Conveners
Parallel 1C - Direct detection II
- Michelle Galloway (University of Zürich)
Parallel 1C - Direct detection II
- Elisabetta Baracchini
Sensitivity of underground experiments searching for rare events due to dark matter or neutrino interactions is often limited by the background caused by neutrons from spontaneous fission and (alpha,n) reactions. A number of codes exist to calculate neutron yields and energy spectra due to these processes. Here we present the calculations of neutron production using the modified SOURCES4 code...
Muon-induced neutrons can lead to potentially irreducible backgrounds in rare event search experiments. We have investigated the implication of laboratory depth on the muon induced background in a future dark matter experiment capable of reaching the so-called neutrino floor. Our simulation study focuses on a xenon-based detector with 70 tonnes of active mass, surrounded by additional veto...
DarkSide-20k is a direct dark matter search experiment, that looks for Weakly Interacting Massive Particles (WIMPs) events. The detector is based on an ultrapure liquid Argon double-phase Time Projection Chamber, which will be located at Laboratori Nazionali del Gran Sasso. In the rare event search experiments (like the DarkSide case), it is crucial to keep under control any background...
The gas SF$_6$ has become of interest as a negative ion drift gas for use in directional dark matter searches. However, as for other gas targets in such searches, it is important that contamination can be removed as problems with signal detection can arise. Radon gas contamination can decay and produce unwanted background events, able to mimic genuine signals. Outgassing and gas leakage from...
Radioactivity-induced backgrounds are one of the major sources of backgrounds for rare event search experiments like direct detection of Dark Matter, Coherent Elastic Neutrino Nucleus Scattering (CE$\nu$NS), and Neutrinoless Double Beta decay (NDBD). Measurement of these backgrounds and their reduction is crucial for these experiments. We will discuss the fabrication and performance of a newly...
The LUX-ZEPLIN (LZ) dark matter experiment consists of 7 active tonnes of liquid xenon sensitive to weakly interacting massive particles (WIMPs). Even with extensive radiopurity screening and shielding, such experiments still suffer from gamma-ray and neutron backgrounds from nearby material. Any excess detected in LZ requires a deep understanding of these backgrounds; for this purpose, we...
After many years of careful design and construction, the LUX-ZEPLIN (LZ) experiment is finally taking data. Located at the Sanford Underground Research Facility in Lead, South Dakota, LZ employs a dual-phase Time Projection Chamber to search for dark matter particles. With an active volume of 7 tonnes and a three-component veto system (xenon skin, gadolinium-loaded liquid scintillator outer...
Despite great efforts to directly detect dark matter (DM), experiments so far have found no evidence. The sensitivity of direct detection of DM approaches the so-called neutrino floor below which it is hard to disentangle the DM candidate from the background neutrino. One of the promising methods of overcoming this barrier is to utilize the directional signature that both neutrino- and...
The development of low-background anisotropic detectors can offer a unique way to study those Dark Matter (DM) candidate particles able to induce nuclear recoils through the directionality technique. This approach is based on studying the correlation between the nuclear recoil's direction and the Earth's motion in the galactic rest frame, thanks to the anisotropic features of such...
The threshold displacement energy for nuclear recoils depends strongly on the direction of the recoiling nucleus with respect to the crystal lattice. Assuming that similar dependence holds for the ionization threshold for low energy nuclear recoils, we explore the consequences of the resulting directional dependence of the observable event rate in ionization detectors. For low mass dark...
The last few years have seen the largest underground dark matter searches rapidly approach their purported ultimate sensitivity limit known as the neutrino floor, or increasingly, "neutrino fog". An experiment reaches the neutrino fog went it becomes so large and so sensitive that the background from the coherent scattering of astrophysical neutrinos begins to masquerade as dark matter,...
Levitated optomechanics provides a novel platform to test fundamental physics. One such application provides a unique directional dark matter direct detection technique to explore alternative parameter space to that being investigated by large scale experiments deployed underground. We present first results from our experiment, capable of resolving collisions in all three dimensions, utilising...
We are going to present the CYGNO project for the development of a high precision optical readout gaseous TPC for directional Dark Matter search and solar neutrino spectroscopy, to be hosted at Laboratori Nazionali del Gran Sasso. CYGNO (a CYGNus TPC with Optical readout) fits into the wider context of the CYGNUS proto-collaboration, for the development of a Galactic Nuclear Recoil Observatory...
Directional detection is the only admitted strategy for the unambiguous identification of galactic Dark Matter (DM) even in the presence of an irreducible background as beyond the neutrino floor. The directional detection strategy relies on the simultaneous measurements of the energy and the direction of a DM-induced nuclear recoil for identification of a DM particle without ambiguity. Recoil...
Conventional Dark Matter (DM) detectors are approaching the limitations of the neutrino floor, however DM searches with directional sensitivity offer the potential for probing beneath this neutrino background by measuring the galactic origin of Nuclear Recoil (NR) signals. CYGNUS is a global collaboration between several research groups with the common goal of building a galactic NR...
