Saturnalia 2025

16 Dec 2025, 09:00 → 19 Dec 2025, 19:00 Europe/Madrid

Seminario de Física Atómica, Nuclear y Molecular (Facultad de Ciencias)

Jacobo Asorey Barreiro (CAPA & Universidad de Zaragoza), Javier Redondo (CAPA, DPTUZ), Laura Segui Iglesia (CAPA, Universidad de Zaragoza), Mathieu Kaltschmidt (CAPA, Universidad de Zaragoza), Siannah Penaranda-Rivas (University of Zaragoza, Spain), Sophia Hollick (CAPA, Universidad de Zaragoza)

Conference series dedicated to catch up with the recent Theoretical and Experimental developments in the broad range of fields covered by our center CAPA, as well as with the adventures and misfortunes of our dear young expats.

Saturnalia2025_Poster.pdf

Tuesday 16 December

11:30 → 12:00 Stripped-Envelope Supernovae for QCD Axion Detection

The QCD axion, arising from the Peccei–Quinn solution to the strong-CP problem, remains one of the most compelling candidates for physics beyond the Standard Model and for the dark matter of the Universe. Core-collapse galactic supernovae provide exceptional laboratories for probing such particles, as the extreme densities and temperatures inside the proto-neutron star lead to copious axion emission. The only “close” supernova observed in modern times, SN 1987A, occurred not in the Milky Way but in the Large Magellanic Cloud at 51 kpc. Despite the limited sensitivity of the only γ-ray telescope operating back then, Solar Maximum Mission (SMM), constraints on axions and axion-like particles ALPs derived from that event are still among the most competitive.

Today, γ-ray telescopes such as Fermi-LAT offer nearly two orders of magnitude greater effective area, making the next Galactic supernova a realistic discovery opportunity. Axions produced during the cooling phase can convert into ~100 MeV photons in the progenitor star’s own magnetic field. In this talk, I will show that stripped-envelope Type Ibc supernovae, which are compact and possess strong surface magnetic fields, provide the optimal conditions for a possible QCD axion detection.

Speaker: Francisco Rodríguez Candón (Universidad de Zaragoza)

WISP_TypeIc.pdf

12:00 → 12:30 Detecting axion dark matter with resonant cavities: The RADES Collaboration

Speaker: Cristian Cogollos Triviño

Saturnalia_2025.pdf

12:30 → 13:00 Multiple ALPs in Laboratory Experiments

Speaker: Sebastian Monath (University of Heidelberg)

SlidesSaragossaSMonath.pdf

Wednesday 17 December

11:30 → 12:00 ANAIS-112: Eight Years Searching for Dark Matter Annual Modulation at LSC

Speaker: Iván Coarasa Casas (CAPA, Universidad de Zaragoza)

Saturnalia2025_ANAIS_IvanCoarasa.pdf

12:00 → 12:30 Casimir Energy in Non-Abelian Gauge Theories

Speaker: Fernando Ezquerro (CAPA, Universidad de Zaragoza)

Casimir_gauge.pdf

12:30 → 13:00 Prospects of CMB B-modes with future CMB and large-scale structure experiments

In the era of high precision Cosmic Microwave Background (CMB) anisotropy measurements, detection of primordial B-modes polarisation will be one of the goals of the current and upcoming CMB experiments. In this talk I will present the methodology of detecting B-modes from Simons Observatory-like CMB experiment. I will also discuss how including probes of large scale structure can improve the measurement of tensor-to-scalar ratio.

Speaker: Chandra Shekhar Saraf (Korea Astronomy and Space Science Institute)

ChandraShekhar_Saraf.pdf

Thursday 18 December

12:30 → 13:00 GeV-ALP searches with ALP-aca

Axion-Like particles (ALPs) are pseudoscalar neutral particles that are predicted by many New Physics theories. The GeV mass range is interesting for several reasons: the constraints in parameter space are weaker, the flavour structure of the couplings to SM fermions plays an important role, and it can be explored by different experiments such as BESIII, Belle II and LHCb. But there is also an important theoretical challenge in the description of ALP processes involving light mesons. In this talk, I will present the code ALP-aca (ALP automatic computing algorithm) that we have developed in order to study the phenomenology of GeV ALPs, and discuss some application in ALPs produced in flavour-changing meson decays, quarkonia decays and proton collisions.

Speaker: Jorge Alda (Università degli Studi di Padova)

alpaca_saturnalia25.pdf

13:00 → 13:30 Axion searches with IAXO: from the Sun to Supernovae

Speaker: María Jiménez Puyuelo (Universidad de Zaragoza / CAPA)

IAXO_Saturnalia2025_MJP.pdf

13:30 → 14:00 Taming forward-scattering singularities in partial waves: Is the classical Higgs unitarity bound well defined?

Speaker: Pablo Quílez Lasanta (CERN)

P.Quilez-Saturnalia 2025.pdf

Friday 19 December

12:30 → 13:00 Scientific Data Management at CERN

Speaker: Luis Antonio Obis Aparicio (University of Zaragoza)

Luis Saturnalia 2025.pdf

13:00 → 13:30 Characterization of 39Ar Activity for DarkSide-20k with DArTinArDM

Speaker: Swadheen Bharat (CAPA, Universidad de Zaragoza)

Saturnalia_2025_Swadheen.pdf

13:30 → 14:00 Many-body wavefunctions from conformal field theory

In quantum many-body physics, ansatz wavefunctions and toy models can provide useful information about entanglement patterns and phases of matter. In this talk, we introduce families of spin chain wavefunctions defined in terms of correlators in chiral conformal field theory, which interpolate between well-known gapped and gapless exactly solvable models, and give rise to a certain correspondence between the geometry of the quantum field theory and the entanglement content of the spin chain.

Speaker: Adrián Franco Rubio (U. Complutense de Madrid)

Saturnalia.pdf