The First results of the Tokyo dark matter search programme using a 21-g lithium fluoride bolometer are presented. The background spectrum was measured in the surface laboratory. We derive an exclusion plot for the spin-dependently coupled Weakly Interacting Massive Particles (WIMPs) cross section.
Tokyo group has performed first underground dark matter search experiment in 2001 through 2002 at Kamioka Observatory(2700m.w.e). The detector is eight LiF bolometers with total mass 168g aiming for the direct detection of WIMPs via spin-dependent interaction. With a total exposure of 4.1 kg days, we derived the limits in the a_p-a_n (WIMP-nucleon couplings) plane and excluded a large part of the parameter space allowed by the UKDMC experiment.
This paper describes the operation of the Coherent CAPTAIN-Mills (CCM) detector located in the Lujan Neutron Science Center at Los Alamos National Laboratory. CCM is a 10-ton liquid argon (LAr) detector located 20 meters from a high flux neutron/neutrino source and is designed to search for sterile neutrinos and light dark matter. An engineering run was performed in Fall 2019 to study the characteristics of the CCM120 detector by searching for signals consistent with sterile neutrinos and light dark matter resulting from $pi^+$ and $pi^0$ decays in the tungsten target. New parameter space in a leptophobic dark matter model was excluded for dark matter masses between $sim2.5$ and 60 MeV. The lessons learned from this run have guided the development and construction of the new CCM200 detector that will begin operations in 2021 and significantly improve on these searches.
We report on the first dark-matter (DM) search results from PandaX-I, a low threshold dual-phase xenon experiment operating at the China Jinping Underground Laboratory. In the 37-kg liquid xenon target with 17.4 live-days of exposure, no DM particle candidate event was found. This result sets a stringent limit for low-mass DM particles and disfavors the interpretation of previously-reported positive experimental results. The minimum upper limit, $3.7times10^{-44}$,cm$^2$, for the spin-independent isoscalar DM-particle-nucleon scattering cross section is obtained at a DM-particle mass of 49,GeV/c$^2$ at 90% confidence level.
We report an improved SIMPLE experiment comprising four superheated droplet detectors with a total exposure of 0.42 kgd. The result yields ~ factor 10 improvement in the previously-reported results, and -- despite the low exposure -- is seen to provide restrictions on the allowed phase space of spin-dependent coupling strengths almost equivalent to those from the significantly larger exposure NAIADCDMS/ZEPLIN searches.
Sensitive n-type and p-type germanium thermistors were fabricated by the melt doping technique and by the neutron transmutation doping (NTD) technique, respectively, aiming at a use for the cryogenic thermal detector, or bolometer of Tokyo dark matter search programme. We report on the measurements of the sensitivities of these thermistors. In particular, the p-type thermistors are sensitive enough to scale up our existing prototype LiF bolometer and realize a multiple array of the bolometers with the total absorber mass of about 1,kg.
Wataru Ootani
,Makoto Minowa
,Takayuki Watanabe
.
(1997)
.
"First Results of Tokyo Dark Matter Search with a Lithium Fluoride Bolometer"
.
Wataru Ootani
هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا