Riding the dark matter wave: Novel limits on general dark photons from LISA Pathfinder

We note the possibility to perform a parametrically improved search for gauged baryon (B) and baryon minus lepton ($B-L$) Dark Photon Dark Matter (DPDM) using auxiliary channel data from LISA Pathfinder. In particular we use the measurement of the differential movement between the test masses (TMs) and the space craft (SC) which is nearly as sensitive as the tracking between the two TMs. TMs and SC are made from different materials and therefore have different charge-to-mass ratios for both $B-L$ and B. Thus, the surrounding DPDM field induces a relative acceleration of nearly constant frequency. For the case of $B-L$, we find that LISA Pathfinder can constrain previously unexplored parameter space, providing the world leading limits in the mass range $4\cdot10^{-19}\space{eV}<m<3\cdot10^{-17}\space{eV}$. This limit can easily be recast also for dark photons that arise from gauging other global symmetries of the SM

Light-shining-through The Dark Side of the Moon

The dark photon (DP) is a simple and well-motivated candidate for BSM physics. For keV masses or lighter, the sun can potentially produce a large flux of these particles which can be searched for by so-called helioscopes. In this talk, I will discuss the impact of the angular and spectral distribution of solar DPs on these searches. Considering calibration images of the HINODE XRT solar x-ray telescope one can use its precise angular resolution to improve on previous helioscope analysis techniques which were based on pure event counting. I will show that the use of the additional information can boost the constraints by around one order of magnitude. For this, I will also briefly discuss a reevaluation of the literature results on the angular distribution of DPs. Furthermore, I will comment on the use of solar eclipses as exceptionally large helioscopes. Due to the small exposure, these constraints cannot compete with the current searches of transversal DPs and they require a more sophisticated background modeling due to the pollution by real solar x-rays from the corona

The ups and downs of inelastic dark matter - Electron recoils from terrestrial upscattering

The growing interest in the interactions between dark matter particles and electrons has received a further boost by the observation of an excess in electron recoil events in the XENON1T experiment. Of particular interest are dark matter models in which the scattering process is inelastic, such that the ground state can upscatter into an excited state. The subsequent exothermic downscattering of such excited states on electrons can lead to observable signals in direct detection experiments and gives a good fit to the XENON1T excess. In this talk, I will discuss terrestrial upscattering, i.e. inelastic scattering of dark matter particles on nuclei in the Earth, as a plausible origin of such excited states. I will demonstrate that both analytical and Monte Carlo methods allow for a detailed prediction of the excited density and velocity distribution. These results show a time dependence of the flux of excited states resulting from the rotation of the Earth. This daily modulation offers an intriguing opportunity to distinguish this mechanism from alternative explanations of the XENON1T excess and to additionally determine the DM mass.This talk will be based on https://arxiv.org/abs/2112.06930

iDM@IDM: Electron recoils from terrestrial upscattering of inelastic dark matter - Electron recoils from terrestrial upscattering

The growing interest in the interactions between dark matter particles and electrons has received a further boost by the observation of an excess in electron recoil events in the XENON1T experiment. Of particular interest are dark matter models in which the scattering process is inelastic, such that the ground state can upscatter into an excited state. The subsequent exothermic downscattering of such excited states on electrons can lead to observable signals in direct detection experiments and gives a good fit to the XENON1T excess. In this talk, I will discuss terrestrial upscattering, i.e. inelastic scattering of dark matter particles on nuclei in the Earth, as a plausible origin of such excited states. I will demonstrate that both analytical and Monte Carlo methods allow for a detailed prediction of the excited density and velocity distribution. These results show a time dependence of the flux of excited states resulting from the rotation of the Earth. This daily modulation offers an intriguing opportunity to distinguish this mechanism from alternative explanations of the XENON1T excess and to additionally determine the DM mass.This talk will be based on https://arxiv.org/abs/2112.06930