2014ds (= PSN J08111645+2510474), discovered 2014/10/11.939. Found in NGC 2536 at R.A. = 08h11m16s.45, Decl. = +25°10'47".4.
Located 6".0 east and 1".7 north of the center of NGC 2536
Mag 16.6:10/25 (16.3:10/11), Type IIb (z=0.0137)

Image

Light curve

Electronic Telegram No. 4010

Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director: Daniel W. E. Green; Hoffman Lab 209; Harvard University;
20 Oxford St.; Cambridge, MA 02138; U.S.A.
e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network

SUPERNOVA 2014ds IN NGC 2536 = PSN J08111645+2510474
Z.-j. Xu (Nanjing, Jiangsu, China) and X. Gao (Urumqi, Xinjiang, China) report the discovery of an apparent supernova (mag approximately 16.3) on one 40-s unfiltered CCD survey image (limiting mag about 18.0) taken by Gao in the course of the Xingming Sky Survey around Oct. 11.939 UT using a 35.6-cm Celestron C14 Schmidt-Cassegrain telescope at Mt. Nanshan. The new object is
approximately located at R.A. = 8h11m16s.45, Decl. = +25d10'47".4 (equinox 2000.0), which is about 6".0 east and 1".7 north of the center of NGC 2536. Nothing is visible at this position on archival images taken on Mar. 4 (limiting mag 18.5) and Mar. 31 (limiting mag 18.4) or on a Digitized Sky Survey image from 1989 Jan. 10 (limiting mag about 19.9). Images were posted at website URL http://www.xjltp.com/XOSS/XM68ZX/XM68ZX.htm. The variable was designated PSN J08111645+2510474 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2014ds based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2014ds: 2014 Oct. 12.376, 16.5 (J. Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope + STXL-6303 camera at the New Mexico Skies observatory near Mayhill, NM, U.S.A.; position end figures 16s.48, 46".7; image posted at website URL https://www.flickr.com/photos/43846774@N02/15338033047/); 12.93, 16.1 (Xu and Gao; position end figures 16s.47, 47".3; image posted at URL http://njzhijian.lamost.org/Supernova/PSNJ08111645+2510474-1012.jpg).

J.-j. Zhang, Yunnan Astronimical Observatory (YNAO); and X.-f. Wang, Tsinghua University, report on an optical spectrogram (range 360-890 nm) of PSN J08111645+2510474 = SN 2014ds that was obtained on Oct. 23.8 UT with the 2.4-m telescope (+ YFOSC) at the LiJiang Gaomeigu Station of YNAO. The spectrum is consistent with a classification of type-IIb supernova, with Fe
II, Ca II, O I, and prominent H and He I features. A more narrow H-alpha emission is found to sit on top of the broad component, which is perhaps due to the interaction of supernova ejecta with the circumstellar materials. Cross-correlation with a library of supernova spectra using the comparison tool "Gelato" (Harutyunyan et al. 2008, A.Ap. 488, 383) shows that 2014ds has a good match with SN 2008ax at a few days before maximum light. After removing a recession velocity of 4142 km/s for the host galaxy, NGC 2536 (from de Vaucouleurs 1991, RC3.9), they measure a velocity of the H-alpha absorption to be about 12600 km/s.

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

(C) Copyright 2014 CBAT
2014 October 30 (CBET 4010) Daniel W. E. Green

2014av (= PSN J09002002+5229280), discovered 2014/04/16.84. Found in UGC 4713 at R.A. = 09h00m20s.02, Decl. = +52°29'28".0.
Located 2".7 west and 11".2 south of the center of UGC 4713
Mag 17.3:5/4 (16.2:4/19), Type Ibn (z=0.030154)

Image

Light curve

Electronic Telegram No. 3865

Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director: Daniel W. E. Green; Hoffman Lab 209; Harvard University;
20 Oxford St.; Cambridge, MA 02138; U.S.A.
e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network

SUPERNOVA 2014av IN UGC 4713 = PSN J09002002+5229280
Zhijian Xu, Nanjing, Jiangsu, China; and Xing Gao, Urumqi, Xinjiang, China, report the discovery of a possible supernova (mag approximately 16.2) on several 40-s survey images (limiting mag about 19.0) taken by Xing Gao in the course of the Xingming Sky Survey around Apr. 19.717 UT using a Celestron C14 Schmidt-Cassegrain telescope at Mt. Nanshan. The new object is located
approximately at R.A. = 9h00m20s.02, Decl. = +52d29'28".0 (equinox 2000.0), which is about 2".7 west and 11".2 south of the center of UGC 4713. Nothing is visible at this position on a Digitized Sky Survey image from 1991 Feb. 9 (limiting mag about 19.5). The images have been posted at the following website URL: http://www.xjltp.com/XOSS/XM67ZX/XM67ZX.htm. The variable was designated PSN J09002002+5229280 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2014av based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2014av: 2014 Mar. 22, [18.5 (Xu and Gao); 26, [19.0 (Xu and Gao); Apr. 16.84, 17.6 (F. Ciabattari and E. Mazzoni, Borgo a Mozzano, Italy; 0.5-m Newtonian telescope + FLI Proline 4710 camera in the course of the Italian Supernovae Search Project; pre-discovery; limiting magnitude 19.5; position end figures 20s.4, 29".2; image posted at https://www.flickr.com/photos/snimages/13934647542/); 19.942, 16.5 (Federica Luppi and Luca Buzzi, Varese, Italy; 0.60-m f/4.6 reflector; position end figures 19s.99, 27".9); 21.783, 16.1 (G. Masi, F. Nocentini, and P. Schmeer; remotely using a 43-cm telescope near Ceccano, Italy; position end figures 19s.99, 27".7); 24.640, 16.2 (Xu and Gao; image posted at URL http://njzhijian.lamost.org/PSN%20J09002002+5229280-0424.jpg).

J.-J. Zhang, Yunnan Astronimical Observatory (YNAO); and X.-F. Wang, Tsinghua University, report on an optical spectrogram (range 350-890 nm) of PSN J09002002+5229280 = SN 2014av that was obtained on Apr. 23.65 UT with the 2.4-m telescope (+ YFOSC) at the LiJiang Gaomeigu Station of YNAO. The spectrum is blue and shows P-Cyg profiles of He I lines, with the FWHM velocity of He I 587.6-nm being estimated as about 1500 km/s. The strong emission feature at 385.0-400.0 nm might be attributed to the blend of He I, Mg II, and Ca II lines. A comparison with the spectra of other supernovae shows that of 2014av to be very similar to a transitional type-Ibn supernova such as 2006jc (Pastorello et al. 2007, Nature 389, 131).

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

(C) Copyright 2014 CBAT
2014 May 7 (CBET 3865) Daniel W. E. Green

2014ak (= PSN J07484410+5436405) (= PS1-14xl), discovered 2014/03/26.69. Found in NGC 2446 at R.A. = 07h48m44s.10, Decl. = +54°36'40".5.
Located 54".8 east and 2".4 south of the center of NGC 2446
Mag 17.5:5/4 (16.3:4/1), Type Ia (z=0.018906)

Image

Light curve

Electronic Telegram No. 3845

Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director: Daniel W. E. Green; Hoffman Lab 209; Harvard University;
20 Oxford St.; Cambridge, MA 02138; U.S.A.
e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network

SUPERNOVA 2014ak IN NGC 2446 = PSN J07484410+5436405
Zhijian Xu, Nanjing, Jiangsu, China; and Xing Gao, Urumqi, Xinjiang, China, report the discovery of an apparent supernova (mag approximately 17.9) on several unfiltered 40-s CCD survey images (limiting mag about 19.5) taken by Xing Gao in the course of the Xingming Sky Survey around Mar. 26.690 UT using a 35.6-cm Celestron C14 Schmidt-Cassegrain telescope at Mt. Nanshan. The new object is approximately located at R.A. = 7h48m44s.10, Decl. = +54d36'40".5 (equinox 2000.0), which is about 54".8 east and 2".4 south of the center of NGC 2446. Nothing is visible at this position on a Digitized Sky Survey image from 1995 Feb. 25 (limiting mag about 19.5). The variable was designated PSN J07484410+5436405 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2014ak based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2014ak: 2014 Mar. 3, [19.0 (Xu and Gao); 21, [18.5 (Xu and Gao); 27.129, 18.2 (J. Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope at the New Mexico Skies observatory near Mayhill, NM, U.S.A.; image posted at website URL https://www.flickr.com/photos/43846774@N02/13464892014/); 28.075, 17.6 (Federica Luppi and Luca Buzzi, Varese, Italy; 0.60-m f/4.6 reflector; position end figures 44s.05, 40".5; reference stars from PPMXL catalogue; image posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_N2446.jpg); 28.733, 17.0 (Xu and Gao; image can be viewed via URL http://tinyurl.com/q2aqzy9); 28.827, 17.1 (Gianluca Masi, Francesca Nocentini, and Patrick Schmeer; remotely using a 43-cm telescope near Ceccano, Italy; position end figures 44s.02, 40".5); 28.867, V = 17.5 (Massimiliano Martignoni, Magnago, Italy; 25-cm f/10 reflector; position end figures 43s.97, 40".8; PPMXL reference stars); Apr. 2.130, 16.6 (Brimacombe; position end figures 44s.07, 40".7; image posted at URL https://www.flickr.com/photos/43846774@N02/13618556293/).

G. Terreran, L. Tomasella, S. Benetti, E. Cappellaro, N. Elias-Rosa, P. Ochner, A. Pastorello, and M. Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, report that an optical spectrogram of PSN J07484410+5436405 = SN 2014ak (range 340-820 nm; resolution 1.3 nm), obtained on Mar. 31.02 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC), shows it to be a type-Ia supernova. Adopting for the host galaxy (NGC 2446) a radial velocity of 5668 km/s (Theureau et al. 1998, A.Ap. Suppl. 130, 333; via NED), a good match is found with several type-Ia supernovae around few days before B-band maximum light. An expansion velocity of about 11800 km/s is derived from the minimum of the Si II 635-nm line. The Asiago classification spectra are posted at URL http://sngroup.oapd.inaf.it; classification was made via GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666, 1024).

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

(C) Copyright 2014 CBAT
2014 April 5 (CBET 3845) Daniel W. E. Green