Early hard X-rays from the nearby core-collapse supernova SN2023ixf

Abstract

We present NuSTAR observations of the nearby SN 2023ixf in M101 (d=6.9 Mpc) which provide the earliest hard X-ray detection of a non-relativistic stellar explosion to date at $\delta t\approx$4-d and $\delta t\approx$11-d. The spectra are well described by a hot thermal bremsstrahlung continuum with $T>25\mathrm{keV}$ shining through a thick neutral medium with a neutral hydrogen column that decreases with time (initial $N_{\mathrm{Hint}}=2.6\times 10^{23}\mathrm{c}{\mathrm{m}}^{-2}$). A prominent neutral Fe K$\alpha$ emission line is clearly detected, similar to other strongly interacting SNe such as SN2020jl. The rapidly decreasing intrinsic absorption with time suggests the presence of a dense but confined circumstellar medium (CSM). The absorbed broadband X-ray luminosity (0.3--79 keV) is $L_X\approx 2.5\times 10^{40}$ erg s${}^{-1}$ during both epochs, with the increase in overall X-ray flux related to the decrease in the absorbing column. Interpreting these observations in the context of thermal bremsstrahlung radiation originating from the interaction of the SN shock with a dense medium we infer large particle densities in excess of $n_{\mathrm{CSM}}\approx 4\times 10^8\mathrm{c}{\mathrm{m}}^{-3}$ at $r<10^{15}\mathrm{cm}$, corresponding to an enhanced progenitor mass-loss rate of $\dot{M}\approx 3\times 10^{-4}$ M${}_{\odot }$ yr${}^{-1}$ for an assumed wind velocity of $v_w=50$ km s${}^{-1}$.

8 pages, 2 figures. Submitted

References in corpus (18)

• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• A Comprehensive Measurement of the Local Value of the Hubble Constant with 1 km/s/Mpc Uncertainty from the Hubble Space Telescope and the SH0ES Team
• An online repository of Swift/XRT light curves of GRBs
• A giant outburst two years before the core-collapse of a massive star
• Confined Dense Circumstellar Material Surrounding a Regular Type II Supernova: The Unique Flash-Spectroscopy Event of SN 2013fs
• A Wolf-Rayet-like progenitor of supernova SN 2013cu from spectral observations of a wind
• Circumstellar Emission from Type Ib and Ic Supernovae
• Massive stars exploding in a He-rich circumstellar medium. I. Type Ibn (SN 2006jc-like) events
• A new mass-loss rate prescription for red supergiants
• Final Moments I: Precursor Emission, Envelope Inflation, and Enhanced Mass loss Preceding the Luminous Type II Supernova 2020tlf
• Bright, months-long stellar outbursts announce the explosion of interaction-powered supernovae
• The Type Icn SN 2021csp: Implications for the Origins of the Fastest Supernovae and the Fates of Wolf-Rayet Stars
• Supernovae 2016bdu and 2005gl, and their link with SN 2009ip-like transients: another piece of the puzzle
• Modeling the signatures of interaction in Type II supernovae: UV emission, high-velocity features, broad-boxy profiles
• The Early Phases of Supernova 2020pni: Shock-Ionization of the Nitrogen-Enriched Circumstellar Material
• Luminous Late-time Radio Emission from Supernovae Detected by the Karl G. Jansky Very Large Array Sky Survey (VLASS)
• The Time-Averaged Mass-Loss Rates of Red Supergiants As Revealed by their Luminosity Functions in M31 and M33
• Seven Years of SN 2014C: a Multi-Wavelength Synthesis of an Extraordinary Supernova

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