Radio Detection of SN 2014bc in NGC 4258 with eMERLIN
ATel #6273; M. Argo (JBCA, Manchester), M. Perez-Torres (IAA-CSIC and CEFCA, Spain), A. Alberdi (IAA-CSIC), R. Beswick (JBCA, Manchester), J. Conway (OSO, Onsala), N. Elias-Rosa (INAF, Padova), R. Herrero-Illana (IAA-CSIC, Granada), R. Kotak (Queen's Univ. Belfast), P. Lundqvist (Stockholms Observatory), S. Mattila (Univ. of Turku), J. Marcaide (Univ. de Valencia), T. Muxlow (JBCA, Manchester), I. Marti-Vidal (OSO, Onsala), N. Ramirez-Olivencia (IAA-CSIC, Granada), C. Romero-Canizales (IA-PUC/MAS, Chile), C. Stockdale (Marquette University), E. Varenius (OSO, Onsala).
on 26 Jun 2014; 06:16 UT
Credential Certification: Miguel A. Perez-Torres (torres@iaa.es)
(Note: the following report supersedes the information on ATel 6270.)
We report the first detection at radio wavelengths of the type II
SN 2014bc, using the electronic Multi-Element Radio Linked
Interferometer Network (eMERLIN). SN 2014bc was discovered
near (~100 pc) the core of NGC4258
(Messier 106; D=7.6 Mpc) by Smartt et al. (ATel #6156),
using Pan-STARRS1 images taken on 2014 May 19.25 UT.
KAIT unfiltered imaging by Zheng and Fillipenko (ATel #6159) showed the
light curve to be consistent with a Type II-P SN. Ochner et al. (CBET
3877) found a good match of a spectrum of SN 2014bc taken on May 21.82
UT with a spectrum of the Type II-P SN 1986I at about 50 days after discovery.
We observed SN 2014bc at a frequency of 1.51 GHz on 2014 May 23
with eMERLIN, using a total bandwidth of 512 MHz. The resulting
synthesized Gaussian beam was of (0.15 x 0.13) sq. arcseconds. We
centered our observations at the position of the optical discovery
(RA(J2000.0)=12:18:57.71 and DEC(J2000.0)=47:18:11.3) and imaged a
(113 x 113) sq. arcsecond region. We detected SN 2014bc with a peak
flux density of 1.165 mJy/b at the following position:
RA(J2000.0)=12:18:57.5034; DEC(J2000.0)=47:18:11.286. The off-source
r.m.s. of the image was of 0.035 mJy/b. The above radio brightness
corresponds to a monochromatic 1.51 GHz luminosity of (8.00 +/-
0.25)*1e25 erg/s/Hz. This value is typical of Type II-P SNe close to
its peak radio luminosity (see, e.g. Fig. 4 in Romero-Canizales et. al 2014, MNRAS,
440, 1067). Further observations of this nearby SN at radio and other
wavelengths are planned.
We thank the eMERLIN staff for supporting our ToO program on
nearby core-collapse supernovae (Project code CY1204; PI:
Perez-Torres).
