Speaker
Andrey Elagin
(University of Chicago)
Description
We present initial studies of a technique for separating scintillation and
Cherenkov light in a large liquid scintillator detector in order to
reconstruct directionality for electrons with energies typical of
neutrino-electron scattering (5 MeV) and double-beta decay (2.1 MeV
and 1.4 MeV).
On average scintillation light is delayed with respect to the direct
Cherenkov light due to chromatic dispersion and the finite time of
the scintillation processes; early light thus contains directional
information. Using a GEANT4 simulation of a 6.5m-radius
spherical detector with 100% coverage of photodetectors having
transit-time-spread (TTS) of 100 ps, we have shown that a time cut
on the early light is effective at isolating the directional light,
improving the ratio of Cherenkov to scintillation light from
$R_{c/s}$=0.02 to $R_{c/s}$=0.63 for 5 MeV electrons originating at
the detector center. This ratio is degraded by a factor of 2.5 if
typical photomultipliers with TTS=1.28 ns are used. The ratio for TTS=100 ps
can be further improved by a factor of 1.6 by using red-enhanced
photocathodes, or by 1.4 by using narrow-emission scintillators.
We discuss a technique for extracting particle direction, and evaluate
several detector developments in timing, photodetector spectral response,
and scintillator emission spectra that could be used to realize direction
reconstruction in a kiloton-scale detector.
Summary
See http://arxiv.org/abs/1307.5813
Primary authors
Andrey Elagin
(University of Chicago)
Christoph Aberle
(University of California, Los Angeles)
Henry Frisch
(University of Chicago)
Lindley Winslow
(University of California, Los Angeles)
Matthew Wetstein
(University of Chicago)
