Experimental Particle and Astro-Particle Physics Seminar

Modeling gravitational wave signals from compact binaries

In the upcoming observational  runs of the ground-based detectors, computationally efficient Inspiral-Merger-Ringdown waveform models for compact binaries coalescing along quasi-eccentric orbits will be important tools for gravitational-wave data analysis. Accurate, ready-to-use Fourier-domain eccentric inspiral templates are a crucial ingredient for the modeling of such waveform families. I will present on-going efforts to compute amplitude-corrected analytic Fourier-domain gravitational waveforms that incorporate effects of periastron advance and gravitational wave emission in the evolution of eccentric orbits. Additionally, I will report on nascent efforts to distinguish neutron star-neutron star binaries from black hole-neutron star systems through gravitational-wave observations of their inspiral.

Clara Matteuzzi
(University Milano-Bicocca)

Measuring the hadronic contributions to the muon (g-2) through elastic scattering of muons on electrons

The discrepancy between the experimental value and the Standard Model (SM) prediction of the anomalous magnetic moment (g-2) of the muon, amounts, depending on the theoretical approach, to between 3.5 and 4 standard deviations. The experimental value  of the muon g-2, is going to be updated at Fermilab and at JPARC, with experiments aiming at improving the uncertainty by a factor ~4 with respect to the previous measurements. The most significant contribution to the theoretical error of the SM prediction comes from the calculation of the effects of hadronic contributions to the running of the electromagnetic coupling constant. We propose a new method to determine the leading order hadronic contribution by measuring the effective electromagnetic coupling constant in the space-like region by means of the elastic muon-electron scattering data collected at a fixed target experiment. Although challenging, this measurement will open the possibility to test the internal consistency of the SM at the level of quantum corrections with unprecedented precision and to possibly establish the presence of New Physics phenomena through virtual effects.

Dirk Wiedner

(Universität Heidelberg)

High Voltage Monolithic Active Pixel Sensors for the Mu3e experiment

Prof. Riccardo Catena
(Chalmers University Göteborg)

Constraining the dark matter particle spin with direct detection experiments 

One of the major challenges in modern physics is to unravel the mystery that surrounds Dark Matter (DM) – the invisible mass in our Universe.  One leading hypothesis is that DM consists of yet undetected particles called WIMPs (for Weakly Interacting Massive Particles).  WIMPs are expected to be in thermal equilibrium with the other species in the early Universe, and interact with ordinary matter through weak scale interactions. If the hypothesis is correct, WIMPs might soon be detected with existing experimental techniques. This makes the development of  WIMP data interpretation strategies a priority in the field. However, current strategies to interpret a hypothetical WIMP signal would only allow to determine DM mass and coupling constants, while leaving the WIMP spin unconstrained. This is a serious limitation, since WIMP statistics and interactions strongly depend upon spin. In this talk I will present methods to extract information on the DM particle spin from a hypothetical WIMP signal at direct detection experiments searching for nuclear recoils induced by the scattering of Milky Way DM particles in low-background detectors. 

Verena Meyer - Physikerin, Rektorin, Präsidentin des Wissenschaftsrats

see https://www.physik.uzh.ch/schroedinger/ for details

Laura Baudis, Florencia Canelli

Alison Mitchell
(University of Zurich)

Very High Energy Gamma-ray Astronomy and Extensive Air Showers with IACTs

Imaging Atmospheric Cherenkov Telescopes (IACTs) use the Cherenkov radiation produced by Extensive Air Showers (EAS) within the atmosphere to study gamma-rays and cosmic rays. In this talk, I will present results of a detailed analysis of the pulsar wind nebula HESS J1825-137 using H.E.S.S., an array of five IACTs located in Namibia. This analysis enables properties of the particle transport within the nebula to be constrained. In addition to leptonic EAS generated by gamma-rays, IACTs also detect Cherenkov light from cosmic-ray initiated hadronic EAS. Muons produced within hadronic EAS are easily identifiable and usually used for calibration of IACTs. I will present the potential of IACTs to measure properties of muons within TeV EAS, including parameters of interest to current hadronic interaction models. An outlook to the future Cherenkov Telescope Array (CTA) will be given. 

Prof. Chiara Macchiavell

Entanglement, complementarity and correlations

see https://www.physik.uzh.ch/schroedinger/ for details

How to build your own neutrino oscillation experiment (and what you will get out of it)

I will describe the basic elements of a neutrino oscillation experiment from the beam to the neutrino detection paying attention to the challenges they bring from
the hardware to the physics knowledge.  I will describe the main source of systematic errors and how the community is addressing them. I will be using the T2K experiment as a drive line through the talk but paying attention to future experiments such as Dune and HK, and how they will be addressing those challenges. I will devote some time also to explain in a critical way the latest results and what we might expect in the future and how the synergy of the different results will help in shaping the future.