The highly energetic expansion of SN 2010bh associated with GRB 100316D
We present the spectroscopic and photometric evolution of the nearby (z = 0.059) spectroscopically confirmed Type Ic supernova, SN2010bh, associated with the soft, long-duration gamma-ray burst (X-ray flash) GRB100316D. Intensive follow-up observations of SN2010bh were performed at the ESO Very Larg...
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2012
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v753_n1_p_Bufano http://hdl.handle.net/20.500.12110/paper_0004637X_v753_n1_p_Bufano |
| Aporte de: |
| Sumario: | We present the spectroscopic and photometric evolution of the nearby (z = 0.059) spectroscopically confirmed Type Ic supernova, SN2010bh, associated with the soft, long-duration gamma-ray burst (X-ray flash) GRB100316D. Intensive follow-up observations of SN2010bh were performed at the ESO Very Large Telescope (VLT) using the X-shooter and FORS2 instruments. Thanks to the detailed temporal coverage and the extended wavelength range (3000-24800Å), we obtained an unprecedentedly rich spectral sequence among the hypernovae, making SN2010bh one of the best studied representatives of this SN class. We find that SN2010bh has a more rapid rise to maximum brightness (8.0 ± 1.0 rest-frame days) and a fainter absolute peak luminosity (L bol ≈ 3 × 10 42 erg s -1 ) than previously observed SN events associated with GRBs. Our estimate of the ejected 56 Ni mass is 0.12 ± 0.02 M o . From the broad spectral features, we measure expansion velocities up to 47,000kms -1 , higher than those of SNe 1998bw (GRB980425) and 2006aj (GRB060218). Helium absorption lines He I λ5876 and He I 1.083 μm, blueshifted by 20,000-30,000kms -1 and 28,000-38,000kms -1 , respectively, may be present in the optical spectra. However, the lack of coverage of the He I 2.058 μm line prevents us from confirming such identifications. The nebular spectrum, taken at 186days after the explosion, shows a broad but faint [O I] emission at 6340Å. The light curve shape and photospheric expansion velocities of SN2010bh suggest that we witnessed a highly energetic explosion with a small ejected mass (E k ≈ 10 52 erg and M ej ≈ 3 M o ). The observed properties of SN2010bh further extend the heterogeneity of the class of GRB SNe. © © 2012. The American Astronomical Society. All rights reserved. |
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