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1. Reduction of spectroscopic overlap across the $Z=8$ shell in neutron-rich nuclei

   https://doi.org/10.1103/PhysRevC.109.054325  

   Redpath, T; Guèye, P; Baumann, T; Brown, B A; Cunningham, A; DeYoung, P A; Frank, N; Hoffman, C R; Kuchera, A N; Godoy, B Monteagudo; et al (May 2024, Physical Review C)

   Zhang, Lin (Ed.)

   The recent discovery and spectroscopic measurements of ${}^{27}\mathrm{O}$and ${}^{28}\mathrm{O}$suggests the disappearance of the $N=20$shell structure in these neutron-rich oxygen isotopes. We measured one- and two-proton removal cross sections from ${}^{27}\mathrm{F}$and ${}^{29}\mathrm{Ne}$, respectively, extracting spectroscopic factors and comparing them to shell model overlap functions coupled with eikonal reaction model calculations. The invariant mass technique was used to reconstruct the two-body ( ${}^{24}\mathrm{O}+n$) and three-body ( ${}^{24}\mathrm{O}+2n$) decay energies from knockout reactions of ${}^{27}\mathrm{F}$(106.2 MeV/u) and ${}^{29}\mathrm{Ne}$(112.8 MeV/u) beams impinging on a ${}^9\mathrm{Be}$target. The one-proton removal from ${}^{27}\mathrm{F}$strongly populated the ground state of ${}^{26}\mathrm{O}$and the extracted cross section of $3.4_{-1.5}^{+0.3}$mb agrees with eikonal model calculations that are normalized by the shell model spectroscopic factors and account for the systematic reduction factor observed for single nucleon removal reactions within the models used. For the two-proton removal reaction from ${}^{29}\mathrm{Ne}$an upper limit of 0.08 mb was extracted for populating states in ${}^{27}\mathrm{O}$decaying though the ground state of ${}^{26}\mathrm{O}$. The measured upper limit for the population of the ground state of ${}^{26}\mathrm{O}$in the two-proton removal reaction from ${}^{29}\mathrm{Ne}$indicates a significant difference in the underlying nuclear structure of ${}^{27}\mathrm{F}$and ${}^{29}\mathrm{Ne}$. Published by the American Physical Society2024 

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2. Asymptotic normalization coefficients for $\alpha +{}^{12}\mathrm{C}$ synthesis and the $S$ factor for ${}^{12}\mathrm{C}(\alpha ,\gamma ){}^{16}\mathrm{O}$ radiative capture

   https://doi.org/10.1103/PhysRevC.110.055803  

   Mukhamedzhanov, A M; deBoer, R J; Irgaziev, B F; Blokhintsev, L D; Kadyrov, A S; Savin, D A (November 2024, Physical Review C)

   : The ${}^{12}\mathrm{C}(\alpha ,\gamma ){}^{16}\mathrm{O}$reaction, determining the survival of carbon in red giants, is of interest for nuclear reaction theory and nuclear astrophysics. A specific feature of the ${}^{16}\mathrm{O}$nuclear structure is the presence of two subthreshold bound states, (6.92 MeV, $2^{+}$) and (7.12 MeV, $1^{-}$), that dominate the behavior of the low-energy $S$factor. The strength of these subthreshold states is determined by their asymptotic normalization coefficients (ANCs), which need to be known with high accuracy. : The objective of this research is to examine how the subthreshold and ground-state ANCs impact the low-energy $S$factor, especially at the key astrophysical energy of $300\mathrm{keV}$. The $S$factors are calculated within the framework of the $R$-matrix method using the code. Our total $S$factor takes into account the $E1$and $E2$transitions to the ground state of ${}^{16}\mathrm{O}$including the interference of the subthreshold and higher resonances, which also interfere with the corresponding direct captures, and cascade radiative captures to the ground state of ${}^{16}\mathrm{O}$through four subthreshold states: $0_2^{+},3^{-},2^{+}$, and $1^{-}$. To evaluate the impact of subthreshold ANCs on the low-energy $S$factor, we employ two sets of the ANCs. The first selection, which offers higher ANC values, is attained through the extrapolation process [Blokhintsev , ]. The set with low ANC values was employed by deBoer []. A detailed comparison of the $S$factors at the most effective astrophysical energy of 300 keV is provided, along with an investigation into how the ground-state ANC affects this $S$factor. : The contribution to the total $E1$and $E2S$factors from the corresponding subthreshold resonances at $300\mathrm{keV}$are $(71–74)\%$and $(102–103)\%$, respectively. The correlation of the uncertainties of the subthreshold ANCs with the $E1$and $E2S\left(300\mathrm{keV}\right)$factors is found. The $E1$transition of the subthreshold resonance $1^{-}$does not depend on the ground-state ANC but interferes constructively with a broad $(9.585\mathrm{MeV};1^{-})$resonance giving (for the present subthreshold ANC) an additional $26\%$contribution to the total $E1S\left(300\mathrm{keV}\right)$factor. Interference of the $E2$transition through the subthreshold resonance $2^{+}$with direct capture is almost negligible for small ground-state ANC of $58{\mathrm{fm}}^{-1/2}$. However, its interference with direct capture for higher ground-state ANC of $337{\mathrm{fm}}^{-1/2}$is significant and destructive, contributing $-27\%$. The low-energy $S_{E2}\left(300\mathrm{keV}\right)$factor experiences a smaller increase when both subthfreshold and the ground-state ANCs rise together due to their anticorrelation, compared to when only the subthreshold ANCs increase. Published by the American Physical Society2024 

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3. Strength measurements of the $E_{\mathrm{R}}^{\mathrm{lab}}=647$ and 1842 keV resonances in the ${}^{40}\mathrm{Ca}(p,\gamma ){}^{41}\mathrm{Sc}$ reaction and their relevance in novae nucleosynthesis

   https://doi.org/10.1103/PhysRevC.111.025804  

   Sidhu, R S; deBoer, R J; Görres, J; Wiescher, M; Koros, J; Manukyan, K; Matney, M; McDonaugh, J; Picciotto, V; Sanchez, A T; et al (February 2025, Physical Review C)

   Here we report on the direct measurement of the resonance strengths of the $E_{\mathrm{R}}^{\mathrm{lab}}=647\mathrm{keV}$and 1842 keV resonances in the ${}^{40}\mathrm{Ca}(p,\gamma ){}^{41}\mathrm{Sc}$reaction. At novae temperatures, $0.2<T_9<0.7$, the ${}^{40}\mathrm{Ca}(p,\gamma ){}^{41}\mathrm{Sc}$reaction is governed by the low energy resonance at $E_{\mathrm{R}}^{\mathrm{lab}}=647\mathrm{keV}$, whereas the $E_{\mathrm{R}}^{\mathrm{lab}}=1842\mathrm{keV}$resonance serves as a normalization standard for nuclear reaction experiments within the astrophysically relevant energy range. For the $E_{\mathrm{R}}^{\mathrm{lab}}=647\mathrm{keV}$resonance, we obtain a resonance strength $\omega \gamma =(2.51\pm 0.{09}_{\mathrm{stat}}\pm 0.{22}_{\mathrm{syst}})\mathrm{meV}$, with an uncertainty a factor of 2.5 smaller than the previous direct measurement value. For the $E_{\mathrm{R}}^{\mathrm{lab}}=1842\mathrm{keV}$resonance, we obtain a resonance strength $\omega \gamma =(0.148\pm 0.{006}_{\mathrm{stat}}\pm 0.{013}_{\mathrm{syst}})\mathrm{eV}$, which is consistent with previous studies but deviates by $2\sigma$from the most recent measurement. Our results suggest ${}^{40}\mathrm{Ca}$to be a strong waiting point in the nucleosynthesis path of oxygen-neon (ONe) novae. Published by the American Physical Society2025 

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4. Observation of the Open-Charm Tetraquark Candidate $T_{cs0}^{*}(2870{)}^0$ in the $B^{-}\to D^{-}{D}^0{K}_S^0$ Decay

   https://doi.org/10.1103/PhysRevLett.134.101901  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adefisoye, A A; Adeva, B; Adinolfi, M; Adlarson, P; Agapopoulou, C; et al (March 2025, Physical Review Letters)

   An amplitude analysis of $B^{-}\to D^{-}{D}^0{K}_S^0$decays is performed using proton-proton collision data, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. A resonant structure of spin-parity $0^{+}$is observed in the $D^0{K}_S^0$invariant-mass spectrum with a significance of $5.3\sigma$. The mass and width of the state, modeled with a Breit-Wigner line shape, are determined to be $2883\pm 11\pm 8\mathrm{MeV}/c^2$and ${87}_{-47}^{+22}\pm 17\mathrm{MeV}$, respectively, where the first uncertainties are statistical and the second systematic. These properties and the quark content are consistent with those of the open-charm tetraquark candidate $T_{cs0}^{*}(2870{)}^0$observed previously in the $D^{+}{K}^{-}$final state of the $B^{-}\to D^{-}{D}^{+}{K}^{-}$decay. This result confirms the existence of the $T_{cs0}^{*}(2870{)}^0$state in a new decay mode. The $T_{cs1}^{*}(2900{)}^0$state, reported in the $B^{-}\to D^{-}{D}^{+}{K}^{-}$decay, is also searched for in the $D^0{K}_S^0$invariant-mass spectrum of the $B^{-}\to D^{-}{D}^0{K}_S^0$decay, without finding evidence for it. © 2025 CERN, for the LHCb Collaboration2025CERN 

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5. First measurement of $D_{s1}\left(1^{+}\right)(2536{)}^{+}$ and $D_{s2}^{*}\left(2^{+}\right)(2573{)}^{+}$ production in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$ at the LHC

   https://doi.org/10.1103/PhysRevD.111.112005  

   Acharya, S; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; et al (June 2025, Physical Review D)

   The production yields of the orbitally excited charm-strange mesons ${\mathrm{D}}_{\mathrm{s}1}\left(1^{+}\right)(2536{)}^{+}$and ${\mathrm{D}}_{\mathrm{s}2}^{*}\left(2^{+}\right)(2573{)}^{+}$were measured for the first time in proton-proton (pp) collisions at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$with the ALICE experiment at the LHC. The ${\mathrm{D}}_{\mathrm{s}1}^{+}$and ${\mathrm{D}}_{\mathrm{s}2}^{*+}$mesons were measured at midrapidity ( $\left|y\right|<0.5$) in minimum-bias and high-multiplicity pp collisions in the transverse-momentum interval $2<p_{\mathrm{T}}<24\mathrm{GeV}/c$. Their production yields relative to the ${\mathrm{D}}_{\mathrm{s}}^{+}$ground-state yield were found to be compatible between minimum-bias and high-multiplicity collisions, as well as with previous measurements in ${\mathrm{e}}^{\pm }\mathrm{p}$and ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$collisions. The measured ${\mathrm{D}}_{\mathrm{s}1}^{+}/{\mathrm{D}}_{\mathrm{s}}^{+}$and ${\mathrm{D}}_{\mathrm{s}2}^{*+}/{\mathrm{D}}_{\mathrm{s}}^{+}$yield ratios are described by statistical hadronization models and can be used to tune the parameters governing the production of excited charm-strange hadrons in Monte Carlo generators, such as 8. 

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