In which shell-type SNRs should we look for gamma-rays and neutrinos from p-p collisions?

Details In which shell-type SNRs should we look for gamma-rays and neutrinos from p-p collisions? In which shell-type SNRs should we look for gamma-rays and neutrinos from p-p collisions?

2007-06-24

arxiv.org/abs/0706.3485v3

JCAP0801:018,2008

Astronomy and Astrophysics

Astrophysics

13 pages, 1 figure, accepted for publication in JCAP, minor revisions

Scientific paper

10.1088/1475-7516/2008/01/018

We present a simple analytic model for the various contributions to the non-thermal emission from shell type SNRs, and show that this model's results reproduce well the results of previous detailed calculations. We show that the \geq 1 TeV gamma ray emission from the shell type SNRs RX J1713.7-3946 and RX J0852.0-4622 is dominated by inverse-Compton scattering of CMB photons (and possibly infra-red ambient photons) by accelerated electrons. Pion decay (due to proton-proton collisions) is shown to account for only a small fraction, \lesssim10^-2, of the observed flux, as assuming a larger fractional contribution would imply nonthermal radio and X-ray synchrotron emission and thermal X-ray Bremsstrahlung emission that far exceed the observed radio and X-ray fluxes. Models where pion decay dominates the \geq 1 TeV flux avoid the implied excessive synchrotron emission (but not the implied excessive thermal X-ray Bremsstrahlung emission) by assuming an extremely low efficiency of electron acceleration, K_ep \lesssim 10^-4 (K_ep is the ratio of the number of accelerated electrons and the number of accelerated protons at a given energy). We argue that observations of SNRs in nearby galaxies imply a lower limit of K_ep \gtrsim 10^-3, and thus rule out K_ep values \lesssim 10^-4 (assuming that SNRs share a common typical value of K_ep). It is suggested that SNRs with strong thermal X-ray emission, rather than strong non-thermal X-ray emission, are more suitable candidates for searches of gamma rays and neutrinos resulting from proton-proton collisions. In particular, it is shown that the neutrino flux from the SNRs above is probably too low to be detected by current and planned neutrino observatories (Abridged).

Affiliated with

Also associated with

No associations

Rating

In which shell-type SNRs should we look for gamma-rays and neutrinos from p-p collisions? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with In which shell-type SNRs should we look for gamma-rays and neutrinos from p-p collisions?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and In which shell-type SNRs should we look for gamma-rays and neutrinos from p-p collisions? will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-703979