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1. Search for dark matter from the center of the Earth with 10 years of IceCube data

   https://doi.org/10.1140/epjc/s10052-025-14144-7  

   Abbasi, R; Ackermann, M; Adams, J; Agarwalla, S K; Aguilar, J A; Ahlers, M; Alameddine, J M; Amin, N M; Andeen, K; Argüelles, C; et al (May 2025, The European Physical Journal C)

   Abstract The nature of dark matter remains unresolved in fundamental physics. Weakly Interacting Massive Particles (WIMPs), which could explain the nature of dark matter, can be captured by celestial bodies like the Sun or Earth, leading to enhanced self-annihilation into Standard Model particles including neutrinos detectable by neutrino telescopes such as the IceCube Neutrino Observatory. This article presents a search for muon neutrinos from the center of the Earth performed with 10 years of IceCube data using a track-like event selection. We considered a number of WIMP annihilation channels ($$\chi \chi \rightarrow \tau ^+\tau ^-$$ $\chi \chi \to {\tau }^{+}{\tau }^{-}$/$$W^+W^-$$ $W^{+}{W}^{-}$/$$b\bar{b}$$ $b\overline{b}$) and masses ranging from 10 GeV to 10 TeV. No significant excess over background due to a dark matter signal was found while the most significant result corresponds to the annihilation channel$$\chi \chi \rightarrow b\bar{b}$$ $\chi \chi \to b\overline{b}$for the mass$$m_{\chi }=250$$ $m_{\chi }=250$ GeV with a post-trial significance of$$1.06\sigma $$ $1.06\sigma$. Our results are competitive with previous such searches and direct detection experiments. Our upper limits on the spin-independent WIMP scattering are world-leading among neutrino telescopes for WIMP masses$$m_{\chi }>100$$ $m_{\chi }>100$ GeV. 

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2. The neutron veto of the XENONnT experiment: results with demineralized water

   https://doi.org/10.1140/epjc/s10052-025-14105-0  

   Aprile, E; Aalbers, J; Abe, K; Ahmed_Maouloud, S; Althueser, L; Andrieu, B; Angelino, E; Antón_Martin, D; Arneodo, F; Baudis, L; et al (June 2025, The European Physical Journal C)

   Abstract Radiogenic neutrons emitted by detector materials are one of the most challenging backgrounds for the direct search of dark matter in the form of weakly interacting massive particles (WIMPs). To mitigate this background, the XENONnT experiment is equipped with a novel gadolinium-doped water Cherenkov detector, which encloses the xenon dual-phase time projection chamber (TPC). The neutron veto (NV) can tag neutrons via their capture on gadolinium or hydrogen, which release$$\gamma $$ $\gamma$-rays that are subsequently detected as Cherenkov light. In this work, we present the first results of the XENONnT NV when operated with demineralized water only, before the insertion of gadolinium. Its efficiency for detecting neutrons is$$({82\pm 1}){\%}$$ $\left(82\pm 1\right)\%$, the highest neutron detection efficiency achieved in a water Cherenkov detector. This enables a high efficiency of$$({53\pm 3}){\%}$$ $\left(53\pm 3\right)\%$for the tagging of WIMP-like neutron signals, inside a tagging time window of$${250}~{\upmu }\hbox {s}$$ $250\mu \text{s}$between TPC and NV, leading to a livetime loss of$${1.6}{\%}$$ $1.6\%$during the first science run of XENONnT. 

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3. Sensitivity to low-mass WIMPs with an improved liquid argon ionization response model within the DarkSide program

   https://doi.org/10.1103/x3vt-q676  

   Acerbi, F; Adhikari, P; Agnes, P; Ahmad, I; Albergo, S; Albuquerque, I F; Alexander, T; Alton, A K; Amaudruz, P; Angiolilli, M; et al (June 2026, Physical Review D)

   Dark matter detection experiments using liquid argon rely on a precise characterization of the ionization response to nuclear recoils, especially in the keV energy range relevant for light dark matter interactions. In this work, we present a comprehensive analysis that combines new measurements from the ReD setup, part of the DarkSide experimental program, with calibration data from DarkSide-50, as well as results from the ARIS and SCENE experiments. These combined datasets enable improved constraints on atomic screening effects in the modeling of the ionization response of liquid argon to nuclear recoils. The analysis is performed within the Thomas-Imel recombination framework adopted in previous DarkSide studies, and is here further constrained by the inclusion of ReD data, which allow the screening function to be determined from calibration measurements. By including the updated ionization model into the DarkSide-50 analysis framework, we obtain stronger exclusion limits on low-mass weakly interacting massive particle (WIMP) interactions, setting new world-leading constraints in the $1–3\mathrm{GeV}/{\mathrm{c}}^2$WIMP mass range. Finally, we recast the sensitivity projections for the upcoming DarkSide-20k detector, demonstrating a significantly enhanced discovery potential for low-mass dark matter candidates. 

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4. Quality assurance and quality control of the $$26~\text {m}^2$$ SiPM production for the DarkSide-20k dark matter experiment

   https://doi.org/10.1140/epjc/s10052-025-14196-9  

   Acerbi, F; Adhikari, P; Agnes, P; Ahmad, I; Albergo, S; Albuquerque, I F; Alexander, T; Alton, A K; Amaudruz, P; Angiolilli, M; et al (May 2025, The European Physical Journal C)

   Abstract DarkSide-20k is a novel liquid argon dark matter detector currently under construction at the Laboratori Nazionali del Gran Sasso (LNGS) of the Istituto Nazionale di Fisica Nucleare (INFN) that will push the sensitivity for Weakly Interacting Massive Particle (WIMP) detection into the neutrino fog. The core of the apparatus is a dual-phase Time Projection Chamber (TPC), filled with 50 tonnes of low radioactivity underground argon (UAr) acting as the WIMP target. NUV-HD-cryo Silicon Photomultipliers (SiPM)s designed by Fondazione Bruno Kessler (FBK) (Trento, Italy) were selected as the photon sensors covering two$$10.5~\text {m}^2$$ $10.5{\text{m}}^2$Optical Planes, one at each end of the TPC, and a total of$$5~\text {m}^2$$ $5{\text{m}}^2$photosensitive surface for the liquid argon veto detectors. This paper describes the Quality Assurance and Quality Control (QA/QC) plan and procedures accompanying the production of FBK NUV-HD-cryo SiPM wafers manufactured by LFoundry s.r.l. (Avezzano, AQ, Italy). SiPM characteristics are measured at 77 K at the wafer level with a custom-designed probe station. As of March 2025, 1314 of the 1400 production wafers (94% of the total) for DarkSide-20k were tested. The wafer yield is$$93.2\pm 2.5$$ $93.2\pm 2.5$%, which exceeds the 80% specification defined in the original DarkSide-20k production plan. 

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5. Measurement of isolated prompt photon production in pp and p–Pb collisions at the LHC

   https://doi.org/10.1140/epjc/s10052-025-14802-w  

   Acharya, S; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; et al (December 2025, The European Physical Journal C)

   Abstract This paper presents the measurement of the isolated prompt photon inclusive production cross section in pp and p–Pb collisions by the ALICE Collaboration at the LHC. The measurement is performed in p–Pb collisions at centre-of-mass energies per nucleon pair of$$\sqrt{s_{\text {NN}}}={5.02}\,\textrm{TeV}$$ $\sqrt{s_{\text{NN}}}=5.02\text{TeV}$and 8.16 TeV, as well as in pp collisions at$$\sqrt{s}={5.02}\,\textrm{TeV}$$ $\sqrt{s}=5.02\text{TeV}$and 8 TeV. The cross section is obtained at midrapidity$$(|y|<0.7)$$ $\left(\right|y|<0.7)$using a charged-track based isolation momentum$$p_\textrm{T}^{\text {iso,~ch}}<{1.5}\,\textrm{GeV}/c$$ $p_{\text{T}}^{\text{iso, ch}}<1.5\text{GeV}/c$in a cone with radius$$R=0.4$$ $R=0.4$. The data for both collision systems are well reproduced by perturbative QCD (pQCD) calculations at next-to-leading order (NLO) using recent parton distribution functions for free (PDF) and bound (nPDF) nucleons. Furthermore, the nuclear modification factor$$R_{\text {pA}}$$ $R_{\text{pA}}$for both collision energies is consistent with unity for$$p_{\textrm{T}}$$ $p_{\text{T}}$$$>{20}\,\textrm{GeV}/c$$ $>20\text{GeV}/c$. However, deviations from unity ($$R_\textrm{pA}<1$$ $R_{\text{pA}}<1$) of up to 20% are observed for$$p_{\textrm{T}}$$ $p_{\text{T}}$$$<{20}\,\textrm{GeV}/c$$ $<20\text{GeV}/c$with limited significance, indicating the possible presence of nuclear effects in the initial state of the collision. The suppression increases with decreasing$$p_{\textrm{T}}$$ $p_{\text{T}}$with a significance of$$2.3\upsigma $$ $2.3\sigma$for a non-zero slope and yields$$R_{\textrm{pA}}<1$$ $R_{\text{pA}}<1$with a significance of$$1.8\upsigma $$ $1.8\sigma$at$$\sqrt{s_{\textrm{NN}}}={8.16}\,\textrm{TeV}$$ $\sqrt{s_{\text{NN}}}=8.16\text{TeV}$for$$p_{\textrm{T}}$$ $p_{\text{T}}$$$<{20}\,\textrm{GeV}/c$$ $<20\text{GeV}/c$. In addition, a significance of$$1.1\upsigma $$ $1.1\sigma$is observed for$$R_{\textrm{pA}}<1$$ $R_{\text{pA}}<1$at the lower collision energy$$\sqrt{s_{\textrm{NN}}}={5.02}\,\textrm{TeV}$$ $\sqrt{s_{\text{NN}}}=5.02\text{TeV}$for$$p_{\textrm{T}} < {14}\,\textrm{GeV}/c$$ $p_{\text{T}}<14\text{GeV}/c$. The magnitude and shape of the suppression are consistent with pQCD predictions at NLO using nPDFs that incorporate nuclear shadowing effects in the Pb nucleus. 

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