Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/25078
Title: | The multifaceted Type II-L supernova 2014G from pre-maximum to nebular phase | Authors: | Terreran, G. Jerkstrand, A. BENETTI, Stefano Smartt, S. J. Ochner, P. TOMASELLA, Lina Howell, D. A. Morales-Garoffolo, A. Harutyunyan, A. Kankare, E. Arcavi, I. CAPPELLARO, Enrico ELIAS DE LA ROSA, NANCY DEL CARMEN Hosseinzadeh, G. Kangas, T. PASTORELLO, Andrea Tartaglia, L. TURATTO, Massimo Valenti, S. Wiggins, P. Yuan, F. |
Issue Date: | 2016 | Journal: | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | Number: | 462 | Issue: | 1 | First Page: | 137 | Abstract: | We present multiband ultraviolet, optical, and near-infrared photometry, along with visual-wavelength spectroscopy, of supernova (SN) 2014G in the nearby galaxy NGC 3448 (25 Mpc). The early-phase spectra show strong emission lines of the high ionization species He II/N IV/C IV during the first 2-3 d after explosion, traces of a metal-rich circumstellar material (CSM) probably due to pre-explosion mass-loss events. These disappear by day 9 and the spectral evolution then continues matching that of normal Type II SNe. The post-maximum light curve declines at a rate typical of Type II-L class. The extensive photometric coverage tracks the drop from the photospheric stage and constrains the radioactive tail, with a steeper decline rate than that expected from the <SUP>56</SUP>Co decay if γ-rays are fully trapped by the ejecta. We report the appearance of an unusual feature on the blue side of H α after 100 d, which evolves to appear as a flat spectral feature linking H α and the [O I] doublet. This may be due to interaction of the ejecta with a strongly asymmetric, and possibly bipolar CSM. Finally, we report two deep spectra at ∼190 and 340 d after explosion, the latter being arguably one of the latest spectra for a Type II-L SN. By modelling the spectral region around the [Ca II], we find a supersolar Ni/Fe production. The strength of the [O I] λλ6300,6363 doublet, compared with synthetic nebular spectra, suggests a progenitor with a zero-age main-sequence mass between 15 and 19 M<SUB>☉</SUB>. | URI: | http://hdl.handle.net/20.500.12386/25078 | URL: | https://academic.oup.com/mnras/article/462/1/137/2589460 | ISSN: | 0035-8711 | DOI: | 10.1093/mnras/stw1591 | Bibcode ADS: | 2016MNRAS.462..137T | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
SN2014G.pdf | PDF editoriale | 5.14 MB | Adobe PDF | View/Open |
Page view(s)
67
checked on Jul 10, 2024
Download(s)
39
checked on Jul 10, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.