Zeit, Ort:

11:15 Uhr, Grosser Hoersaal/Big Lecture Hall (library)

Redner:

Livia Ludhova, on behalf of the JUNO Collaboration

Titel:

First Measurement of Reactor Neutrino Oscillations with JUNO

Neutrino oscillations are a fundamental quantum phenomenon demonstrating that neutrinos have non-zero mass and that the Standard Model in its minimal form must be extended. Their precise measurement plays a central role in particle physics and astroparticle physics, providing unique insight into the properties of neutrinos and their role in the Universe.The Jiangmen Underground Neutrino Observatory (JUNO) in China, after more than 15 years from concept to full realization, started taking data in August 2025. With its 20-kiloton liquid scintillator target, JUNO is the first multi-kiloton liquid scintillator detector and has been designed to combine its large size with unprecedented energy resolution. This unique combination enables the observation of the fine oscillation pattern of reactor antineutrinos and opens a new level of precision in neutrino oscillation measurements.In this talk, I will present the first oscillation results obtained during the initial phase of data taking. With only 59 days of data, JUNO has already achieved a world-leading precision measurement of the solar oscillation parameters\sin^2 \theta_{12} and \Delta m^2_{21},demonstrating the excellent performance of the detector.I will discuss the detector, analysis strategy, and physics implications of these results.Finally, I will outline JUNO's broader scientific program, spanning precision measurements of reactor neutrino oscillations and a wide range of topics in astroparticle physics.These results establish the foundation for JUNO's future precision neutrino physics program.

Zeit, Ort:

11:00 Uhr, Central seminar room, library building

Redner:

Philipp Mertsch

Titel:

Galactic cosmic rays as an interstellar laboratory

Cosmic rays are a fundamental component of the Galactic ecosystem and offer insights that reach beyond the Milky Way, including how galaxies form and evolve. They also serve as probes for new physics, such as dark matter and primordial antimatter. However, all such investigations hinge on resolving the century-old question of cosmic-ray origin. Over the last decade and a half, space-based missions like AMS-02, CALET, and DAMPE have delivered a wealth of data; more recently, the ground-based LHAASO has provided high-precision measurements of protons and helium. Modeling these observations enables inferences about the classes of cosmic-ray sources and the conditions that govern their propagation -- for example, transport through turbulent magnetic fields. The emerging picture is quite intricate, suggesting that prevailing models must be revised, if not completely reworked. I will highlight recent advances in modelling Galactic cosmic rays from stochastic source populations and explore the implications for diffuse emission. A specific class of such models are motivated by evidence for inhibited diffusion around Galactic cosmic-ray sources. If time permits, I will also review recent findings on the transport of magnetic field lines and particles in synthetic turbulence.

Zeit, Ort:

09:30 Uhr, Central seminar room, library building

Redner:

Dr. Marta Murillo Sanchez; Ultrafast Liquid Crystal Dynamics

Titel:

High-harmonic spectroscopy in liquid crystals: Tracking the nematic–isotropic phase transition

Zeit, Ort:

11:15 Uhr, Central seminar room, library building

Redner:

Dr. Alex Kavner (University of Zurich)

Titel:

Super Lindhard ionization from sub-keV nuclear recoils: implications for CEvNS and dark matter searches

Germanium is an essential element for the advancement of nuclear and particle physics. High purity germanium detectors are utilized across diverse experiments including: neutrino-less double beta decay, coherent elastic neutrino nuclear scattering (CEvNS), dark matter searches, nuclear decay experiments, and many others. Full understanding of detector response to low energy nuclear recoils is of high importance being primary signature of both CEvNS and dark matter. Several recent measurements have probed the ionization produced by 254 eVnr nuclear recoils and found a significant enhancement over the theoretical prediction. These results will be discussed as well as their relevance for existing CEvNS experiments and the upcoming TESSERACT dark matter experiment.

Zeit, Ort:

15:00 Uhr, Central seminar room, library building

Redner:

Prof. Agapi Emmanouilidou; University College London

Titel:

Delay times and Coulomb explosion imaging in interaction of small molecules with XFEL pulses

Zeit, Ort:

11:15 Uhr, Central seminar room, library building

Redner:

Till Jahnke

Titel:

Molecular Ground-State Fluctuations: Subtle Feature, Large Impact