TeV Neutrinos and Gamma rays from Pulsars/Magnetars. Arunava Bhadra High Energy & Cosmic Ray Research Ctr. North Bengal University. Introduction. The energy spectrum of cosmic rays extends to extremely high energies, values exceeding 10 20 eV .
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TeV Neutrinos and Gamma rays from Pulsars/Magnetars
High Energy & Cosmic Ray Research Ctr.
North Bengal University
electron may be accelerated
or may lead acceleration of positive ions
BS is the strength of magnetic field at neutron star surface
RS is the radius of the neutron star
is the angular velocity
~ 7 1018 B12Pms-2
BS=B12 1012 G, Pms is the pulsar period in millisecond.
μ · Ω < 0
(such a condition is expected to hold for half of the total pulsars).
p(1-cosp) 0.3 GeV2
p Proton energy, photon energy
p angle between proton and photon in the Lab frame.
2.8 kTS (1+zg)
TS is the surface temperature of Neutron star
B12 Pms-2T0.1keV 3 10-4
T0.1keV (kTS/0.1 keV),
typical surface temperature of neutron star is 0.1 keV
q = eZnGJ
where nGJ BsR3/(4Zecr3) is the Goldreich–Julian density at distance r
gap = fd(1-fd)nGJ
is the ratio of the polar cap area to the neutron star surface area.
n(RS) = (/2.8k)[(1+zg)TS]3
being the Stefan–Boltzmann constant.
n(r) = n(RS) (RS/r)2
PC =1 -rRSP(r)dr
dP/P =- n(r)Pdr
L/PC = 2cgapAPCPC
= 4/3 for photon
= 2/3 for mu-neutrino
fb is the duty cycle of the gamma-ray/neutrino beam (typically fb ∼ 0.1– 0.3)
(the decays of pions and their muon daughters result in initial ﬂavour ratios φνe : φνμ : φντ of nearly 1:2:0 but at large distance from the source the ﬂavour ratio is expected to become 1:1:1 due to maximal mixing of νμ and ντ .).
P ~ 1.3 10-6 (/1 TeV)
β represents the fraction of pulsar-accelerated protons trapped in the nebula and t is the age of the pulsar.
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