TY - JOUR
T1 - Complexity in the light curves and spectra of slow-evolving superluminous supernovae
AU - Inserra, C.
AU - Nicholl, M.
AU - Chen, T. -W.
AU - Jerkstrand, A.
AU - Smartt, S. J.
AU - Kruehler, T.
AU - Anderson, J. P.
AU - Baltay, C.
AU - Della Valle, Valle, M.
AU - Fraser, M.
AU - Gal-Yam, Avishay
AU - Galbany, L.
AU - Kankare, E.
AU - Maguire, K.
AU - Rabinowitz, D.
AU - Smith, K.
AU - Valenti, S.
AU - Young, D. R.
N1 - ESO [188.D-3003, 191.D-0935, 197.D-1075]; X-Shooter programmes [093.D-0229, 092.D-0555]; European Research Council under the European Union [291222]; STFC [ST/I001123/1, ST/L000709/1]; Munich Institute for Astro- and Particle Physics (MIAPP) of the DFG cluster of excellence 'Origin and Structure of the Universe'; Royal Society - Science Foundation Ireland University Research Fellowship; STFC through an Ernest Rutherford Fellowship; Sofia Kovalevskaja Award from the Alexander von Humboldt Foundation of Germany; UK Science and Technology Facilities Council; Max Planck Institute for Astronomy, Heidelberg; Max Planck Institute for Extraterrestrial Physics, Garching; Johns Hopkins University; Durham University; University of Edinburgh; Queen's University Belfast; Harvard-Smithsonian Center for Astrophysics; Las Cumbres Observatory Global Telescope Network Incorporated; National Central University of Taiwan; Space Telescope Science Institute; National Aeronautics and Space Administration [NNX08AR22G]; National Science Foundation [AST-1238877]; University of Maryland; Eotvos Lorand University (ELTE); Los Alamos National LaboratoryCI thanks Ragnhild Lunnan for sharing the data of PS1-14bj and Stuart Sim for stimulating discussions. This work is based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile as part of PESSTO (the Public ESO Spectroscopic Survey for Transient Objects Survey) ESO programme 188.D-3003, 191.D-0935, 197.D-1075 and the X-Shooter programmes 093.D-0229, 092.D-0555. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no [291222]. SJS acknowledges funding from STFC grants ST/I001123/1 and ST/L000709/1. CI thanks the organizers and participants of the Munich Institute for Astro- and Particle Physics (MIAPP) workshop 'Supernovae: The Outliers' for stimulating CI thanks Ragnhild Lunnan for sharing the data of PS1-14bj and Stuart Sim for stimulating discussions. This work is based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile as part of PESSTO (the Public ESO Spectroscopic Survey for Transient Objects Survey) ESO programme 188.D-3003, 191.D-0935, 197.D-1075 and the X-Shooter programmes 093.D-0229, 092.D-0555. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no [291222]. SJS acknowledges funding from STFC grants ST/I001123/1 and ST/L000709/1. CI thanks the organizers and participants of the Munich Institute for Astro- and Particle Physics (MIAPP) workshop 'Supernovae: The Outliers' for stimulating discussions. This research was supported by the Munich Institute for Astro- and Particle Physics (MIAPP) of the DFG cluster of excellence 'Origin and Structure of the Universe'. MF acknowledges the support of a Royal Society - Science Foundation Ireland University Research Fellowship. KM acknowledges support from the STFC through an Ernest Rutherford Fellowship. TWC and TK acknowledge the support through the Sofia Kovalevskaja Award to P. Schady from the Alexander von Humboldt Foundation of Germany. The Liverpool Telescope is operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council. The Pan-STARRS1 Surveys (PS1) have been made possible through contributions of the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, the Johns Hopkins Univ
PY - 2017/7
Y1 - 2017/7
N2 - A small group of the newly discovered superluminous supernovae show broad and slowevolving light curves. Here we present extensive observational data for the slow-evolving superluminous supernova LSQ14an, which brings this group of transients to four in total in the low-redshift Universe (z < 0.2; SN 2007bi, PTF12dam, SN 2015bn).We particularly focus on the optical and near-infrared evolution during the period from 50 d up to 400 d from peak, showing that they are all fairly similar in their light curve and spectral evolution. LSQ14an shows broad, blueshifted [O III] λλ4959, 5007 lines, as well as a blueshifted [O II] λλ7320, 7330 and [Ca II] λλ7291, 7323. Furthermore, the sample of these four objects shows common features. Semi-forbidden and forbidden emission lines appear surprisingly early at 50-70 d and remain visible with almost no variation up to 400 d. The spectra remain blue out to 400 d. There are small, but discernible light-curve fluctuations in all of them. The light curve of each shows a faster decline than 56Co after 150 d and it further steepens after 300 d. We also expand our analysis presenting X-ray limits for LSQ14an and SN 2015bn and discuss their diagnostic power. These features are quite distinct from the faster evolving superluminous supernovae and are not easily explained in terms of only a variation in ejecta mass. While a central engine is still the most likely luminosity source, it appears that the ejecta structure is complex, with multiple emitting zones and at least some interaction between the expanding ejecta and surrounding material.
AB - A small group of the newly discovered superluminous supernovae show broad and slowevolving light curves. Here we present extensive observational data for the slow-evolving superluminous supernova LSQ14an, which brings this group of transients to four in total in the low-redshift Universe (z < 0.2; SN 2007bi, PTF12dam, SN 2015bn).We particularly focus on the optical and near-infrared evolution during the period from 50 d up to 400 d from peak, showing that they are all fairly similar in their light curve and spectral evolution. LSQ14an shows broad, blueshifted [O III] λλ4959, 5007 lines, as well as a blueshifted [O II] λλ7320, 7330 and [Ca II] λλ7291, 7323. Furthermore, the sample of these four objects shows common features. Semi-forbidden and forbidden emission lines appear surprisingly early at 50-70 d and remain visible with almost no variation up to 400 d. The spectra remain blue out to 400 d. There are small, but discernible light-curve fluctuations in all of them. The light curve of each shows a faster decline than 56Co after 150 d and it further steepens after 300 d. We also expand our analysis presenting X-ray limits for LSQ14an and SN 2015bn and discuss their diagnostic power. These features are quite distinct from the faster evolving superluminous supernovae and are not easily explained in terms of only a variation in ejecta mass. While a central engine is still the most likely luminosity source, it appears that the ejecta structure is complex, with multiple emitting zones and at least some interaction between the expanding ejecta and surrounding material.
UR - http://www.scopus.com/inward/record.url?scp=85021083704&partnerID=8YFLogxK
U2 - https://doi.org/10.1093/mnras/stx834
DO - https://doi.org/10.1093/mnras/stx834
M3 - مقالة
SN - 0035-8711
VL - 468
SP - 4642
EP - 4662
JO - MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
JF - MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
IS - 4
ER -