Speaker
ryoichi katsuya
Description
Cosmic ray nuclear composition has a very important role to reveal the origin of cosmic rays.
Especially, composition with energy around knee region must be related to the mechanisms of particle accelerations.
In the BASJE (Borivian Air Shower Joint Experiment) group,
we constructed new large air shower array at Mount Chacaltaya (5,200m above sea level)
to observe air showers with energies above $10^{15}$ eV,
and has operated since 2010.
In addition,
We installed 7 Cherenkov light detectors radially from the center of the air shower array with 50m intervals,
and started to measure air shower development by
the Cherenkov light emitted from air shower particles.
It is known that the longitudinal development
of air shower strongly
depends on the type of the primary nucleus, and
the Cherenkov light emitted from air shower electrons is
closely correlated to the air shower longitudinal development.
Actually, we performed a Monte-Carlo simulation of Cherenkov light emissions from air showers
and found that primary cosmic ray nuclei types can be distinguished
by measuring lateral distributions and arrival timings (waveforms) of Cherenkov lights
associated with air showers.
Since 2012, we have started operation
of the Cherenkov detectors along with the air shower array.
In this paper, we present the characteristics of the new detectors
and preliminary results from the first observation.
| Registration number following "ICRC2015-I/" | 1008 |
|---|---|
| Collaboration | -- not specified -- |
Author
Co-authors
Fumio Kakimoto
(Tokyo Institute of Technology)
Hisao Tokuno
(UTokyo)
Nakayama Kesuke
(Tokyo Institute of Technology)
Norio Tajima
(Institute of Physical and Chemical Research (RIKEN))
Shoichi Ogio
(Osaka City University)
Yoshiki Tsunesada
(Tokyo Institute of Technology)
Yutaka Matsubara
(Solar-Terrestrial Environment Laboratory, Nagoya University)
