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Author Marchi, T. et al; Gadea, A.
Title Quadrupole Transition Strength in the Ni-74 Nucleus and Core Polarization Effects in the Neutron-Rich Ni Isotopes Type Journal Article
Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 113 Issue 18 Pages 182501 - 5pp
Keywords
Abstract The reduced transition probability B(E2;0(+) -> 2(+)) has been measured for the neutron-rich nucleus Ni-74 in an intermediate energy Coulomb excitation experiment performed at the National Superconducting Cyclotron Laboratory at Michigan State University. The obtained B(E2;0(+) -> 2(+)) = 642(-226)(+216) e(2) fm(4) value defines a trend which is unexpectedly small if referred to Ni-70 and to a previous indirect determination of the transition strength in Ni-74. This indicates a reduced polarization of the Z = 28 core by the valence neutrons. Calculations in the pfgd model space reproduce well the experimental result indicating that the B(E2) strength predominantly corresponds to neutron excitations. The ratio of the neutron and proton multipole matrix elements supports such an interpretation.
Address [Marchi, T.; de Angelis, G.; Valiente-Dobon, J. J.; Gottardo, A.; Gramegna, F.; Modamio, V.; Napoli, D. R.; Sahin, E.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy, Email: tommaso.marchi@lnl.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 0031-9007 ISBN Medium
Area Expedition Conference
Notes (down) WOS:000344117700003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1994
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Author Hernandez, P.; Kekic, M.; Lopez-Pavon, J.
Title N_eff in low-scale seesaw models versus the lightest neutrino mass Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 90 Issue 6 Pages 065033 - 12pp
Keywords
Abstract We evaluate the contribution to N_eff of the extra sterile states in low-scale type I seesaw models (with three extra sterile states). We explore the full parameter space and find that at least two of the heavy states always reach thermalization in the early Universe, while the third one might not thermalize provided the lightest neutrino mass is below O(10(-3) eV). Constraints from cosmology therefore severely restrict the spectra of heavy states in the range 1 eV-100 MeV. The implications for neutrinoless double beta decay are also discussed.
Address [Hernandez, P.; Kekic, M.] Univ Valencia, IFIC CSIC, E-46071 Valencia, Spain, Email: m.pilar.hernandez@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 (down) WOS:000344108100004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2001
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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Observation of charmonium pairs produced exclusively in pp collisions Type Journal Article
Year 2014 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 41 Issue 11 Pages 115002 - 17pp
Keywords QCD; diffraction; charmonia
Abstract A search is performed for the central exclusive production of pairs of charmonia produced in proton-proton collisions. Using data corresponding to an integrated luminosity of 3 fb(-1) collected at centre-of-mass energies of 7 and 8 TeV, J/psi J/psi and J/psi psi (2S) pairs are observed, which have been produced in the absence of any other activity inside the LHCb acceptance that is sensitive to charged particles in the pseudorapidity ranges (-3.5,-1.5) and (1.5, 5.0). Searches are also performed for pairs of P-wave charmonia and limits are set on their production. The cross-sections for these processes, where the dimeson system has a rapidity between 2.0 and 4.5, are measured to be sigma (J/psi J/psi) = 58 +/- 10(stat) +/- 6(syst) pb, sigma(J/psi psi(2S)) = 63(-18)(+27)(stat) +/- 10(syst) pb, sigma(psi(2S)psi(2S)) < 237 pb, sigma(chi)(chi)(C0)(C0) < 69 nb, sigma(chi)(chi)(C1)(C1) < 45 pb, sigma(chi)(chi)(C2)(C2) < 141 pb, where the upper limits are set at the 90% confidence level. The measured J/psi J/psi and J/psi psi (2S) cross-sections are consistent with theoretical expectations.
Address [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Massafferri, A.; Rodrigues, B. Osorio; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: ronan.mcnulty@ucd.ie
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 0954-3899 ISBN Medium
Area Expedition Conference
Notes (down) WOS:000344090500011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1992
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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the CKM angle gamma using B-+/- -> DK +/- with D -> K-S(0)pi(+)pi(-), (KSK+K-)-K-0 decays Type Journal Article
Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 097 - 52pp
Keywords CP violation; CKM angle gamma; Hadron-Hadron Scattering; B physics; Flavor physics
Abstract A binned Dalitz plot analysis of B-+/- -> DK +/- decays, with D -> K-S(0) pi(+)pi(-) and D -> K0 S K + K -, is performed to measure the C P -violating observables x(+/-) and y(+/-), which are sensitive to the Cabibbo-Kobayashi-Maskawa angle gamma. The analysis exploits a sample of proton-proton collision data corresponding to 3.0 fb(-1) collected by the LHCb experiment. Measurements from CLEO-c of the variation of the strong-interaction phase of the D decay over the Dalitz plot are used as inputs. The values of the parameters are found to be x(+) = (-7.7 +/- 2.4 +/- 1.0 +/- 0.4) x 10(-2), x(-) = (2.5 +/- 2.5 +/- 1.0 +/- 0.5) x 10(-2), y(+) = (-2.2 +/- 2.5 +/- 0.4 +/- 1.0) x 10-2, and y(-) = (7.5 +/- 2.9 +/- 0.5 +/- 1.4) x 10(-2). The first, second, and third uncertainties are the statistical, the experimental systematic, and that associated with the precision of the strong-phase parameters. These are the most precise measurements of these observables and correspond to +/- = (62(-14)(+15))degrees, with a second solution at gamma -> gamma + 180 degrees, and r(B) = 0.080(-0.021)(+0.019), where r(B) is the ratio between the suppressed and favoured B decay amplitudes.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: s.malde1@physics.ox.ac.uk
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes (down) WOS:000344077300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1981
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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the (B)over-bar(s)(0) Meson Lifetime in D-s(+)pi(-) Decays Type Journal Article
Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 113 Issue 17 Pages 172001 - 9pp
Keywords
Abstract We present a measurement of the ratio of the (B) over bar (0)(s) meson lifetime, in the flavor-specific decay to D-s(+)pi(-), to that of the (B) over bar (0) meson. The pp collision data used correspond to an integrated luminosity of 1 fb(-1), collected with the LHCb detector, at a center-of-mass energy of 7 TeV. Combining our measured value of 1.010 +/- 0.010 +/- 0.008 for this ratio with the known (B) over bar (0) lifetime, we determine the flavor-specific (B) over bar (0)(s) lifetime to be tau((B) over bar (0)(s) ) = 1.535 +/- 0.015 +/- 0.014 ps, where the uncertainties are statistical and systematic, respectively. This is the most precise measurement to date, and is consistent with previous measurements and theoretical predictions.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil
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 (down) WOS:000344056800002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1995
Permanent link to this record