RINGO3 polarimetry of very young ZTF supernovae

Creators: Maund, J. R.; Yang, Y.; Steele, I. A.; Baade, D.; Jermak, H.; Schulze, S.; Bruch, R.; Gal-Yam, A.; Höflich, P. A.; Ofek, E.; Wang, X.; Amenouche, M.; Dekany, R.; Masci, F. J.; Riddle, R.; Soumagnac, M. T.

Abstract

The early phases of the observed evolution of the supernovae (SNe) are expected to be dominated by the shock breakout and 'flash' ionization of the surrounding circumstellar medium. This material arises from the last stages of the evolution of the progenitor, such that photometry and spectroscopy of SNe at early times can place vital constraints on the latest and fastest evolutionary phases leading up to stellar death. These signatures are erased by the expansion of the ejecta within ∼5 d after explosion. Here we present the earliest constraints, to date, on the polarization of 10 transients discovered by the Zwicky Transient Facility (ZTF), between 2018 June and 2019 August. Rapid polarimetric follow-up was conducted using the Liverpool Telescope RINGO3 instrument, including three SNe observed within <1 d of detection by the ZTF. The limits on the polarization within the first 5 d of explosion, for all SN types, is generally <2per cent⁠, implying early asymmetries are limited to axial ratios >0.65 (assuming an oblate spheroidal configuration). We also present polarimetric observations of the Type I Superluminous SN 2018bsz and Type II SN 2018hna, observed around and after maximum light.

Additional Information

© 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). Accepted 2021 February 3. Received 2021 February 1; in original form 2020 October 21. Published: 13 February 2021. The Liverpool Telescope is operated on the island of La Palma by Liverpool John Moores University at the Spanish Obervatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, with financial support from the UK Science and Technologies Facilities Council (STFC). Financial support for the development RINGO3 was also provided by the STFC Project Research and Development (PRD) scheme. 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. The research of JRM was supported through a Royal Society Research Fellowship. The research of YY is supported through a Benoziyo Prize Postdoctoral Fellowship. The research of AGY 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. The work of XW is supported by National Natural Science Foundation of China (NSFC grants 11325313, 11633002, and 11761141001), and the National Program on Key Research and Development Project (grant no. 2016YFA0400803). The authors thank S. Van Dyk for useful comments on the manuscript. Data Availability: The observational data presented here is available in the public archive of the Liverpool Telescope (https://telescope.livjm.ac.uk/cgi-bin/lt_search)

Attached Files

Published - stab391.pdf

Files

stab391.pdf

Files (3.2 MB)

Name	Size	Download all
stab391.pdf md5:2d48ae94fcb6b86c6390fce484bebcea	3.2 MB	Preview Download

Additional details

	All versions	This version
Views	0	0
Downloads	0	0
Data volume	0 Bytes	0 Bytes