H) < 8.8 (in
the scale of Tremonti et al.) at the site of the supernova explosion. Even
though this is only an approximation, this value is consistent with the
metallicities measured at the sites of broad-lined SN Ic without GRBs
(Modjaz et al. 2008, AJ, in press, astro-ph/0701246).

Indepently of the true nature of the X-ray transient associated with the
peculiar type Ic supernova 2008D (e.g., Blondin et al., CBET 1205), an XRF
or shock breakout (Burrows et al., GCN Circ. 7179
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 ), its remarkable
star-forming host, NGC 2770, deserves to be studied in detail: it has
produced three supernovae of type Ib/c in less than 10 years (SN 1999eh,
2007uy, and 2008D), which most likely result from death of very massive
stars (mass > 30 Msun, e.g., Heger et al. 2003, ApJ, 591, 288).

This message may be cited.

H. Marion (U. Texas/Texas State), P. Garnavich (Notre Dame)
and C. Gerardy (FSU) report:

We obtained near-infrared spectra of supernova 2008D (ATEL 1353; GCN
7160
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 ) with the NASA Infrared Telescope Facility (IRTF) and
SPEX instrument. The data were taken January 14.4 UT and cover
the wavelength range 0.7 to 2.5 microns. A preliminary reduction
of the spectrum shows a strong absorption feature at 1.01 micron.
This feature is seen in several other type Ic events (e.g. SN 1994I,
Millard et al. 1999, ApJ, 527, 746; SN2002ap, Motohara et al.
2002, IAUC 7834) and is probably a combination of HeI, CI and SiI.
A weaker feature at 0.80 micron is likely to be CaII (0.858 micron)
with an absorption minimum at 21000 km/s.

We thank Alan Tokunaga for coordinating these observations at the IRTF.

S. Immler (NASA/UMCP/GSFC) reports on behalf of the Swift team:

Regular Swift UVOT monitoring of the optical counterpart to the X-ray
transient in NGC 2770, SN 2008D (Atel 1353), shows a brightening in
the v and b filters by 0.4 mag and 0.2 mag, respectively, over a 3-day
period (2008-01-13 01:24:08 UT to 2008-01-15 01:25:19 UT).
This rise confirms the onset of a supernova component (GCN 7183
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 ).
The following magnitudes are measured for observations starting on
2008-01-15 01:26:24 UT:

v = 18.3+/-0.1 (496 s exposure time),
b = 19.1+/-0.1 (496 s)
u = 19.6+/-0.2 (496 s),
uvw1 > 20.5 (3-sigma upper limit, 989 s),
uvm2 > 20.3 (3-sigma upper limit, 1247 s), and
uvw2 > 20.9 (3-sigma upper limit, 1983 s).

We further observe a decline of the optical counterpart in the v, b, and
u filters by 0.1 mag, 0.4 mag, and 0.6 mag, respectively, prior to the
rise (2008-01-11 02:40:44 UT to 2008-01-13 01:12:58 UT).

These magnitudes are on the UVOT photometric system (see Poole et al.,
2007, MNRAS, 383, 627) which in the optical is close to the Johnson
UBV system. They have not been corrected for Galactic extinction of
E(B-V) = 0.023 mag (Schlegel et al. 1998, ApJ 500, 525).

A full report on the complete Swift BAT, XRT, and UVOT data will be
released shortly.

D. A. Perley and J. S. Bloom report on behalf of the GRAASP collaboration:

Using Gemini-South (+GMOS), we obtained 2x60 seconds of imaging in g and 
and 1x60 seconds in r of NGC 2770 as acquisition images in preparation 
for later spectroscopic observations.  The sequence started at UT 05:33 
2008-01-11, 40.00 hours after the trigger time derived by Modjaz et al. 
(GCN 7175
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 ). Calibrating relative to the Sloan Digital Sky Survey, we 
measure the following magnitudes for XRF 080109 / SN 2008D (Berger & 
Soderberg, GCN 7159
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 ; Kong & Marcone, ATEL 1355) at this time:

g = 18.72 +/- 0.15
r = 18.10 +/- 0.07

For SN 2007uy, we derive g = 16.31 +/- 0.15, r = 15.86 +/- 0.07.

An image of the field has been posted to:

http://lyra.berkeley.edu/~dperley/sn2008d/ngc2770_2sne.png

We thank E. R. Carrasco at Gemini Observatory for his assistance.

D. N. Burrows (PSU), J. Cummings (GSFC), H. Krimm (GSFC), N. Gehrels 
(GSFC), K. L. Page (U. Leicester), S. Barthelmy (GSFC), E. Berger 
(Princeton), A. Cucchiara (PSU), D. Fox (PSU), S. Immler (GSFC), P. 
T. O'Brien (U. Leicester), and A. M. Soderberg (Princeton) report on 
behalf of the Swift team:

We report on additional analysis of the initial Swift BAT data and 
continuing XRT observations of the X-ray transient in NGC 2770 
(Berger & Soderberg, GCN Circ. 7159
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 ), for which the optical 
counterpart (Deng & Zhu, GCN 7160
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 )  has been spectroscopically 
identified as a Type Ibc supernova (SN2008D;  Malesani et al., GGN 
Circ. 7169).

Quite fortunately, this object was in the BAT field of view in the 
two previous Swift observations (of BZQ J0618+4620 beginning at 
13:04:12.33 and of SN2007ax beginning at 13:12:24.5 UT on 9 Jan 
2008).  The Swift timeline was:

Obs 1:
13:02:02.3: begin slewing to BZQ J0618+4620 (RA, Dec = 94.530, +46.359)
13:04:12.3: end slew, settled on target.  NGC 2770 in BAT field of 
view with 54% coding.
Obs 2:
13:12:02.3: begin slewing to SN2007ax (RA, Dec = 125.679, +22.556)
13:13:24.5: end slew, settled on target.  NGC 2770 in BAT field of 
view with ~90% coding
Obs 3:
13:32:02.3: begin slewing to SN2007uy in NGC 2770 (RA, Dec = 137.407, +33.126)
13:32:48.9: end slew, settled on target.  NGC 2770 in BAT field of 
view with 100% coding.

13:50:02.1: begin slewing to RX J0923.5+5745 (RA, Dec = 140.887, +57.794)

BAT did not trigger on a GRB during the observations of either BZQ 
J0618 or SN2007ax.  An examination of the data from the direction of 
NGC 2770 during those observations shows no sign of any emission from 
this source in the BAT energy range, with upper limits of 1.0e-7 
erg/cm2 during the BZQ observation (Obs 1) and 1.1e-7 erg/cm2 during 
the SN2007ax observation (Obs 2).  During the observation of SN2007uy 
in NGC 2770 (Obs 3), when the X-ray transient occurred in the XRT 
data, the BAT upper limit is 8.9e-8 erg/cm2.  These upper limits are 
for the band 15-150 keV, assuming a power law photon index of 
1.  Extrapolating the X-ray transient spectrum from Obs 3 (Page et 
al., GCN Circ. 7170
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 ) into the 15-150 keV band, the extrapolated 
fluence is 5.2e-8, below the BAT fluence limit for this time interval.

During the slews, XRT collected no data and BAT collected only count 
rates.   There is no sign of a GRB in the BAT field of view during 
the slews, based on count rates during those time intervals.

To summarize, there is no indication of a GRB in the BAT energy range 
(15-350 keV) during the 30 minutes before the X-ray transient is seen 
in the XRT data, or during the observation of SN2007uy, which lasted 
over 1000 s (i.e., coincident with the X-ray transient).  The BAT 
upper limits are consistent with the extrapolation of the spectrum of 
the X-ray transient into the 15-150 keV band.

The nature and onset time of the X-ray transient are not entirely 
clear.  The source was already quite bright (~2 count/s) in the XRT 
band (0.3-10 keV) when the first exposure was taken beginning at 
13:32:48.9 UT, after which it rose rapidly to a peak count rate of 
about 5 count/s for ~90 s before decaying rapidly (Page et al., GCN 
Circ. 7170
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 ).  We note that the estimate for T0 given by Modjaz et al. 
(GCN Circ. 7175
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 ) is therefore only a limit; an earlier T0 cannot be 
excluded due to the lack of prior X-ray data.  The X-ray transient 
lightcurve and hard-to-soft spectral evolution are consistent with 
either a prompt, broad XRF or an X-ray flare (this event is similar 
to the giant X-ray flare in GRB 050502B); if interpreted as a flare, 
T0 could be hundreds of seconds earlier.

XRT observations are continuing.  Analysis of the late XRT data 
(after the first orbit) is complicated by the presence of a nearby 
weak source that contaminates the late-time data from the 
transient.  Our analysis, using a very small source extraction region 
to reduce the contamination from this nearby source, suggests that 
the late-time light curve has a shallow decay reminiscent of the 
plateau phase often seen in GRB X-ray afterglows, but lasting much 
longer than is typical for GRB afterglows (up to at least 200 ks 
after the first XRT detection).  The late-time decay index is -0.67 
+0.29/-0.33.

The X-ray transient peak could be the onset of an XRF, or it could be 
an X-ray flare in an XRF that began somewhat earlier.  The lack of an 
associated GRB in the BAT data suggests that there may be no GRB 
associated with this event (either due to a lack of ultrarelativistic 
ejecta or because it is not beamed towards us), in which case the 
X-ray transient could be related to shock breakout.  Alternatively 
this could indeed be a weak XRF with an unusually soft spectrum 
(Berger & Soderberg, GCN Circ. 7159
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 ).

Weidong Li, Ryan Chornock, Ryan J. Foley, Alexei V. Filippenko, 
Maryam Modjaz, Dovi Poznanski, and Joshua S. Bloom (UC Berkeley) 
report: 

We analyzed the Swift/UVOT images of XRB 080109/SN 2008D in the 
U, B, and V filters taken on Jan 11 and 12 UT. We constructed 
template images for the field from follow-up data taken for 
SN 2007uy, and attempted image subtraction to remove the heavy
galaxy contamination at the site of SN 2008D. We were able to
obtain clean subtracted images as demonstrated at
http://astro.berkeley.edu/~bait/sn2008d.uvot-sub.gif

Using the calibration and photometry recipe of the UVOT 
U, B, V filters as described by Li et al. (2006, PASP 118, 37), 
we obtained the following photometry for SN 2008D. We used
t_0 as determined by Modjaz et al. (GCN 7175
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 ). 

UT date       t(days)   Total exp. time       Mag and err 

Jan 11.569     2.0047      2771.32s           U = 18.65 +/- 0.04   
Jan 11.591     2.0265      2579.13s           B = 19.05 +/- 0.04   
Jan 11.585     2.0203      2349.89s           V = 18.38 +/- 0.05   

Jan 12.408     2.9434       730.82s           U = 19.02 +/- 0.07  
Jan 12.409     2.8443       668.02s           B = 19.34 +/- 0.07  
Jan 12.445     2.8802       605.26s           V = 18.56 +/- 0.08  

The SN is seen to decline in the U (by 0.37 mag), B (by 0.29 mag),
and V (by 0.18 mag) filters between t = 2.0-2.9 d after the XRB. 
As the SN declined faster in U than in V, it became progressively
redder during this period. 

Possible explanations for the decline in the brightness at such early 
times for SN 2008D in the context of a SN Ib/c include the following.
(a) The SN had a bright initial optical flash from shock breakout,
and is now declining due to adiabatic expansion, similar to what
was observed for SN 1999ex (Stritzinger et al. 2002, AJ 124, 2100).
If this is the case, the SN will brighten again when the energy
input from radioactive decay starts becoming visible.
(b) The object is still dominated by the afterglow emission
from the XRB, similar to SN 2003dh/GRB 030329. However, spectroscopy
by Malesani et al. (GCN 7169
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 ), Blondin et al. and Valenti et al. (CBET 
1205) indicate rather strong SN features with no prominent power-law 
continuum.
(c) The SN has a similar behavior to the peculiar SN 2005bf
(Folatelli et al. 2006, ApJ 641, 1039), with two broad peaks in 
the light curves. However, the first peak of SN 2005bf was reached
more than 20 d after its discovery, and SN 2008D may have a 
very early and sharp first peak at t < 2 d. 

[GCN OPS NOTE(14jan08): Per author's request, the Malesani reference
was added to the "(b)" paragraph.]

M. Modjaz, J. S. Bloom, N. R. Butler, D. Starr (UC Berkeley), R. P. 
Kirshner, A. Friedman (Harvard/CfA) report on behalf of a larger 
collaboration:

"From our analysis of the Swift XRT data we find an explosion time for the 
start of XRB 080109 (Berger & Soderberg, GCN 7159
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 ; Kong & Marcone, ATEL 
1355) as viewed by Swift of:

      t_0 = 2008-01-09 13:32:49 UT (+/- 5 sec).

We observed the field of SN 2007uy (Nakano et al. IAUC 8908; Blondin et 
al. CBET 1191) with the 1.3m PAIRITEL on Mt. Hopkins on 2008-01-09 08:45 
UT, i.e. 4.5 hours before t_0. We started observing again on 2008-01-10 
06:23:06 UT, i.e. 17 hours after the burst and for the following nights.

The SN 2008D (Li & Filippenko, IAUC 1202; Soderberg et al., GCN 7165
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 ; 
Malesani et al., GCN 7169
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 ; Valenti et al., GCN 7171
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 ; Blondin et al., CBET 
1205, see also GCN 7160
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 -7168) associated with XRB 080109 is clearly 
detected in mosaic-stacks of each ~1100-sec integration time. From 
preliminary reductions of multi-epoch observations on Jan 11 and Jan 12, 
using ~15-20 2MASS stars in the field for the zeropoint, we derive the 
following error-weighted aperture magnitudes:

Filter  midtime (UTC)           Magnitude       MagError
 J     2008-01-11 8.4           16.63           0.13
 H     2008-01-11 8.4           16.33           0.17
 K_s   2008-01-11 8.3           16.11           0.18

 J     2008-01-12 8.0           16.51           0.06
 H     2008-01-12 7.9           16.15           0.14
 K_s   2008-01-12 7.9           16.22           0.29

No strong variability is detected over those 2 nights but the source was 
clearly not visible at these magnitudes on Jan 9 UT. Further data 
reduction and observations are in progress.  SN 2007uy was measured to be
~1 mag brighter in the J, H, K_s filters on Jan 11 and 12 UT."

A comparison of the 9 Jan, 12 Jan and historical 2MASS imaging can be 
found at:"

       http://pairitel.org/2sne-fig4.tiff

S. Blondin (Harvard-Smithsonian Center for Astrophysics, CfA), on behalf            
of the CfA Supernova Group; T. Matheson (National Optical Astronomy                  
Observatory); and M. Modjaz (University of California at Berkeley),                  
report:

A spectrum (range 320-840 nm) of 2008D (cf. CBET 1202), obtained on Jan.  
11.41 UT by P. Berlind with the MMT 6.5-m telescope (+ Blue Channel 
spectrograph), shows it most likely to be a peculiar type-Ic supernova in 
its early phases, confirming and refining earlier results (Malesani et al, 
GCN 7169
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 ; Valenti et al, GCN 7171
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 ).  The spectrum consists of a relatively 
blue continuum, with P-Cyg profiles (FWHM of approximately 10000 km/s) 
that are characteristic of a supernova spectrum blueward of 550 nm, and an 
extremely broad bump peaking at approximately 630 nm (with an associated 
absorption at 590 nm) that is similar to the Si II line (rest 635.5 nm)  
seen in the spectra of broad-line type-Ic supernovae around maximum light.  
More specifically, the double-absorption feature centered on 420 nm 
resembles that seen in the earliest spectrum of the normal type-Ic 
supernova 1990aa (cf. IAUC 5087, 5111; Matheson et al. 2001, A.J. 121, 
1648), while the broad feature centered on 630 nm resembles the Si II bump 
seen in spectra of the broad-line type-Ic supernova 1998bw (associated 
with GRB 980425; cf. IAUC 6895, 6901; Patat et al. 2001, Ap.J. 555, 900)  
around maximum light (roughly three weeks after the gamma-ray-burst 
detection).

     Blondin et al. add that their spectrum is not consistent with the               
description given by Soderberg et al. in GCN 1765
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 , who report on a                   
"smooth, featureless continuum" with "some suggestion of a broad bump near           
5500 Angstroms".  However, based on other spectra of familiar objects                
fully reduced from the same night, Blondin et al. are confident that their           
flux and wavelength calibrations are accurate.  The separation in time               
between the MMT spectrum and the one described in GCN 1765
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  is only 0.1               
day. Blondin et al. clearly detect narrow emission lines at the supernova            
position, consistent with the NED redshift of 1934 km/s for NGC 2770 (from           
The Updated Zwicky Catalog, http://tdc-www.harvard.edu/uzc/).  Adopting              
this recession velocity, the maximum absorption in the Si II line (rest              
635.5 nm) is blueshifted by roughly 23000 km/s.  Also, interstellar Na I D           
absorption at that redshift is visible in the spectrum with an equivalent            
width of 0.2 nm.  

A comparison plot can be seen at the following URL:  
http://www.cfa.harvard.edu/supernova/spectra/sn2008D_comp.gif; note that, 
in this plot, the spectrum of SN 1990aa had to be blueshifted by 5500 km/s 
in order for prominent spectroscopic features to match up with those 
present in SN 2008D, while that of SN 1998bw has been redshifted by 13000 
km/s for the same reason.

S.  Valenti  (Universita'  di  Ferrara);  D.   Fugazza,  E.   Maiorano
(Istituto Nazionale di Astrofisica - INAF - Osservatorio Astronomico di
Bologna); V.  D'Elia, L.A.  Antonelli (INAF-Ossevatorio Astronomico di
Roma);   S.    Covino   (INAF-Osservatorio  Astronomico   di   Brera);
A. Magazzu' and  N.  Pinilla-Alonso (INAF-Telescopio Nazionele Galileo
(TNG)); M.  Della Valle (INAF-Osservatorio Astrofisico di Arcetri); G.
Chincarini  (Universita' degli  Studi  di Milano  Bicocca); E.   Pian,
P.A.    Mazzali    (INAF-Osservatorio    Astronomico   di    Trieste);
A.  Harutyunyan, S. Benetti  (INAF-Osservatorio Astronomico di Padova)
and behalf of the CIBO collaboration report:

The preliminary reduction of a spectrum
of SN 2008D (Transient in NGC 2770) taken with TNG+LRS
(range 350 - 780 nm) on Jan 11.1 resembles
that of the energetic type Ic SN 2006aj 3 days after explosion (Pian et
al, 2006, Nature 442 1011). The SiII-635.5nm  feature shows  an  higher
expansion velocity  than in  SN  2006aj.  The  bluer  bumbs seen  in SN
2006aj spectrum, centered at  about 440  and 500  nm, are not  yet well
developed, also
suggesting an higher expansion velocity.

S. Immler (NASA/UMCP/GSFC), A. Cucchiara (PSU),  D. Fox (PSU),
A.M. Soderberg (Princeton U), E. Berger (Princeton U), K. Page (Leicester
U), P. O'Brian (Leicester U), D. Burrows (PSU), and N. Gehrels (GSFC),
report on behalf of the Swift team:

An optical counterpart to the X-ray transient in NGC 2770, now SN 2008D
(Atel 1353, 1355, GCN 7159
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 -7167, CBET 1202), was marginally detected
with the Swift Ultraviolet/Optical Telescope (UVOT) in observations
starting 2008-01-09 13:32:53 UT. The following UVOT magnitudes were
measured: b = 20.5�0.3 (412 s exposure time) and u = 20.2�0.4 (412 s).
Upper limits were established for the other UVOT filters, v > 19.9 (412 s,
3-sigma), uvw1 > 20.4, uvm2 > 20.3, and uvw2 > 20.8.

The following UVOT magnitudes were measured for observations
starting 2008-01-11 02:37:28 UT:  v = 18.5�0.2 (216 s exposure time),
b = 18.9�0.1 (353 s), u = 18.6�0.1 (664 s), uvw1 = 19.8�0.2 (1707),
uvm2 > 19.8 (3-sigma UL, 571 s), uvm2 = 20.1�0.3 (864 s), and uvm2 >
20.4 (864 s).

We note that no optical/ultraviolet source was detected at the location of
the transient during routine observations of SN 2007uy on 2008-01-06
00:31:23 UT, down to the following 3-sigma upper limits: v > 20.2 (808 s
exposure time), b > 21.1 (808 s), u > 20.7 (808 s), uvw1 > 20.8 (1619 s),
uvm2 > 20.7 (2187 s), uvw2 > 21.2 (3234 s).

These magnitudes are on the UVOT photometric system (see Poole et al.,
2007, MNRAS, 383, 627) which in the optical is close to the Johnson UBV
system. They have not been corrected for Galactic extinction of E(B-V) =
0.023 mag (Schlegel et al. 1998, ApJ 500, 525). The UVOT photometry
and colors are similar to the early UVOT phase of SN 2006aj/GRB060218
(e.g., Campana et al. 2006, Nature 442, 1008) and consistent with an
emerging supernova, although other possibilities cannot be ruled out.