Astrophysical seminar - September

Attendees: 

In person (IFJ PAN) - Shreya, Richard, Megha, Andreas Mz, Michael Fucille, Adrian, Chaitanya, and Paweł Lysik

Remote - Sarah, Ayush Fotedar, Bartosz Izydorczyk, Grzegorz, Swathi, Tomasz, and Rameshan Thimappa

Minutes:

General: Slow start with the setup. 

Agenda:

1. Introduce the Forum to new members and participants

1. Welcome Adrian Šaina

2. Presentation by Richard on “Testing Neutrino Mass Models at Colliders”

3. QnA based on the presentation

1. Are these the only combinations of Dirac and Majorana mass components for the Lagrangian to be renormalizable? - No, but these are some of the simple examples shown here

2. Why are there no (non-neutrino) lepton oscillations? And if they were, how different would they be from neutrino oscillations? - It is by design that there are no lepton oscillations; the top and down quarks align with the mass eigenstates. Kinematically, the scales of impact are so large, with respect to the mass, that on astronomical scales, we would see significant differences with the oscillations of leptons. If it did exist, we would notice the differences much earlier.

3. How do we interpret the two flavour eigenstates? - as interaction eigenbases

4. You mentioned that there are at least two non-zero mass neutrinos. Can that be used to restrict some theories? - The oscillation data is described by the 3x3 paradigm, which leads to 2 mass splittings. We just don’t know what ordering of neutrinos the non-zero mass components correspond to.

5. Does the factor of 1/2 in the Majorana Lagrangian show in the interaction formulation? - No, the covariant or functional derivatives take care of the additional factor. But we can note this factor if we observe Lepton Number Violation (Black Box theorem).

6. In cosmology, there is a concept of the conservation of the total neutrino number - It is model dependent.

4. Forum organization

   1. Syed

   2. Swathi

   3. Megha

1. Nominations for the role of Deputy General Coordinator

2. Deadline: October 9th

3. Election: end of October

4. New task group members needed for Task group #3, #4, and #5

5. Request for guests for “Our Future in Research”

1. Event organized under the project “MOST-PAN” - co-financing of international events organized by young scientists. Megha is the co-chair of the event.

2. Tentative dates of the event: October 29-30

3. Need 10 guests (young PostDocs to early-career scientists) affiliated with international institutes to share their post-PhD experiences

4. Agenda: Short self-introductions, 2 panel sessions (one with only women panelists), and Knowledge Cafe

5. Need help with at least 4 more guests

6. Event open to PhD students from all PAN institutes

7. Contact Megha (megha.mogarkar@ifj.edu.pl) for more details

6. AOB:

1. Continuing the spooky theme for October, we will have 2 more meetings this month, based on Dark Matter.

2. We will read the preprint paper from the LUX-ZEPLIN experiment - "Search for dark matter particle interactions in an extended nuclear recoil energy
   window with the LUX-ZEPLIN (LZ) experiment"(https://doi.org/10.48550/arXiv.2609.02823). Adrian will summarize the paper to start the 2nd session of the New Paper, Open Discussion meeting.

3. Adrian will present a seminar on his work on Dark Matter. The title of the seminar is TBD

4. Dates of the two meetings are also TBD