In recent years, new astronomical observations have revealed abundance patterns that cannot be explained by the classic nucleosynthesis picture. A description of the synthesis of heavy elements using only the s, r and p processes is not adequate anymore and for this reason new scenarios had to be proposed. In this talk I will focus on neutron-capture processes that involve exotic nuclei,...
Observations of astrophysical phenomena, such as the luminosity of X-ray bursts and the abundance pattern of stars, can be explained by nuclear reactions occurring in the stars. It is well known that the nuclear properties of isotopes involved in the nuclear reactions have a direct impact on stellar evolution, such as energy generation, the nucleosynthesis path, and final abundance...
Albeit recent development of dynamical approaches to the nuclear fission phenomena has been significantly improving our understanding of this complex nuclear reaction mechanism, conventional fission models in the statistical Hauser-Feshbach theory remain the extremely simplified fission barrier model with the WKB approximation. Due to the inherent deficiencies in calculating nuclear fission...
To constrain the nu-p process, we studied the $^{56}$Ni(n,p) reaction by directly measuring the cross section on the radioactive $^{56}$Ni (a half-life of 6 days) at Los Alamos Neutron Science Center. This reaction has been identified as one of critical reactions for understanding the heavy element production in core-collapse supernovae. The radioactive $^{56}$Ni was produced by irradiating...
A neutron star can accrete hydrogen-rich material from a low-mass binary companion star. This can lead to periodic thermonuclear runaways, which manifests as a Type I X-ray bursts detected by space-based telescopes. Sensitivity studies have shown that ${}^{15}\text{O}(\alpha, \gamma){}^{19}\text{Ne}$ carries one of the most important reaction rate uncertainties affecting the modeling of the...
We investigated $^{10}$Be production mechanism in the neutrino-process in the core collapsing supernova (CCSN) by including recent updated nuclear reactions relevant to dominant production and destruction of $^{10}$Be. They involve production reactions by neutrinos $^{12}$C and $^{16}$O and other production reactions $^{10}$B(n,p)$^{10}$Be, $^{11}$Be($\gamma$, n)$^{10}$Be. Inverse reactions of...
Globular clusters are key grounds for models of stellar evolution and early stages of the formation of galaxies. Abundance anomalies observed in the globular cluster NGC 2419, such as the enhancement of potassium and depletion of magnesium [1] can be explained in terms of an earlier generation of stars polluting the presently observed stars [2]. However, the nature and the properties of the...
Asymptotic giant branch (AGB) stars are a late evolutionary phase of low- and intermediate-mass star. They are typified by rapid mass loss through a stellar wind rich in molecular diversity, which is also a key site of dust formation in the universe. Their stellar winds provide a unique opportunity to study the isotopic ratios of various key atomic species that form molecules and whose...
A detailed analysis of nucleosynthesis in the environment of xenon (Z=54) may provide a valuable insight into the interior of stars. The stable isotopes of xenon are produced in a variety of astrophysical environments. The different combinations of nucleosynthetic pathways are: $\gamma$-process for $^{124}$Xe and $^{126}$Xe, $\gamma$- and s-processes for $^{128}$Xe,
s-process for $^{130}$Xe,...
For a long time, 1D LTE (local thermal equilibrium) modelling has been the main approach in spectroscopic abundance determination of elements. However, the recent computational advancements has allowed us to explore both 1D NLTE (non-LTE) and 3D NLTE effects on elemental abundances. In my presentation, I will begin by briefly revisiting the known s-process elements Strontium (Sr) (Bergemann et...
