Speaker
Dr
Hao-Ning He
(Purple Mountain Observatory,)
Description
The origins of the reported two PeV neutrinos (by Ice- Cube Collaboration) are highly controversial so far. Ultra-luminous infrared galaxies (ULIRGs) are the most luminous and intense starburst galaxies in the Universe. Both their star-formation rate (SFR) and gas surface mass density are very high, implying a high supernovae rate and an efficient energy conversion of energetic protons. A small fraction of these supernovae is the so-called hypernovae with a typical kinetic energy ~10^52 erg and a shock velocity >=10^9cm s^-1. The strong shocks driven by hypernovae are able to accelerate cosmic ray protons up to 10^17 eV. These energetic protons lose a good fraction of their energy through proton-proton collision when ejected into very dense interstellar medium, and as a result, produce high energy neutrinos (<=5 PeV). Recent deep infrared surveys provide solid constraints on the number density of ULIRGs across a wide redshift range 0
Primary author
Dr
Hao-Ning He
(Purple Mountain Observatory,)
