The MIMAC experiment is a $mu$-TPC matrix project for directional dark matter search. Directional detection is a strategy based on the measurement of the WIMP flux anisotropy due to the solar system motion with respect to the dark matter halo. The ma
in purpose of MIMAC project is the measurement of the energy and the direction of nuclear recoils in 3D produced by elastic scattering of WIMPs. Since June 2012 a bi-chamber prototype is operating at the Modane underground laboratory. In this paper, we report the first ionization energy and 3D track observations of nuclear recoils produced by the radon progeny. This measurement shows the capability of the MIMAC detector and opens the possibility to explore the low energy recoil directionality signature.
Three-dimensional track reconstruction is a key issue for directional Dark Matter detection. It requires a precise knowledge of the electron drift velocity. Magboltz simulations are known to give a good evaluation of this parameter. However, large TP
C operated underground on long time scale may be characterized by an effective electron drift velocity that may differ from the value evaluated by simulation. In situ measurement of this key parameter is hence a way to avoid bias in the 3D track reconstruction. We present a dedicated method for the measurement of the electron drift velocity with the MIMAC detector. It is tested on two gas mixtures : $rm CF_4$ and $rm CF_4+CHF_3$. We also show that adding $rm CHF_3$ allows us to lower the electron drift velocity while keeping almost the same Fluorine content of the gas mixture.
Directional detection of non-baryonic Dark Matter is a promising search strategy for discriminating WIMP events from neutrons, the ultimate background for dark matter direct detection. This strategy requires both a precise measurement of the energy d
own to a few keV and 3D reconstruction of tracks down to a few mm. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of large pixelized micromegas with a special developed fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The first bi-chamber prototype has been installed at Modane, underground laboratory in June 2012. The first undergournd background events, the gain stability and calibration are shown. The first spectrum of nuclear recoils showing 3D tracks coming from the radon progeny is presented.
In order to measure the energy of neutron fields, with energy ranging from 8 keV to 1 MeV, a new primary standard is being developed at the IRSN (Institute for Radioprotection and Nuclear Safety). This project, micro-TPC (Micro Time Projection Chambe
r), carried out in collaboration with the LPSC (Laboratoire de Physique Subatomique et de Cosmologie), is based on the nuclear recoil detector principle. The instrument is presented with the associated method to measure the neutron energy. This article emphasizes the proton energy calibration procedure and energy measurements of a neutron field produced at 127 keV with the IRSN facility AMANDE.
The dark matter directional detection opens a new field in cosmology bringing the possibility to build a map of nuclear recoils that would be able to explore the galactic dark matter halo giving access to a particle characterization of such matter an
d the shape of the halo. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of large pixelized micromegas with a devoted fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The discovery potential of this search strategy is discussed and illustrated. In June 2012, the first bi-chamber prototype has been installed at Modane Underground Laboratory (LSM) and the first underground background events, the gain stability and calibration are shown.
Directional detection of non-baryonic DarkMatter is a promising search strategy for discriminating WIMP events from background ones. This strategy requires both a measurement of the recoil energy down to a few keV and 3D reconstruction of tracks down
to a few mm. The MIMAC project, based on a micro-TPC matrix, filled with CF4 and CHF3 is being developed. The first results of a chamber prototype of this matrix, on low energy nuclear recoils (1H and 19F) obtained with mono-energetic neutron fields are presented. The discovery potential of this search strategy is illustrated by a realistic case accessible to MIMAC.
A front end ASIC has been designed to equip the {mu}TPC prototype developed for the MIMAC project, which requires 3D reconstruction of low energy particle tracks in order to perform directional detection of galactic Dark Matter. Each ASIC is able to
monitor 64 strips of pixels and provides the Time Over Threshold information for each of those. These 64 digital informations, sampled at a rate of 50 MHz, can be transferred at 400MHz by eight LVDS serial links. Eight ASIC were validated on a 2x256 strips of pixels prototype.
There is considerable experimental effort dedicated to the directional detection of particle dark matter. Gaseous mu-TPC detectors present the privileged features of being able to reconstruct the track and the energy of the recoil nucleus following t
he interaction. A precise measurement of the recoil energy is a key point for the directional search strategy. Quenching has to be taken into account, i.e. only a certain fraction of the recoil energy is deposited in the ionization channel. Measurements of the ionization quenching factor for different gas mixture at room temperature have been made with a dedicated ion beam facility at the LPSC of Grenoble.
Directional detection of non-baryonic Dark Matter is a promising search strategy for discriminating WIMP events from background. However, this strategy requires both a precise measurement of the energy down to a few keV and 3D reconstruction of track
s down to a few mm. To achieve this goal, the MIMAC project has been developed. It is based on a gaseous micro-TPC matrix, filled with CF4 and CHF3. The first results on low energy nuclear recoils (H, F) obtained with a low mono-energetic neutron field are presented. The discovery potential of this search strategy is discussed and illustrated by a realistic case accessible to MIMAC.
Directional detection of non-baryonic Dark Matter is a promising search strategy for discriminating WIMP events from background. However, this strategy requires both a precise measurement of the energy down to a few keV and 3D reconstruction of track
s down to a few mm. To achieve this goal, the MIMAC project has been developed. It is based on a gaseous micro-TPC matrix, filled with 3He, CF4 and/or C4H10. The first results on low energy nuclear recoils (1H and 19F) obtained with a low mono-energetic neutron field are presented. The discovery potential of this search strategy is discussed and illustrated by a realistic case accessible to MIMAC.
