Thema: 
Molecularlevel ionizingradiation matter interactions and their consequences 
Datum: 
13.12.22 
Uhrzeit: 
14:15 
Ort: 
H6 
Vortragender: 

Universität Kassel 

Inhalt: 
The interaction between ionizing electromagnetic radiation and dense matter and processes following an initial ionization event are fundamental to a variety of important challenges in society and science. If those processes would be fully understood, this could be the basis to develop measures to avoid or cure hazardous effects due to ionizingradiation exposure of biologically relevant systems, to develop treatments for diseases occurring as consequences of such processes in living entities, or, in a completely different field of science, to understand fundamental processes in astrochemistry. In the presentation I will show how spectroscopy of dispersed fluorescence, electrons and by multicoincidence methods upon ionization by monochromatized synchrotron and freeelectron laser radiation can be used to clarify and quantify those fundamental processes. By increasing the complexity of the investigated systems stepwise from photoionization and photodissociation processes of individual atoms or molecules over processes occurring in clusters towards processes occurring in liquids my group tries to investigate how processes essentially known to us in individual molecules may be changed and which other processes may occur when those molecules are embedded in (approximately) realistic environments. 
Ansprechpartner: 
Thema: 
tba 
Datum: 
13.01.23 
Uhrzeit: 
16:15 
Ort: 
D5153 
Vortragender: 

Universität Regensburg 

Inhalt: 

Ansprechpartner: 
Thema: 
Relativistic dynamics in black hole systems and efforts toward the discovery of nanoHz GWs 
Datum: 
12.12.22 
Uhrzeit: 
16:15 
Ort: 
D6135 
Vortragender: 

TIFR Mumbai 

Inhalt: 
The study of bound particle trajectories around a rotating black hole is crucial to understanding many as trophysical phenomena. I will present a new closedform analytic solution for the generalized nonequatorial eccentric bound particle trajectories, and their fundamental frequencies, in the Kerr spacetime using general relativity. The trajectories are expressed in the eccentricity, inverselatus rectum, spin, and Carter’s constant (e, ?, a, Q) parameter space. The generalized solutions also enabled us to obtain the necessary bound orbit conditions for (e, ?, a, Q) and novel specialized formulae for equatorial, spherical, and nonequatorial sepa ratrix orbits. Next, I will present the Generalized Relativistic Precession Model (GRPM), which utilizes the analytic solutions of trajectories in the Kerr spacetime, to explain the origin of Quasiperiodic oscillations (QPOs) in black hole Xray binaries (BHXRB). Our analysis of the plasma fluid flow around a Kerr black hole in the relativistic disk edge suggests that instabilities cause QPOs to originate in a torus region spanned by geodesics. The application of the GRPM will also be shown for Xray QPOs seen in Seyferts galaxies. Toward the end, I will discuss our recent efforts for the first official data release of the Indian Pulsar Timing Array (InPTA), which will be incorporated into the global effort of the International Pulsar Timing Array (IPTA) consortium to discover nanoHz gravitational waves emitted by the relativistic supermassive black hole binaries. 
Ansprechpartner: 
Thema: 
Ein Vergleich von kleinen klassischen und quantenmechanischen Spinsystemen 
Datum: 
01.12.22 
Uhrzeit: 
14:15 
Ort: 
D5153 
Vortragender: 
Jonas Steffan 
Universität Bielefeld 

Inhalt: 

Ansprechpartner: 
Thema: 
Stringlocalized quantum fields and some phenomenological applications 
Datum: 
01.12.22 
Uhrzeit: 
16:00 
Ort: 
D5153 
Vortragender: 

University of Zaragoza, Spain 

Inhalt: 
Over fifteen years ago, on the basis of modular theory, stringlocalized quantum fields (SLQF) were developed by Mund, Rehren, Schroer and Yngvason. There were precedents for them, particularly in work by Buchholz and Fredenhagen towards the end of last century. On the theoretical side, SLQFallow to deal with Wigner particles not covered by Wightman's axioms. They provide as well for new viewpoints and techniques in the phenomenology of the Standard Model. 
Ansprechpartner: 
Thema: 
Harmonically confined Riesz gas in one dimension 
Datum: 
30.11.22 
Uhrzeit: 
09:00 
Ort: 
ZOOM / Konferenzschaltung 
Vortragender: 

LPTMS, Universite de ParisSud 

Inhalt: 
I will discuss one dimensional Riesz gas of $N$ particles confined in a harmonic potential. The interaction between any pair of particles at positions x_i and x_j is repulsive and behaves as \sgn(k) x_ix_j^{k} for $i\ne j$, where k>2. For k=1, this model represents the one dimensional one component plasma, for k\to 0^, it represents Dyson's loggas that appears in random matrix theory and for k=2, it represents the classical CalogeroMoser model. We will first compute the average density in the large N limit explicitly for all k>2. Next, we will compute the exact average density (large N limit) in the presence of a hard wall at x=w. Finally, I will discuss the statistics of the position of the rightmost particle in the gas, and will compute the explicit large deviation functions of its distribution. We will see that the left tail exhibits a third order phase transition for all k>2. 
Ansprechpartner: 