Current opinion

, Volume: 10( 5) DOI: 10.37532/2320-6756.2022.10(5).278

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In Today's Nuclear Astrophysics, Critical Reactions Exist

*Correspondence:

Divya Jangid
Department of Biotechnology and Microbiology, MIET, Meerut, India
E-mail: jangiddivya615@gmail.com

Abstract

Nuclear astrophysics is a thriving field at the crossroads of nuclear physics and astrophysics, encompassing nuclear physics, astrophysics, astronomy, and computer science research. This is not a review paper. Its purpose is to provide a personal viewpoint on current trends in nuclear astrophysics and the significance of nuclear physics in this field. Nuclear structure, low energy reaction rates, nuclear masses, and decay rates all contribute to the Nuclear Physics input. The most important component of the required nuclear physics input is often thought to be low energy reaction rates; however, in this article, we take a broader approach and present an overview of the close correlation between various nuclear structure aspects and their impact on nuclear astrophysics.

Keywords

Nuclear structure; Nuclear reactions; Nuclear astrophysics

Introduction

A new underground accelerator laboratory is now being built for studying low-energy nuclear reaction cross sections relevant to nuclear astrophysics. At the Sanford Underground Research Facility (SURF) in Lead, South Dakota, the Compact Accelerator System for Performing Astrophysical Research (CASPAR) is currently being installed. The main focus of this new system is on stellar neutron source measurements, which govern the creation of heavy elements in stars via the weak and main s-processes [1].

Because it shows phenomena ranging from the massive scale structure of the cosmos to the small scale of nuclear physics and particle physics, the universe has recently attracted scientists from numerous domains. Nuclear reactions are an important part of the universe's evolution. In stars surrounded by a strong gravitational pull, nuclei interact with one another. As a result, the dynamical behaviour of nuclei in the universe is similar to that of a gravitational frying pot.

As a large and diverse field of research, nuclear astronomy can be thought of as a magnifier of the impact of tiny processes on the evolution of macroscopic events. Understanding the nucleosynthesis processes that occur in the cosmos, as well as simulating the corresponding star and explosive burning scenarios, is one of the key goals in Nuclear Astrophysics. These simulations rely heavily on nuclear physics input, which determines the time scale for all stellar dynamic processes from giga-years of stellar evolution to milli-seconds of stellar explosions and is the source of most of the signatures we have for interpreting these events, such as stellar luminosities, elemental and isotopic abundances, and neutrino flux from distant supernovae [2-4].

Nuclear astrophysics is the study of how nuclear processes generate energy during the evolution of stars, and how the rich distribution of nuclides observed on the earth, on the moon, in meteorites and cosmic rays, and in stellar atmospheres is produced from primordial hydrogen and helium in the expanding universe. Knowledge of nuclear reaction cross sections at very low collision energy corresponding to the temperatures relevant at the astrophysical sites under investigation is a prerequisite for a consistent explanation in terms of star burning chains [5].

Many stellar events and their related nucleosynthesis, including as core-collapse and thermonuclear supernovae, novae, x-ray busters, and mass-accreting neutron stars in binary systems, rely on short-lived exotic nuclei. Radioactive ion-beam facilities are required to create such nuclei and analyse their properties. While the short-lived nuclei on the neutron-deficient side of the nuclei chart are often accessible at current experimental facilities, albeit not always with the beam intensities required, the extremely neutron-rich nuclei required for understanding the astrophysical r-process synthesis of heavy elements in the Universe must, in most cases, wait for next-generation radioactive ion-beam facilities [3].

Nuclear data are also used to interpret new observations made by ground-based observatories like the Keck and European Southern Observatory (ESO) Very Large Telescopes, as well as space-based observatories like the Hubble Space Telescope and the Chandra X-Ray Observatory, and large subterranean detectors like the Sudbury Neutrino Observatory and Super-Kamiokande. To refine astrophysical models and comprehend the latest findings, more thorough and precise nuclear physics measurements are required.

In most astrophysical settings, nuclear processes are the primary source of energy and element synthesis. In addition to a strong grasp of the underlying hydrodynamics, radiation transport, and other aspects of stellar evolution, astrophysical models of these environments require the rate and energy release of the corresponding nuclear processes as important inputs. As a result, measurements of reaction cross sections, nuclear masses, and other nuclear structural features serve as a crucial empirical foundation for astrophysical models.

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