toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Molina, F.; Aguilera, P.; Romero-Barrientos, J.; Arellano, H.F.; Agramunt, J.; Medel, J.; Morales, J.R.; Zambra, M. doi  openurl
  Title Energy distribution of the neutron flux measurements at the Chilean Reactor RECH-1 using multi-foil neutron activation and the Expectation Maximization unfolding algorithm Type Journal Article
  Year 2017 Publication Applied Radiation and Isotopes Abbreviated Journal Appl. Radiat. Isot.  
  Volume 129 Issue (down) Pages 28-34  
  Keywords  
  Abstract We present a methodology to obtain the energy distribution of the neutron flux of an experimental nuclear reactor, using multi-foil activation measurements and the Expectation Maximization unfolding algorithm, which is presented as an alternative to well known unfolding methods such as GRAVEL. Self-shielding flux corrections for energy bin groups were obtained using MCNP6 Monte Carlo simulations. We have made studies at the at the Dry Tube of RECH-1 obtaining fluxes of 1.5(4) x 10(13) cm(-2) s(-1) for the thermal neutron energy region, 1.9(5) x 10(12) cm(-2) s(-1) for the epithermal neutron energy region, and 4.3(11) x 10(11) cm(-2) s(-1) for the fast neutron energy region.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0969-8043 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000413058200005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3326  
Permanent link to this record
 

 
Author Luo, X.L. et al; Agramunt, J.; Egea, F.J.; Gadea, A.; Huyuk, T. doi  openurl
  Title Pulse pile-up identification and reconstruction for liquid scintillator based neutron detectors Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 897 Issue (down) Pages 59-65  
  Keywords Pile-up; Digital; First-order derivative; Neutron-gamma discrimination; Liquid scintillator  
  Abstract The issue of pulse pile-up is frequently encountered in nuclear experiments involving high counting rates, which will distort the pulse shapes and the energy spectra. A digital method of off-line processing of pile-up pulses is presented. The pile-up pulses were firstly identified by detecting the downward-going zero-crossings in the first-order derivative of the original signal, and then the constituent pulses were reconstructed based on comparing the pile-up pulse with four models that are generated by combining pairs of neutron and.. standard pulses together with a controllable time interval. The accuracy of this method in resolving the pile-up events was investigated as a function of the time interval between two pulses constituting a pile-up event. The obtained results show that the method is capable of disentangling two pulses with a time interval among them down to 20 ns, as well as classifying them as neutrons or gamma rays. Furthermore, the error of reconstructing pile-up pulses could be kept below 6% when successive peaks were separated by more than 50 ns. By applying the method in a high counting rate of pile-up events measurement of the NEutron Detector Array (NEDA), it was empirically found that this method can reconstruct the pile-up pulses and perform neutron-gamma discrimination quite accurately. It can also significantly correct the distorted pulse height spectrum due to pile-up events.  
  Address [Luo, X. L.] Acad Mil Med Sci, Natl Innovat Inst Def Technol, Beijing 100010, Peoples R China, Email: delongtmac@163.com  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000433206800010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3591  
Permanent link to this record
 

 
Author Rasco, B.C.; Brewer, N.T.; Yokoyama, R.; Grzywacz, R.; Rykaczewski, K.P.; Tolosa-Delgado, A.; Agramunt, J.; Tain, J.L.; Algora, A.; Hall, O.; Griffin, C.; Davinson, T.; Phong, V.H.; Liu, J.; Nishimura, S.; Kiss, G.G.; Nepal, N.; Estrade, A. url  doi
openurl 
  Title The ORNL analysis technique for extracting beta-delayed multi-neutron branching ratios with BRIKEN Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 911 Issue (down) Pages 79-86  
  Keywords Neutron detectors; Multi-neutron emission data analysis  
  Abstract Many choices are available in order to evaluate large radioactive decay networks. There are many parameters that influence the calculated beta-decay delayed single and multi-neutron emission branching fractions. We describe assumptions about the decay model, background, and other parameters and their influence on beta-decay delayed multi-neutron emission analysis. An analysis technique, the ORNL BRIKEN analysis procedure, for determining beta-delayed multi-neutron branching ratios in beta-neutron precursors produced by means of heavy-ion fragmentation is presented. The technique is based on estimating the initial activities of zero, one, and two neutrons occurring in coincidence with an ion-implant and beta trigger. The technique allows one to extract beta-delayed multi-neutron decay branching ratios measured with the He-3 BRIKEN neutron counter. As an example, two analyses of the beta-neutron emitter Cu-77 based on different a priori assumptions are presented along with comparisons to literature values.  
  Address [Rasco, B. C.; Brewer, N. T.; Rykaczewski, K. P.] Oak Ridge Natl Lab, Phys Div, Oak Ridge, TN 37831 USA, Email: brasco@utk.edu  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000450880200013 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3813  
Permanent link to this record
 

 
Author Guadilla, V. et al; Tain, J.L.; Algora, A.; Agramunt, J.; Gelletly, W.; Jordan, D.; Monserrate, M.; Montaner-Piza, A.; Orrigo, S.E.A.; Rubio, B.; Valencia, E. url  doi
openurl 
  Title Characterization and performance of the DTAS detector Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 910 Issue (down) Pages 79-89  
  Keywords beta decay; Total absorption gamma-ray spectrometer; Exotic nuclei; NaI(Tl) detector; Non-proportional scintillation light yield; Monte Carlo simulations  
  Abstract DTAS is a segmented total absorption y-ray spectrometer developed for the DESPEC experiment at FAIR. It is composed of up to eighteen NaI(Tl) crystals. In this work we study the performance of this detector with laboratory sources and also under real experimental conditions. We present a procedure to reconstruct offline the sum of the energy deposited in all the crystals of the spectrometer, which is complicated by the effect of NaI(Tl) light-yield non-proportionality. The use of a system to correct for time variations of the gain in individual detector modules, based on a light pulse generator, is demonstrated. We describe also an event-based method to evaluate the summing-pileup electronic distortion in segmented spectrometers. All of this allows a careful characterization of the detector with Monte Carlo simulations that is needed to calculate the response function for the analysis of total absorption gamma-ray spectroscopy data. Special attention was paid to the interaction of neutrons with the spectrometer, since they are a source of contamination in studies of beta-delayed neutron emitting nuclei.  
  Address [Guadilla, V; Tain, J. L.; Algora, A.; Agramunt, J.; Gelletly, W.; Jordan, D.; Monserrate, M.; Montaner-Piza, A.; Orrigo, S. E. A.; Rubio, B.; Valencia, E.] CSIC Univ Valencia, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: guadilla@ific.uv.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000453652500010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3847  
Permanent link to this record
 

 
Author Soderstrom, P.A. et al; Agramunt, J.; Egea, J.; Gadea, A.; Huyuk, T. doi  openurl
  Title Neutron detection and gamma-ray suppression using artificial neural networks with the liquid scintillators BC-501A and BC-537 Type Journal Article
  Year 2019 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 916 Issue (down) Pages 238-245  
  Keywords BC-501A; BC-537; Digital pulse-shape discrimination; Fast-neutron detection; Liquid scintillator; Neural networks  
  Abstract In this work we present a comparison between the two liquid scintillators BC-501A and BC-537 in terms of their performance regarding the pulse-shape discrimination between neutrons and gamma rays. Special emphasis is put on the application of artificial neural networks. The results show a systematically higher gamma-ray rejection ratio for BC-501A compared to BC-537 applying the commonly used charge comparison method. Using the artificial neural network approach the discrimination quality was improved to more than 95% rejection efficiency of gamma rays over the energy range 150 to 1000 keV for both BC-501A and BC-537. However, due to the larger light output of BC-501A compared to BC-537, neutrons could be identified in BC-501A using artificial neural networks down to a recoil proton energy of 800 keV compared to a recoil deuteron energy of 1200 keV for BC-537. We conclude that using artificial neural networks it is possible to obtain the same gamma-ray rejection quality from both BC-501A and BC-537 for neutrons above a low-energy threshold. This threshold is, however, lower for BC-501A, which is important for nuclear structure spectroscopy experiments of rare reaction channels where low-energy interactions dominates.  
  Address [Soderstrom, P-A] ELI NP, Bucharest 077125, Romania, Email: par.anders@eli-np.ro  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000455016800033 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3869  
Permanent link to this record
 

 
Author BRIKEN Collaboration (Tolosa-Delgado, A. et al); Agramunt, J.; Tain, J.L.; Algora, A.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B. url  doi
openurl 
  Title Commissioning of the BRIKEN detector for the measurement of very exotic beta-delayed neutron emitters Type Journal Article
  Year 2019 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 925 Issue (down) Pages 133-147  
  Keywords Beta-delayed neutrons; Neutron and beta counters; Analysis methodology; Background correction  
  Abstract A new detection system has been installed at the RIKEN Nishina Center (Japan) to investigate decay properties of very neutron-rich nuclei. The setup consists of three main parts: a moderated neutron counter, a detection system sensitive to the implantation and decay of radioactive ions, and gamma-ray detectors. We describe here the setup, the commissioning experiment and some selected results demonstrating its performance for the measurement of half-lives and beta-delayed neutron emission probabilities. The methodology followed in the analysis of the data is described in detail. Particular emphasis is placed on the correction of the accidental neutron background.  
  Address [Tolosa-Delgado, A.; Agramunt, J.; Tain, J. L.; Algora, A.; Domingo-Pardo, C.; Morales, A., I; Rubio, B.] CSIC, Inst Fis Corpuscular, E-46980 Paterna, Spain, Email: tain@ific.uv.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000460539400018 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3939  
Permanent link to this record
 

 
Author Yokoyama, R.; Singh, M.; Grzywacz, R.; Keeler, A.; King, T.T.; Agramunt, J.; Brewer, N.T.; Go, S.; Heideman, J.; Liu, J.; Nishimura, S.; Parkhurst, P.; Phong, V.H.; Rajabali, M.M.; Rasco, B.C.; Rykaczewski, K.P.; Stracener, D.W.; Tain, J.L.; Tolosa-Delgado, A.; Vaigneur, K.; Wolinska-Cichocka, M. url  doi
openurl 
  Title Segmented YSO scintillation detectors as a new beta-implant detection tool for decay spectroscopy in fragmentation facilities Type Journal Article
  Year 2019 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 937 Issue (down) Pages 93-97  
  Keywords Beta-decay; Implant-beta detector; Radioactive isotopes; Fragmentation  
  Abstract A newly developed segmented YSO scintillator detector was implemented for the first time at the RI-beam Factory at RIKEN Nishina Center as an implantation-decay counter. The results from the experiment demonstrate that the detector is a viable alternative to conventional silicon-strip detectors with its good timing resolution and high detection efficiency for beta particles. A Position-Sensitive Photo-Multiplier Tube (PSPMT) is coupled with a 48 x 48 segmented YSO crystal. To demonstrate its capabilities, a known short-lived isomer in Ni-76 and the beta decay of Co-74 were measured by implanting those ions into the YSO detector. The half-lives and gamma-rays observed in this work are consistent with the known values. The beta-ray detection efficiency is more than 80 % for the decay of Co-74.  
  Address [Yokoyama, R.; Singh, M.; Grzywacz, R.; Keeler, A.; King, T. T.; Brewer, N. T.; Heideman, J.; Rasco, B. C.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA, Email: ryokoyam@utk.edu  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000471139300010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4054  
Permanent link to this record
 

 
Author Hall, O. et al; Agramunt, J.; Algora, A.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B.; Tain, J.L.; Tolosa-Delgado, A. doi  openurl
  Title beta-delayed neutron emission of r-process nuclei at the N=82 shell closure Type Journal Article
  Year 2021 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 816 Issue (down) Pages 136266 - 7pp  
  Keywords beta-delayed neutron emission; r-processimportant  
  Abstract Theoretical models of beta-delayed neutron emission are used as crucial inputs in r-process calculations. Benchmarking the predictions of these models is a challenge due to a lack of currently available experimental data. In this work the beta-delayed neutron emission probabilities of 33 nuclides in the important mass regions south and south-west of Sn-132 are presented, 16 for the first time. The measurements were performed at RIKEN using the Advanced Implantation Detector Array (AIDA) and the BRIKEN neutron detector array. The P-1n values presented constrain the predictions of theoretical models in the region, affecting the final abundance distribution of the second r-process peak at A approximate to 130.  
  Address [Hall, O.; Davinson, T.; Bruno, C. G.; Griffin, C. J.; Kahl, D.] Univ Edinburgh, Sch Phys & Astron, Edinburgh EH9 3FD, Midlothian, Scotland, Email: oscar.hall@ed.ac.uk  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000647421500016 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4819  
Permanent link to this record
 

 
Author Algora, A.; Ganioglu, E.; Sarriguren, P.; Guadilla, V.; Fraile, L.M.; Nacher, E.; Rubio, B.; Tain, J.L.; Agramunt, J.; Gelletly, W.; Briz, J.A.; Cakirli, R.B.; Fallot, M.; Jordan, D.; Halasz, Z.; Kuti, I.; Montaner, A.; Onillon, A.; Orrigo, S.E.A.; Cerdan, A.P.; Rice, S.; Vedia, V.; Valencia, E. url  doi
openurl 
  Title Total absorption gamma-ray spectroscopy study of the beta-decay of Hg-186 Type Journal Article
  Year 2021 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 819 Issue (down) Pages 136438 - 7pp  
  Keywords Betadecay; Totalabsorption spectroscopy; Shape coexistence  
  Abstract The Gamow-Teller strength distribution of the decay of Hg-186 into Au-186 has been determined for the first time using the total absorption gamma spectroscopy technique and has been compared with theoretical QRPA calculations using the SLy4 Skyrme force. The measured Gamow-Teller strength distribution and the half-life are described by mixing oblate and prolate configurations independently in the parent and daughter nuclei. In this theoretical framework the best description of the experimental beta strength is obtained with dominantly prolate components for both parent Hg-186 and daughter Au-186. The approach also allowed us to determine an upper limit of the oblate component in the parent state. The complexity of the analysis required the development of a new approach in the analysis of the X-ray gated total absorption spectrum.  
  Address [Algora, A.; Guadilla, V; Nacher, E.; Rubio, B.; Tain, J. L.; Agramunt, J.; Jordan, D.; Montaner, A.; Orrigo, S. E. A.; Cerdan, A. Perez; Valencia, E.] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain, Email: algora@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000679259200010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4923  
Permanent link to this record
 

 
Author Vitez-Sveiczer, A. et al; Algora, A.; Morales, A.I.; Rubio, B.; Agramunt, J.; Guadilla, V.; Montaner-Piza, A.; Orrigo, S.E.A. doi  openurl
  Title The beta-decay of Kr-70 into Br-70: Restoration of the pseudo-SU(4) symmetry Type Journal Article
  Year 2022 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 830 Issue (down) Pages 137123 - 8pp  
  Keywords Beta decay of Kr-70; pn pairing; GT strength distribution; Pseudo-SU(4) symmetry; QRPA calculations  
  Abstract The beta-decay of the even-even nucleus Kr-70 with Z=N+2, has been investigated at the Radioactive Ion Beam Factory (RIBF) of the RIKEN Nishina Center using the BigRIPS fragment separator, the ZeroDegree Spectrometer, the WAS3ABI implantation station and the EURICA HPGe cluster array. Fifteen gamma-rays associated with the beta-decay of( 70)Kr into Br-70 have been identified for the first time, defining ten populated states below E-exc=3300 keV. The half-life of Kr-70 was derived with increased precision and found to be t(1/2)=45.19 +/- 0.14 ms. The beta-delayed proton emission probability has also been determined as epsilon(p)=0.545(23)%. An increase in the beta-strength to the yrast 1(+) state in comparison with the heaviest Z=N+2 system studied so far (Ge-62 decay) is observed that may indicate increased np correlations in the T=0 channel. The beta-decay strength deduced from the results is interpreted in terms of the proton-neutron quasiparticle random-phase approximation (pnQRPA) and also with a schematic model that includes isoscalar and isovector pairing in addition to quadrupole deformation. The application of this last model indicates an approximate realization of pseudo-SU(4) symmetry in this system.  
  Address [Vitez-Sveiczer, A.; Algora, A.; Morales, A., I; Rubio, B.; Agramunt, J.; Guadilla, V; Montaner-Piza, A.; Orrigo, S. E. A.; Gelletly, W.] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain, Email: algora@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000832707200002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5316  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records:
ific federMinisterio de Ciencia e InnovaciĆ³nAgencia Estatal de Investigaciongva