The elastic $\alpha$-$^{12}$C scattering at low energies for $l=0,1,2,3,4,5,6$ is studied in effective field theory. We discuss the construction of the $S$ matrices of elastic $\alpha$-$^{12}$C scattering in terms of the amplitudes of sub-threshold bound and resonant states of $^{16}$O, which are calculated from the effective Lagrangian. The parameters appearing in the $S$ matrices are fitted...
Triple-$\alpha$ reaction plays a significant role in nucleosynthesis heavier than $^{12}$C and concomitant stellar evolution [1]. The reaction rates of this reaction at the helium-burning temperatures, $T_9 > 0.1$, are dominated by the sequential process via two narrow resonances: $\alpha+\alpha\rightarrow ^8$Be(0$^+_1$), $^8$Be+$\alpha \rightarrow ^{12}$C(0$^+_2$: $E=0.379$ MeV) [2,3], and...
When stars approach the red giant branch, a deep convective envelope develops and the products of the CNO cycle appear at the stellar surface. In particular, the $\rm ^{17}O$ is enhanced in RGB and AGB stars. Spectroscopic analyses of O isotopic ratios of these stars provide a powerful tool to investigate the efficiency of deep mixing processes, such as those powered by convective overshoot,...
Asymptotic giant branch (AGB) stars are a key site of element synthesis in galaxies. As low-mass AGB stars evolve, they undergo internal helium-burning shell flashes, or thermal pulses. These thermal pulses temporarily extinguish the hydrogen-burning shell, allowing the convective envelope of the star to move into the intershell region, mixing products of helium-burning to the surface,...
The radiative proton capture reaction of $^{15}\mathrm{N}(p, \gamma)^{16}\mathrm{O}$ is one of the thermonuclear reactions in the carbon-nitrogen-oxygen (CNO) cycle. This process provides a link between the type-I (CN) cycle and type-II (NO) cycle so that the $^{16}\mathrm{O}$ nucleus can be produced and the further types of the cycle start. We investigated the $^{15}\mathrm{N}(p,...
The $^{17}\mathrm{O}(p,\gamma)^{18}\mathrm{F}$ reaction plays a crucial role in Hydrogen burning via CNO cycle. In particular at temperatures of interest for HBB in AGB stars ($20\,\mathrm{MK}<\mathrm{T}<80\,\mathrm{MK}$) the main contribution to the astrophysical reaction rate comes from the poorly constrained $E_R = 65\,\mathrm{keV}$ resonance. The strength of this resonance has only been...
In recent years the plethora of new astronomical observations has shown that the synthesis of heavy elements cannot be explained just by the three traditional processes (s, r, and p). For this reason, new processes have been proposed that are able to explain these new observations. The ``intermediate'' or i process (see e.g. [1]) is one such process and corresponds to neutron densities and...
Nucleosynthesis of heavy elements has been traditionally attributed to two neutron-capture processes, namely the s and r processes. Recent astronomical observations have revealed stars where the abundance distributions cannot be described by the aforementioned processes and for this reason the astrophysical i process was introduced (i for intermediate between s and r). While we...
Photonuclear reactions play an essential role in nucleosynthesis taking place in all sites, e.g., stars, novae, and interstellar gas media. Especially important these reactions are for formation of isotopes heavier than iron. The proton-rich p-nuclei, such as $^{114}Sn$, and $^{113}In$, can be created only via a complex sequence of radiative processes, involving both emission and capture of...
Although about 90$\%$ and 50$\%$ of the solar-system Cu and Zn abundances are presumed to originate from the slow neutron-capture process (weak $\textit{s}$-process) during core He and shell C burning in massive stars, their stellar conditions are still poor known. This is because $^{63}$Ni (t$_{1/2}$=101.2$\pm$1.5yr) takes the key as a bottleneck for the synthesis of these nuclei in the...
Cross-sections for neutron-induced interactions with molybdenum, in particular for the neutron capture reaction, play a significant role in various fields ranging from nuclear astrophysics to safety assessment of conventional nuclear power plants and the development of innovative technologies. Molybdenum is found in pre-solar silicon carbide (SiC) grains and an accurate knowledge of its...
RAON aims to produce rare isotope beams through proton-induced fission of uranium-238. In this study, we utilize the Langevin method to predict the mass distribution by plotting trajectories based on the potential surface of compound nuclei, integrating the Liquid Drop Model (LDM) and the Shell model (SM). To enhance the shell effect at high excitation energy, we employ a multi-chance fission...
The stellar (n, γ) cross section data for the mass numbers around A ≈ 160 are of key importance to nucleosynthesis in the main component of the slow neutron capture process, which occurs in the thermally pulsing asymptotic giant branch (TP–AGB). The new measurement of (n, γ) cross sections for 159Tb was performed using the C6D6 detector system at the back streaming white neutron beam line...
It is widely accepted that the slow (s-process) and rapid (r-process) scenarios of neutron captures contribute to the solar abundances of trans-Fe nuclei.
The yields of up-to-date and totally independent models for s- and r-process show a general good and complementary agreement in reproducing the Solar System abundances. However, some local discrepancies do occur and this fact could hint to...
The abundance of 26Al carries a special role in astrophysics, since it probes active nucleosynthesis in the MilkyWay and constrains the Galactic core-collapse supernovae rate. It is estimated through
the detection of the 1809 keV-line and from the superabundance of 26Mg in comparison with the most abundant Mg isotope (A=24) in meteorites. For this reason, high precision is necessary also in...
The observed surface abundance distribution of Carbon-enhanced metal-poor (CEMP) r/s-stars suggests that these stars have been polluted by an intermediate neutron-capture process (the so-called i-process) occurring at intermediate neutron densities between the r- and s-processes. Triggered by the ingestion of protons inside a convective He-burning zone, the i-process could be hosted in several...
The reaction rate of the carbon fusion reaction is one of the basic inputs in the stellar model to understand the final stages of the massive star evolution. However, this reaction rate is yet uncertain because it depends on the extrapolation methods. The cross-section measurement for this reaction is challenging because the energy range relevant to the stellar evolution is much below the...
The COREA (Carbon Oxygen Reaction Experiment with Active-target TPC) is an experiment to measure the precise cross-section of the 12C(α,𝛄)16O reaction in stellar nucleosynthesis. The reaction rate of 12C(α,𝛄)16O determines the 12C/16O abundance ratio in the universe and the entire scenario of the stellar nucleosynthesis after the helium burning up to the Fe core in the last years of stellar...
