Particles are detected by electric
pulses coming from 2000 photomultiplier tubes (pmts) in KamLAND.
A team of Berkeley engineers and physicists designed and built electronics
optimized to get the most information possible from the pmts.
In order to correctly interpret
the data, well characterized sources of events are deployed into the detector.
A safe and accurate system to deploy sources was designed in part by a team
Even though neutrino
are few and far inbetween, KamLAND records ~30 events a second which
into more than 200GB of data a day. This data needs to be stored,
analyzed and processed into physical quantities such as, time and
charge, vertexes and finally neutrino candidate events.
Collaborators at Berkeley have worked with NERSC to utilize the HPSS
storage system and PDSF processing facilities.
As the raw data is processed
into higher levels of information, it takes time to put together the data, the
physics, and the knowledge of the detector's response to produce an answer.
Berkeley physicists have been heavily involved with their collaborators in
all levels of the analysis.
Cosmic ray muons incident on the KamLAND detector are presently identified by the high levels of charge deposited in the inner and outer PMT arrays. Muon trajectories are inferred from the charge arrival time distributions, and this data will be used to calibrate the muon reconstruction algorithm used for the main detector, and to measure the efficiency of the muon tagging procedure.