לוח שנה משולב

Today, many observations on various astronomical scales provide compelling evidence for the existence of dark matter. Its underlying nature, however, remains an open question of present-day physics.
The CRESST experiment is a direct dark matter search which aims to measure interactions of potential dark matter particles in an earth-bound detector, using scintillating CaWO4 crystals as target material operated as cryogenic calorimeters at millikelvin temperatures. Each interaction in CaWO4 produces a phonon signal in the target crystal and also a light signal that is measured by a secondary cryogenic calorimeter. This technology is particularly sensitive to small energy deposits induced by light dark matter particles, allowing the experiment to probe the low-mass region of the parameter space for spin-independent dark matter-nucleon scattering with high sensitivity.
Results obtained in the first run of CRESST-III with a detector achieving a nuclear recoil threshold of 30.1 eV, probing dark matter particle masses down to 0.16 GeV/c2, will be presented.

In order to infect and persist in their hosts, viruses utilize multiple strategies to evade the immune system. HIV utilizes membrane interacting regions of its envelope protein, primarily used to fuse with its target cells, to inhibit T-cell activation. Yet, it is unknown whether this ability is shared with other viruses. We examined the T-cell inhibitory activity of HTLV-1, focusing on a functionally conserved region of HTLV’s and HIV’s fusion proteins, the fusion peptide (FP). Here, we reveal that HTLV’s FP modulates T-cell activity in-vitro and in-vivo. This modulation is characterized by downregulation of the Th1-response, leading to an elevated Th2-response observed by transition in mRNA, cytokines and regulatory proteins. Our findings suggest that FP mediated immune evasion might be a trait shared between different viruses.

The Center of our Galaxy is a unique laboratory for exploring the astrophysics around a massive black hole and testing General Relativity in this extreme environment. I will discuss the results of a major campaign of observing the Galactic Center in 2017/2018 with three instruments at the European Southern Observatory's VLT, including the novel GRAVITY interferometric beam combiner of the four 8-meter telescopes. During this period the B-star S2 completed a peri-passage at ~1400 Schwarzschild radii around the compact radio source SgrA*, and permitted for the first time a test of the equivalence principle and the detection of the first post-Newtonian orbital elements in a classical 'clock experiment' around a massive black hole. During bright states (

Since the isolation of graphene in 2004, atomically-thin quasi-two-dimensional (quasi-2D) materials have proven to be an exciting platform for both applications in novel devices and exploring fundamental phenomena arising in low dimensions. This interesting low-dimensional behavior is a consequence of the combined effects of quantum confinement and stronger electron-electron correlations due to reduced screening. In this talk, I will discuss how the optical excitations (excitons) in quasi-2D materials, such as monolayer transition metal dichalcogenides and few-layer black phosphorus, differ from typical bulk materials. In particular, quasi-2D materials are host to a wide-variety of strongly-bound excitons with unusual excitation spectra and massless dispersion. The presence of these excitons can greatly enhance both linear and nonlinear response compared to bulk materials, making them ideal candidates for optoelectronics and energy applications. Moreover, due to enhanced correlations and environmental sensitivity, the electronic and optical properties of these materials can be easily tuned. I will discuss how substrate engineering, stacking of different layers, and the introduction or removal of defects can be used to tune the band gaps and optical selection rules in quasi-2D materials.