On the Experimental Investigation of the Angular Distributions in the Reaction 112Cd(p,γ)113In

Some of the mid–weight nuclei lie in the region of the isotopic chart where the astrophysical p-process has a prominent role in the nucleosynthetic scenarios. Experimentally deduced reaction cross section data can provide stringent tests for the astrophysical models, especially at low energies. In this framework, the reaction 112Cd(p,γ)113In has been studied experimentally at four proton beam energies 2.8 ≤ Ep≤ 3.4 MeV, partly inside the astrophysically interesting Gamow window. Proton beams were provided by the 5.5 MV T11 Van de Graaff Tandem Accelerator of the Institute of Nuclear Physics of the National Center for Scientific Research (NCSR) “Demokritos”. In–beam spectroscopy was carried out with an array of four HPGe detectors sitting on a rotating table. In total, eight (8) different angles were used to record gamma–ray spectra. Special focus was given on constructing the angular distribution of each gamma–ray feeding the ground state of 113In directly, so as to determine the reaction cross sections from the in–beam data, exclusively. The resulting cross sections were compared to Hauser–Feshbach calculations using the code TALYS v1.9.

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Measurement of the 241Am(n,2n)240Am cross section at 17.5 MeV

HNPS Proceedings ◽

10.12681/hnps.2024 ◽

2019 ◽

Vol 21 ◽

pp. 160

Author(s):

A. Kalamara ◽

R. Vlastou ◽

M. Diakaki ◽

M. Kokkoris ◽

M. Anastasiou ◽

...

Keyword(s):

Cross Section ◽

Neutron Beam ◽

Cross Sections ◽

Reaction Cross ◽

Activation Technique ◽

Tandem Accelerator ◽

Hpge Detectors ◽

Reaction Cross Sections ◽

Reference Reaction ◽

High Radioactivity

The 241Am(n,2n)240Am reaction cross section has been measured at neutron beam energy 17.5 MeV, relative to the 27Al(n,α)24Na, 197Au(n,2n)196Au and 93Nb(n,2n)92mNb reference reaction cross sections, using the activation technique. The irradiation was carried out at the Van der Graaff 5.5 MV Tandem accelerator laboratory of NCSR “Demokritos” with monoenergetic neutron beam provided by means of the 3H(d,n)4He reaction, implementing a new Ti-tritiated target. The high purity Am target has been constructed at IRMM, Geel, Belgium and consisted of 40 mg 241Am in the form of AmO2 pressed into pellet with Al2O3 and encapsulated into Al container. Due to this high radioactivity (5 GBq), the Am target was enclosed in a Pb container for safety reasons. After the end of the irradiation, the activity induced by the neutron beam at the target and reference foils, was measured off-line by two 100%, a 50% and a 16% relative efficiency, HPGe detectors.

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14.8 MeV Neutron Activation Cross Section Measurements for Ge Isotopes

Journal of Scientific Research ◽

10.3329/jsr.v1i2.1532 ◽

2009 ◽

Vol 1 (2) ◽

pp. 173-181 ◽

Cited By ~ 3

Author(s):

M. M. Haque ◽

M. T. Islam ◽

M. A. Hafiz ◽

R. U. Miah ◽

M. S. Uddin

Keyword(s):

Cross Section ◽

Cross Sections ◽

Gamma Ray ◽

Reaction Cross ◽

Activation Cross Section ◽

Section Data ◽

Gamma Ray Spectroscopy ◽

24Na Reaction ◽

The Cross ◽

Good Agreement

The cross sections of Ge isotopes were measured with the activation method at 14.8 MeV neutron energy. The quasi-monoenergetic neutron beams were produced via the 3H(d,n)4He reaction at the 150 kV J-25 neutron generator of INST, AERE. The characteristics γ-lines of the product nuclei were measured with a closed end coaxial 17.5 cm2 high purity germanium (HPGe) detector gamma ray spectroscopy. The cross sections were determined with reference to the known 27Al(n,α)24Na reaction. Cross section data are presented for 72Ge(n,p)72Ga, 74Ge(n,α)71mZn and 76Ge(n,2n)75m+gGe reactions. The cross section values obtained for the above reactions were 24.78±1.75 mb, 1.69±0.11 mb and 860±50 mb, respectively. The results obtained were compared with the values reported in literature as well as theoretical calculation performed by the statistical code SINCROS-II. The experimental data were found fairly in good agreement with the calculated and literature data. Keywords: Activation cross section; Neutron induced reaction; Gamma-ray spectroscopy; 14.8 MeV. © 2009 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v1i2.1532

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Development of the ELISSA array: prototype testing at Laboratori Nazionali del Sud

EPJ Web of Conferences ◽

10.1051/epjconf/201818402006 ◽

2018 ◽

Vol 184 ◽

pp. 02006

Author(s):

G. L. Guardo ◽

A. Anzalone ◽

D. Balabanski ◽

S. Chesnevskaya ◽

W. Crucillá ◽

...

Keyword(s):

Cross Sections ◽

Nuclear Physics ◽

Gamma Ray ◽

Nuclear Astrophysics ◽

Angular Distributions ◽

Silicon Strip Detector ◽

Position Resolution ◽

Wide Energy ◽

Good Energy ◽

Better Than

The Extreme Light Infrastructure-Nuclear Physics (ELI-NP) facility, underconstruction in Magurele near Bucharest in Romania, will provide high-intensity andhigh-resolution gamma ray beams that can be used to address hotly debated problems in nuclear astrophysics, such as the accurate measurements of the cross sections of the24Mg(γ,α)20Ne reaction For this purpose, a silicon strip detector array (named ELISSA) will be realized in acommon effort by ELI-NP and Laboratori Nazionali del Sud (INFN-LNS), in order to measure excitation functions and angular distributions over a wide energy and angular range. A prototype of ELISSA was built and tested at INFN-LNS in Catania (Italy) with the support of ELI-NP. In this occasion, we have carried out experiments with alpha sources and with a 11 MeV 7Li beam that show up a very good energy resolution (better than 1%) and very good position resolution, of the order of 1 mm. Moreover, a threshold of 150 keV can be easily achieved with no cooling.

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A simple angle integration method for the determination of capture reaction cross sections

HNPS Proceedings ◽

10.12681/hnps.1855 ◽

2019 ◽

Vol 24 ◽

pp. 129

Author(s):

V. Michalopoulou-Petropoulou ◽

V. Lagaki ◽

M. Axiotis ◽

V. Foteinou ◽

A. Lagoyannis ◽

...

Keyword(s):

Cross Section ◽

Cross Sections ◽

Integration Method ◽

Reaction Cross ◽

Angular Distributions ◽

Distribution Method ◽

Hpge Detectors ◽

Secondary Transitions ◽

Reaction Cross Sections

In order to determine the cross section of a reaction by the angular distribution method, it is essential to calculate the angular distributions of all secondary transitions that lead to the ground state. This is achieved by analysing spectra from HPGe detectors at various detection angles, which is a time consuming process. In this work, a simpler angle integration method is presented that allows to determine cross sections of capture reactions by measuring spectra at fewer detection angles.

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The feasibility of measuring the nuclear reaction cross sections at energies of several KeV in a target under laser compression

Laser and Particle Beams ◽

10.1017/s026303460000286x ◽

1987 ◽

Vol 5 (2) ◽

pp. 399-404 ◽

Cited By ~ 1

Author(s):

V. I. Kukulin ◽

V. M. Krasnopol'sky ◽

V. T. Voronchev

Keyword(s):

Nuclear Reaction ◽

Cross Sections ◽

Nuclear Reactions ◽

Velocity Distribution Function ◽

Reaction Cross ◽

Straightforward Method ◽

Energy Behaviour ◽

Low Energies ◽

Ion Velocity Distribution Function ◽

Reaction Cross Sections

The work proposes a straightforward method for determining the nuclear reaction cross sections at extremely low energies (E ≃ 1–100 keV) on the basis of the measurements of the relative yield of fast particles which are products of the nuclear reactions in a target under laser compression. On the other hand, the proposed method makes it possible to find the averaged form of the ion velocity distribution function if the low-energy behaviour of the respective cross sections is known.

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Measurements of neutron-induced light-charged particle emission reactions

EPJ Web of Conferences ◽

10.1051/epjconf/202023901001 ◽

2020 ◽

Vol 239 ◽

pp. 01001

Author(s):

Guohui Zhang ◽

Huaiyong Bai ◽

Haoyu Jiang ◽

Zengqi Cui ◽

Yi Lu ◽

...

Keyword(s):

Neutron Source ◽

Neutron Energy ◽

Cross Sections ◽

Energy Region ◽

Nuclear Research ◽

Reaction Cross ◽

Tandem Accelerator ◽

Peking University ◽

Three Body ◽

Charged Particle Emission

In the past two decades cooperating with Frank Laboratory of Neutron Physics (FLNP), Joint Institute for Nuclear Research (JINR) measurements of (n, α) reaction cross sections for 6Li, 10B, 25Mg, 39K, 40Ca, 54,56,57 Fe, 58Ni, 63Cu, 64,67 Zn, 95Mo, 143Nd and 147,149 Sm nuclei were performed in the MeV neutron energy region based on the 4.5 MV Van de Graaff accelerator at Peking University. In recent years, our measurements were extended in three aspects. Firstly, measurements were expanded from two-body reactions to three-body reactions such as 10B (n, t2 α). Secondly, the neutron energy region was extended from below 8 MeV to 8 - 11 MeV by using the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE), with which cross sections of 54,56 Fe(n, α)53,51Cr reactions were measured. Thirdly, based on the newly-built China Spallation Neutron Source (CSNS) Back-n WNS (White Neutron Source), differential and angle-integrated cross sections for 6Li(n, t) and 10B(n, α) reactions were measured in the neutron energy region from 1 eV to 3 MeV.

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Precision measurements on oxygen formation in stellar helium burning with gamma-ray beams and a Time Projection Chamber

10.21203/rs.3.rs-291379/v1 ◽

2021 ◽

Author(s):

Robin Smith ◽

Moshe Gai ◽

Sarah Stern ◽

Deran Schweitzer ◽

Mohammad Ahmed

Keyword(s):

Time Projection Chamber ◽

Gamma Ray ◽

Nuclear Reactions ◽

Angular Distributions ◽

Helium Burning ◽

Low Energies ◽

Important Input ◽

Novel Method ◽

Time Projection ◽

First Time

Abstract Stellar Evolution theory relies on our knowledge of nuclear reactions, with the carbon/oxygen (C/O) ratio, at the end of helium burning, being the single most important input. However, the C/O ratio is still not known with sufficient accuracy, due to large uncertainties in the cross section for the fusion of helium with 12C to form 16O, denoted as the 12C(α,γ)16O reaction. We present initial results at moderately low energies using a novel method, which is significantly different from the experimental efforts of the past four decades. Precise angular distributions of the 12C(α,γ)16O reaction were obtained by measuring the inverse 16O(γ,α)12C reaction with gamma-beams and a Time Projection Chamber detector. These allowed us to measure, for the first time, the interference angle of the l = 1 and 2 partial waves contributing to this reaction (φ12), which agrees with predictions based on the unitarity of the scattering matrix.

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Attempted study of the 237Np(n,2n)236Np reaction cross section at 9.5 MeV

HNPS Proceedings ◽

10.12681/hnps.2544 ◽

2019 ◽

Vol 18 ◽

pp. 101

Author(s):

M. Diakaki ◽

R. Vlastou ◽

M. Kokkoris ◽

C. T. Papadopoulos ◽

A. Tsinganis ◽

...

Keyword(s):

Cross Section ◽

Gamma Ray ◽

Gamma Spectroscopy ◽

Reaction Cross ◽

Activation Technique ◽

Incident Neutron ◽

Incident Neutron Energy ◽

Tandem Accelerator ◽

Section Measurement ◽

High Gamma

The cross section measurement of the 237Np(n,2n)236Np reaction has been attempted at an incident neutron energy of 9.5 MeV by means of the activation technique. The neutron beam was produced via the 2H(d,n)3Ηe reaction at the VdG Tandem accelerator of NCSR “Demokritos”. It is the second time that this measurement has been tried with a gamma spectroscopy method and the difficulties faced due to the high gamma ray background produced by the sample itself and the fission fragments produced by the irradiation, in combination with the very low intensity of the gamma ray of interest are being reported.

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Experimental measurement of the 12C+16O fusion cross sections at astrophysical energies

EPJ Web of Conferences ◽

10.1051/epjconf/201817804008 ◽

2018 ◽

Vol 178 ◽

pp. 04008

Author(s):

X. Fang ◽

W. P. Tan ◽

M. Beard ◽

R. J. deBoer ◽

G. Gilardy ◽

...

Keyword(s):

Cross Sections ◽

Center Of Mass ◽

Model Calculations ◽

Center Of Mass Energy ◽

Pure Graphite ◽

S Factor ◽

Hpge Detectors ◽

Low Energies ◽

The University

The total cross sections of the 12C+16O fusion have been experimentally determined at low energies to investigate the role of this reaction during late stellar evolution burning phases. A high-intensity oxygen beam was produced by the 5MV pelletron accelerator at the University of Notre Dame impinging on a thick ultra-pure graphite target. Protons and γ-rays were measured simultaneously in the center-of-mass energy range from 3.64 to 5.01 MeV, using strip silicon and HPGe detectors. Statistical model calculations were employed to interpret the experimental results. A new broad resonance-like structure is observed for the 12C+16O reaction, and a decreasing trend of its S-factor towards low energies is found.

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