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Author Krzysiek, M. et al; Gadea, A.; Huyuk, T.; Barrientos, D.
Title Study of the soft dipole modes in Ce-140 via inelastic scattering of O-17 Type Journal Article
Year 2014 Publication Physica Scripta Abbreviated Journal Phys. Scr.
Volume 89 Issue 5 Pages 054016 - 6pp
Keywords pygmy dipole resonances; inelastic scattering; AGATA detector; gamma spectroscopy
Abstract The main aim of this study was a deeper understanding of the nuclear structure properties of the soft dipole modes in Ce-140, excited via inelastic scattering of weakly bound O-17 projectiles. An important aim was to investigate the 'splitting' of the PDR into two parts: a low-energy isoscalar component dominated by neutron-skin oscillations and a higher-energy component lying on the tail of the giant dipole resonance of a rather isovector character. This was already observed for this nucleus, investigated in (alpha, alpha') and (gamma,gamma') experiments. The experiment was performed at Laboratori Nazionali di Legnaro, Italy. Inelastic scattering of O-17 ion beam at 20 MeV A(-1) was used to excite the resonance modes in the Ce-140 target. Gamma-rays were registered by five triple clusters of AGATA-Demonstrator and nine large volume scintillators (LaBr3). The scattered O-17 ions were identified by two Delta E – E Si telescopes of the TRACE array mounted inside the scattering chamber. The telescopes consisted of two segmented Si-pad detectors, each of 60 pixels. Very preliminary data have shown a strong domination of the E1 transitions in the 'pygmy' region with a character more similar to the one obtained in alpha scattering experiment.
Address (up) [Krzysiek, M.; Kmiecik, M.; Maj, A.; Bednarczyk, P.; Ciemala, M.; Fornal, B.; Grebosz, J.; Mazurek, K.; Meczynski, W.; Zieblinski, M.] Polish Acad Sci, H Niewodniczanski Inst Nucl Phys, Krakow, Poland, Email: mateusz.krzysiek@ifj.edu.pl
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-8949 ISBN Medium
Area Expedition Conference
Notes WOS:000335785300016 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1790
Permanent link to this record
 
 
Author DELPHI Collaboration (Abdallah, J. et al); Costa, M.J.; Ferrer, A.; Fuster, J.; Garcia, C.; Oyanguren, A.; Perepelitsa, V.; Salt, J.; Tortosa, P.
Title Measurement of the electron structure function F-2(e) at LEP energies Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 737 Issue Pages 39-47
Keywords
Abstract The hadronic part of the electron structure function F-2(e) has been measured for the first time, using e(+)e(-) data collected by the DELPHI experiment at LEP, at centre-of-mass energies of root s = 91.2-209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F-2(e) data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F-2(gamma) analyses and help in refining existing parameterizations.
Address (up) [Lamsa, J.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA
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 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000342757700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1965
Permanent link to this record
 
 
Author Landete, A.; Navarro-Salas, J.; Torrenti, F.
Title Adiabatic regularization and particle creation for spin one-half fields Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 89 Issue 4 Pages 044030 - 13pp
Keywords
Abstract The extension of the adiabatic regularization method to spin-1/2 fields requires a self-consistent adiabatic expansion of the field modes. We provide here the details of such expansion, which differs from the WKB ansatz that works well for scalars, to firmly establish the generalization of the adiabatic renormalization scheme to spin-1/2 fields. We focus on the computation of particle production in de Sitter spacetime and obtain an analytic expression of the renormalized stress-energy tensor for Dirac fermions.
Address (up) [Landete, Aitor] Univ Valencia, Fac Fis, Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, E-46100 Valencia, Spain
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:000332170300012 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1710
Permanent link to this record
 
 
Author Langer, C. et al; Domingo-Pardo, C.
Title Determining the rp-Process Flow through Ni-56: Resonances in Cu-57(p,gamma)Zn-58 Identified with GRETINA Type Journal Article
Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 113 Issue 3 Pages 032502 - 5pp
Keywords
Abstract An approach is presented to experimentally constrain previously unreachable (p,gamma) reaction rates on nuclei far from stability in the astrophysical rp process. Energies of all critical resonances in the Cu-57(p,gamma)Zn-58 reaction are deduced by populating states in Zn-58 with a (d, n) reaction in inverse kinematics at 75 MeV/u, and detecting.-ray-recoil coincidences with the state-of-the-art gamma-ray tracking array GRETINA and the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The results reduce the uncertainty in the Cu-57(p,gamma) reaction rate by several orders of magnitude. The effective lifetime of Ni-56, an important waiting point in the rp process in x-ray bursts, can now be determined entirely from experimentally constrained reaction rates.
Address (up) [Langer, C.; Montes, F.; Bazin, D.; Brown, B. A.; Browne, J.; Cyburt, R. H.; Gade, A.; Keek, L.; Kontos, A.; Lemasson, A.; Lunderberg, E.; Meisel, Z.; Noji, S.; Nunes, F. M.; Perdikakis, G.; Pereira, J.; Quinn, S. J.; Recchia, F.; Schatz, H.; Scott, M.; Simon, A.; Spyrou, A.; Stevens, J.; Stroberg, S. R.; Weisshaar, D.; Wheeler, J.; Wimmer, K.; Zegers, R. G. T.] Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA, Email: langer@nscl.msu.edu
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:000344180500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1991
Permanent link to this record
 
 
Author Lattanzi, M.; Lineros, R.A.; Taoso, M.
Title Connecting neutrino physics with dark matter Type Journal Article
Year 2014 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 16 Issue Pages 125012 - 19pp
Keywords neutrinos; dark matter; flavour; majoron; sterile neutrinos
Abstract The origin of neutrino masses and the nature of dark matter are two in most pressing open questions in modern astro-particle physics. We consider here the possibility that these two problems are related, and review some theoretical scenarios which offer common solutions. A simple possibility is that the dark matter particle emerges in minimal realizations of the seesaw mechanism, as in the majoron and sterile neutrino scenarios. We present the theoretical motivation for both models and discuss their phenomenology, confronting the predictions of these scenarios with cosmological and astrophysical observations. Finally, we discuss the possibility that the stability of dark matter originates from a flavor symmetry of the leptonic sector. We review a proposal based on an A(4) flavor symmetry.
Address (up) [Lattanzi, Massimiliano] Univ Ferrara, Dipartimento Fis & Sci Terra, I-44122 Ferrara, Italy, Email: lattanzi@fe.infn.it;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000346823200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2062
Permanent link to this record
 
 
Author n_TOF Collaboration (Lederer, C. et al); Giubrone, G.; Domingo-Pardo, C.; Tain, J.L.
Title 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 (up) [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 (Lederer, C. et al.); Giubrone, G.; Tain, J.L.
Title Ni-62(n,gamma) and Ni-63(n,gamma) cross sections measured at the n_TOF facility at CERN Type Journal Article
Year 2014 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 89 Issue 2 Pages 025810 - 11pp
Keywords
Abstract The cross section of the Ni-62(n,gamma) reaction was measured with the time-of-flight technique at the neutron time-of-flight facility nTOF at CERN. Capture kernels of 42 resonances were analyzed up to 200 keV neutron energy and Maxwellian averaged cross sections (MACS) from kT = 5-100 keV were calculated. With a total uncertainty of 4.5%, the stellar cross section is in excellent agreement with the the KADoNiS compilation at kT = 30 keV, while being systematically lower up to a factor of 1.6 at higher stellar temperatures. The cross section of the Ni-63(n,gamma) reaction was measured for the first time at nTOF. We determined unresolved cross sections from 10 to 270 keV with a systematic uncertainty of 17%. These results provide fundamental constraints on s-process production of heavier species, especially the production of Cu in massive stars, which serve as the dominant source of Cu in the solar system.
Address (up) [Lederer, C.; Wallner, A.; Pavlik, A.] Univ Vienna, Fac Phys, A-1010 Vienna, Austria, Email: claudia.lederer@ph.ed.uk
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:000332175500012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1717
Permanent link to this record
 
 
Author Ledwig, T.; Nieves, J.; Pich, A.; Ruiz Arriola, E.; Ruiz de Elvira, J.
Title Large-N-c naturalness in coupled-channel meson-meson scattering Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 90 Issue 11 Pages 114020 - 17pp
Keywords
Abstract The analysis of hadronic interactions with effective field theory techniques is complicated by the appearance of a large number of low-energy constants, which are usually fitted to data. On the other hand, the large-N-c limit helps to impose natural short-distance constraints on these low-energy constants, providing a parameter reduction. A Bayesian interpretation of the expected 1/N-c accuracy allows for an easy and efficient implementation of these constraints, using an augmented chi(2). We apply this approach to the analysis of meson-meson scattering, in conjunction with chiral perturbation theory to one loop and coupled-channel unitarity, and show that it helps to largely reduce the many existing ambiguities and simultaneously provide an acceptable description of the available phase shifts.
Address (up) [Ledwig, T.; Nieves, J.; Pich, A.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Valencia 46071, Spain
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:000348730800008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2100
Permanent link to this record
 
 
Author Ledwig, T.; Martin Camalich, J.; Geng, L.S.; Vicente Vacas, M.J.
Title Octet-baryon axial-vector charges and SU(3)-breaking effects in the semileptonic hyperon decays Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 90 Issue 5 Pages 054502 - 16pp
Keywords
Abstract The octet-baryon axial-vector charges and the g(1)/f(1) ratios measured in the semileptonic hyperon decays are studied up to O(p(3)) using the covariant baryon chiral perturbation theory with explicit decuplet contributions. We clarify the role of different low-energy constants and find a good convergence for the chiral expansion of the axial-vector charges of the baryon octet, g(1)(0), with O(p(3)) corrections typically around 20% of the leading ones. This is a consequence of strong cancellations between different next-to-leading- order terms. We show that considering only nonanalytic terms is not enough and that analytic terms appearing at the same chiral order play an important role in this description. The same effects still hold for the chiral extrapolation of the axial-vector charges and result in a rather mild quark-mass dependence. As a result, we report a determination of the leading-order chiral couplings, D = 0.623(61)(17) and F = 0.441(47)(2), as obtained from a completely consistent chiral analysis up to O(p(3)). Furthermore, we note that the appearance of an unknown low-energy constant precludes the extraction of the proton octet charge from semileptonic decay data alone, which is relevant for an analysis of the composition of the proton spin.
Address (up) [Ledwig, T.; Vicente Vacas, M. J.] Univ Valencia, CSIC, Inst Invest Paterna, Dept Fis Teor, Paterna 46980, Spain, Email: ledwig@ific.uv.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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000341264600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1899
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Dalitz plot analysis of eta(c) -> K+K-eta and eta(c) -> K+K-pi(0) in two-photon interactions Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 89 Issue 11 Pages 112004 - 16pp
Keywords
Abstract We study the processes gamma gamma -> K+K-eta and gamma gamma -> K+K-pi(0) using a data sample of 519 fb(-1) recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e(+)e(-) collider at center-of-mass energies at and near the Upsilon(nS) (n = 2, 3, 4) resonances. We observe eta(c) -> K+K-pi(0) and eta(c) -> K+K-eta decays, measure their relative branching fraction, and perform a Dalitz plot analysis for each decay. We observe the K*(0)(1430) -> K eta decay and measure its branching fraction relative to the K pi decay mode to be R(K*(0)(1430)) = B(K*(0)(1430)-> K eta)/B(K*(0)(1430)-> K pi) = 0.092 +/- 0.025(- 0.025)(+0.010). The eta(c) -> K+K-eta and K*(0)(1430) -> K eta results correspond to the first observations of these channels. The data also show evidence for eta(c)(2S) -> K+K-pi(0) and first evidence for eta(c)(2S) -> K+K-eta.
Address (up) [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, Lab Annecy le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France
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:000337731800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1826
Permanent link to this record