|   | 
Details
   web
Records
Author Grieger, M.; Hensel, T.; Agramunt, J.; Bemmerer, D.; Degering, D.; Dillmann, I.; Fraile, L.M.; Jordan, D.; Koster, U.; Marta, M.; Muller, S.E.; Szucs, T.; Tain, J.L.; Zuber, K.
Title (down) Neutron flux and spectrum in the Dresden Felsenkeller underground facility studied by moderated He-3 counters Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 12 Pages 123027 - 15pp
Keywords
Abstract Ambient neutrons may cause significant background for underground experiments. Therefore, it is necessary to investigate their flux and energy spectrum in order to devise a proper shielding. Here, two sets of altogether ten moderated He-3 neutron counters are used for a detailed study of the ambient neutron background in tunnel IV of the Felsenkeller facility, underground below 45 m of rock in Dresden/Germany. One of the moderators is lined with lead and thus sensitive to neutrons of energies higher than 10 MeV. For each He-3 counter moderator assembly, the energy-dependent neutron sensitivity was calculated with the FLUKA code. The count rates of the ten detectors were then fitted with the MAXED and GRAVEL packages. As a result, both the neutron energy spectrum from 10(-9) to 300 MeV and the flux integrated over the same energy range were determined experimentally. The data show that at a given depth, both the flux and the spectrum vary significantly depending on local conditions. Energy-integrated fluxes of (0.61 +/- 0.05), (1.96 +/- 0.15), and (4.6 +/- 0.4) x 10(-4) cm(-2) s(-1), respectively, are measured for three sites within Felsenkeller tunnel IV which have similar muon flux but different shielding wall configurations. The integrated neutron flux data and the obtained spectra for the three sites are matched reasonably well by FLUKA Monte Carlo calculations that are based on the known muon flux and composition of the measurement room walls.
Address [Grieger, M.; Hensel, T.; Bemmerer, D.; Mueller, S. E.; Szuecs, T.] Helmholtz Zentrum Dresden Rossendorf HZDR, D-01328 Dresden, Germany, Email: d.bemmerer@hzdr.de
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000542517900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4442
Permanent link to this record
 

 
Author n_TOF Collaboration (Lederer, C. et al); Giubrone, G.; Domingo-Pardo, C.; Tain, J.L.
Title (down) Neutron Capture Reactions on Fe and Ni Isotopes for the Astrophysical s-process Type Journal Article
Year 2014 Publication Nuclear Data Sheets Abbreviated Journal Nucl. Data Sheets
Volume 120 Issue Pages 201-204
Keywords
Abstract Neutron capture cross sections in the keV neutron energy region are the key nuclear physics input to study the astrophysical slow neutron capture process. In the past years, a series of neutron capture cross section measurements has been performed at the neutron time-of-flight facility n_TOF at CERN focussing on the Fe/Ni mass region. Recent results and future developments in the neutron time-of-flight technique are discussed.
Address [Lederer, C.; Pavlik, A.; Wallner, A.] Univ Vienna, Fac Phys, A-1090 Vienna, Austria, Email: claudia.lederer@ed.ac.uk
Corporate Author Thesis
Publisher Academic Press Inc Elsevier Science Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0090-3752 ISBN Medium
Area Expedition Conference
Notes WOS:000339860100056 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1875
Permanent link to this record
 

 
Author n_TOF Collaboration (Guerrero, C. et al); Domingo-Pardo, C.; Tain, J.L.
Title (down) Neutron Capture on the s-Process Branching Point Tm-171 via Time-of-Flight and Activation Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 125 Issue 14 Pages 142701 - 8pp
Keywords
Abstract The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable Tm-171 (t(1/2) = 1.92 yr) is part of the branching around mass A similar to 170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of Tm-171 at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (nTOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time -of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384 (40) mb, with which the estimation from the nTOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KAlloNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A similar to 170 branching, namely, the Yb-171 abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.
Address [Guerrero, C.; Lerendegui-Marco, J.; Quesada, J. M.; Cortes-Giraldo, M. A.; Millan-Callado, M. A.; Praena, J.; Rodriguez-Gonzalez, T.; Sabate-Gilarte, M.] Univ Seville, Seville, Spain, Email: cguerrero4@us.es
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000574781200004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4551
Permanent link to this record
 

 
Author n_TOF Collaboration (Tagliente, G. et al.); Domingo-Pardo, C.; Tain, J.L.
Title (down) Neutron capture on (94)Zr: Resonance parameters and Maxwellian-averaged cross sections Type Journal Article
Year 2011 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 84 Issue 1 Pages 015801 - 9pp
Keywords
Abstract The neutron capture cross sections of the Zr isotopes play an important role in nucleosynthesis studies. The s-process reaction flow between the Fe seed and the heavier isotopes passes through the neutron magic nucleus (90)Zr and through (91,92,93,94)Zr, but only part of the flow extends to (96)Zr because of the branching point at (95)Zr. Apart from their effect on the s-process flow, the comparably small isotopic (n, gamma) cross sections make Zr also an interesting structural material for nuclear reactors. The (94)Zr (n, gamma) cross section has been measured with high resolution at the spallation neutron source n_TOF at CERN and resonance parameters are reported up to 60 keV neutron energy.
Address [Tagliente, G; Colonna, N; Marrone, S; Terlizzi, R] Ist Nazl Fis Nucl, I-70126 Bari, Italy, Email: giuseppe.tagliente@ba.infn.it
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000292767200010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 687
Permanent link to this record
 

 
Author n_TOF Collaboration; Gunsing, F.; Berthoumieux, E.; Borella, A.; Belgya, T.; Szentmiklosi, L.; Schillebeeckx, P.; Drohe, J.C.; Wynants, R.; Colonna, N.; Marrone, S.; Tagliente, G.; Terlizzi, R.; Domingo-Pardo, C.; Tain, J.L.; Martinez, T.; Massimi, C.; Mastinu, P.M.; Milazzo, P.M.
Title (down) Neutron Capture on (209)Bi: Determination of the Production Ratio of (210m)Bi/(210g)Bi Type Journal Article
Year 2011 Publication Journal of the Korean Physical Society Abbreviated Journal J. Korean Phys. Soc.
Volume 59 Issue 2 Pages 1670-1675
Keywords ND2010; Nuclear data; Neutron capture; Branching ratio; Statistical decay; (209)Bi; (210)Bi; (210)Po
Abstract Neutron capture on (209)Bi produces either an isomeric state (210m)Bi with a half life of 3 x 106 years, or the ground state (210g)Bi which decays with a half life of 5 days to the alpha emitter (210)Po. Therefore the neutron capture cross section ratio (209)Bi(n,gamma)(210m)Bi/(210g)Bi plays an important role in predicting the short- and long-term radio-toxicity produced by (209)Bi under neutron irradiation. This ratio is dependent on the neutron energy. We have measured this ratio for cold neutrons at the cold neutron beam facility of the Budapest Neutron Centre by observing the population of the ground-and the metastable state using high resolution gamma-ray spectroscopy. The same technique has been used at the pulsed white neutron source GELINA of the IRMM, Geel in combination with the neutron time-of-flight technique. Results for the neutron-energy dependent branching ratio will be presented. In addition we performed simulations using a statistical decay code.
Address [Gunsing, F; Berthoumieux, E; Borella, A] CEA Saclay, IRFU, SPhN, F-91911 Gif Sur Yvette, France, Email: gunsing@cea.fr
Corporate Author Thesis
Publisher Korean Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0374-4884 ISBN Medium
Area Expedition Conference
Notes WOS:000294080700051 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 736
Permanent link to this record