000162774 001__ 162774 000162774 005__ 20251017144629.0 000162774 0247_ $$2doi$$a10.1103/d194-7t6x 000162774 0248_ $$2sideral$$a145347 000162774 037__ $$aART-2025-145347 000162774 041__ $$aeng 000162774 100__ $$aRodríguez Candón, Francisco$$uUniversidad de Zaragoza 000162774 245__ $$aFresh look at the diffuse ALP background from supernovae 000162774 260__ $$c2025 000162774 5060_ $$aAccess copy available to the general public$$fUnrestricted 000162774 5203_ $$aProtoneutron stars, highly compact objects formed in the core of exploding supernovae (SNe), are powerful sources of axionlike particles (ALPs). In the SN core, ALPs are dominantly produced via nucleon-nucleon bremsstrahlung and pion conversion, resulting in an energetic ALP spectrum peaked at energies O(100) MeV. In this work, we revisit the diffuse ALP background, produced from all past core-collapse supernovae, and update the constraints derived from -LAT observations. Assuming the maximum ALP-nucleon coupling allowed by the SN 1987A cooling, we set the upper limit gaγγ≲2×10−13 GeV−1 for ALP mass ma≲10−10 eV, which is approximately a factor of two improvement with respect to the existing bounds. On the other hand, for ma≳10−10 eV, we find that including pion conversion strengthens the bound on gaγγ, approximately by a factor of two compared to the constraint obtained from bremsstrahlung alone. Additionally, we present a sensitivity study for future experiments such as AMEGO-X, e-ASTROGAM, GRAMS-balloon, GRAMS-satellite, and MAST. We find that the expected constraint from MAST would be comparable to -LAT bound. However, SN 1987A constraint remains one order of magnitude stronger as compared to the bound derived from the current and future gamma-ray telescopes. 000162774 536__ $$9info:eu-repo/grantAgreement/ES/AEI/PID2021-126078NB-C21$$9info:eu-repo/grantAgreement/EUR/COST/CA21106-COSMIC Wispers$$9info:eu-repo/grantAgreement/EC/H2020/788781/EU/Towards the detection of the axion with the International Axion Observatory/IAXOplus$$9This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 788781-IAXOplus$$9info:eu-repo/grantAgreement/ES/MINECO/PID2019-108122GB-C31$$9info:eu-repo/grantAgreement/ES/NextGenerationEU/INVESTIGO-095-28 000162774 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttps://creativecommons.org/licenses/by/4.0/deed.es 000162774 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000162774 700__ $$aGanguly, Sougata 000162774 700__ $$0(orcid)0000-0001-9823-6262$$aGiannotti, Maurizio$$uUniversidad de Zaragoza 000162774 700__ $$aKumar, Tanmoy 000162774 700__ $$aLella, Alessandro 000162774 700__ $$aMescia, Federico 000162774 7102_ $$12004$$2038$$aUniversidad de Zaragoza$$bDpto. Física Teórica$$cÁrea Astronomía y Astrofísica 000162774 7102_ $$12004$$2390$$aUniversidad de Zaragoza$$bDpto. Física Teórica$$cÁrea Física Atóm.Molec.y Nucl. 000162774 773__ $$g112, 1 (2025), 015006 [10 pp.]$$pPhys. rev. D$$tPhysical Review D$$x2470-0010 000162774 8564_ $$s593566$$uhttps://zaguan.unizar.es/record/162774/files/texto_completo.pdf$$yVersión publicada 000162774 8564_ $$s2729135$$uhttps://zaguan.unizar.es/record/162774/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000162774 909CO $$ooai:zaguan.unizar.es:162774$$particulos$$pdriver 000162774 951__ $$a2025-10-17-14:25:21 000162774 980__ $$aARTICLE