In many rare event searches noble gases are used as detector target. In order to achieve high sensitivities, the target material needs to be continuously circulated and cleaned from impurities and radioactive contaminants. To pump and compress xenon gas through such systems an ultra-clean, hermetically sealed, radon-free pump without oil lubrication is indispensable. Taking into account the...
LUX-ZEPLIN (LZ) is a dark matter direct detection experiment consisting of a dual-phase xenon time projection chamber with an active mass of 7 tonnes, which is surrounded by a xenon skin region and liquid scintillator to serve as active vetoes for gamma-ray and neutron backgrounds, respectively. With an extensive material assay effort, xenon purification campaign, and detector assembly under...
COSINUS is devoted to the study of the nature of the signal detected by the DAMA/LIBRA experiment and aims to definitely establish if the observed annually modulated signal is or is not a dark matter signature. The benefit of the technique employed by COSINUS, which develops cryogenic scintillating calorimeters with NaI-absorbers equipped with TES thermometers, consists in the event-by-event...
For over twenty-five years the DAMA/LIBRA (formerly DAMA/NaI) experiment has observed an annual modulation signal that is consistent with a dark matter explanation. This signal is, currently, in tension with the null results observed by other searches that utilize different target detectors. The COSINUS experiment will perform a model-independent cross-check of the DAMA/LIBRA result by using...
We use a combination of density functional and effective field theories to calculate the electronic structure of materials that are promising detectors for light dark matter and to predict the corresponding signal rates. Since light dark matter particles are more likely to interact with electrons in materials than to kinematically excite the atomic nuclei that were the focus of searches to...
The Hyper-Kamiokande (HyperK) experiment, currently under construction, is expected to conduct precise measurements of the Diffuse Supernova Neutrino Background (DSNB). This requires all backgrounds to be well understood. A possible source of background that has not been considered so far is that from sub-GeV dark matter (DM) which annihilates into neutrinos. We conduct dedicated...
CaWO4 is a well known target material for the search for Dark Matter (DM) via nuclear recoils caused by the scattering of potential DM particles. It was established as such and is famously used by the CRESST experiment, which has a detection sensitivity down to the 20 eV-scale for nuclear recoils. At this energy scale, a reliable simulation of the signal and its background is...
There are various mechanisms by which energy can be accumulated and stored in materials and later released. Examples include thermally induced luminescence and delayed luminescence/after-luminescence in many materials. Interactions between excitations, defects, or other configurations carrying excess energy can lead to avalanche relaxation or other effects, from small correlations in photon or...
The XENON Dark Matter Project uses a dual phase time projection chamber filled with liquid xenon to search for Dark Matter in the form of weakly interacting massive particles (WIMPs). The current iteration, the XENONnT experiment with 8.6 t of xenon, is taking science data and will also allow the investigation of other science topics due to its extremely low background especially for low...
In the search for dark matter particle candidates, the mass region below 1 GeV/c2 is mainly unprobed. Utilizing a low-noise silicon sensor as sensitive volume, we aim to detect the signal from an inelastic scattering between such a particle and a bound electron within the silicon. As the deposited energy is only a few eV of energy, a sensor capable of detecting such low signals is required. We...
The most massive satellite galaxy of the Milky Way (MW) is the Large Magellanic Cloud (LMC) at a distance of roughly 50 kpc. Parent and satellite galaxy form a dynamical system in which gravitational interactions induce non-equilibrium effects and features that alter the equilibrium expectations for the morphology of the dark matter (DM) halos hosting the baryonic components of both objects....
LUX-ZEPLIN (LZ) is a dual-phase xenon time projection chamber (TPC) designed to achieve sensitivity to a WIMP-nucleon spin-independent cross section of 1.4 × 10−48 cm^2 at a WIMP mass of 40GeV/c^2 after a livetime of 1000 live days. One of the key strengths of a dual-phase TPC is the use of both an electroluminescence and scintillation signal to discriminate signal from background, as well as...
Experimentalists strive to better analyse signals of dark matter direct detection at detectors. Thus, improved theoretical models are being developed to describe WIMP-nucleus elastic scattering. Notably, the work of Fitzpatrick et al [1,2] utilises an extended list of non-relativistic effective field theory (EFT) nuclear operators. We build on this work by investigating the sensitivity of said...
A main goal of current low background physics is the search for rare and novel phenomena beyond the Standard Model of particle physics. The researched processes are for example the scattering off of a potential Dark Matter particle inside a CaWO4 crystal of the CRESST experiment or the neutrinoless double beta decay of Ge nucleus for the future Legend experiment. Success of such experiments...
With much of the dark matter candidate parameter space still unexplored, novel detection technologies enable searches for previously inaccessible viable candidates. In particular, methods which exploit directional discrimination will allow for unambiguous confirmation of a galactic signal. Nano- and micro-particles, cooled and levitated in isolation within high vacuum, open up the potential...
Whereas weakly interacting massive particles (WIMPs) - a promising DM candidate - were intensively studied in the past, the theory of strongly interacting massive particles (SIMPs) has been comparably less investigated. A possible way to generate such SIMPs is through chiral symmetry breaking, similar to the production of pions in QCD. We consider a dark gauge group $\text{Sp}(4)$ and $N_f=2$...
We study the relic abundances of stable particles from a generic dark sector in the presence and absence of initial dark asymmetries, and find out that abundances are expected to be of similar magnitude, i.e. multi-component dark matter is quite natural. We first discuss the different possibilities for stabilizing multi-component dark matter and then analyze the final relic abundances of the...
The CRESST-III experiment specialises on the direct search for low-mass dark matter. The analysis of the CaWO4 detector called “detector A”, operated in Run34, provided world-leading limits in the sub- GeV mass range. To interpret the residually observed events, the existence of a background model is crucial. Neutron-induced nuclear recoils are similar to the sought-for DM-induced nuclear...
Paleo-detectors are a proposed alternative approach to the direct detection of Dark Matter. In lieu of using large target masses to search for nuclear recoils in real time, the idea behind paleo detectors is to use small detectors that could integrate signals from nuclear recoils over large timescales to achieve the necessary exposure for Dark Matter searches. Natural minerals found on Earth...
The DAMA experiments have detected a modulating signal compatible with dark matter for 20 years with a combined significance of 12.9 sigma. A result in tension for a spin independent WIMP with null results from large noble gas experiments. This is the motivation for NaI(Tl) based replication studies of the DAMA experiment.
One of the biggest challenges facing these experiments is the low...
Travelling-wave kinetic inductance parametric amplifiers (KIPAs) are cryogenic quantum-noise limited devices with O(10) dB gain over an octave or more of bandwidth, making them well suited for microwave domain astroparticle measurements. We present results from an experiment coupling a 4-8 GHz KIPA to a dish and antenna system to search for hidden-photon dark matter candidates. A cryogenically...
Dark matter (DM) accounts for 85% of the matter in our universe, however, its nature is still one of the biggest open questions in modern physics. While measurements have imposed strong limits on the spin-independent scattering of DM in direct detection experiments, the parameter space of spin-dependent scattering still leaves room for exploration. CRESST-III operated in their latest run for...
Construction of the COSINUS experiment is quickly progressing at the LNGS underground laboratory. In this contribution, we will present the experimental setup of the COSINUS rare event search, which aims at providing a crosscheck of the signal reported by the DAMA/LIBRA collaboration using NaI as a cryogenic absorber material. The scintillating bolometers of COSINUS will be operated in a dry...
In this study, we calculated the effect of self-interacting dark matter on neutron stars. Properties like the mass, radius and the tidal deformability are affected by the presence of dark matter in neutron stars. We show that the Love number can be used to probe the presence and the properties of dark matter inside of neutron stars in future gravitational wave measurements.
Large efforts are being made to directly detect interactions of Dark Matter with ordinary matter, including the Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) experiment located at the Labor- atori Nazionali del Gran Sasso (LNGS) in Italy. During the second phase of the experiment, CRESST-II, scin- tillating CaWO4 target crystals were used to detect nuclear recoils....
Warm dark matter (WDM) could explain some small-scale structure observations that have challenged the cold dark matter (CDM) model, as warm particles suppress structure formation due to free streaming effects. Observing small-scale structure thus provides a valuable way to distinguish between CDM and WDM. In this talk, I will present a semi-analytical model of the dark matter substructure...
Dual-phase noble liquid time-projection chambers have a long application history in searches for rare low-energy events like interactions with dark matter particles. Because of scalability and existing support infrastructure, they are expected to serve in large future projects. Our analysis of data and models for electrons and ions extraction from the liquid into the gas phase and data for the...
