Constraints on high-energy neutrino emission from SN 2008D

TL;DR

This study searched for high-energy neutrinos from SN 2008D using IceCube data but found no signal, setting upper limits on neutrino flux and constraining models of neutrino emission from supernovae.

Contribution

First search for high-energy neutrinos from SN 2008D with IceCube, providing constraints on neutrino emission models from core collapse supernovae.

Findings

No neutrino events detected in the search windows.

Upper limits set on muon neutrino flux from SN 2008D.

Constraints placed on supernova neutrino emission models.

Abstract

SN 2008D, a core collapse supernova at a distance of 27 Mpc, was serendipitously discovered by the Swift satellite through an associated X-ray flash. Core collapse supernovae have been observed in association with long gamma-ray bursts and X-ray flashes and a physical connection is widely assumed. This connection could imply that some core collapse supernovae possess mildly relativistic jets in which high-energy neutrinos are produced through proton-proton collisions. The predicted neutrino spectra would be detectable by Cherenkov neutrino detectors like IceCube. A search for a neutrino signal in temporal and spatial correlation with the observed X-ray flash of SN 2008D was conducted using data taken in 2007-2008 with 22 strings of the IceCube detector. Events were selected based on a boosted decision tree classifier trained with simulated signal and experimental background data. The classifier was optimized to the position and a "soft jet" neutrino spectrum assumed for SN 2008D. Using three search windows placed around the X-ray peak, emission time scales from 100 - 10000 s were probed. No events passing the cuts were observed in agreement with the signal expectation of 0.13 events. Upper limits on the muon neutrino flux from core collapse supernovae were derived for different emission time scales and the principal model parameters were constrained.