|
Calendar of Physics Talks Vienna
| Alternative scenarios for dark matter productions in the Early Universe and its consequences |
| Speaker: | Yann Mambrini (University: LPT Orsay) |
| Abstract: | Despite very indirect but clear astrophysical and cosmological evidences of the presence of dark matter in our Universe, its nature is still unknown.
Not only the recent direct detection limits exclude the simplest electroweak extensions of the Standard Model like Higgs portal but even question the WIMP paradigm.
Recently, refined cosmological analysis on the reheating mechanism combined with the freeze-in mechanism showed that EeV dark matter particles can be produced from the thermal bath at very early stages of the reheating.
From GUT constructions to high-scale supergravity, several motivated models enter in this category.
We wil detail in this seminar how the production mechanism appears naturally in several motivated UV extensions of the Standard Model, and how ~EeV signals observed by present and future neutrino detectors could be a signature of such mechanism.
|
| Date: | Mon, 24.02.2020 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Kleiner Seminarraum, Boltzmannngasse 5, 5. Stock |
| Contact: | P. Anastasopoulos |
| Matrix factorization and phase retrieval for deep fluorescence microscopy |
| Speaker: | Jonathan Dong (Ecole Normale Supérieure, Paris) |
| Abstract: | Imaging deep inside biological tissues remains a hard challenge nowadays due to multiple light scattering, but it could enable us to observe the activity of individual neurons in the brain. Leveraging recent algorithmic advances, we show how to use matrix factorization and phase retrieval for fluorescence microscopy, as an example of the fruitful interplay between optics and non-linear optimization. |
| Date: | Tue, 25.02.2020 |
| Time: | 17:30 |
| Duration: | 45 min |
| Location: | Josef-Stefan-HS, Boltzmanngasse 5, 1090 Vienna |
| Contact: | Thomas Juffmann |
|