Simultaneous measurement of ionization and scintillation from nuclear recoils in liquid xenon for a dark matter experiment.
We report the first measurements of the absolute ionization yield of nuclear recoils in liquid xenon, as a function of energy and electric field. Independent experiments were carried out with two dual-phase time-projection chamber prototypes, developed for the XENON dark matter project. We find that the charge yield increases with decreasing recoil energy, and exhibits only a weak field dependence. These results are the first unambiguous demonstration of the capability of dual-phase xenon detectors to discriminate between electron and nuclear recoils down to 20 keV, a key requirement for a sensitive dark matter search.
Aprile
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Physics Department and Columbia Astrophysics Laboratory, Columbia University, New York, New York 10027, USA. age@astro.columbia.edu
Dahl
C E
CE
de Viveiros
L
L
Gaitskell
R J
RJ
Giboni
K L
KL
Kwong
J
J
Majewski
P
P
Ni
K
K
Shutt
T
T
Yamashita
M
M