Measurement of theSm151(n,γ) cross section from 0.6 eV to 1 MeV via the neutron time-of-flight technique at the CERN n_TOF

Abstract

The 151 Sm(n, γ ) cross section was measured with the time-of-flight technique from 0.6 eV up to 1 MeV relative to the Au standard with an overall uncertainty of typically 6%. Neutrons were produced by spallation at the innovative n TOF facility at CERN; the γ rays from capture events were detected with organic C 6 D 6 scintillators. Experimental setup and data analysis procedures are described with emphasis on the corrections for detection efficiency, background subtraction, and neutron flux determination. At low energies, resonances could be resolved up to about 1 keV, yielding a resonance integral of 3575 ± 210 b, an average s-wave resonance spacing of D 0 = 1.49 ± 0.07 eV, and a neutron strength function of S 0 = (3.87 ± 0.33) × 10 −4 . Maxwellian-averaged capture cross sections are reported for thermal energies between 5 and 100 keV. These results are of relevance for nuclear structure studies, nuclear astrophysics, and nuclear technology. The new value of the Maxwellian-averaged cross section at kT = 30 keV is 3.08 ± 0.15 b, considerably larger than previous theoretical estimates, and provides better constraints for the thermodynamic conditions during the occurrence of the slow neutron capture process in low-mass stars during their asymptotic giant branch phase.

Photoneutron cross sections for neodymium isotopes: Toward a unified understanding of(γ,n)and(n,γ)reactions in the rare earth region

“…While some of radioactive nuclei with half-lives (T 1/2 ) of the order of years have become objectives for direct measurements, for example, 151 Sm (T 1/2 = 90 yr) [5,6] and 63 Ni (T 1/2 = 100 yr) [7] at CERN/n-TOF, 147 Pm (T 1/2 = 2.62 yr) at Karlsruhe [8], 244 Cm (T 1/2 = 18.1 yr) [9] at J-Parc (Tokai), and 173 Lu (T 1/2 = 1.73 yr) [10] in progress at LANSCE (Los Alamos), those with T 1/2 of the order of days and shorter are far beyond the experimental scope at present.…”

Measurement of Neutron Capture Cross Section Ratios of 244Cm Resonances Using NNRI

“…4 The neutron-nucleus reaction instrument (NNRI) was installed at the J-PARC MLF Beam Line No. 4 (BL04), and preliminary measurements have been performed during the commissioning phase since June 2009.…”

Present status and future programs of the n_TOF experiment

“…, M. Calviani 1) , V. Vlachoudis 1) , C. Weiß 2) , S. Andriamonje 1) , J. Andrzejewski 3) , L. Audouin 4) , V. Avrigeanu 5) , M. Barbagallo 6) , V. Bécares 7) , F. Bečvář 8) , F. Belloni 9) , E. Berthoumieux 1,9) , J. Billowes 10) , V. Boccone 1) , M. Brugger 1) , F. Calviño 11) , D. Cano-Ott 7) , C. Carrapiço 12) , F. Cerutti 1) , M. Chin 1) , N. Colonna 6) , G. Cortés 11) , M.A. Cortés-Giraldo 13) , M. Diakaki 14) , I. Dillmann 15) , C. Domingo-Pardo 16) , I. Duran 17) , N. Dzysiuk 18) , C. Eleftheriadis 19) , M. Fernández-Ordóñez 7) , A. Ferrari 1) , K. Fraval 9) , S. Ganesan 20) , G. Giubrone 21) , M.B.…”

“…Cortés-Giraldo 13) , M. Diakaki 14) , I. Dillmann 15) , C. Domingo-Pardo 16) , I. Duran 17) , N. Dzysiuk 18) , C. Eleftheriadis 19) , M. Fernández-Ordóñez 7) , A. Ferrari 1) , K. Fraval 9) , S. Ganesan 20) , G. Giubrone 21) , M.B. Gómez-Hornillos 11) , I.F. Gonçalves 12) , E. González-Romero 7) , F. Gramegna 18) , E. Griesmayer 2) , C. Guerrero 1) , F. Gunsing 9) , M. Heil 16) , D.G.…”

“…Mastinu 18) , M. Mastromarco 6) , M. Meaze 6) , E. Mendoza 7) , A. Mengoni 27) , P.M. Milazzo 28) , M. Mirea 5) , C. Paradela 17) , A. Pavlik 25) , J. Perkowski 3) , J. Praena 13) , J.M. Quesada 13) , T. Rauscher 29) , R. Reifarth 16) , A. Riego 11) , F. Roman 1,5) , C. Rubbia 1,30) , R. Sarmento 12) , G. Tagliente 6) , J.L. Tain 21) , D. Tarrìo 17) , L. Tassan-Got 4) , A. Tsinganis 1) , S. Valenta 8) , G. Vannini 26) , V. Variale 6) , P. Vaz 12) , A. Ventura 27) , M.J. Vermeulen 22) , R. Versaci 1) , R. Vlastou 14) , A. Wallner 25) , T. Ware 10) , T.J.…”