Gamma-ray bursts (GRBs) are the strongest explosions in the Universe since the Big Bang. They are believed to be produced either in the formation of black holes at the end of massive star evolution or the merging of compact objects.
Solid deuterium (sD2) is used as an efficient converter to produce ultracold neutrons (UCN). Itis known that the sD2 must be sufficiently cold, of high purity and mostly in its ortho-state in order to guarantee long lifetimes of UCN in the solid from which they are extracted into vacuum.
The observation of Higgs boson production in association with a top quark-antiquark pair is reported, based on a combined analysis of proton-proton collision data at center-of-mass energies of √s = 7,8, and 13 TeV, corresponding to integrated luminosities of up to 5.1, 19.7, and 35.9 fb-1, respectively. The data were collected with the CMS detector at the CERN LHC.
In recent years, intriguing hints for the violation of lepton flavor universality (LFU) have been accumulated in semileptonic B decays, both in the charged-current transitions b → cl-ν-l (i.e., RD, RD∗, and RJ/Ψ and the neutral-current transitions b → sl+l- (i.e., RK and RK∗.
The Charpak-Ritz Prize 2018, jointly awarded by the French Physical Society and the Swiss Physical Society, has been bestowed to Roland Paul Horisberger for his numerous contributions to the development of precision silicon vertex detectors for particle physics experiments as well as for the application of these technologies in X-ray photon sciences.
Jean-Baptiste Mosset from the Laboratory of Particle Physics is the winner of a PSI Founder Fellowship and plans now to commercialise a neutron detector to spot plutonium and uranium. With his new technology, less expensive and more efficient neutron detectors could be developed. In the next 18 months, Mosset wants to further develop his prototype and find out if demand for this technology exists in industry.
We report on a search for ultralow-mass axionlike dark matter by analyzing the ratio of the spin-precession frequencies of stored ultracold neutrons and 199Hg atoms for an axion-induced oscillating electric dipole moment of the neutron and an axion-wind spin-precession effect. No signal consistent with dark matter is observed for the axion mass range 10-24 ≤ ma ≤ 10-17eV.
In the previous months the new CMS pixel detector was brought into operation. The detector was moved from PSI to CERN and installed in February, followed by an intensive period of commissioning and calibration. This process mostly involved the adjustment of many operational parameters which influence the detector performance, e.g.
Aldo Antognini a la physique et la convivialité dans le sangAldo Antognini, chercheur au PSI, a reçu plus de 2 200 000 francs de l’UE pour sa nouvelle expérience. Son objectif: déterminer la répartition du magnétisme dans le proton. Pour y arriver, ce physicien des particules devra mettre ses talents scientifiques et techniques à contribution, mais aussi son entregent.