PRISMA Colloquium

Programm für das Sommersemester 2022

Wednesdays, 13:00 Uhr s.t.

Institut für Physik
Lorentz-Raum, 05-127, Staudingerweg 7

20.04.22Steen Hannestad, Univ. Aarhus, Denmark
CANCELED // Neutrino physics in the era of precision cosmology
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

27.04.22Almudena Arcones, TU Darmstadt
In 2017, a multimessenger era started with the first gravitational wave detection from the merger of two neutron stars (GW170817) and the rich electromagnetic follow-up. The most exciting electromagnetic counterpart was the kilonova. This provides an answer to the long-standing question of how and where heavy elements are produced in the universe. The neutron-rich material ejected during the neutron star merger (NSM) undergoes an r-process (rapid neutron capture process) that produces heavy elements and a kilonova. Moreover, observations of abundances from the oldest stars reveal an additional r-process contribution of a rare and fast event, which could be core-collapse supernovae (CCSN) with strong magnetic fields, so called magneto-rotational supernovae (MR-SN). Now we can use NSM and CCSN as cosmic laboratories to test nuclear physics under extreme conditions and to understand the origin and history of heavy elements. We combine hydrodynamic simulations of NSM and MR-SN including state-of-the-art microphysics, with nucleosynthesis calculations involving extreme neutron-rich nuclei, and forefront observations of stellar abundances in the Milky Way and in orbiting dwarf galaxies. This opens up a new frontier to use the freshly synthesized elements to benchmark simulations against observations. The nucleosynthesis depends on astrophysical conditions (e.g., mass of the neutron stars) and on the microphysics included (equation of state and neutrino interactions). Therefore, comparing calculated abundances based on simulations to observations of the oldest stars and future kilonovae will lead to ground-breaking discoveries for CCSN, NSM, the extreme physics involved, and the origin of heavy elements.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

04.05.22Geraldine Servant, DESY Hamburg
It is usually assumed that the axion starts oscillating around its minimum from its initially frozen position. However, the early dynamics of the Peccei-Quinn field can induce a large kinetic energy in the axion field, which starts rotating during its early evolution, before it gets trapped in one minimum. This can modify the equation of state of the universe by triggering a kination era before the axion acquires its mass. This imprints a smoking-gun gravitational-wave peak on the primordial gravitational-wave background in the sensitivity bands of LISA, ET, and CE. Future gravitational-wave observatories will thus offer a new window on axion models. I will present explicit realisations. I will also discuss how this dynamics opens up the allowed parameter space for ALP dark matter and other observational consequences.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

11.05.22Adi Bornheim, Caltech Pasadena, USA
Current and future high energy physics particle colliders can provide instantaneous luminosities of 10^34 cm-2s-1 and above. The high center of mass energy of 10 TeV and beyond, the large number of simultaneous collisions of beam particles in the experiments and the very high beam crossing rates pose significant challenges. At the same time, the breadth of physics studies carried out at these colliders is expanding continuously, ranging from searches over precision physics measurements to heavy ion physics. To detect and reconstruct physics events, the detectors must maximize the information they capture on the final state particles. Adi Bornheim will discuss how timing information with a precision of around a few 10 ps can aid the reconstruction of the physics events under such challenging conditions. He will present how the CMS detector operating at the LHC in CERN will be upgraded to exploit the precision timing capabilities of the calorimeter and by the inclusion of a dedicated MIP timing detector.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

18.05.22Chris Hays, Oxford, England
The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After the observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 TeV center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

25.05.22Mark Hindmarsh, Univ. Helsinki; Finland
Gravitational waves will be an important probe of physics beyond the Standard Model, as they would be produced at possible first order phase transitions in the early universe. I will discuss the characteristic spectrum of gravitational radiation from phase transitions, how it is connected to underlying physics, and prospects for probing physics beyond the Standard Model at the future space-based gravitational wave detector LISA.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

01.06.22Anke Biekötter, IPPP Durham, England
We have plenty of reasons to believe that there is physics beyond the Standard Model of particle physics. Currently, however, new fundamental physics is doing a very good job at hiding from us at high-energy experiments like the Large Hadron Collider (LHC) at CERN. The reason for this could be that potential new particles are too heavy to be directly detected at present experiments. In this talk, we will use effective field theory to describe the effects of heavy new fundamental physics at lower energy scales. Specifically, we will investigate what we can learn about new physics through a global analysis of LHC data.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

08.06.22Christian Ospelkaus, Univ. Hannover
Laser cooling and state manipulation are key techniques in modern-day atomic and molecular physics experiments, both for fundamental tests and quantum technology applications. While laser cooling was initially demonstrated in a Penning trap, it has seen relatively little use in Penning-trap precision measurements. Present-day Penning trap mass and g-factor precision measurements are now at a level where laser cooling and control can provide critical advances both for measurement speed and accuracy. Yet most species of interest in Penning trap precision measurements do not possess suitable internal structure for laser manipulation. A particularly challenging and rewarding system is the (anti-)proton, which is being investigated by precision experiments within the BASE collaboration. In this and similar cases, hybrid approaches are highly desirable, where a laser-cooled ion with well-known internal structure is used to control the particle of interest. As part of BASE, we are setting up a cryogenic Penning trap apparatus for sympathetic cooling of single (anti-)protons by laser-cooled 9Be+ ions. We discuss how quantum logic spectroscopy, as first proposed by Heinzen and Wineland in 1990 and first used in the context of single-ion optical clocks, can be implemented in this system, and present both sympathetic cooling and state manipulation techniques. We discuss our most recent experimental results, demonstrating ground state cooling of the 9Be+ ion in the Penning trap as the key enabling step for any quantum logic based state manipulation of (anti-)protons.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

15.06.22Ekkehard Peik, PTB Braunschweig
We use frequency comparisons between highly accurate optical clocks for tests of fundamental principles. In particular, the 171Yb+ optical clock based on an electric octupole transition between the S-ground state and the lowest excited F-level with a radiative lifetime of 1.58 years provides a favorable combination of low systematic uncertainty and high sensitivity to relativistic effects and potentially new physics. Using this system we have established improved limits for violations of local position invariance (in space and time), including the presently most stringent limits for temporal variations of the fine structure constant and the electron-proton mass ratio. I will give an outlook on the development of a 229Th nuclear optical clock that will open new perspectives for fundamental tests in the domain of nuclear physics.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

22.06.22Clara Cuesta, CIEMAT Madrid, Spain
The combined result of a number of experiments demonstrated that neutrinos have mass and oscillate. However fundamental questions about neutrinos remain: Is the neutrino its own antiparticle? What is the absolute scale of neutrino masses? How are the three neutrino mass states ordered? Is the CP symmetry violated in the neutrino sector? Are there sterile neutrino species? Current and future neutrino experiments are designed with state-of-the-art technology to provide answers to these questions. In this colloquium, the status of two of these experiments will be presented. On one hand, the Deep Underground Neutrino Experiment (DUNE) is a next generation experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and beyond the standard model searches. DUNE will consist of a beam of neutrinos located at Fermilab (US), a near detector, and a far detector placed at Sanford Underground Research Facility 1,300 km away. The far detector will have a total mass of 70 kton of liquid argon and as a previous step the ProtoDUNE program is on-going at the CERN Neutrino Platform. On the other hand, the MAJORANA DEMONSTRATOR operated an array of germanium detectors searching for neutrinoless double-beta decay (0𝜈𝛽𝛽). The excellent performance of the detectors provided new exclusion limits on the searches for neutrinoless double-beta decay and other rare-events, such as dark matter and axions.
Slides here...
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

zukünftige Termine
29.06.22Helene Götschel, FU Berlin
Physics and astrophysics are strongly aligned with cleverness and masculinity. ‘Not surprisingly, physics does an extremely good job at keeping people out’ (Anna Danielsson 2022). Therefore, encouraging women and minorities to join is not enough. We need to understand and overcome the gendered, classed and raced politics of knowledge-producing processes in STEM. In this talk we reflect on the power of norms and exclusions in the culture, representation, and teaching of physics. We look, for example, at communications in research labs, educational settings at universities, physicists’ behavior at conferences, and contents of physics textbooks. In addition, we discuss strategies to value and welcome diversity and equity in physics (teaching).
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

06.07.22Claude Duhr, Univ. Bonn
From geometry to precision physics
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

13.07.22Anna Sótér, ETH Zürich, Switzerland
Precision particle physics with exotic atoms and antimatter
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

20.07.22Christoph Langenbruch, RWTH Aachen
Flavour anomalies: Status and prospects
13:00 Uhr s.t., Lorentz-Raum, 05-127, Staudingerweg 7

Slides can be found on iAnnounce (https://iannounce.physik.uni-mainz.de/meeting/user/series/19) in each seminar's page under 'Attachments'.

Koordination: Kontakt:

Prof. Dr. Tobias Hurth
Institut für Physik, THEP
hurth@uni-mainz.de

Dr. Renée Dillinger-Reiter
renee.dillinger@uni-mainz.de