Gamma-rays and neutrinos from very young supernova remnants

Abstract

We consider the result of acceleration of heavy ions in the slot gap potential of a very young pulsar with a hot polar cap. Photodisintegration of the heavy ions in the radiation field of the polar cap and pulsar surface gives rise to a flux of energetic neutrons. Some fraction of these neutrons interact with target nuclei in the supernova shell to produce neutrino and gamma-ray signals which should be observable from very young supernova remnants in our galaxy for a range of pulsar parameters.

Galactic discrete sources of high energy neutrinos

“…A more specific model for γ-ray and neutrino production in the Crab Nebula has been proposed a few years ago by Bednarek and Protheroe (1997). The general scenario is similar to the one previously discussed for the very young supernova remnants (Protheroe et al 1998): iron nuclei from the Crab pulsar are accelerated in the outer gap (Cheng et al 1986) and photodisintegrate in collisions with the non-thermal radiation field filling the outer gap, thus producing energetic neutrons which are injected into the nebula. Neutrons can decay either inside or outside the Crab nebula.…”

“…Gaisser et al (1989). In this review, we consider more recent models, starting from the one developed by Protheroe et al (1998). In this model the authors suppose that a pulsar with sufficiently short rotational period and high magnetic field has been formed just after the supernova explosion.…”

“…56 F e nuclei, extracted from the star surface by thermoionic emission, are gradually accelerated in the slot gap and suffer photodisintegrations in collisions with the thermal photons coming from the neutron star surface. To check if photodisintegration of 56 F e nuclei is important, Protheroe et al (1998) compute the average number of neutrons extracted from 56 F e nuclei as a function of their Lorentz factor, assuming that in each photodisintegration only one neutron is extracted. It is found that this process occurs efficiently only if the surface temperature is quite high, above ≈ 10 7 K, i.e.…”

Neutrinos from Relativistic Outflows of Fast Spinning Magnetars

“…As neutrons have a relatively long decay time, ∼ 10 3 γ p s in the observer's frame, they may decay outside the remnant (Protheroe, Bednarek, & Luo 1998). The charged pion decay produces neutrinos, π + → µ + + ν µ → e + + ν e + ν µ + ν µ .…”

Contribution of nuclei accelerated by gamma-ray pulsars to cosmic rays in the Galaxy

“…In our previous work [17,18], we considered acceleration of iron nuclei in the magnetospheres of very young pulsars, and Crab-type pulsars, in the context of γ-ray and neutrino emission by supernova remnants. We found that, although the photo-disintegration process of iron nuclei during their acceleration and propagation through the neutron star magnetosphere is important, heavy nuclei would be injected into the medium of expanding supernova remnant.…”