Related Experiment Video
Updated: Jun 30, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
8.6K
Ge( ) cross section below 70 keV measured at n_TOF CERN
C Lederer-Woods1, O Aberle2, J Andrzejewski3
1School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
The European Physical Journal. A, Hadrons and Nuclei
|December 14, 2022
Summary
We measured neutron capture cross sections for Germanium-70 (⁷⁰Ge) to understand its production in stars. Our new data aligns with previous experiments after re-normalizing based on updated cross section references.
Area of Science:
- Nuclear astrophysics
- Stellar nucleosynthesis
- Neutron capture reactions
Background:
- Germanium-70 (⁷⁰Ge) production is crucial for understanding the slow neutron capture process (s-process) in stars.
- Accurate neutron capture cross sections are needed for astrophysical models.
Purpose of the Study:
- To present new resonance data for neutron capture reactions on ⁷⁰Ge below 70 keV.
- To calculate Maxwellian averaged cross sections for ⁷⁰Ge.
Main Methods:
- Measurement of neutron capture cross sections on ⁷⁰Ge using resonance data.
- Calculation of Maxwellian averaged cross sections by combining new data with evaluated cross sections.
Main Results:
- New resonance data for ⁷⁰Ge(n, γ) reactions below 70 keV neutron energy was obtained.
- Calculated stellar cross sections for ⁷⁰Ge are in agreement with a previous activation measurement (Marganiec et al.) after re-normalization.
Conclusions:
- The study provides crucial data for ⁷⁰Ge production during the s-process.
- The findings validate previous experimental results with updated cross section references.
More Related Videos
Related Concept Videos
02:13Nuclear Binding Energy
The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect indicates a “loss” in mass of 4.0331 amu – 4.0026 amu = 0.0305 amu. The loss in mass accompanying the formation of an atom from protons, neutrons, and electrons is due to the conversion of that mass into energy that is evolved as the atom forms. The nuclear binding energy is the energy produced when the atoms’ nucleons are bound together;...
03:20Nuclear Transmutation
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons being...
01:06Nuclear Overhauser Enhancement (NOE)
Irradiation of a spin-active nucleus causes an increase or decrease in the signal intensity of neighboring nuclei that are not necessarily chemically bonded or involved in J-coupling. This phenomenon, called the nuclear Overhauser enhancement (NOE), results from through-space interactions between the nuclear spins. The NOE effect decreases with increasing internuclear distance and is generally not observed beyond 4 angstroms. In NOE, dipole-dipole interactions between neighboring spin-active...
01:19Thomson's e/m Experiment
In a beam of charged particles created by a heated cathode, the particles move at different speeds. However, many applications need a beam with uniform particle speeds. An arrangement known as a velocity selector uses electric and magnetic fields to pick particles with a particular speed from the beam.
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The magnetic...
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The magnetic...
01:13Atomic Absorption Spectroscopy: Radiation and Light Sources
Atomic absorption spectroscopy (AAS) relies on the Beer-Lambert law, which requires that the radiation source emits a narrow range of wavelengths to match the absorption characteristics of the analyte atom. The primary criteria for choosing an appropriate radiation source in AAS is to provide a precise and intense emission at specific wavelengths that will allow accurate detection of the analyte.
Two common narrow-range 'line' sources used in AAS are hollow-cathode lamps (HCLs) and...
Two common narrow-range 'line' sources used in AAS are hollow-cathode lamps (HCLs) and...
01:22Atomic Emission Spectroscopy: Instrumentation
The instrumentation of atomic emission spectrometry (AES) involves various components, including atomization devices that convert samples into gas-phase atoms and ions. There are two main types of atomization devices: continuous and discrete atomizers. Continuous atomizers, like plasmas and flames, introduce samples in a constant stream, while discrete atomizers inject individual samples using syringes or autosamplers. The most common discrete atomizer is the electrothermal atomizer.