A narrow near-threshold proton-emitting resonance ($E_x=11.4\mathrm{MeV}$, $J^{\pi }=1/2^{+}$, and ${\mathrm{\Gamma }}_p=4.4\mathrm{keV}$) was directly observed in ${}^{11}\mathrm{B}$ via proton resonance scattering. This resonance was previously inferred in the $\beta$-delayed proton emission of the neutron halo nucleus ${}^{11}\mathrm{Be}$. The good agreement between both experimental results serves as a ground to confirm the existence of such exotic decay and the particular behavior of weakly bound nuclei coupled to the continuum. $R$-matrix analysis shows a sizable partial decay width for both, proton and $\alpha$ (${\mathrm{\Gamma }}_{\alpha }=11\mathrm{keV}$) emission channels.

Absolute cross sections for the addition of $s$- and $d$-wave neutrons to ${}^{14}\mathrm{C}$ and ${}^{14}\mathrm{N}$ have been determined simultaneously via the $(d,p)$ reaction at $10\mathrm{MeV}/\mathrm{u}$. The difference between the neutron and proton separation energies, $\mathrm{\Delta }S$, is around $-20\mathrm{MeV}$ for the ${}^{14}\mathrm{C}+n$ system and $+8\mathrm{MeV}$ for ${}^{14}\mathrm{N}+n$. The population of the $1s_{1/2}$ and $0d_{5/2}$ orbitals for both systems is reduced by a factor of approximately 0.5 compared with the independent single-particle model, or about 0.6 when compared with the shell model. This finding strongly contrasts with results deduced from intermediate-energy knockout reactions between similar nuclei on targets of ${}^9\mathrm{Be}$ and ${}^{12}\mathrm{C}$. The simultaneous technique used removes many systematic uncertainties.

Elastic and inelastic alpha scatterings on ${}^{10}\mathrm{C}$ were measured using a 68-MeV/u radioactive ${}^{10}\mathrm{C}$ beam incident on the recently developed MAIKo active target system. The phenomenological effective $\alpha \text{−}N$ interaction and the point-nucleon density distribution in the ground state were determined from the elastic scattering data. The cross sections of the inelastic alpha scattering were calculated using this interaction and density distribution and were compared with the experiment to determine the neutron quadrupole transition matrix element $M_n$ between the ground state and the $2_1^{+}$ state at $E_x=3.35$ MeV in ${}^{10}\mathrm{C}$. The deduced neutron transition matrix element is $M_n=6.9\pm 0.7\left(\mathrm{fit}\right)\pm 1.2\left(\mathrm{sys}\right){\mathrm{fm}}^2$. The ratio of the neutron transition strength to proton transition strength was determined as $M_n/M_p=1.05\pm 0.11\left(\mathrm{fit}\right)\pm 0.17\left(\mathrm{sys}\right)$, which indicates that the quadrupole transition between the ground state and the $2_1^{+}$ state in ${}^{10}\mathrm{C}$ is less neutron dominant compared to that in ${}^{16}\mathrm{C}$.

The ${}^{30}\mathrm{P}(p,\gamma ){}^{31}\mathrm{S}$ reaction plays an important role in understanding the nucleosynthesis of $A\ge 30$ nuclides in oxygen-neon novae. The Gaseous Detector with Germanium Tagging was used to measure ${}^{31}\mathrm{Cl}$ $\beta$-delayed proton decay through the key $J^{\pi }=3/2^{+}$, 260-keV resonance. The intensity $I_{\beta p}^{260}=8.3_{-0.9}^{+1.2}\times {10}^{-6}$ represents the weakest $\beta$-delayed, charged-particle emission ever measured below 400 keV, resulting in a proton branching ratio of ${\mathrm{\Gamma }}_p/\mathrm{\Gamma }=2.5_{-0.3}^{+0.4}\times {10}^{-4}$. By combining this measurement with shell-model calculations for ${\mathrm{\Gamma }}_{\gamma }$ and past work on other resonances, the total ${}^{30}\mathrm{P}(p,\gamma ){}^{31}\mathrm{S}$ rate has been determined with reduced uncertainty. The new rate has been used in hydrodynamic simulations to model the composition of nova ejecta, leading to a concrete prediction of ${}^{30}\mathrm{Si}$:${}^{28}\mathrm{Si}$ excesses in presolar nova grains and the calibration of nuclear thermometers.

The NEXT collaboration is dedicated to the study of double beta decays of $$^{136}$$ 136 Xe using a high-pressure gas electroluminescent time projection chamber. This advanced technology combines exceptional energy resolution ( $$\le 1\%$$ ≤ 1 % FWHM at the $$Q_{\beta \beta }$$ Q β β value of the neutrinoless double beta decay) and powerful topological event discrimination. Building on the achievements of the NEXT-White detector, the NEXT-100 detector started taking data at the Laboratorio Subterráneo de Canfranc (LSC) in May of 2024. Designed to operate with xenon gas at 13.5 bar, NEXT-100 consists of a time projection chamber where the energy and the spatial pattern of the ionising particles in the detector are precisely retrieved using two sensor planes (one with photo-multiplier tubes and the other with silicon photo-multipliers). The detector has been operating at stable conditions using argon and xenon gases at $$\sim $$ ∼ 4 bar and drift fields of $$74\hbox { V cm}^{-1}$$ 74 V cm - 1 and $$118\hbox { V cm}^{-1}$$ 118 V cm - 1 , respectively. Alpha decays from the $$^{222}$$ 222 Rn chain have been used to test and monitor the stability of the detector, showing a constant electron lifetime in the drift volume. In this paper, in addition to reporting the results of the commissioning run, we provide a detailed description of the NEXT-100 detector, describe its assembly, and present the current estimation of the radiopurity budget.

We demonstrate a new technique for obtaining fission data for nuclei away from $\beta$ stability. These types of data are pertinent to the astrophysical $r$ process, crucial to a complete understanding of the origin of the heavy elements, and for developing a predictive model of fission. These data are also important considerations for terrestrial applications related to power generation and safeguarding. Experimentally, such data are scarce due to the difficulties in producing the actinide targets of interest. The solenoidal-spectrometer technique, commonly used to study nucleon-transfer reactions in inverse kinematics, has been applied to the case of transfer-induced fission as a means to deduce the fission-barrier height, among other variables. The fission-barrier height of ${}^{239}\mathrm{U}$ has been determined via the ${}^{238}\mathrm{U}(d,pf)$ reaction in inverse kinematics, the results of which are consistent with existing neutron-induced fission data indicating the validity of the technique.