Luminous Radio Emission from the Superluminous Supernova 2017ens at 3.3 years after explosion. (arXiv:2306.13730v1 [astro-ph.HE])

Luminous Radio Emission from the Superluminous Supernova 2017ens at 3.3 years after explosion. (arXiv:2306.13730v1 [astro-ph.HE])
<a href="http://arxiv.org/find/astro-ph/1/au:+Margutti_R/0/1/0/all/0/1">Raffaella Margutti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bright_J/0/1/0/all/0/1">J. S. Bright</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Matthews_D/0/1/0/all/0/1">D. J. Matthews</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Coppejans_D/0/1/0/all/0/1">D. L. Coppejans</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Alexander_K/0/1/0/all/0/1">K. D. Alexander</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Berger_E/0/1/0/all/0/1">E. Berger</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bietenholz_M/0/1/0/all/0/1">M. Bietenholz</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chornock_R/0/1/0/all/0/1">R. Chornock</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+DeMarchi_L/0/1/0/all/0/1">L. DeMarchi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Drout_M/0/1/0/all/0/1">M. R. Drout</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Eftekhari_T/0/1/0/all/0/1">T. Eftekhari</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jacobson_Galan_W/0/1/0/all/0/1">W. V. Jacobson-Galan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Laskar_T/0/1/0/all/0/1">T. Laskar</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Milisavljevic_D/0/1/0/all/0/1">D. Milisavljevic</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Murase_K/0/1/0/all/0/1">K. Murase</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nicholl_M/0/1/0/all/0/1">M. Nicholl</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Omand_C/0/1/0/all/0/1">C. M. B. Omand</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Stroh_M/0/1/0/all/0/1">M. Stroh</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Terreran_G/0/1/0/all/0/1">G. Terreran</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+VanderLey_A/0/1/0/all/0/1">A. Z. VanderLey</a>

We present the results from a multi-year radio campaign of the superluminous
supernova (SLSN) 2017ens, which yielded the earliest radio detection of a SLSN
to date at the age of $sim$3.3 years after explosion. SN2017ens was not
detected at radio frequencies in the first $sim$300,d of evolution but
reached $L_{nu}approx 10^{28},rm{erg,s^{-1},cm^{-2}}$ at $nusim 6$ GHz,
$sim1250$ days post-explosion. Interpreting the radio observations in the
context of synchrotron radiation from the supernova shock interaction with the
circumstellar medium (CSM), we infer an effective mass-loss rate of $approx
10^{-4},rm{M_{odot}yr^{-1}}$ at $rsim 10^{17}$ cm from the explosion’s
site, for a wind speed of $v_w=50-60,rm{km,s^{-1}}$ measured from optical
spectra. These findings are consistent with the spectroscopic metamorphosis of
SN2017ens from hydrogen-poor to hydrogen-rich $sim190$ d after explosion
reported by Chen et al., 2018. SN2017ens is thus an addition to the sample of
hydrogen-poor massive progenitors that explode shortly after having lost their
hydrogen envelope. The inferred circumstellar densities, implying a CSM mass up
to $sim0.5,rm{M_{odot}}$, and low velocity of the ejection point at binary
interactions (in the form of common envelope evolution and subsequent envelope
ejection) playing a role in shaping the evolution of the stellar progenitors of
SLSNe in the $lesssim 500$ yr preceding core collapse.

http://arxiv.org/icons/sfx.gif