REACTOR NEUTRON CAPTURE CROSS SECTION OF 51-DAY Sr89

The neutron capture cross section of Sr89 has been measured by an activation method. Naturally occurring strontium was irradiated in different high flux positions in the NRX reactor at Chalk River and the amount of Sr90 formed by successive neutron capture in Sr88 was determined by separating and measuring its daughter Y90. Using values of 36.6 and 0.005 barns for the respective neutron capture cross sections of Co59 and Sr88, the capture cross section of Sr89 for reactor spectrum neutrons was found to be 0.49 ± 0.10 barn.

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THERMAL NEUTRON CAPTURE CROSS-SECTION OF Na23 AND Mn55

Canadian Journal of Chemistry ◽

10.1139/v53-029 ◽

1953 ◽

Vol 31 (3) ◽

pp. 204-206 ◽

Cited By ~ 12

Author(s):

Rosalie M. Bartholomew ◽

R. C. Hawkings ◽

W. F. Merritt ◽

L. Yaffe

Keyword(s):

Thermal Neutron ◽

Cross Section ◽

Cross Sections ◽

Neutron Capture ◽

Half Life ◽

Capture Cross Section ◽

Thermal Neutron Capture ◽

Capture Cross ◽

Neutron Capture Cross Section ◽

Capture Cross Sections

The thermal neutron capture cross sections of Na23 and Mn55 have been determined using the activation method. The values are 0.53 ± 0.03 and 12.7 ± 0.3 barns respectively with respect to σAul97 = 93 barns. These agree well with recent pile oscillator results. The half-life for Mn56 is found to be 2.576 ± 0.002 hr.

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Neutron capture cross section measurements of 232Th in the 30-600 keV energy range

HNPS Proceedings ◽

10.12681/hnps.2187 ◽

2019 ◽

Vol 10 ◽

pp. 173

Author(s):

D. Karamanis ◽

M. Petit ◽

S. Andriamonje ◽

G. Barreau ◽

M. Bercion ◽

...

Keyword(s):

Energy Range ◽

Cross Section ◽

Cross Sections ◽

Neutron Capture ◽

Energy Region ◽

Preliminary Analysis ◽

Capture Cross Section ◽

Capture Cross ◽

Neutron Capture Cross Section ◽

Capture Cross Sections

Neutron capture cross sections of 232T/i have been measured relative to 197Au in the energy region from 30 keV to 600 keV. The neutron source was the reaction 7Li(p, n) produced on the 4 MV Van de Graaff Accelerator of the Centre d' Etudes Nucléaires de Bordeaux (CENBG). Preliminary analysis of the measurements indicates that the cross sections are closer to the JENDL database values.

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Measurement of the 244Cm capture cross sections at both CERN n_TOF experimental areas

EPJ Web of Conferences ◽

10.1051/epjconf/202023901034 ◽

2020 ◽

Vol 239 ◽

pp. 01034

Author(s):

V. Alcayne ◽

E. Mendoza ◽

D Cano-Ott ◽

A. Kimura ◽

O. Aberle ◽

...

Keyword(s):

Experimental Data ◽

Cross Section ◽

Cross Sections ◽

Neutron Capture ◽

Capture Cross Section ◽

Capture Cross ◽

Neutron Capture Cross Section ◽

Experimental Area ◽

High Burnup ◽

Capture Cross Sections

Accurate neutron capture cross section data for minor actinides (MAs) are required to estimate the production and transmutation rates of MAs in light water reactors with a high burnup, critical fast reactors like Gen-IV systems and other innovative reactor systems such as accelerator driven systems (ADS). Capture reactions of 244Cm open the path for the formation of heavier Cm isotopes and of heavier elements such as Bk and Cf. In addition, 244Cm shares nearly 50% of the total actinide decay heat in irradiated reactor fuels with a high burnup, even after three years of cooling. Experimental data for this isotope are very scarce due to the difficulties of providing isotopically enriched samples and because the high intrinsic activity of the samples requires the use of neutron facilities with high instantaneous flux. The only two previous experimental data sets for this neutron capture cross section have been obtained in 1969 using a nuclear explosion and, more recently, at J-PARC in 2010. The neutron capture cross sections have been measured at n_TOF with the same samples that the previous experiments in J-PARC. The samples were measured at n_TOF Experimental Area 2 (EAR-2) with three C6D6 detectors and also in Experimental Area 1 (EAR-1) with the Total Absorption Calorimeter (TAC). Preliminary results assessing the quality and limitations of these new experimental datasets are presented for the experiments in both areas. Preliminary yields of both measurements will be compared with evaluated libraries for the first time.

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The 154Gd neutron capture cross section measured at the n_TOF facility and its astrophysical implications

EPJ Web of Conferences ◽

10.1051/epjconf/202023907003 ◽

2020 ◽

Vol 239 ◽

pp. 07003

Author(s):

M. Mastromarco ◽

A. Mazzone ◽

C. Massimi ◽

S. Cristallo ◽

N. Colonna ◽

...

Keyword(s):

Cross Section ◽

Cross Sections ◽

Neutron Capture ◽

Nuclear Physics ◽

Capture Cross Section ◽

Close Correlation ◽

Capture Cross ◽

Neutron Capture Cross Section ◽

Capture Process ◽

Process Region

The (n, γ) cross sections of the gadolinium isotopes play an important role in the study of the stellar nucleosynthesis. In particular, among the isotopes heavier than Fe, 154Gd together with 152Gd have the peculiarity to be mainly produced by the slow capture process, the so-called s-process, since they are shielded against the β-decay chains from the r-process region by their stable samarium isobars. Such a quasi pure s-process origin makes them crucial for testing the robustness of stellar models in galactic chemical evolution (GCE). According to recent models, the 154Gd and 152Gd abundances are expected to be 15-20% lower than the reference un-branched s-process 150Sm isotope. The close correlation between stellar abundances and neutron capture cross sections prompted for an accurate measurement of 154Gd cross section in order to reduce the uncertainty attributable to nuclear physics input and eventually rule out one of the possible causes of present discrepancies between observation and model predictions. To this end, the neutron capture cross section of 154Gd was measured in a wide neutron energy range (from thermal up to some keV) with high resolution in the first experimental area of the neutron time-of-flight facility n_TOF (EAR1) at CERN. In this contribution, after a brief description of the motivation and of the experimental setup used in the measurement, the preliminary results of the 154Gd neutron capture reaction as well as their astrophysical implications are presented.

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Die chemische Fixierung von Kryptonisotopen in Zeolith 5 A — Voraussetzung für die Messung von 25 keV Neutroneneinfang- querschnitten mit der Aktivierungstechnik/ The Chemical Fixation of Kr Isotopes in Zeolite 5 A.- Prerequisite for the Determination of 25 keV Neutron Capture Cross Sections with the Activation Method

Zeitschrift für Naturforschung A ◽

10.1515/zna-1983-0702 ◽

1983 ◽

Vol 38 (7) ◽

pp. 712-718 ◽

Cited By ~ 4

Author(s):

R.-D. Penzhorn ◽

G. Walter ◽

H. Beer

Keyword(s):

Cross Section ◽

Cross Sections ◽

Neutron Capture ◽

Capture Cross Section ◽

Heavy Elements ◽

Chemical Fixation ◽

Capture Cross ◽

Stellar Nucleosynthesis ◽

Capture Cross Sections

AbstractBy chemical fixation of Kr in zeolite 5 A adequate samples can be obtained to determine the capture cross section of reactions such as 84 Kr (n, γ) 85Krm and 86Kr (n, γ) 87Kr. The employed zeolite loading was of the order 52-66 [cm3 STP Kr/g zeolite]. The capture cross section of the reaction 84Kr(n, γ) 85Krm was determined at thermal and 25 keV neutron energy. The value obtained at 25 keV is of relevance to the stellar nucleosynthesis of heavy elements.

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