Records |
Author |
ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Jimenez Pena, J.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Mitsou, V.A.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment |
Type |
Journal Article |
Year |
2016 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
064 - 48pp |
Keywords |
Hadron-Hadron scattering; Top physics |
Abstract |
The cross-section for the production of a single top quark in association with a W boson in proton-proton collisions at is measured. The dataset corresponds to an integrated luminosity of 20.3 fb(-1), collected by the ATLAS detector in 2012 at the Large Hadron Collider at CERN. Events containing two leptons and one central b-jet are selected. The W t signal is separated from the backgrounds using boosted decision trees, each of which combines a number of discriminating variables into one classifier. Production of W t events is observed with a significance of 7.7 sigma. The cross-section is extracted in a profile likelihood fit to the classifier output distributions. The W t cross-section, inclusive of decay modes, is measured to be 23.0 +/- 1.3(stat.) (-aEuro parts per thousand 3.5) (+ 3.2) (syst.)+/- 1.1(lumi.) pb. The measured cross-section is used to extract a value for the CKM matrix element |V (tb) | of 1.01 +/- 0.10 and a lower limit of 0.80 at the 95% confidence level. The cross-section for the production of a top quark and a W boson is also measured in a fiducial acceptance requiring two leptons with p (T) > 25 GeV and |eta| < 2.5, one jet with p (T) > 20 GeV and |eta| < 2.5, and E (T) (miss) > 20 GeV, including both W t and top-quark pair events as signal. The measured value of the fiducial cross-section is 0.85 +/- A 0.01(stat.) (-aEuro parts per thousand 0.07) (+ 0.07) (syst.)+/- 0.03(lumi.) pb. |
Address |
[Jackson, P.; Lee, L.; Petridis, A.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368174800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2523 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Study of the production of A(b)(0) and (B)over-bar(0) hadrons in pp collisions and first measurement of the A(b)(0)-> J/psi pK(-) branching fraction |
Type |
Journal Article |
Year |
2016 |
Publication |
Chinese Physics C |
Abbreviated Journal |
Chin. Phys. C |
Volume |
40 |
Issue |
1 |
Pages |
011001 - 16pp |
Keywords |
production cross-section; branching fraction; b hadrons; proton-proton collisions |
Abstract |
The product of the A(b)(0) ((B) over bar (0)) differential production cross-section and the branching fraction of the decay A(b)(0)-> J/psi pK(-) ((B) over bar (0)-> J/psi p (K) over bar*(892)(0)) is measured as a function of the beauty hadron transverse momentum, p(T), and rapidity, y. The kinematic region of the measurements is p(T) <20 GeV/c and 2.0 < y < 4.5. The measurements use a data sample corresponding to an integrated luminosity of 3fb(-1) collected by the LHCb detector in pp collisions at centre-of-mass energies root s=7 TeV in 2011 and root s=8 TeV in 2012. Based on previous LHCb results of the fragmentation fraction ratio, f(Ab0)/f(d), the branching fraction of the decay A(b)(0)-> J/psi pK(-) is measured to be B(A(b)(0)-> J/psi pK(-))=(3.17 +/- 0.04 +/- 0.07 +/- 0.34(-0.28)(+0.45))x10(-4) where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay (B) over bar (0)-> J/psi p (K) over bar*(892)(0), and the fourth is due to the knowledge of f(Ab0)/f(d). The sum of the asymmetries in the production and decay between A(b)(0) and (A) over bar (0)(b) is also measured as a function of p(T) and y. The previously published branching fraction of A(b)(0)-> J/psi p pi(-), relative to that of A(b)(0)-> J/psi pK(-), is updated. The branching fractions of A(b)(0)-> P-c(+)(-> J/psi p)K- are determined. |
Address |
[Bediagal, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodrigues, B. Osorio; Dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
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Thesis |
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Publisher |
Chinese Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1674-1137 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000368221600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2526 |
Permanent link to this record |
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Author |
Perez, A. |
Title |
Asymptotic properties of the Dirac quantum cellular automaton |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review A |
Abbreviated Journal |
Phys. Rev. A |
Volume |
93 |
Issue |
1 |
Pages |
012328 - 10pp |
Keywords |
|
Abstract |
We show that the Dirac quantum cellular automaton [A. Bisio, G. M. D'Ariano, and A. Tosini, Ann. Phys. (N. Y.) 354, 244 (2015)] shares many properties in common with the discrete-time quantum walk. These similarities can be exploited to study the automaton as a unitary process that takes place at regular time steps on a one-dimensional lattice, in the spirit of general quantum cellular automata. In this way, it becomes an alternative to the quantum walk, with a dispersion relation that can be controlled by a parameter that plays a similar role to the coin angle in the quantum walk. The Dirac Hamiltonian is recovered under a suitable limit. We provide two independent analytical approximations to the long-term probability distribution. It is shown that, starting from localized conditions, the asymptotic value of the entropy of entanglement between internal and motional degrees of freedom overcomes the known limit that is approached by the quantum walk for the same initial conditions and is similar to the ones achieved by highly localized states of the Dirac equation. |
Address |
[Perez, A.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, E-46100 Valencia, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1050-2947 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000368291600005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2520 |
Permanent link to this record |
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Author |
Nacher, E.; Rubio, B.; Algora, A.; Cano-Ott, D.; Tain, J.L.; Gadea, A.; Agramunt, J.; Gierlik, M.; Karny, M.; Janas, Z.; Roeckl, E.; Blazhev, A.; Collatz, R.; Doring, J.; Hellstrom, M.; Hu, Z.; Kirchner, R.; Mukha, I.; Plettner, C.; Shibata, M.; Rykaczewski, K.; Batist, L.; Moroz, F.; Wittmann, V.; Valiente-Dobon, J.J. |
Title |
Observations of the Gamow-Teller resonance in the rare-earth nuclei above Gd-146 populated in beta decay |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
93 |
Issue |
1 |
Pages |
014308 - 13pp |
Keywords |
|
Abstract |
The rare-earth region of the nuclear table around the quasi-doubly magic nucleus Gd-146 is one of the very few places in which the Gamow-Teller (GT) resonance can be populated in beta decay. The appropriate technique to study such a phenomenon is total absorption spectroscopy, thanks to which one can measure the B(GT) distribution in beta-decay experiments even when it is very fragmented and lies at high excitation energy in the daughter nucleus. Results on the GT resonance measured in the beta decay of the odd-Z, N = 83 nuclei Tb-148, Ho-150, and Tm-152 are presented in this work and compared with shell-model calculations. The tail of the resonance is clearly observed up to the limit imposed by the Q value. This observation is important in the context of the understanding of the “quenching” of the GT strength. |
Address |
[Nacher, E.; Rubio, B.; Algora, A.; Cano-Ott, D.; Tain, J. L.; Gadea, A.; Agramunt, J.] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain, Email: berta.rubio@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0556-2813 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368298200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2522 |
Permanent link to this record |
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Author |
Aguilar-Saavedra, J.A.; Bernabeu, J. |
Title |
Breaking down the entire W boson spin observables from its decay |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
93 |
Issue |
1 |
Pages |
011301 - 6pp |
Keywords |
|
Abstract |
We discuss the eight independent spin observables for the W boson in terms of its vector and tensor polarizations and identify the angular distributions and asymmetries able to separate them in collider experiments. The results are applied to the study of polarized top quark decays and diboson resonances. These novel observables are of great value for disentangling new physics mechanisms in W boson production. |
Address |
[Aguilar-Saavedra, J. A.] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368324500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2538 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Jimenez Pena, J.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Mitsou, V.A.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Measurement of the correlation between the polar angles of leptons from top quark decays in the helicity basis at root s=7 TeV using the ATLAS detector |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
93 |
Issue |
1 |
Pages |
012002 - 23pp |
Keywords |
|
Abstract |
A measurement of the correlations between the polar angles of leptons from the decay of pair-produced t and (t) over bar quarks in the helicity basis is reported, using proton-proton collision data collected by the ATLAS detector at the LHC. The dataset corresponds to an integrated luminosity of 4.6 fb(-1) at a center-of-mass energy of root s = 7 TeV collected during 2011. Candidate events are selected in the dilepton topology with large missing transverse momentum and at least two jets. The angles theta(1) and theta(2) between the charged leptons and the direction of motion of the parent quarks in the t (t) over bar rest frame are sensitive to the spin information, and the distribution of cos theta(1).cos theta(2) is sensitive to the spin correlation between the t and (t) over bar quarks. The distribution is unfolded to parton level and compared to the next-to-leading order prediction. A good agreement is observed. |
Address |
[Jackson, P.; Lee, L.; Petridis, A.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000368324500002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2537 |
Permanent link to this record |
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Author |
Alvarez-Ruso, L.; Hernandez, E.; Nieves, J.; Vicente Vacas, M.J. |
Title |
Watson's theorem and the N Delta(1232) axial transition |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
93 |
Issue |
1 |
Pages |
014016 - 16pp |
Keywords |
|
Abstract |
We present a new determination of the N Delta axial form factors from neutrino induced pion production data. For this purpose, the model of Hernandez et al. [Phys. Rev. D 76, 033005 (2007)] is improved by partially restoring unitarity. This is accomplished by imposing Watson's theorem on the dominant vector and axial multipoles. As a consequence, a larger C-5(A) (0), in good agreement with the prediction from the off-diagonal Goldberger-Treiman relation, is now obtained. |
Address |
[Alvarez-Ruso, L.; Nieves, J.] Ctr Mixto CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Inst Invest Paterna, E-46071 Valencia, Spain |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368324700003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2521 |
Permanent link to this record |
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Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
Title |
Measurement of the I=1/2 K pi S-wave amplitude from Dalitz plot analyses of eta(c) -> K(K)over-bar pi in two-photon interactions |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
93 |
Issue |
1 |
Pages |
012005 - 16pp |
Keywords |
|
Abstract |
We study the processes gamma gamma -> (KSK +/-)-K-0 pi(-/+) 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) decays to both final states and perform Dalitz plot analyses using a model-independent partial wave analysis technique. This allows a model-independent measurement of the mass-dependence of the I = 1/2 K pi S-wave amplitude and phase. A comparison between the present measurement and those from previous experiments indicates similar behavior for the phase up to a mass of 1.5 GeV/c(2). In contrast, the amplitudes show very marked differences. The data require the presence of a new a(0)(1950) resonance with parameters m = 1931 +/- 14 +/- 22 MeV/c(2) and Gamma = 271 +/- 22 +/- 29 MeV. |
Address |
[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 |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368515900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2536 |
Permanent link to this record |
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Author |
Gonzalez, M.; Kovalenko, S.G.; Hirsch, M. |
Title |
QCD running in neutrinoless double beta decay: Short-range mechanisms |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
93 |
Issue |
1 |
Pages |
013017 - 11pp |
Keywords |
|
Abstract |
The decay rate of neutrinoless double beta (0 nu beta beta) decay contains terms from heavy particle exchange, which lead to dimension-9 (d = 9) six fermion operators at low energies. Limits on the coefficients of these operators have been derived previously neglecting the running of the operators between the high scale, where they are generated, and the energy scale of 0 nu beta beta decay, where they are measured. Here we calculate the leading-order QCD corrections to all possible d = 9 operators contributing to the 0 nu beta beta amplitude and use renormalization group running to calculate 1-loop improved limits. Numerically, QCD running dramatically changes some limits by factors of the order of or larger than typical uncertainties in nuclear matrix element calculations. For some specific cases, operator mixing in the running changes limits even by up to 3 orders of magnitude. Our results can be straightforwardly combined with new experimental limits or improved nuclear matrix element calculations to rederive updated limits on all short-range contributions to 0 nu beta beta decay. |
Address |
[Gonzalez, M.; Kovalenko, S. G.] Univ Tecn Federico Santa Maria, Ctr Cient Tecnol Valparaiso, Casilla 110-V, Valparaiso 2390123, Chile, Email: marcela.gonzalezp@titulados.usm.cl; |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368516100002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2539 |
Permanent link to this record |
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Author |
Aristizabal Sierra, D.; Herrero-Garcia, J.; Restrepo, D.; Vicente, A. |
Title |
Diboson anomaly: Heavy Higgs resonance and QCD vectorlike exotics |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
93 |
Issue |
1 |
Pages |
015012 - 12pp |
Keywords |
|
Abstract |
The ATLAS Collaboration (and also CMS) has recently reported an excess over Standard Model expectations for gauge boson pair production in the invariant mass region 1.8-2.2 TeV. In light of these results, we argue that such a signal might be the first manifestation of the production and further decay of a heavy CP-even Higgs resulting from a type-I two Higgs doublet model. We demonstrate that in the presence of colored vectorlike fermions, its gluon fusion production cross section is strongly enhanced, with the enhancement depending on the color representation of the new fermion states. Our findings show that barring the color triplet case, any QCD “exotic” representation can fit the ATLAS result in fairly large portions of the parameter space. We have found that if the diboson excess is confirmed and this mechanism is indeed responsible for it, then the LHC Run-2 should find (i) a CP-odd scalar with mass below similar to 2.3 TeV, (ii) new colored states with masses below similar to 2 TeV, (iii) no statistically significant diboson events in the W(+/-)Z channel, (iv) events in the triboson channels W(+/-)W(-/+)Z and ZZZ with invariant mass amounting to the mass of the CP-odd scalar. |
Address |
[Sierra, D. Aristizabal] Univ Liege, Dept AGO, IFPA, Bat B5, B-4000 Liege 1, Belgium, Email: daristizabal@ulg.ac.be; |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000368516100007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2535 |
Permanent link to this record |