Browsing by Author "Thoene, C. C."

Now showing 1 - 4 of 4
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    A young stellar environment for the superluminous supernova PTF12dam
    (OXFORD UNIV PRESS, 2015) Thoene, C. C.; Postigo, A. de Ugarte; Garcia Benito, R.; Leloudas, G.; Schulze, S.; Amorin, R.
    The progenitors of superluminous supernovae (SLSNe) are still a mystery. Hydrogen-poor SLSN hosts are young, highly star-forming dwarf galaxies and the majority belongs to the class of 'extreme emission line galaxies'. Here we present a resolved long-slit study of the host of the hydrogen-poor SLSN PTF12dam probing the kiloparsec environment of the SN site to determine the age of the progenitor. The SN occurred in a star-forming region in the head of a 'tadpole' galaxy with largely uniform properties. The galaxy experienced a recent starburst superimposed on an underlying old stellar population (SP). We determine a very young SP at the SN site of similar to 3 Myr and a metallicity of 12+log(O/H)=8.0 but do not observe any Wolf-Rayet features. The progenitor of PTF12dam was likely a massive star of >60 M-circle dot and one of the first stars exploding as an SN in the most recent starburst episode.
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    GRB 140606B/iPTF14bfu: detection of shock-breakout emission from a cosmological gamma-ray burst?
    (OXFORD UNIV PRESS, 2015) Cano, Zach; de Ugarte Postigo, A.; Perley, D.; Kruehler, T.; Margutti, R.; Friis, M.; Malesani, D.; Jakobsson, P.; Fynbo, J. P. U.; Gorosabel, J.; Hjorth, J.; Sanchez Ramirez, R.; Schulze, S.; Tanvir, N. R.; Thoene, C. C.; Xu, D.
    We present optical and near-infrared photometry of GRB 140606B (z = 0.384), and optical photometry and spectroscopy of its associated supernova (SN). The results of our modelling indicate that the bolometric properties of the SN (M-Ni = 0.4 +/- 0.2 M-circle dot, M-ej = 5 +/- 2 M-circle dot, and E-K = 2 +/- 1 x 10(52) erg) are fully consistent with the statistical averages determined for other gamma-ray burst (GRB)-SNe. However, in terms of its gamma-ray emission, GRB 140606B is an outlier of the Amati relation, and occupies the same region as low luminosity (ll) and short GRBs. The gamma-ray emission in llGRBs is thought to arise in some or all events from a shock breakout (SBO), rather than from a jet. The measured peak photon energy (E-p approximate to 800 keV) is close to that expected for. -rays created by an SBO (greater than or similar to 1 MeV). Moreover, based on its position in the M-V,M- (p)- L-iso,L-gamma plane and the E-K-Gamma eta plane, GRB 140606B has properties similar to both SBO-GRBs and jetted-GRBs. Additionally, we searched for correlations between the isotropic gamma-ray emission and the bolometric properties of a sample of GRB-SNe, finding that no statistically significant correlation is present. The average kinetic energy of the sample is (E) over bar (K) = 2.1 x 10(52) erg. All of the GRB-SNe in our sample, with the exception of SN 2006aj, are within this range, which has implications for the total energy budget available to power both the relativistic and non-relativistic components in a GRB-SN event.
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    The optical identification of events with poorly defined locations: the case of the Fermi GBM GRB 140801A
    (OXFORD UNIV PRESS, 2016) Lipunov, V. M.; Gorosabel, J.; Pruzhinskaya, M. V.; de Ugarte Postigo, A.; Pelassa, V.; Tsvetkova, A. E.; Sokolov, I. V.; Kann, D. A.; Xu, Dong; Gorbovskoy, E. S.; Krushinski, V. V.; Kornilov, V. G.; Balanutsa, P. V.; Boronina, S. V.; Budnev, N. M.; Cano, Z.; Castro Tirado, A. J.; Chazov, V. V.; Connaughton, V.; Delvaux, C.; Frederiks, D. D.; Fynbo, J. F. U.; Gabovich, A. V.; Goldstein, A.; Greiner, J.; Gress, O. A.; Ivanov, K. I.; Jakobsson, P.; Klose, S.; Knust, F.; Komarova, V. N.; Konstantinov, E.; Krylov, A. V.; Kuvshinov, D. A.; Kuznetsov, A. S.; Lipunova, G. V.; Moskvitin, A. S.; Pal'shin, V. D.; Pandey, S. B.; Poleshchuk, V. A.; Schmidl, S.; Sergienko, Yu. P.; Sinyakov, E. V.; Schulze, S.; Sokolov, V. V.; Sokolova, T. N.; Sparre, M.; Thoene, C. C.; Tlatov, A. G.; Tyurina, N. V.; Ulanov, M. V.; Yazev, S. A.; Yurkov, V. V.
    We report the early discovery of the optical afterglow of gamma-ray burst (GRB) 140801A in the 137 deg(2) 3-sigma error-box of the Fermi Gamma-ray Burst Monitor (GBM). MASTER is the only observatory that automatically reacts to all Fermi alerts. GRB 140801A is one of the few GRBs whose optical counterpart was discovered solely from its GBM localization. The optical afterglow of GRB 140801A was found by MASTER Global Robotic Net 53 s after receiving the alert, making it the fastest optical detection of a GRB from a GBM error-box. Spectroscopy obtained with the 10.4-m Gran Telescopio Canarias and the 6-m Big Telescope Alt-azimuth of the Special Astrophysical Observatory of the Russian Academy of Sciences reveals a redshift of z = 1.32. We performed optical and near-infrared photometry of GRB 140801A using different telescopes with apertures ranging from 0.4 to 10.4 m. GRB 140801A is a typical burst in many ways. The rest-frame bolometric isotropic energy release and peak energy of the burst are E-iso = 5.54(-0.24)(+0.26) x 10(52) erg and E-p,E- rest similar or equal to 280 keV, respectively, which is consistent with the Amati relation. The absence of a jet break in the optical light curve provides a lower limit on the half-opening angle of the jet theta = 6 degrees.1. The observed E-peak is consistent with the limit derived from the Ghirlanda relation. The joint Fermi GBM and Konus-Wind analysis show that GRB 140801A could belong to the class of intermediate duration. The rapid detection of the optical counterpart of GRB 140801A is especially important regarding the upcoming experiments with large coordinate error-box areas.
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    The warm, the excited, and the molecular gas: GRB 121024A shining through its star-forming galaxy
    (OXFORD UNIV PRESS, 2015) Friis, M.; De Cia, A.; Kruehler, T.; Fynbo, J. P. U.; Ledoux, C.; Vreeswijk, P. M.; Watson, D. J.; Malesani, D.; Gorosabel, J.; Starling, R. L. C.; Jakobsson, P.; Varela, K.; Wiersema, K.; Drachmann, A. P.; Trotter, A.; Thoene, C. C.; de Ugarte Postigo, A.; D'Elia, V.; Elliott, J.; Maturi, M.; Goldoni, P.; Greiner, J.; Haislip, J.; Kaper, L.; Knust, F.; LaCluyze, A.; Milvang Jensen, B.; Reichart, D.; Schulze, S.; Sudilovsky, V.; Tanvir, N.; Vergani, S. D.
    We present the first reported case of the simultaneous metallicity determination of a gamma- ray burst (GRB) host galaxy, from both afterglow absorption lines as well as strong emission- line diagnostics. Using spectroscopic and imaging observations of the afterglow and host of the long- duration Swift GRB 121024A at z = 2.30, we give one of the most complete views of a GRB host/ environment to date. We observe a strong damped Lya absorber (DLA) with a hydrogen column density of log N(H i) = 21.88 +/- 0.10, H-2 absorption in the Lyman- Werner bands (molecular fraction of log(f) approximate to- 1.4; fourth solid detection of molecular hydrogen in a GRB- DLA), the nebular emission lines H alpha, H beta, [OII], [O III] and [N II], as well as metal absorption lines. We find aGRB host galaxy that is highly star forming (SFR similar to 40M circle dot yr(-1)), with a dust- corrected metallicity along the line of sight of [Zn/ H](corr) =- 0.6 +/- 0.2 ([O/H]similar to- 0.3 from emission lines), and a depletion factor [Zn/ Fe] = 0.85 +/- 0.04. The molecular gas is separated by 400 km s(-1) (and 1-3 kpc) from the gas that is photoexcited by the GRB. This implies a fairly massive host, in agreement with the derived stellar mass of log(M*/M-circle dot) = 9.9(-0.3)(+0.2). We dissect the host galaxy by characterizing its molecular component, the excited gas, and the line- emitting star- forming regions. The extinction curve for the line of sight is found to be unusually flat (R-V similar to 15). We discuss the possibility of an anomalous grain size distributions. We furthermore discuss the different metallicity determinations from both absorption and emission lines, which gives consistent results for the line of sight to GRB 121024A.