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A non-equipartition shockwave traveling in a dense circumstellar environment around SN2020oi

Horesh, Assaf and Sfaradi, Itai and Ergon, Mattias and Barbarino, Cristina and Sollerman, Jesper and Moldon, Javier and Dobie, Dougal and Schulze, Steve and Pérez-Torres, Miguel and Williams, David R. A. and Fremling, Christoffer and Gal-Yam, Avishay and Kulkarni, Shrinivas R. and O'Brien, Andrew and Lundqvist, Peter and Murphy, Tara and Fender, Rob and Belicki, Justin and Bellm, Eric C. and Coughlin, Michael W. and Ofek, Eran O. and Golkhou, V. Zach and Graham, Matthew J. and Green, Dave A. and Kupfer, Thomas and Laher, Russ R. and Masci, Frank J. and Miller, Adam A. and Neill, James D. and Perrott, Yvette and Porter, Michael and Reiley, Daniel J. and Rigault, Mickael and Rodriguez, Hector and Rusholme, Ben and Shupe, David L. and Titterington, David (2020) A non-equipartition shockwave traveling in a dense circumstellar environment around SN2020oi. . (Unpublished)

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We report the discovery and panchromatic followup observations of the young Type Ic supernova, SN2020oi, in M100, a grand design spiral galaxy at a mere distance of 14 Mpc. We followed up with observations at radio, X-ray and optical wavelengths from only a few days to several months after explosion. The optical behaviour of the supernova is similar to those of other normal Type Ic supernovae. The event was not detected in the X-ray band but our radio observation revealed a bright mJy source (L_ν ≈ 1.2 × 10²⁷ ergs⁻¹ Hz⁻¹). Given, the relatively small number of stripped envelope SNe for which radio emission is detectable, we used this opportunity to perform a detailed analysis of the comprehensive radio dataset we obtained. The radio emitting electrons initially experience a phase of inverse Compton cooling which leads to steepening of the spectral index of the radio emission. Our analysis of the cooling frequency points to a large deviation from equipartition at the level of ϵ_e/ϵ_B ≳ 200, similar to a few other cases of stripped envelope SNe. Our modeling of the radio data suggests that the shockwave driven by the SN ejecta into the circumstellar matter (CSM) is moving at ∼3 × 10⁴ km s⁻¹. Assuming a constant mass-loss from the stellar progenitor, we find that the mass-loss rate is Ṁ ≈ 1.4 × 10⁻⁴ M_⊙ yr⁻¹, for an assumed wind velocity of 1000 km s⁻¹. The temporal evolution of the radio emission suggests a radial CSM density structure steeper than the standard r⁻².

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
Horesh, Assaf0000-0002-5936-1156
Barbarino, Cristina0000-0002-3821-6144
Sollerman, Jesper0000-0003-1546-6615
Dobie, Dougal0000-0003-0699-7019
Schulze, Steve0000-0001-6797-1889
Williams, David R. A.0000-0001-7361-0246
Fremling, Christoffer0000-0002-4223-103X
Gal-Yam, Avishay0000-0002-3653-5598
Kulkarni, Shrinivas R.0000-0001-5390-8563
Lundqvist, Peter0000-0002-3664-8082
Murphy, Tara0000-0002-2686-438X
Bellm, Eric C.0000-0001-8018-5348
Coughlin, Michael W.0000-0002-8262-2924
Ofek, Eran O.0000-0002-6786-8774
Golkhou, V. Zach0000-0001-8205-2506
Graham, Matthew J.0000-0002-3168-0139
Kupfer, Thomas0000-0002-6540-1484
Laher, Russ R.0000-0003-2451-5482
Masci, Frank J.0000-0002-8532-9395
Miller, Adam A.0000-0001-9515-478X
Neill, James D.0000-0002-0466-1119
Perrott, Yvette0000-0002-6255-8240
Porter, Michael0000-0003-3168-5586
Rigault, Mickael0000-0002-8121-2560
Rusholme, Ben0000-0001-7648-4142
Shupe, David L.0000-0003-4401-0430
Additional Information:A.H. is grateful for the support by grants from the Israel Science Foundation, the US-Israel Binational Science Foundation (BSF), and the I-CORE Program of the Planning and Budgeting Committee and the Israel Science Foundation. T.M. acknowledges the support of the Australian Research Council through grant FT150100099. D.D. is supported by an Australian Government Research Training Program Scholarship. D.R.A.W was supported by the Oxford Centre for Astrophysical Surveys, which is funded through generous support from the Hintze Family Charitable Foundation. A. A. Miller is funded by the Large Synoptic Survey Telescope Corporation, the Brinson Foundation, and the Moore Foundation in support of the LSSTC Data Science Fellowship Program; he also receives support as a CIERA Fellow by the CIERA Postdoctoral Fellowship Program (Center for Interdisciplinary Exploration and Research in Astrophysics, Northwestern University). M.P.T acknowledges financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofsica de Andaluca (SEV-2017-0709) and through grant PGC2018-098915-B-C21 (MCI/AEI/FEDER, UE). J.M. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa" award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709) and from the grant RTI2018-096228-B-C31 (MICIU/FEDER, EU). A.G.Ys research is supported by the EU via ERC grant No. 725161, the ISF GW excellence center, an IMOS space infrastructure grant and BSF/Transformative and GIF grants, as well as The Benoziyo Endowment Fund for the Advancement of Science, the Deloro Institute for Advanced Research in Space and Optics, The Veronika A. Rabl Physics Discretionary Fund, Paul and Tina Gardner, Yeda-Sela and the WIS-CIT joint research grant; AGY is the recipient of the Helen and Martin Kimmel Award for Innovative Investigation. M.R. has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement n759194 - USNAC). M. W. Coughlin acknowledges support from the National Science Foundation with grant number PHY-2010970. C.F. gratefully acknowledges support of his research by the Heising-Simons Foundation (#2018-0907). Based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-1440341 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, the University of Washington, Deutsches Elektronen- Synchrotron and Humboldt University, Los Alamos National Laboratories, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, and Lawrence Berkeley National Laboratories. Operations are conducted by COO, IPAC, and UW. Partly based on observations made with the Nordic Optical Telescope. SED Machine is based upon work supported by the National Science Foundation under Grant No. 1106171. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under co-operative agreement by Associated Universities, Inc. The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Gomeroi people as the traditional owners of the Observatory site. e-MERLIN is a National Facility operated by the University of Manchester at Jodrell Bank Observatory on behalf of STFC. We thank the staff of the Mullard Radio Astronomy Observatory for their assistance in the commissioning, maintenance and operation of AMI, which is supported by the Universities of Cambridge and Oxford. We also acknowledge support from the European Research Council under grant ERC-2012-StG-307215 LODESTONE.
Group:Astronomy Department, Infrared Processing and Analysis Center (IPAC), Zwicky Transient Facility
Funding AgencyGrant Number
Israel Science FoundationUNSPECIFIED
Binational Science Foundation (USA-Israel)UNSPECIFIED
I-CORE Program of the Planning and Budgeting CommitteeUNSPECIFIED
Australian Research CouncilFT150100099
Australian Government Research Training ProgramUNSPECIFIED
Hintze Family Charitable FoundationUNSPECIFIED
LSSTC Institutional MembersUNSPECIFIED
Brinson FoundationUNSPECIFIED
Gordon and Betty Moore FoundationUNSPECIFIED
Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)UNSPECIFIED
Ministerio de Ciencia, Innovación y Universidades (MCIU)UNSPECIFIED
Severo OchoaSEV-2017-0709
Severo OchoaPGC2018-098915-B-C21
Ministerio de Ciencia, Innovación y Universidades (MCIU)RTI2018-096228-B-C31
Fondo Europeo de Desarrollo Regional (FEDER)UNSPECIFIED
European Research Council (ERC)725161
Ministry of Science (Israel)UNSPECIFIED
German-Israeli Foundation for Research and DevelopmentUNSPECIFIED
Benoziyo Endowment Fund for the Advancement of ScienceUNSPECIFIED
Deloro Institute for Advanced Research in Space and OpticsUNSPECIFIED
Veronika A. Rabl Physics Discretionary FundUNSPECIFIED
Paul and Tina GardnerUNSPECIFIED
Weizmann Institute of ScienceUNSPECIFIED
Helen and Martin Kimmel AwardUNSPECIFIED
European Research Council (ERC)759194
Heising-Simons Foundation2018-0907
ZTF partner institutionsUNSPECIFIED
Science and Technology Facilities Council (STFC)UNSPECIFIED
University of CambridgeUNSPECIFIED
University of OxfordUNSPECIFIED
European Research Council (ERC)307215
Record Number:CaltechAUTHORS:20200916-112923664
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:105421
Deposited By: George Porter
Deposited On:17 Sep 2020 20:53
Last Modified:17 Sep 2020 20:53

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