Speaker
Prof.
INA SARCEVIC
(UNIVERSITY OF ARIZONA)
Description
The IceCube detection of High Energy Starting Events (HESE) and
the upward muon track events (6 year data) are presently hard to
explain with the single power-law astophysical flux for
energies above 30TeV. We investigate the possibility that a
significant component of the additional neutrino flux originates
due to the decay of a very heavy dark matter particle via several
possible channels into standard model particles. We perform
a full 5 parameter fit to IceCube data in which we vary
astrophysical flux normalization, power-law index, dark matter
mass, dark matter lifetime and dark matter decay mode.
We show that that dark matter with mass in the range 200-400
TeV, lifetime around 10^27s and soft-channel decay mode
(DM --> W^+ W^-, b \bar b, etc) provides much better
fit to IC data than the best-fit astrophysical flux alone.
For hard decay channels such as DM --> nu_e + \bar nu_e,
the best fit is for the dark matter mass of few PeV, thus
contributing only to the highest energy events. We have also
done analysis by using the prior that would fix power-law index
to the best fit value for upward muon track events (gamma \sim 2.13),
and we find that in this case, all decay channels contribute
substaintially, but the fit overall is not as good as
without the prior.
Primary author
Prof.
INA SARCEVIC
(UNIVERSITY OF ARIZONA)
Co-authors
Dr
Arman Esmaili
(INFN, Laboratori Nazionali del Gran Sasso, Assergi (AQ), Italy)
Dr
Atri Bhattacharya
(University of Leige, Belgium)
Dr
Sergio Palomares-Ruiz
(IFIC)