IAU Circulars (IAUCs) - циркуляры МАС - 06/2010

[Tikhon]

11 June 2010
IAU Electronic Telegram No.2319

NOVA IN M31: M31N 2010-05a

Kamil Hornoch, Astronomical Institute, Ondrejov; Rubab Khan, Jonathan
Bird, and Ondrej Pejcha, Department of Astronomy, Ohio State University;
Peter Garnavich, Colin Littlefield, and Nancy Paul, University of Notre
Dame; and Samia Bouzid, Rutgers University, report low-resolution optical
spectroscopy (range 450-670 nm, resolution R = 1600) and optical photometry
of M31N 2010-05a (cf. CBET 2305). Spectra were obtained using the OSMOS
spectrograph and the VPH grism on the 2.4-m Hiltner telescope at MDM
Observatory. Magnitude measurements were obtained from co-added R-band
images taken with the OSMOS spectrograph and imager on the 2.4-m Hiltner
telescope, with the Vatt4k imager on the 1.83-m Vatican Advanced Technology
Telescope, and with the 0.65-m telescope (+ G2CCD-3200) at Ondrejov.
A spectrogram taken by Bird on June 5.47 UT (8.43 days after its first
optical detection by Hornoch et al.) exhibits H-alpha, H-beta, and Fe II
emission lines. The HWZI of H-alpha and H-beta is about 2000 km/s. They
did not see any trace of an He II 468.6-nm line. This suggests that the
object is an "Fe II"-class nova. The following additional R-band magnitudes
were obtained for M31N 2010-05a: June 5.024, 17.2 +/- 0.1 (Hornoch and P.
Hornochova, 0.65-m telescope); 5.468, 17.1 +/- 0.1 (Bird, 2.4-m telescope);
6.038, 17.2 +/- 0.1 (Hornoch and Hornochova); 6.473, 17.1 +/- 0.1 (Bird);
7.464, 17.2 +/- 0.1 (Bird); 8.044, 17.4 +/- 0.25 (Hornoch and Hornochova);
9.036, 17.35 +/- 0.1 (Hornoch); 9.459, 17.18 +/- 0.03 (Garnavich,
Littlefield, Paul, and Bouzid, 1.83-m telescope). The 1.83-m telescope
image also shows M31N 2010-03a (cf. CBETs 2192, 2212) at R = 20.1 +/- 0.2.
The novae M31N 2010-02a (cf. CBETs 2190, 2192, 2212), 2010-03b (cf. CBET
2212), and 2010-04a (cf. CBET 2267) are not present on the same image down to
R magnitudes 20.7, 20.6, and 20.5, respectively.
Correcting their initial report on CBET 2305, Koichi Nishiyama and Fujio
Kabashima note that M31N 2010-05a is located 95" west and 29" north of the
center of M31 (not 9" north, as stated on CBET 2305). They add that the nova
brightened to unfiltered mag 16.5 on June 4.779 UT (same instrumentation
details as given on CBET 2305).

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 11 (CBET 2319) Daniel W. E. Green

[Tikhon]

11 June 2010
IAU Electronic Telegram No.2320

SUPERNOVA 2010ea

V. Shumkov, P. Balanutsa, and E. Gorbovskoy, on behalf of the MASTER
team, reports the discovery of an apparent supernova (mag 17.6) on
MASTER-Net (http://observ.pereplet.ru) unfiltered images taken with the
45-cm Gamelton reflector in Kislovodsk on May 29.973 UT. The new object
is located at R.A. = 12h45m29s.52, Decl. = +53d51'49".2 (equinox 2000.0),
which is 0".3 east and 10".8 south of the center of the apparent host galaxy.
Their reference image, taken with a 40-cm Rigter-Slefogt reflector near
Moscow on 2004 Mar. 11 (same wavelength band), shows nothing at this
position to a limiting magnitude of about 18.5. The discovery image
is posted at http://observ.pereplet.ru/images/SN0106 ... 10_all.jpg.
After posting on the Central Bureau's unconfirmed-objects webpage,
D. D. Balam, Dominion Astrophysical Observatory, National Research Council of
Canada, reports that images (limiting mag about 20.5) taken in twilight with
the 1.82-m Plaskett Telescope on June 8.23 UT show 2010ea at magnitude V =
18.34, with colors B-V = +0.2 and V-R = +0.4 (SDSS DR6 magnitudes were
converted to Kron-Cousins using the conversion formulae of Chonis and Gaskell
2007, A.J. 135, 264), and located 0".2 west and 11".0 south of a galaxy with
Sloan Digital Sky Survey magnitude g = 16.61 and redshift z = 0.03
(designated SDSS J12452954+5352002). Balam adds that there is also a very
faint (g = 21.4, r = 21.5) galaxy (or possibly a not in a spiral arm of the
brighter galaxy) located near, but not at, the source position (SDSS
J12452956+5351470); this fainter "galaxy" or knot is located 0".2 east and
13".2 south of the brighter galaxy (and 0".4 east and 2".2 south of 2010ea).

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 11 (CBET 2320) Daniel W. E. Green

[Tikhon]

12 June 2010
IAU Electronic Telegram No.2321

SUPERNOVA 2010eb IN NGC 488

L. A. G. Monard, Pretoria, South Africa, reports his discovery of an
apparent supernova (magnitude 14.7) on an several unfiltered CCD images taken
on June 12.149 UT at the Bronberg Observatory; it was then confirmed on
pre-discovery images that he had taken on May 26.155, when 2010eb was at
magnitude 14.0. The new object is located at R.A. = 1h21m37s.78, Decl. =
+5d17'39".9 (equinox 2000.0), which is 134" west and 135" north of the galaxy
core of the nearby type-Sb galaxy NGC 488. Nothing is seen at this position
on Digitized Sky Survey images (limiting red mag 20.5), on the previous
image of this galaxy taken at the Bronberg Observatory on 2009 Nov. 26.759
(limiting mag 18.0), or on earlier images by Monard.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 12 (CBET 2321) Daniel W. E. Green

[Tikhon]

13 June 2010
IAU Electronic Telegram No.2322

SUPERNOVA 2010ec IN NGC 655

J. Maza, M. Hamuy, R. Antezana, L. Gonzalez, P. Gonzalez, S. Silva, G.
Folatelli, R. Cartier, F. Forster, and S. Marchi, Universidad de Chile; G.
Pignata and M. Cifuentes, Universidad Andres Bello; B. Conuel, Wesleyan
University; and D. Reichart, K. Ivarsen, J. Haislip, A. Crain, D. Foster,
M. Nysewander, and A. LaCluyze, University of North Carolina at Chapel Hill,
on behalf of the CHASE project, report the discovery of an apparent supernova
(mag approximately 17.1 +/- 0.3) on an unfiltered image taken on June 5.40 UT
with the 0.41-m 'PROMPT 3' telescope located at Cerro Tololo. The new object,
which is also present at mag approximately 17.0 in an image taken on June
8.44, is located at R.A. = 1h41m55s.93 +/- 0".1, Decl. = -13o05'01".6 +/- 0".1
(equinox 2000.0), which is about 11".8 east and 7".4 south of the center of
the galaxy NGC 655. Nothing is visible at this position on archival images
taken on 2009 Oct. 13.17 and Nov. 20.21 (limiting mag 18.5).

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 13 (CBET 2322) Daniel W. E. Green

[Tikhon]

13 June 2010
IAU Electronic Telegram No.2323

SUPERNOVAE 2010cs, 2010ct, 2010du, AND 2010eb

J. M. Silverman, S. B. Cenko, D. Poznanski, and A. V. Filippenko,
University of California, Berkeley, report that inspection of CCD spectra
(range 350-1000 nm), obtained on June 12 UT with the 10-m Keck I telescope
(+ LRIS), shows that 2010cs (CBET 2284) is a type-Ia supernova. Cross-
correlation with a library of supernova spectra using the "SuperNova
IDentification" code of Blondin and Tonry (2007, Ap.J. 666, 1024)
indicates that 2010cs is about one month past maximum brightness. SN 2010ct
(CBET 2285) is a type-II supernova, probably of the IIP subtype and roughly
one month after the explosion; H-alpha exhibits a well-developed P-Cyg
profile; after removal of the host-galaxy recession velocity of 8300 km/s,
determined from narrow emission features, the absorption minimum of the
H-alpha line is found to be blueshifted by about 6400 km/s. SN 2010du (CBET
2308) is also a type-II supernova, probably a type-IIP event roughly one
month after the explosion; its spectrum is very similar to that of SN
2010ct. A CCD spectrum obtained in bright twilight, and only over the
wavelength range 350-560 nm, indicates that 2010eb (CBET 2321) is a
supernova, probably of type Ia and more than 1 month past maximum brightness.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 13 (CBET 2323) Daniel W. E. Green

[Tikhon]

14 June 2010
IAU Electronic Telegram No.2324

SUPERNOVA 2010ed IN UGC 10728

Further to CBET 2308, M. Kandrashoff, S. B. Cenko, W. Li, and A. V.
Filippenko, University of California, report the LOSS discovery of an
apparent supernova on unfiltered KAIT images:

SN 2010 UT R.A. (2000.0) Decl. Mag. Offset
2010ed June 12.43 17 09 24.13 +22 12 48.1 18.7 12".4 W, 2".7 S

Additional KAIT magnitudes for 2010ed in UGC 10728: June 6.44 UT, [19.9;
13.38, 18.8.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 14 (CBET 2324) Daniel W. E. Green

[Tikhon]

16 June 2010
IAU Electronic Telegram No.2325

SUPERNOVA 2010ed IN UGC 10728

P. Challis, R. J. Foley, R. Kirshner, E. Berger, A. Soderberg and G. H.
Marion, Harvard-Smithsonian Center for Astrophysics, report that a CCD
spectrum (range 345-865 nm), obtained on June 16 UT with the 6.5-m MMT
telescope (+ Blue Channel), shows that 2010ed (cf. CBET 2324) is a type-Ia
supernova. The continuum is relatively red, and there is a prominent
(EW = 0.52 nm) Na D absorption component at the redshift of the host galaxy
of cz = 14700 km/s. Cross-correlation with a library of supernova spectra,
using the "SuperNova IDentification" code (SNID; Blondin and Tonry 2007,
Ap.J. 666, 1024), indicates that 2010ed may be similar to the luminous
supernova 1999aa (e.g., Garavini et al. 2004, A.J. 128, 387) near maximum
light. The Si II absorption is blueshifted by 10500 km/s. Given an
apparent magnitude of about 18.7 (from CBET 2324), the distance modulus of
36.55 suggests that M = -17.85, which is quite dim for a luminous type-Ia
supernova. Together with the strong D-line, this suggests a significant
amount of extinction for SN 2010ed.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 16 (CBET 2325) Daniel W. E. Green

[Tikhon]

17 June 2010
IAU Electronic Telegram No.2326

SUPERNOVA 2010ee IN UGC 8652

Further to CBET 2324, M. Kandrashoff, S. B. Cenko, W. Li, and A. V.
Filippenko, University of California, report the LOSS discovery of an
apparent supernova on unfiltered KAIT images:

SN 2010 UT R.A. (2000.0) Decl. Mag. Offset
2010ee June 14.29 13 40 17.99 +26 21 11.9 19.0 0".4 E, 13".1 N

Additional KAIT magnitudes for 2010ee: a co-added image from 2010 Jan.-May,
[20.2; June 15.30 UT, 18.9.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 17 (CBET 2326) Daniel W. E. Green

[Tikhon]

17 June 2010
IAU Electronic Telegram No.2327

SUPERNOVAE 2010ef, 2010eg, AND 2010eh

Further to CBET 2302, J. L. Prieto, Carnegie Observatories; A. J. Drake,
S. G. Djorgovski, A. Mahabal, M. J. Graham, and R. Williams, California
Institute of Technology; M. Catelan, Pontificia Universidad Catolica de
Chile; E. C. Beshore and S. M. Larson, Lunar and Planetary Laboratory,
University of Arizona; and E. Christensen, Gemini Observatory, report the CRTS
discovery of supernovae in unfiltered Catalina Sky Survey (CSS) and Siding
Spring Survey (SSS) images:

SN 2010 UT R.A. (2000.0) Decl. Mag. Offset
2010ef June 5.33 16 28 52.10 +26 22 29.0 19.1 0".7 E, 0".9 S
2010eg June 7.75 22 15 42.56 - 9 20 17.3 18.5 1".6 E, 1".2 N
2010eh June 13.38 20 48 13.54 - 5 48 13.0 17.4 0".3 W, 30".4 N

Further unfiltered CCD magnitudes for 2010ef: May 9.80 UT, [20.2 (SSS); June
8.80, 18.5 (SSS); 10.43, 18.5 (Mt. Lemmon Survey). Further unfiltered CCD
magnitudes for 2010eg: May 24.31, [19.5 (CSS). Further magnitudes for
2010eh: June 5.41, [19.0 (CSS).
J. Prieto, Carnegie Observatories, reports that optical spectra (range
370-930 nm; resolution 0.7 nm) of 2010ef, 2010eg, and 2010eh were obtained
with the APO 3.5-m telescope (+ DIS) on June 15 UT. After cross-correlation
with a library of supernova spectra using SNID (Blondin and Tonry 2007, Ap.J.
666, 1024), the following spectral classifications were obtained: 2010ef is
a normal type-Ia supernova at z = 0.11 (redshift from the supernova spectrum)
around maximum light; 2010eg is a type-Ia supernova at z = 0.09 (redshift
from the supernova spectrum), also around maximum; and 2010eh looks like a
type-Ic supernova at z = 0.020 (redshift of the host galaxy, MCG -01-53-11,
from the Sloan Digital Sky Survey) around maximum, although SNID also
provides relatively good fits with some type-Ib-supernova templates.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 17 (CBET 2327) Daniel W. E. Green

[Tikhon]

17 June 2010
IAU Electronic Telegram No.2328

SUPERNOVAE 2010dq AND 2010dr

P. Challis, R. J. Foley, R. Kirshner, E. Berger, A. Soderberg and G. H.
Marion, Harvard-Smithsonian Center for Astrophysics, report that CCD spectra
(range 345-865 nm), obtained on June 17 UT with the 6.5-m MMT (+ Blue Channel
spectrograph) at Mount Hopkins, show that 2010dq (cf. CBET 2303) is type-Ia
supernova. SN 2010dq shows the prominent Ti II feature associated with
low-luminosity supernovae like SN 1991bg near maximum light (e.g., Filippenko
et al. 1992, A.J. 104, 1543; Leibundgut et al. 1993 A.J. 105, 301). The Si
II absorption is blueshifted by 11350 km/s. Cross-correlation with a library
of supernova spectra, using the "SuperNova IDentification" code (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024), indicates that 2010dq is most
similar to SN 1991bg at three days after maximum brightness.
Observations with the same equipment show that 2010dr (cf. CBET 2304) is
a type-II supernova. The H-alpha and H-beta lines of 2010dr have only broad
triangular emission components. H-alpha has a FWHM of 7500 km/s. The
spectrum is similar to those of SN 1979C (e.g., Panagia et al. 1980, MNRAS
192, 861) and SN 1998S (e.g., Leonard et al. 2000, Ap.J. 536, 239) a few
months past maximum brightness; no narrow component is detected, suggesting
that SN 2010dr is likely of type IIL.

K. Kinugasa, H. Takahashi, and O.Hashimoto, Gunma Astronomical
Observatory (GAO), write that a low-resolution spectrum (range 420-800 nm;
resolution about 500) of 2010dq was obtained on June 16.7 UT with the GAO
1.5-m telescope (+ GLOWS). The spectrum most resembles to that of a typical
type-Ia supernova. Comparison with a library of spectra via the "Supernova
Identification" code (Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that
2010dq is most nearly similar to SN 1992A about 9 days after maximum.
Adopting the NED recession velocity of 5440 km/s for NGC 57 (de Vaucouleurs
et al. 1991, Third Reference Catalogue of Bright Galaxies, ver. 3.9), the
expansion velocity derived from the Si II absorption minimum (rest 635.5 nm)
is about 9500 km/s.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 17 (CBET 2328) Daniel W. E. Green

[Tikhon]

18 June 2010
IAU Electronic Telegram No.2329

SUPERNOVAE 2010ei, 2010ej, AND 2010ek

Further to CBET 2326, M. Kandrashoff, S. B. Cenko, W. Li, and A. V.
Filippenko, University of California, report the LOSS discovery of three
apparent supernovae on unfiltered KAIT images:

SN 2010 UT R.A. (2000.0) Decl. Mag. Offset
2010ei June 12.34 14 54 07.69 +42 32 54.6 17.5 0".2 W, 1".5 N
2010ej June 15.30 14 13 56.74 +31 32 25.1 19.2 2".3 E, 0".5 N
2010ek June 15.48 22 48 40.96 +27 37 11.4 18.8 3".1 E, 30".3 N

Additional KAIT magnitudes for 2010ei in SDSS J145407.71+423253.1: June 6.35
UT, [19.6; 17.31, 17.5. Additional KAIT magnitudes for 2010ej in SDSS
J141356.56+313224.6: a co-added image from 2010 Jan.-May, [20.5; June 16.31,
19.5. Additional KAIT magnitudes for 2010ek in UGC 12191: a co-added image
from 2009 Oct.-Dec., [20.1; 2010 June 16.44, 18.8.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 18 (CBET 2329) Daniel W. E. Green

[Tikhon]

18 June 2010
IAU Electronic Telegram No.2330

SUPERNOVA 2010eb IN NGC 488

Further to CBET 2321 and 2323, D. Milisavljevic, R. Fesen, and J. Parrent,
Dartmouth College, report on low-resolution spectra (range 440-800 nm) of SN
2010eb obtained during morning twilight with the 2.4-m Hiltner telescope (+
CCDS) at the MDM Observatory on June 13.47 UT. Inspection of these spectra
show that 2010eb appears to be a spectroscopically peculiar, sub-luminous
type-Ia supernova. The spectra most closely resemble that of SN 1998bp
(Matheson et al. 2008, A.J. 135, 1598) at approximately two weeks after
maximum light.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 18 (CBET 2330) Daniel W. E. Green

[Tikhon]

19 June 2010
IAU Electronic Telegram No.2331

SUPERNOVAE 2010dx AND 2010ec

S. Valenti and A. Pastorello, Queen's University, Belfast; M. Turatto,
Istituto Nazionale di Astrofisica (INAF), Osservatorio di Catania; and S.
Benetti and F. Bufano, INAF, Osservatorio di Padova, report that a
spectrogram of 2010dx (cf. CBET 2314), obtained on June 18.35 UT with the
European Southern Observatory's New Technology Telescope (+ EFOSC2; range
350-730 nm; resolution 1.9 nm) under less-than-ideal conditions, shows a
strong H_alpha component in emission largely dominating over the absorption.
In addition, lines of Fe II (multiplet 42) are also clearly visible.
Comparison of the observed spectrum with a library of supernova spectra via
the "GELATO" code (Harutyunyan et al. 2008, A.Ap. 488, 383, available at
website URL https://gelato.tng.iac.es/login.cgi) shows strong resemblance to
several type-II supernova at a few weeks after explosion. Assuming a
distance modulus of 34.1, SN 2010dx has an absolute magnitude at discovery of
-17.1. A spectrum of SN 2010ec (cf. CBET 2322) was also obtained on June
18.4 with the same equipment; comparison with a library of supernova spectra
through the "GELATO" code shows strong similarity of SN 2010ec to several
normal type-Ia supernova, such as 1994D and 1994ae, about 3 months past
maximum.

Shortly after the issuing of CBET 2314, L. A. G. Monard reported his
independent discovery of SN 2010dx at magnitude 17.6 on several unfiltered
CCD images taken on June 9.051 UT at his Bronberg Observatory near Pretoria,
South Africa, and confirmed at mag 17.7 on June 9.934. He later reported a
third night at magnitude 17.7 on June 10.150. His measured position for
2010dx is R.A. = 21h15m11s.18, Decl. = -47d13'33".9 (equinox 2000.0), which is
38" east and 20" south of the galaxy core of NGC 7038. He noted that nothing
was visible at this position on his image from May 23.071 (limiting mag 18.8).
Corrigendum. On CBET 2314, line 10, FOR 36".4 east 20".2 south
READ 36".4 east and 20".2 south

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 19 (CBET 2331) Daniel W. E. Green

[Tikhon]

19 June 2010
IAU Electronic Telegram No.2332

TWO APPARENT NOVAE IN M81: M81N 2010-06a AND M81N 2010-06b

Kamil Hornoch, Astronomical Institute, Ondrejov; Peter Garnavich,
Colin Littlefield, and Nancy Paul, University of Notre Dame; and Samia
Bouzid, Rutgers University, report their discovery of two apparent novae in
the galaxy M81 on a co-added 1200-s R-band CCD frame taken by Garnavich,
Littlefield, Paul, and Bouzid with the Vatt4k imager on the 1.83-m Vatican
Advanced Technology Telescope on June 11.164 UT. The new objects are visible
on single 200-s images used for the co-added image. Narrow-band H_alpha CCD
frames taken by Daniel J. Hurley, University College, Cork; and Hannu
Parviainen and Hans J. Deeg, Instituto de Astrofisica de Canarias and
Universidad de La Laguna, with the 2.54-m Isaac Newton Telescope (+ WFC) at
La Palma on June 14.893 and 15.920 confirmed the presence of both new
objects, which are not present on numerous archive images from the 2.54-m
Isaac Newton Telescope, the 4.2-m William Herschel Telescope, the 4-m
Mayall telescope, and the 8.2-m Subaru telescope, down to limiting
magnitudes as faint as Sloan r' = 23.3, R = 23.4, V = 23.8, and [H_alpha] =
22.3.
M81N 2010-06a is located at R.A. = 9h55m48s.85, Decl. = +69o03'26".4
(equinox 2000.0), which is 84".0 east and 28".7 south of the center of M81.
Available R-band and [H_alpha] magnitudes for M81N 2010-06a, measured by
Hornoch: June 11.164 UT, R = 21.2 +/- 0.15 (Garnavich, Littlefield, Paul,
and Bouzid, 1.83-m telescope); 14.893, [H_alpha] = 21.1 +/- 0.2 (Hurley,
Parviainen, and Deeg, 2.54-m telescope); 15.920, [H_alpha] = 21.3 +/- 0.15
(Hurley, Parviainen, and Deeg).
M81N 2010-06b is located at R.A. = 9h55m19s.39, Decl. = +69o06'20".6
(equinox 2000.0), which is 73".8 west and 145".5 north of the center of M81.
Available magnitudes for M81N 2010-06b: June 11.164, R = 21.9 +/- 0.2
(Garnavich, Littlefield, Paul, and Bouzid); 14.893, [H_alpha] = 20.0 +/- 0.1
(Hurley, Parviainen, and Deeg; 15.920, [H_alpha] = 19.9 +/- 0.1 (Hurley,
Parviainen, and Deeg).

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 19 (CBET 2332) Daniel W. E. Green

[Tikhon]

20 June 2010
IAU Electronic Telegram No.2333

SUPERNOVAE 2010ee, 2010ei, AND 2010ek

J. M. Silverman, C. V. Griffith, M. T. Kandrashoff, and A. V. Filippenko,
University of California, Berkeley, report that inspection of a low-signal-to-
noise-ratio CCD spectrum (range 340-1000 nm), obtained on June 18 UT with the
3-m Shane reflector (+ Kast) at Lick Observatory, shows that 2010ee (CBET
2326) is a type-II supernova; H-alpha has a well-developed P-Cyg profile.
After removal of the host-galaxy recession velocity of 8500 km/s, determined
from narrow emission features, the absorption minimum of the H-alpha line is
found to be blueshifted by about 5500 km/s.
SN 2010ei (CBET 2329) is a type-II supernova, probably of subtype IIb,
1-2 weeks after the explosion. After removal of the host-galaxy recession
velocity of 5600 km/s, determined from narrow emission features, the
absorption minimum of the H-alpha line is found to be blueshifted by about
16300 km/s. However, this may be a slight overestimate if H-alpha has some
residual blending with Si II 635.5 nm, which was seen at a similar velocity
in the type-IIb supernova 2003bg at one week past explosion (Hamuy et al.
2009, Ap.J. 703, 1612).
SN 2010ek (CBET 2329) is a type-IIb supernova a few days before maximum
brightness. Cross-correlation with a library of supernova spectra using the
"SuperNova IDentification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) indicates that 2010ek is 4 days before maximum. After removal of the
host-galaxy recession velocity of 9400 km/s, determined from narrow emission
features, the absorption minimum of the H-alpha line is found to be
blueshifted by about 11500 km/s.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 20 (CBET 2333) Daniel W. E. Green

[Tikhon]

20 June 2010
IAU Electronic Telegram No.2334

SUPERNOVA 2010el IN NGC 1566

L. A. G. Monard, Pretoria, South Africa, reports his discovery of an
apprent supernova (magnitude 16.8) on unfiltered CCD images taken at Bronberg
on June 19.142 UT. The new object is located at R.A. = 4h19m58s.83, Decl. =
-54d56'38".5 (equinox 2000.00, which is 13" west and 22" south of the galaxy
core of the nearby galaxy NGC 1566. Nothing is visible at this position in
Digitized Sky Survey images (limiting red mag 20.5). Additional magnitudes
for 2010el from Monard's images: June 3.140, [18.0; 20.144, 16.5.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 20 (CBET 2334) Daniel W. E. Green

[Tikhon]

20 June 2010
IAU Electronic Telegram No.2335

SUPERNOVA 2010em IN UGC 12237

Further to CBET 2329, M. Kandrashoff, S. B. Cenko, W. Li, and A. V.
Filippenko, University of California, report the LOSS discovery of an
apparent supernova on unfiltered KAIT images:

SN 2010 UT R.A. (2000.0) Decl. Mag. Offset
2010em June 18.47 22 54 20.33 +11 46 54.7 18.4 9".6 E, 2".1 S

Additional KAIT magnitudes for 2010em: a co-added image from 2009 Oct.-Dec.,
[19.7; 2010 June 19.47, 18.2.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 20 (CBET 2335) Daniel W. E. Green

[Tikhon]

21 June 2010
IAU Electronic Telegram No.2336

SUPERNOVA 2010dc IN IC 4854

S. Valenti and A. Pastorello, Queen's University, Belfast; M. Turatto,
Istituto Nazionale di Astrofisica (INAF), Osservatorio di Catania; and S.
Benetti and F. Bufano, INAF, Osservatorio di Padova, on behalf of a larger
collaboration, report that a low-signal-to-noise spectrogram of 2010dc (cf.
CBET 2291), obtained on June 19.4 UT with the European Southern Observatory's
New Technology Telescope (+ EFOSC2; range 350-730 nm; resolution 1.9 nm)
under poor sky conditions, is that of a type-Ib/c supernova, 2-3 weeks after
maximum. Comparison of the observed spectrum with a library of supernova
spectra via the "GELATO" code (Harutyunyan et al. 2008, A.Ap. 488, 383;
available at website URL https://gelato.tng.iac.es/login.cgi) shows strong
resemblance to that of SN 2007gr (Valenti et al. 2008, Ap.J. 673, 155) at 17
days after B-band maximum.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 21 (CBET 2336) Daniel W. E. Green

[Tikhon]

23 June 2010
IAU Electronic Telegram No.2337

SUPERNOVA 2010el IN NGC 1566

M. S. Bessell and B. P. Schmidt, Australian National University (ANU),
report that a spectrogram (range 350-950 nm) of 2010el (cf. CBET 2334),
obtained on June 23.80 UT with the 2.3-m ANU telescope (+ Wide Field Imaging
Spectrograph), shows a relatively red continuum populated with low-velocity
lines, including Si II 635.5-nm, and Ca H and K and the Ca infrared triplet.
Ryan Foley, Harvard-Smithsonian Center for Astrophysics, notes that the
object is remarkably similar to the low-energy peculiar type-Ia supernova
2008ha at one day before maximum light (Foley et al. 2009, A.J. 138, 37).

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 23 (CBET 2337) Daniel W. E. Green

[Tikhon]

26 June 2010
IAU Electronic Telegram No.2338

NOVAE IN M81: M81N 2010-06a, M81N 2010-06b, M81N 2010-06c, M81N 2010-06d

Kamil Hornoch, Astronomical Institute, Ondrejov; Daniel J. Hurley,
University College, Cork; and Hannu Parviainen and Hans J. Deeg, Instituto
de Astrofisica de Canarias and Universidad de La Laguna, report their
discovery of two additional apparent novae in the galaxy M81 on a co-added
900-s narrow-band H_alpha CCD frame taken by Hurley, Parviainen, and Deeg
with the 2.54-m Isaac Newton Telescope (+ WFC) at La Palma on
June 14.893 UT. The new objects are visible on single 300-s images
used for the co-added image. Additional narrow-band H_alpha CCD
frames taken by Hurley, Parviainen, and Deeg, with the same instrumentation
on June 15.920 confirmed the presence of both new objects, which are not
present on numerous archive images from the 2.54-m Isaac Newton Telescope,
the 4.2-m William Herschel Telescope, the 4-m Mayall telescope, the 8.2-m
Subaru telescope, and the 8.1-m Gemini North telescope, down to limiting
magnitudes as faint as Sloan r' = 22.4, R = 22.6, V = 22.5, and
[H_alpha] = 21.6.
M81N 2010-06c is located at R.A. = 9h55m31s.00, Decl. = +69o04'03".3
(equinox 2000.0), which is 11".6 west and 8".2 north of the center of M81.
Available R-band and [H_alpha] magnitudes for M81N 2010-06c, measured by
Hornoch: June 11.164 UT, [21.0 (P. Garnavich, C. Littlefield, N. Paul, and
S. Bouzid, 1.83-m Vatican Advanced Technology Telescope + R filter);
14.893, [H_alpha] = 19.9 +/- 0.2 (Hurley, Parviainen, and Deeg, 2.54-m
telescope); 15.920, [H_alpha] = 19.6 +/- 0.2 (Hurley, Parviainen, and Deeg).
M81N 2010-06d is located at R.A. = 9h55m34s.96, Decl. = +69o03'51".5
(equinox 2000.0), which is 9".6 east and 3".6 south of the center of M81.
Available magnitudes for M81N 2010-06d: June 11.164, [20.9 (Garnavich,
Littlefield, Paul, and Bouzid, 1.83-m telescope + R filter); 14.893,
[H_alpha] = 20.1 +/- 0.3 (Hurley, Parviainen, and Deeg); 15.920, [H_alpha]
= 20.0 +/- 0.2 (Hurley, Parviainen, and Deeg).

Julie Nantais and John Huchra, Harvard-Smithsonian Center for
Astrophysics, examined the locations of the recently discovered novae M81N
2010-06a and M81N 2010-06b (as reported by Hornoch et al. on CBET 2332) in
deep Hubble Space Telescope Advanced Camera for Surveys imaging in the
bands B, V, and I. The Hubble images date between September 2004 and
December 2006. No visible progenitors are found for these novae to
magnitudes B about 25.7, V about 24.7, and I about 24.2.

NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
superseded by text appearing later in the printed IAU Circulars.

2010 June 26 (CBET 2338) Daniel W. E. Green