41 research outputs found
Measurement of Carbon Disulfide Anion Diffusion in a TPC
A Negative Ion Time Projection Chamber was used to measure the field
dependence of lateral and longitudinal diffusion for CS anions drifting in
mixtures of CS and Ar at 40 Torr. Ion drift velocities and limits on the
capture distance for electrons as a function of field and gas mixture are also
reported.Comment: 10 pages, 5 figures, LaTeX using elsart.cl
Probing the structure of the cold dark matter halo with ancient mica
Mica can store (for >1 Gy) etchable tracks caused by atoms recoiling from
WIMPs. Ancient mica is a directional detector despite the complex motions it
makes with respect to the WIMP "wind". We can exploit the properties of
directionality and long integration time to probe for structure in the dark
matter halo of our galaxy. We compute a sample of possible signals in mica for
a plausible model of halo structure.Comment: 7 pages, 2 figure
Study of Negative-Ion TPC Using {\mu}-PIC for Directional Dark Matter Search
Negative-ion time projection chambers(TPCs) have been studied for low-rate
and high-resolution applications such as dark matter search experiments.
Recently, a full volume fiducialization in a self-triggering TPC was realized.
This innovative technology demonstrated a significant reduction in the
background with MWPC-TPCs. We studied negative-ion TPC using the {\mu}-PIC+GEM
system and obtained sufficient gas gain with CSgas and SF gas at
low pressures. We expect an improvement in detector sensitivity and angular
resolution with better electronics
Unique Signature of Dark Matter in Ancient Mica
Mica can store (for >1 Gy) etchable tracks caused by atoms recoiling from
WIMPs. Because a background from fission neutrons will eventually limit this
technique, a unique signature for WIMPs in ancient mica is needed. Our motion
around the center of the Galaxy causes WIMPs, unlike neutrons, to enter the
mica from a preferred direction on the sky. Mica is a directional detector and
despite the complex rotations that natural mica crystals make with respect to
this WIMP ``wind,'' there is a substantial dependence of etch pit density on
present day mica orientation.Comment: 5 pages, LaTeX, 2 figures. Accepted for publication at Phys. Rev.
Let
Dark sectors 2016 Workshop: community report
This report, based on the Dark Sectors workshop at SLAC in April 2016,
summarizes the scientific importance of searches for dark sector dark matter
and forces at masses beneath the weak-scale, the status of this broad
international field, the important milestones motivating future exploration,
and promising experimental opportunities to reach these milestones over the
next 5-10 years
US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report
This white paper summarizes the workshop "U.S. Cosmic Visions: New Ideas in
Dark Matter" held at University of Maryland on March 23-25, 2017.Comment: 102 pages + reference
Study of Negative-Ion TPC Using μ-PIC for Directional Dark Matter Search
Negative-ion time projection chambers(TPCs) have been studied for low-rate and high-resolution applications such as dark matter search experiments. Recently, a full volume fiducialization in a self-triggering TPC was realized. This innovative technology demonstrated a significant reduction in the background with MWPC-TPCs. We studied negative-ion TPC using the μ-PIC+GEM system and obtained sufficient gas gain with CS2 gas and SF6 gas at low pressures. We expect an improvement in detector sensitivity and angular resolution with better electronics