Newsletter May 2025

Wednesday 28 May 2025, 11:00 → 13:00 Europe/Rome

This is May’s edition of the newsletter of the COST action. The aim is to keep you updated on recent and upcoming conferences and postdoc positions on subjects related to WISPs.

 

Cosmic Wispers preprints

A Fresh Look at the Diffuse ALP Background from Supernova 

Francisco R. Candón, Sougata Ganguly, Maurizio Giannotti, Tanmoy Kumar, Alessandro Lella, Federico Mescia

https://arxiv.org/pdf/2505.05567

Proto-neutron stars, highly compact objects formed in the core of exploding supernovae (SNe), are powerful sources of axion-like particles (ALPs). In the SN core, ALPs are dominantly produced via nucleon-nucleon bremsstrahlung and pion conversion, resulting in an energetic ALP spectrum peaked at energies O(100)MeV. In this work, we revisit the diffuse ALP background, produced from all past core-collapse supernovae, and update the constraints derived from Fermi-LAT observations. Assuming the maximum ALP-nucleon coupling allowed by the SN 1987A cooling, we set the upper limit gaγγ≲2×10^−13 GeV−1 for ALP masses ma≲10^−10 eV, which is approximately a factor of two improvement with respect to the existing bounds. On the other hand, for  ma≳10−10 eV ma​≳10^−10 eV, we find that including pion conversion strengthens the bound on gaγγ, approximately by a factor of two compared to the constraint obtained from bremsstrahlung alone. Additionally, we present a sensitivity study for future experiments such as AMEGO-X, e-ASTROGAM, GRAMS-balloon, GRAMS-satellite, and MAST. We find that the expected constraint from MAST would be comparable to Fermi-LAT bound. However, SN 1987A constraint remains one order of magnitude stronger as compared to the bound derived from the current and future gamma-ray telescopes.

 

We encourage participants in the COST action to send us a small summary, typically smaller than the abstract, of their own articles that will appear in the arXiv (after they appear, with their arXiv numbers). The summary will be disseminated in the newsletter.

Send email to 

Alessandro Lella alessandro.lella@ba.infn.it

Damiano Fiorillo damianofg@gmail.com

with subject: preprint summary for Cosmic WISPers newsletter.

 

 

PhD/Postdoc/Junior Positions

• May

  • Expression of interest for a Marie Skłodowska-Curie fellowship in Particle Cosmology, UCM Madrid link

• June

  • Postdoctoral position in astrophysics and quantum technology, Zaragoza link

 

 

 

Conferences

• June

• Dark Matter 2025: From the Smallest to the Largest Scales (DM2025) link

• UK-Astroparticle Physics Phenomenology: Spring 2025 (UK-APP) link

• Valencia Workshop on the Small-Scale Structure of the Universe and Self-Interacting Dark Matter link

• Making Neutron Stars a Laboratory for New Physics link

• Dark tools link

• Axions in Stockholm link

• July

• Les Houches Summer School 2025: The Dark Universe link

• Dark Side of the Universe 2025 (DSU-2025) link

• International Symposium on Cosmology and Particle Astrophysics: CosPA 2025 (CosPA 2025) link

• International Conference "Dark Matter and Stars: Multi-Messenger Probes of Dark Matter and Modified Gravity" (ICDMS2025)  link

• 11th Summer School in Particle and Astroparticle Physics (GRASPA2025) link

• 30th International Symposium on Particles, Strings and Cosmology (PASCOS 2025) link

• Windows into New Physics in the Sky link

• August

• New Ways to Discover Light New Physics link

• Dark Matter and Neutrino Focus Week link

• TAUP 2025 link

• September

• Invisibles25 Workshop link

• 3rd General Meeting of the COST Action: Cosmic WISPers (CA21106) link

• 3rd Training School of the COST Action: Cosmic WISPers (CA21106) link

• Light Dark World 2025 (LDW 2025) link

• 20th Patras Workshop on Axions WIMPs and WISPs link

• 1st UNDARK workshop: Astrophysical searches of dark sectors with radio wave observations link

• October 

• 28th International Conference on Particle Physics & Cosmology (COSMO 2025) link

• December

• Strings & Cosmology Meeting link