919 research outputs found
A review on the discovery reach of Dark Matter directional detection
Directional detection of galactic Dark Matter offers a unique opportunity to
identify Weakly Interacting Massive Particle (WIMP) events as such. Depending
on the unknown WIMP-nucleon cross section, directional detection may be used to
: exclude Dark Matter, discover galactic Dark Matter with a high significance
or constrain WIMP and halo properties. We review the discovery reach of Dark
Matter directional detection.Comment: Proceedings of the 4th international conference on Directional
Detection of Dark Matter (CYGNUS 2013), 10-12 June 2013, Toyama, Japa
Identification of Dark Matter with directional detection
Directional detection is a promising search strategy to discover galactic
Dark Matter. Taking advantage on the rotation of the Solar system around the
Galactic center through the Dark Matter halo, it allows to show a direction
dependence of WIMP events. Data of directional detectors are composed of energy
and a 3D track for each recoiling nuclei. Here, we present a Bayesian analysis
method dedicated to data from upcoming directional detectors. However, we focus
only on the angular part of the event distribution, arguing that the energy
part of the background distribution is unknown. Two different cases are
considered: a positive or a null detection of Dark Matter. In the first
scenario, we will present a map-based likelihood method allowing to recover the
main incoming direction of the signal and its significance, thus proving its
Galactic origin. In the second scenario, a new statistical method is proposed.
It is based on an extended likelihood in order to set robust and competitive
exclusion limits. This method has been compared to two other methods and has
been shown to be optimal in any detector configurations. Eventually, prospects
for the MIMAC project are presented in the case of a 10 kg CF4 detector with an
exposition time of 3 years.Comment: Proceeding of the 8th International Workshop on the Identification of
Dark Matter (IDM 2010), July 2010, Montpellier, France. To appear in
Proceedings of Science (PoS
Directional detection of galactic dark matter
Directional detection is a promising Dark Matter search strategy. Taking
advantage on the rotation of the Solar system around the galactic center
through the Dark Matter halo, it allows to show a direction dependence of WIMP
events that may be a powerful tool to identify genuine WIMP events as such.
Directional detection strategy requires the simultaneous measurement of the
energy and the 3D track of low energy recoils, which is a common challenge for
all current projects of directional detectors.Comment: Proceedings of UCLA Dark Matter 2012, 10th Symposium on Sources and
Detection of Dark Matter and Dark Energy in the Universe, Marina del Rey
Marriott, CA, USA, February 22-24, 201
An analysis method for time ordered data processing of Dark Matter experiments
The analysis of the time ordered data of Dark Matter experiments is becoming
more and more challenging with the increase of sensitivity in the ongoing and
forthcoming projects. Combined with the well-known level of background events,
this leads to a rather high level of pile-up in the data. Ionization,
scintillation as well as bolometric signals present common features in their
acquisition timeline: low frequency baselines, random gaussian noise, parasitic
noise and signal characterized by well-defined peaks. In particular, in the
case of long-lasting signals such as bolometric ones, the pile-up of events may
lead to an inaccurate reconstruction of the physical signal (misidentification
as well as fake events). We present a general method to detect and extract
signals in noisy data with a high pile-up rate and qe show that events from few
keV to hundreds of keV can be reconstructed in time ordered data presenting a
high pile-up rate. This method is based on an iterative detection and fitting
procedure combined with prior wavelet-based denoising of the data and baseline
subtraction. {We have tested this method on simulated data of the MACHe3
prototype experiment and shown that the iterative fitting procedure allows us
to recover the lowest energy events, of the order of a few keV, in the presence
of background signals from a few to hundreds of keV. Finally we applied this
method to the recent MACHe3 data to successfully measure the spectrum of
conversion electrons from Co57 source and also the spectrum of the background
cosmic muons
Directional Detection of Dark Matter with MIMAC
Directional detection is a promising search strategy to discover galactic
Dark Matter. We present a Bayesian analysis framework dedicated to Dark Matter
phenomenology using directional detection. The interest of directional
detection as a powerful tool to set exclusion limits, to authentify a Dark
Matter detection or to constrain the Dark Matter properties, both from particle
physics and galactic halo physics, will be demonstrated. However, such results
need highly accurate track reconstruction which should be reachable by the
MIMAC detector using a dedicated readout combined with a likelihood analysis of
recoiling nuclei.Comment: 4 pages, 2 figures, to appear in the proceedings of the TAUP 2011
conference held in Munich (5 - 9 September, 2011
MIMAC-He3 : A Micro-TPC Matrix of Chambers of He3 for direct detection of Wimps
The project of a micro-TPC matrix of chambers of \hetrois for direct
detection of non-baryonic dark matter is presented. The privileged properties
of He3 are highlighted. The double detection (ionization - projection of
tracks) is explained and its rejection evaluated. The potentialities of
MIMAC-He3 for supersymmetric dark matter search are discussed.Comment: to appear in Proc. of the 9th International Conference on Topics in
Astroparticle and Underground Physics (TAUP 2005), Zaragoza, Sept. 200
GePEToS : A Geant4 Monte Carlo simulation package for Positron Emission Tomography
GePEToS is a simulation framework developed over the last few years for
assessing the instrumental performance of future PET scanners. It is based on
Geant4, written in Object-Oriented C++ and runs on Linux platforms. The
validity of GePEToS has been tested on the well-known Siemens ECAT EXACT HR+
camera. The results of two application examples are presented : the design
optimization of a liquid Xe micro-PET camera dedicated to small animal imaging
as well as the evaluation of the effect of a strong axial magnetic field on the
image resolution of a Concorde P4 micro-PET camera.Comment: 5 pages, 12 figures, submitted to IEEE Transactions on Nuclear
Scienc
Track reconstruction with MIMAC
Directional detection of Dark Matter is a promising search strategy. However,
to perform such kind of detection, the recoiling tracks have to be accurately
reconstructed: direction, sense and position in the detector volume. In order
to optimize the track reconstruction and to fully exploit the data from the
MIMAC detector, we developed a likelihood method dedicated to the track
reconstruction. This likelihood approach requires a full simulation of track
measurements with MIMAC in order to compare real tracks to simulated ones.
Finally, we found that the MIMAC detector should have the required performance
to perform a competitive directional detection of Dark Matter.Comment: 9 pages, 6 figures; Proceedings of the 3rd International conference
on Directional Detection of Dark Matter (CYGNUS 2011), Aussois, France, 8-10
June 201
Bolometric calibration of a superfluid He detector for Dark Matter search: direct measurement of the scintillated energy fraction for neutron, electron and muon events
We report on the calibration of a superfluid He bolometer developed for
the search of non-baryonic Dark Matter. Precise thermometry is achieved by the
direct measurement of thermal excitations using Vibrating Wire Resonators
(VWRs). The heating pulses for calibration were produced by the direct quantum
process of quasiparticle generation by other VWRs present. The bolometric
calibration factor is analyzed as a function of temperature and excitation
level of the sensing VWR. The calibration is compared to bolometric
measurements of the nuclear neutron capture reaction and heat depositions by
cosmic muons and low energy electrons. The comparison allows a quantitative
estimation of the ultra-violet scintillation rate of irradiated helium,
demonstrating the possibility of efficient electron recoil event rejection.Comment: 17 pages, submitted to Nuc. Instr. Meth.
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