We have studied the feasibility of a silicon photomultiplier (SiPM) to detect liquid xenon (LXe) scintillation light. The SiPM was operated inside a small volume of pure liquid xenon (LXe), at
-
95
∘
...C
, irradiated with an internal
241Am
α
source. The gain of the SiPM at this temperature was estimated to be
1.8
×
10
6
at a 52
V bias voltage. Based on the geometry of the setup, the quantum efficiency of the SiPM was estimated to be 22% (5.5% is the photon detection efficiency) at the Xe wavelength of 178
nm. The low excess noise factor (about 1.05), high single photoelectron detection efficiency, and low bias voltage of SiPMs make them attractive alternative UV photon detection devices to photomultiplier tubes (PMTs) for liquid xenon detectors, especially for experiments requiring a very low energy detection threshold, such as neutralino dark matter searches.
XENON10 is an experiment designed to directly detect particle dark matter. It is a dual phase (liquid/gas) xenon time-projection chamber with 3D position imaging. Particle interactions generate a ...primary scintillation signal (
S
1
) and ionization signal (
S
2
), which are both functions of the deposited recoil energy and the incident particle type. We present a new precision measurement of the relative scintillation yield
L
eff
and the absolute ionization yield
Q
y
, for nuclear recoils in xenon. A dark matter particle is expected to deposit energy by scattering from a xenon nucleus. Knowledge of
L
eff
is therefore crucial for establishing the energy threshold of the experiment; this in turn determines the sensitivity to particle dark matter. Our
L
eff
measurement is in agreement with recent theoretical predictions above 15
keV nuclear recoil energy, and the energy threshold of the measurement is
∼
4
keV
. A knowledge of the ionization yield
Q
y
is necessary to establish the trigger threshold of the experiment. The ionization yield
Q
y
is measured in two ways, both in agreement with previous measurements and with a factor of 10 lower energy threshold.
Observations on all fronts strongly support the view of a universe composed of >96% invisible matter and energy. The invisible matter is non-baryonic, cold and likely in the form of new particles ...generically referred to as Weakly Interacting Massive Particles (WIMPs), relics from the early universe. One way to detect WIMPs is to measure the nuclear recoils produced in their rare elastic collisions with ordinary matter. The predicted interaction rate ranges from the best sensitivity of existing experiments of ~1 evts/kg/yr to ~1 evts/1000 kg/yr. Efforts are underway worldwide to realize sensitive direct detection experiments, with large target mass and improved background rejection capabilities. In this talk I will review experiments headed in this direction with the use of cryogenic noble liquids, focusing on those experiments which use the common technique of a dual-phase (liquid/gas) time projection chamber to measure simultaneously the ionization and the scintillation signals produced by radiation in a large volume of liquid xenon or liquid argon. These include experiments such as XENON, ZEPLIN, WARP and ArDM.
Liquid xenon detectors for particle physics and astrophysics Aprile, E.; Doke, T.; Advanced Research Institute for Science and Engineering, Waseda University, Tokyo 169-8555
Reviews of modern physics,
07/2010, Volume:
82, Issue:
3
Journal Article
Peer reviewed
Open access
This article reviews the progress made over the last 20 years in the development and applications of liquid xenon detectors in particle physics, astrophysics, and medical imaging experiments. A ...summary of the fundamental properties of liquid xenon as radiation detection medium, in light of the most current theoretical and experimental information is first provided. After an introduction of the different type of liquid xenon detectors, a review of past, current, and future experiments using liquid xenon to search for rare processes and to image radiation in space and in medicine is given. Each application is introduced with a survey of the underlying scientific motivation and experimental requirements before reviewing the basic characteristics and expected performance of each experiment. Within this decade it appears likely that large volume liquid xenon detectors operated in different modes will contribute to answering some of the most fundamental questions in particle physics, astrophysics, and cosmology, fulfilling the most demanding detection challenges. From detectors based solely on liquid xenon (LXe) scintillation, such as in the MEG experiment for the search of the rare ''{mu}{yields}e{gamma}'' decay, currently the largest liquid xenon detector in operation, and in the XMASS experiment for dark matter detection, to the class of time projection chambers which exploit both scintillation and ionization of LXe, such as in the XENON dark matter search experiment and in the Enriched Xenon Observatory for neutrinoless double beta decay, unrivaled performance and important contributions to physics in the next few years are anticipated.
We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in ...Italy and the first ton-scale detector of this kind. The blinded search used 34.2 live days of data acquired between November 2016 and January 2017. Inside the (1042±12)-kg fiducial mass and in the 5,40 keV_{nr} energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (1.93±0.25)×10^{-4} events/(kg×day×keV_{ee}), the lowest ever achieved in such a dark matter detector. A profile likelihood analysis shows that the data are consistent with the background-only hypothesis. We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10 GeV/c^{2}, with a minimum of 7.7×10^{-47} cm^{2} for 35-GeV/c^{2} WIMPs at 90% C.L.
Direct dark matter detection experiments based on a liquid xenon target are leading the search for dark matter particles with masses above ∼5 GeV/c^{2}, but have limited sensitivity to lighter ...masses because of the small momentum transfer in dark matter-nucleus elastic scattering. However, there is an irreducible contribution from inelastic processes accompanying the elastic scattering, which leads to the excitation and ionization of the recoiling atom (the Migdal effect) or the emission of a bremsstrahlung photon. In this Letter, we report on a probe of low-mass dark matter with masses down to about 85 MeV/c^{2} by looking for electronic recoils induced by the Migdal effect and bremsstrahlung using data from the XENON1T experiment. Besides the approach of detecting both scintillation and ionization signals, we exploit an approach that uses ionization signals only, which allows for a lower detection threshold. This analysis significantly enhances the sensitivity of XENON1T to light dark matter previously beyond its reach.
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