A5014836125- Nuclear Physics and Applications
- Nuclear reactor physics and engineering
- Nuclear physics research studies
- Radiation Therapy and Dosimetry
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Astronomical and nuclear sciences
- Nuclear Materials and Properties
Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear
2012-2024
Over the years, Maxwellian Averaged Cross Sections (MACS) have been measured by neutron activation, providing a energy spectrum resembling one found inside stars. Recently, new method has proposed to produce stellar spectra at different temperatures (a Maxwell–Boltzmann distribution), employing 7Li(p,n)7Be reaction. The is based on idea of shaping proton beam shape spectrum. This was applied obtain well-reproduced (MBNS) kT=28 keV. An initial 3170 keV and an aluminum foil as shaper were...
Abstract A few years ago, we theoretically studied the production of a stellar neutron spectrum at kT = 30 keV using shaped proton beam impinging on thick lithium target. Here, first measure distribution to better control produced spectrum. Then, forward-emitted angle-integrated 7 Li(p,n) Be reaction via time-of-flight spectrometry with such distribution. The result resembles keV. This method avoids in activation experiments need for correction. In case spherical samples, no knowledge...
The forward-emitted low energy tail of the neutron spectrum generated by $^{7}\mathrm{Li}(p,n)^{7}\mathrm{Be}$ reaction on a thick target at proton 1893.6 keV was measured time-of-flight spectroscopy. measurement performed BELINA (Beam Line for Nuclear Astrophysics) Laboratori Nazionali di Legnaro. Using kinematics and lithium stopping power shape excitation function is calculated from spectrum. Good agreement with two reported measurements found. Our data, along previous measurements, are...
LENOS is a new facility under development at Laboratori Nazionali di Legnaro (LNL). It based on technic for neutron beam shaping in accelerator sources. The main advantage of this method to be able shape the primary charged-particle defined energy distribution that, impinging producing target, generates desired spectra sample position. Together with proton distribution, other degrees freedom are used obtain spectra, e.g. angular produced neutrons, nuclear reactions production, and...
Background: The $^{7}\mathrm{Li}(p,n)^{7}\mathrm{Be}$ reaction is one of the most used nuclear for accelerator-based neutron sources. There are few experimental cross section data in double-value energy region and they discrepant, as yields.Purpose: We derive section, measure with small uncertainty $^{197}\mathrm{Au}(n,\ensuremath{\gamma})^{198}\mathrm{Au}$ spectrum-averaged at around 30 keV.Method: By irradiating Li metal targets over proton range 1879 to 1960 keV, thick target yields were...
We present some open questions in nucleosynthesis focused on the measurement of relevant neutron capture cross-sections and new experimental methods. review recent 63Ni(n,γ) experiment carried out at n_TOF facility CERN its astrophysical implications as well future experiments opportunities n_TOF. argue improvements by activation arising from a method for generation stellar spectra. show preliminary results validation method. discuss 181Ta(n,γ) cross-section measured with this Finally, we...
To calculate the reaction rate in neutron capture processes it is common to work with Maxwellian Average Cross Section (MACS), defined as scaled by most probable velocity of Maxwell-Boltzmann distribution. For MACS determination lower uncertainties, need a spectrum similar possible stellar one motivates this work. At CN Van der Graaff accelerator LNLINFN laboratories, an experimental measurement performed produce 28 keV thermal temperature. The time-of-flight spectrometry implemented...
Abstract In neutron time-of-flight (nTOF) experiments a pulsed beam travels predetermined distance before reaching the sample under examination. The problem of reconstructing primary spectrum from measured one with this technique is discussed in work. A solution presented employing response matrix detector and an unfolding procedure.
In the present experiment we measure forward-emitted angle-integrated neutron spectrum of 7Li(p,n)7Be reaction via time-of-flight spectrometry. The proton beam is shaped to a Gaussian-like distribution with energies close threshold upstream thick lithium target. resembles Maxwellian or stellar at kT=30 keV.