• Tuesday 14 May 2024 at 10:15 in A315 and using Zoom: Tyler Gorda (Frankfurt)
    Probing the behavior of strongly interacting matter at the highest densities
    The cores of the most massive neutron stars contain the densest matter in the universe. What is possible to learn about the behavior of matter near these densities? In this talk, I will discuss two recent papers that study this question. In the first half, I focus on the interplay between information from perturbative QCD calculations and astrophysical data and how these jointly constrain the behavior of matter in the vicinity of the maximum neutron-star density. In the second half, I turn to the post-merger phase of a binary neutron-star merger and highlight a new way to pinpoint the maximum pressure and densities probed in nature.
  • Thursday 23 May 2024 at 14:15 in E204: Hannu Kurki-Suonio (Helsinki)
    Farewell lecture; Hannu retires on 1 July 2024
  • Tuesday 21 May 2024 at 10:15 in A315 and using Zoom: David Milstead (Stockholm)
    Search for baryon number violation and other phenomena with the HIBEAM experiment at the European Spallation Source
    Abstract: The violation of baryon number is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron–antineutron oscillation via mixing, neutron–antineutron oscillation via regeneration from a sterile neutron state and neutron disappearance; the effective process of neutron regeneration is also possible. The program can be used to discover and characterize mixing in the neutron, antineutron and sterile neutron sectors. Furthermore, the intense neutron beam can be used to search for phenomena beyond neutron mixing, such as axions. The experiment addresses topical open questions such as the origin of baryogenesis and the nature of dark matter, and is sensitive to scales of new physics substantially in excess of those available at colliders. A key goal of the program is to open a discovery window to neutron conversion probabilities (sensitivities) by up to three orders of magnitude compared with previous searches. The opportunity to make such a leap in sensitivity tests should not be squandered. The experiment pulls together a diverse international team of physicists from the particle (collider and low energy) and nuclear physics communities, while also including specialists in neutronics and magnetics. A conceptual design report, funded by European Union, for the NNBAR stage has been published. A similar paper for the HIBEAM stage will be complete in 2024.
  • Tuesday 28 May 2024 at 10:15 in A315 and using Zoom: Carlos Hoyos (Oviedo)
    Abstract: TBA

Hopefully the up to 50 min + 10 min discussion long seminar/colloquium will be understandable to a wide audience.
Contacts: Keijo Kajantie (keijo kajantie at helsinki fi) [ HIP seminar],
Jaakko Annala (jaakko annala at helsinki fi) [cosmo seminar]

New Nordic series of seminars over the web, link:
For more information, and to subscribe to email announcements, contact Oscar Henriksson (oscar henriksson at helsinki fi)

Other related seminars

Friday 10-12 seminar series in D114:Astrophysics seminar
Mathematical Physics Seminar and Workshop series Wed 14-16 in Exactum C123.
InstituteQ Events and Seminars