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1. Modular apparatus for nuclear reactions spectroscopy (MARS): characterization and first application to determine $$^{12}$$C($$^6$$Li,$$^4$$He)$$^{14}\hbox {N}^{g.s}$$ nuclear reaction cross sections

   https://doi.org/10.1140/epjp/s13360-025-06305-0  

   Garrido-Gómez, L; Vegas-Díaz, A; Alvarez, M_A G; Fernández-García, J P; Fernández, B; Ferrer, F J; Lopez-Aires, D (May 2025, The European Physical Journal Plus)

   Abstract This work presents MARS (Modular apparatus for nuclear reactions spectroscopy) and its characterization prior to its first application to measure$$^6$$ $_{}^6$Li+$$^{12}$$ $_{}^{12}$C nuclear reactions. Measurements were performed at the 3 MV tandem accelerator of the CNA (National Accelerator Center), in Seville, Spain. The$$^{6}$$ $_{}^6$Li projectiles were accelerated at energies around the$$^6$$ $_{}^6$Li+$$^{12}$$ $_{}^{12}$C Coulomb barrier ($$V^{\text {cm}}_{B}\sim 3.0$$ $V_B^{\text{cm}}\sim 3.0$MeV - center of mass and$$V^{\text {lab}}_{B}\sim 4.5$$ $V_B^{\text{lab}}\sim 4.5$MeV - laboratory frame). Using a$$^{6}\hbox {Li}^{2+}$$ $_{}^6{\text{Li}}^{2+}$beam, we measured at 13 laboratory energies from 4.00 to 7.75 MeV. Thus, we present the excitation function of$$^{12}$$ $_{}^{12}$C($$^6$$ $_{}^6$Li,$$^4$$ $_{}^4$He)$$^{14}\hbox {N}^{g.s.}$$ $_{}^{14}{\text{N}}^{g.s.}$reaction, at 2 backward angles ($$110.0^\circ $$ $110.0^{\circ }$and$$140.0^\circ $$ $140.0^{\circ }$). The projectile dissociation, leading to this reaction, increases with the bombarding energies around the Coulomb barrier. This dissociation is favored at an optimum energy$$E_{b}^{\text {op}}$$ $E_b^{\text{op}}$$$\ge $$ $\ge$$$V_{B}$$ $V_B$+$$|Q_{bu}|$$ $|Q_{\mathrm{bu}}|$, where$$V_{B}$$ $V_B$is the Coulomb barrier of the system, and$$|Q_{bu}|$$ $|Q_{\mathrm{bu}}|$is the module ofQ-value for the$$^6$$ $_{}^6$Li dissociation into$$^4$$ $_{}^4$He+$$^2$$ $_{}^2$H. This result corroborates a systematic analysis of weakly bound projectiles reacting on several targets [1]. 

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2. Proton capture on $$^{90}$$Zr revisited

   https://doi.org/10.1140/epja/s10050-025-01521-9  

   Simon, A; Koros, J; Olivas-Gomez, O; Kelmar, R; Churchman, E; Clark, A M; Harris, C; Henderson, S L; Kelly, S E; Millican, P; et al (March 2025, The European Physical Journal A)

   Abstract The$$^{90}$$ $_{}^{90}$Zr(p,$$\gamma $$ $\gamma$)$$^{91}$$ $_{}^{91}$Nb reaction is one of the important reactions in the$$A\approx 90$$ $A\approx 90$mass region and part of the nucleosynthesis path responsible for production of$$^{92}$$ $_{}^{92}$Mo during the$$\gamma $$ $\gamma$-process. Discrepant data in the literature provide a cross section that varies up to 30% within the Gamow window for the$$^{90}$$ $_{}^{90}$Zr(p,$$\gamma $$ $\gamma$)$$^{91}$$ $_{}^{91}$Nb reaction. Thus, the cross section measurements of$$^{90}$$ $_{}^{90}$Zr(p,$$\gamma $$ $\gamma$)$$^{91}$$ $_{}^{91}$Nb reaction were revisited using the$$\gamma $$ $\gamma$-summing technique. The results are consistent with the lower-value cross sections found in the literature. Based on the new data an updated reaction rate for$$^{90}$$ $_{}^{90}$Zr(p,$$\gamma $$ $\gamma$)$$^{91}$$ $_{}^{91}$Nb is provided that is up to 20% higher than that obtained from thenon-smokercode. 

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3. Lifetimes of negative parity states in $$^{162}$$Dy

   https://doi.org/10.1140/epja/s10050-026-01806-7  

   Aprahamian, A; Lesher, S R; Casarella, C; Lee, K; Crider, B P; Lowe, M; Meier, M M; Peters, E E; Prados-Estévez, F M; Ross, T J; et al (April 2026, The European Physical Journal A)

   Abstract Lifetimes of excited states in$$^{162}$$ $_{}^{162}$Dy were measured using the (n,n’$$\gamma $$ $\gamma$) reaction with the Doppler-Shift Attenuation Method (DSAM) at the University of Kentucky’s Accelerator Laboratory. A total of eighteen level lifetimes were obtained, including eleven negative-parity states, seven of which are new. These measurements significantly expand the experimental database of transition probabilities for negative-parity bands in the well-deformed rare earth region of nuclei. The extracted B(E1) and B(E2) values reveal enhanced interband E1 ($$10^{-3}$$ ${10}^{-3}$or$$10^{-4}$$ ${10}^{-4}$) W.u. and E2 strengths (several W.u.) between negative- and positive parity bands, particularly for the KEquation missing<#comment/>bands decaying to the the K$$^{\pi }=2^+_{\gamma }$$ $_{}^{\pi }=2_{\gamma }^{+}$band, consistent with signatures of octupole-quadrupole coupling. In contrast, the K$$^{\pi }=0^-_1$$ $_{}^{\pi }=0_1^{-}$and K$$^{\pi }=1^-_3$$ $_{}^{\pi }=1_3^{-}$bands, which exhibit strong E1 transitions to the ground state band, are indicative of octupole-vibrational excitations built on the deformed ground state. Comparison of transition rates with Alaga rules supports this interpretation and distinguishes collective excitations from likely quasi-particle states. These new results establish$$^{162}$$ $_{}^{162}$Dy as the most extensively characterized rare-earth nucleus for negative parity lifetimes and provide critical experimental benchmarks for theoretical models. 

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4. The $$^{12}$$C$$(\alpha ,\gamma )^{16}$$O reaction, in the laboratory and in the stars

   https://doi.org/10.1140/epja/s10050-025-01537-1  

   de_Boer, R J; Best, A; Brune, C R; Chieffi, A; Hebborn, C; Imbriani, G; Liu, W P; Shen, Y P; Timmes, F X; Wiescher, M (April 2025, The European Physical Journal A)

   Abstract The evolutionary path of massive stars begins at helium burning. Energy production for this phase of stellar evolution is dominated by the reaction path 3$$\alpha \rightarrow ^{12}$$ $\alpha {\to }^{12}$C$$(\alpha ,\gamma )^{16}$$ ${(\alpha ,\gamma )}^{16}$O and also determines the ratio of$$^{12}$$ $_{}^{12}$C/$$^{16}$$ $_{}^{16}$O in the stellar core. This ratio then sets the evolutionary trajectory as the star evolves towards a white dwarf, neutron star or black hole. Although the reaction rate of the 3$$\alpha $$ $\alpha$process is relatively well known, since it proceeds mainly through a single narrow resonance in$$^{12}$$ $_{}^{12}$C, that of the$$^{12}$$ $_{}^{12}$C$$(\alpha ,\gamma )^{16}$$ ${(\alpha ,\gamma )}^{16}$O reaction remains uncertain since it is the result of a more difficult to pin down, slowly-varying, portion of the cross section over a strong interference region between the high-energy tails of subthreshold resonances, the low-energy tails of higher-energy broad resonances and direct capture. Experimental measurements of this cross section require herculean efforts, since even at higher energies the cross section remains small and large background sources are often present that require the use of very sensitive experimental methods. Since the$$^{12}$$ $_{}^{12}$C$$(\alpha ,\gamma )^{16}$$ ${(\alpha ,\gamma )}^{16}$O reaction has such a strong influence on many different stellar objects, it is also interesting to try to back calculate the required rate needed to match astrophysical observations. This has become increasingly tempting, as the accuracy and precision of observational data has been steadily improving. Yet, the pitfall to this approach lies in the intermediary steps of modeling, where other uncertainties needed to model a star’s internal behavior remain highly uncertain. 

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5. CUPID, the Cuore upgrade with particle identification

   https://doi.org/10.1140/epjc/s10052-025-14352-1  

   Alfonso, K; Armatol, A; Augier, C; Avignone_III, F T; Azzolini, O; Barabash, A S; Bari, G; Barresi, A; Baudin, D; Bellini, F; et al (July 2025, The European Physical Journal C)

   Abstract CUPID, the CUORE Upgrade with Particle Identification, is a next-generation experiment to search for neutrinoless double beta decay ($$0\mathrm {\nu \beta \beta }$$ $0\nu \beta \beta$) and other rare events using enriched Li$$_{2}$$ $_2^{}$$$^{100}$$ $_{}^{100}$MoO$$_{4}$$ $_4^{}$scintillating bolometers. It will be hosted by the CUORE cryostat located at the Laboratori Nazionali del Gran Sasso in Italy. The main physics goal of CUPID is to search for$$0\mathrm {\nu \beta \beta }$$ $0\nu \beta \beta$of$$^{100}$$ $_{}^{100}$Mo with a discovery sensitivity covering the full neutrino mass regime in the inverted ordering scenario, as well as the portion of the normal ordering regime with lightest neutrino mass larger than 10 meV. With a conservative background index of 10$$^{-4}$$ $_{}^{-4}$ cts$$/($$ $/($keV$$\cdot $$ $·$kg$$\cdot $$ $·$yr$$)$$ $)$, 240 kg isotope mass, 5 keV FWHM energy resolution at 3 MeV and 10 live-years of data taking, CUPID will have a 90% C.L. half-life exclusion sensitivity of$$1.8\cdot 10^{27}$$ $1.8·{10}^{27}$ yr, corresponding to an effective Majorana neutrino mass ($$m_{\beta \beta }$$ $m_{\beta \beta }$) sensitivity of 9–15 meV, and a$$3\sigma $$ $3\sigma$discovery sensitivity of$$1\cdot 10^{27}$$ $1·{10}^{27}$ yr, corresponding to an$$m_{\beta \beta }$$ $m_{\beta \beta }$range of 12–21 meV. 

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