| Records |
| Author |
Molina, F.; Aguilera, P.; Romero-Barrientos, J.; Arellano, H.F.; Agramunt, J.; Medel, J.; Morales, J.R.; Zambra, M. |
| 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 |
|
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 |
Nieves, J.; Sobczyk, J.E. |
| Title |
In medium dispersion relation effects in nuclear inclusive reactions at intermediate and low energies |
Type |
Journal Article |
| Year |
2017 |
Publication |
Annals of Physics |
Abbreviated Journal |
Ann. Phys. |
| Volume |
383 |
Issue |
|
Pages |
455-496 |
| Keywords |
Neutrino-nucleus scattering; Quasielastic mechanism; Spectral function; RPA; Muon capture; Radiative pion capture |
| Abstract |
In a well-established many-body framework, successful in modeling a great variety of nuclear processes, we analyze the role of the spectral functions (SFs) accounting for the modifications of the dispersion relation of nucleons embedded in a nuclear medium. We concentrate in processes mostly governed by one-body mechanisms, and study possible approximations to evaluate the particle hole propagator using SFs. We also investigate how to include together SFs and long-range RPA-correlation corrections in the evaluation of nuclear response functions, discussing the existing interplay between both type of nuclear effects. At low energy transfers (<= 50 MeV), we compare our predictions for inclusive muon and radiative pion captures in nuclei, and charge-current (CC) neutrino-nucleus cross sections with experimental results. We also present an analysis of intermediate energy quasi-elastic neutrino scattering for various targets and both neutrino and antineutrino CC driven processes. In all cases, we pay special attention to estimate the uncertainties affecting the theoretical predictions. In particular, we show that errors on the a,,sigma(mu)/sigma(e) ratio are much smaller than 5%, and also much smaller than the size of the SF+RPA nuclear corrections, which produce significant effects, not only in the individual cross sections, but also in their ratio for neutrino energies below 400 MeV. These latter nuclear corrections, beyond Pauli blocking, turn out to be thus essential to achieve a correct theoretical understanding of this ratio of cross sections of interest for appearance neutrino oscillation experiments. We also briefly compare our SF and RPA results to predictions obtained within other representative approaches. |
| Address |
[Nieves, Juan] Univ Valencia, CSIC,Ctr Mixto, Inst Invest Paterna, Inst Fis Corpuscular IFIC, Apartado 22085, E-46071 Valencia, Spain, Email: jmnieves@ific.uv.es |
| 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 |
0003-4916 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000407667300025 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3244 |
| Permanent link to this record |
| |
|
| |
| Author |
Wang, E.; Xie, J.J.; Liang, W.H.; Guo, F.K.; Oset, E. |
| Title |
Role of a triangle singularity in the gamma p -> K+Lambda (1405) reaction |
Type |
Journal Article |
| Year |
2017 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
95 |
Issue |
1 |
Pages |
015205 - 9pp |
| Keywords |
|
| Abstract |
We show the effects of a triangle singularity mechanism for the gamma p -> K+Lambda(1405) reaction. The mechanism has a N-* resonance around 2030 MeV, which decays into K*Sigma. The K-* decays to K+ pi, and the pi Sigma merge to form the Lambda (1405). This mechanism produces a peak around root s = 2110 MeV, and has its largest contribution around cos theta= 0. The addition of this mechanism to other conventional ones leads to a good reproduction of d sigma/dcos theta and the integrated cross section around this energy, providing a solution to a problem encountered in previous theoretical models. |
| Address |
[Wang, En] Zhengzhou Univ, Dept Phys, Zhengzhou 450001, Henan, Peoples R China |
| 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 |
2469-9985 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000392077300005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2917 |
| Permanent link to this record |
| |
|
| |
| Author |
Ilner, A.; Cabrera, D.; Markert, C.; Bratkovskaya, E. |
| Title |
K* vector meson resonance dynamics in heavy-ion collisions |
Type |
Journal Article |
| Year |
2017 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
95 |
Issue |
1 |
Pages |
014903 - 15pp |
| Keywords |
|
| Abstract |
We study the strange vector meson (K*, (K) over bar*) dynamics in relativistic heavy-ion collisions based on the microscopic parton-hadron-string dynamics (PHSD) transport approach which incorporates partonic and hadronic degrees of freedom, a phase transition from hadronic to partonic matter-quark-gluon-plasma (QGP)-and a dynamical hadronization of quarks and antiquarks as well as final hadronic interactions. We investigate the role of in-medium effects on the K*, (K) over bar* meson dynamics by employing Breit-Wigner spectral functions for the K* with self-energies obtained from a self-consistent coupled-channelG-matrix approach. Furthermore, we confront the PHSD calculations with experimental data for p + p, Cu + Cu, and Au + Au collisions at energies up to root s(NN) = 200 GeV. Our analysis shows that, at relativistic energies, most of the final K* (observed experimentally) are produced during the late hadronic phase, dominantly by the K + pi -> K* channel, such that the fraction of the K* from the QGP is small and can hardly be reconstructed from the final observables. The influence of the in-medium effects on the K* dynamics at energies typical of the BNL Relativistic Heavy Ion Collider is rather modest due to their dominant production at low baryon densities (but high meson densities); however, it increases with decreasing beam energy. Moreover, we find that the additional cut on the invariant-mass region of the K* further influences the shape and the height of the final spectra. This imposes severe constraints on the interpretation of the experimental results. |
| Address |
[Ilner, Andrej; Bratkovskaya, Elena] Johann Wolfgang Goethe Univ Frankfurt Main, Inst Theoret Phys, D-60438 Frankfurt, Germany, Email: ilner@fias.uni-frankfurt.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 |
2469-9985 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000391859800003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2918 |
| Permanent link to this record |
| |
|
| |
| Author |
Xie, J.J.; Liang, W.H.; Oset, E.; Moskal, P.; Skurzok, M.; Wilkin, C. |
| Title |
Determination of the eta He-3 threshold structure from the low energy pd -> eta He-3 reaction |
Type |
Journal Article |
| Year |
2017 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
95 |
Issue |
1 |
Pages |
015202 - 9pp |
| Keywords |
|
| Abstract |
We analyze the data on cross sections and asymmetries for the pd -> eta He-3 reaction close to threshold and look for bound states of the eta He-3 system. Rather than parameterizing the scattering matrix, as is usually done, we develop a framework in which the eta He-3 optical potential is the key ingredient, and its strength, together with some production parameters, are fitted to the available experimental data. The relationship of the scattering matrix to the optical potential is established using the Bethe-Salpeter equation and the eta He-3 loop function incorporates the range of the interaction given by the empirical He-3 density. We find a local Breit-Wigner form of the eta He-3 amplitude T below threshold with a clear peak in vertical bar T vertical bar(2), which corresponds to an eta He-3 binding of about 0.3 MeV and a width of about 3 MeV. By fitting the potential we can also evaluate the eta He-3 scattering length, including its sign, thus resolving the ambiguity in the former analyses. |
| Address |
[Xie, Ju-Jun; Oset, Eulogio] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China, Email: xiejujun@impcas.ac.cn; |
| 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 |
2469-9985 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000391859800004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2919 |
| Permanent link to this record |
