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Author Olmo, G.J.; Rubiera-Garcia, D.
Title Importance of torsion and invariant volumes in Palatini theories of gravity Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue (down) 8 Pages 084030 - 11pp
Keywords
Abstract We study the field equations of extensions of general relativity formulated within a metric-affine formalism setting torsion to zero (Palatini approach). We find that different (second-order) dynamical equations arise depending on whether torsion is set to zero (i) a priori or (ii) a posteriori, i.e., before or after considering variations of the action. Considering a generic family of Ricci-squared theories, we show that in both cases the connection can be decomposed as the sum of a Levi-Civita connection and terms depending on a vector field. However, while in case (i) this vector field is related to the symmetric part of the connection, in (ii) it comes from the torsion part and, therefore, it vanishes once torsion is completely removed. Moreover, the vanishing of this torsion-related vector field immediately implies the vanishing of the antisymmetric part of the Ricci tensor, which therefore plays no role in the dynamics. Related to this, we find that the Levi-Civita part of the connection is due to the existence of an invariant volume associated with an auxiliary metric h(mu v), which is algebraically related with the physical metric g(mu v).
Address [Olmo, Gonzalo J.] Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, Valencia 46100, Spain, Email: gonzalo.olmo@csic.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:000326107300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1630
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P.
Title Differential branching fraction and angular analysis of the decay B-0 -> K*(0)mu(+)mu(-) Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue (down) 8 Pages 131 - 31pp
Keywords Rare decay; Hadron-Hadron Scattering; B physics; Flavour Changing Neutral Currents; Flavor physics
Abstract The angular distribution and differential branching fraction of the decay B-0 -> K*(0)mu(+)mu(-) are studied using a data sample, collected by the LHCb experiment in pp collisions at root s = 7 TeV, corresponding to an integrated luminosity of 1.0 fb(-1). Several angular observables are measured in bins of the dimuon invariant mass squared, q(2). A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q(0)(2) = 4.9 +/- 0.9 GeV2/c(4), where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: thomas.blake@cern.ch
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 WOS:000324114000032 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1683
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Author Gillam, J.E.; Solevi, P.; Oliver, J.F.; Rafecas, M.
Title Simulated one-pass list-mode: an approach to on-the-fly system matrix calculation Type Journal Article
Year 2013 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 58 Issue (down) 7 Pages 2377-2394
Keywords
Abstract In the development of prototype systems for positron emission tomography a valid and robust image reconstruction algorithm is required. However, prototypes often employ novel detector and system geometries which may change rapidly under optimization. In addition, developing systems generally produce highly granular, or possibly continuous detection domains which require some level of on-the-fly calculation for retention of measurement precision. In this investigation a new method of on-the-fly system matrix calculation is proposed that provides advantages in application to such list-mode systems in terms of flexibility in system modeling. The new method is easily adaptable to complicated system geometries and available computational resources. Detection uncertainty models are used as random number generators to produce ensembles of possible photon trajectories at image reconstruction time for each datum in the measurement list. However, the result of this approach is that the system matrix elements change at each iteration in a non-repetitive manner. The resulting algorithm is considered the simulation of a one-pass list (SOPL) which is generated and the list traversed during image reconstruction. SOPL alters the system matrix in use at each iteration and so behavior within the maximum likelihood-expectation maximization algorithm was investigated. A two-pixel system and a small two dimensional imaging model are used to illustrate the process and quantify aspects of the algorithm. The two-dimensional imaging system showed that, while incurring a penalty in image resolution, in comparison to a non-random equal-computation counterpart, SOPL provides much enhanced noise properties. In addition, enhancement in system matrix quality is straightforward (by increasing the number of samples in the ensemble) so that the resolution penalty can be recovered when desired while retaining improvement in noise properties. Finally the approach is tested and validated against a standard (highly accurate) system matrix using experimental data from a prototype system-the AX-PET.
Address [Gillam, J. E.; Solevi, P.; Oliver, J. F.; Rafecas, M.] Univ Valencia, CSIC, IFIC, Inst Fis Corpuscular, Valencia, Spain, Email: john.gillam@ific.uv.es
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 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000316181300024 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1370
Permanent link to this record
 
 
Author Hidalgo-Duque, C.; Nieves, J.; Pavon Valderrama, M.
Title Light flavor and heavy quark spin symmetry in heavy meson molecules Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue (down) 7 Pages 076006 - 14pp
Keywords
Abstract We propose an effective field theory incorporating light SU(3)-flavor and heavy quark spin symmetry to describe charmed meson-antimeson bound states. At lowest order the effective field theory entails a remarkable simplification: it only involves contact range interactions among the heavy meson and antimeson fields. We show that the isospin violating decays of the X(3872) can be used to constrain the interaction between the D and a (D) over bar* mesons in the isovector channel. As a consequence, we can rule out the existence of an isovector partner of the X(3872). If we additionally assume that the X(3915) and Y(4140) are D*(D) over bar* and D*(s)(D) over bar*(s) molecular states, we can determine the full spectrum of molecular states with isospin I = 0, 1/2 and 1.
Address Univ Valencia, Inst Fis Corpuscular IFIC, Ctr Mixto CSIC, Inst Invest Paterna, E-46071 Valencia, Spain, Email: pavonvalderrama@ipno.in2p3.fr
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:000317197800010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1395
Permanent link to this record
 
 
Author Arbelaez, C.; Fonseca, R.M.; Romao, J.C.; Hirsch, M.
Title Supersymmetric SO(10)-inspired GUTs with sliding scales Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue (down) 7 Pages 075010 - 19pp
Keywords
Abstract We construct lists of supersymmetric models with extended gauge groups at intermediate steps, all of which are inspired by SO(10) unification. We consider three different kinds of setups: (i) the model has exactly one additional intermediate scale with a left-right (LR) symmetric group; (ii) SO(10) is broken to the LR group via an intermediate Pati-Salam scale; and (iii) the LR group is broken into SU(3)(c) X SU(2)(L) X U(1)(R) X U(1)(B-L), before breaking to the standard model (SM) group. We use sets of conditions, which we call the “sliding mechanism,” which yield unification with the extended gauge group(s) allowed at arbitrary intermediate energy scales. All models thus can have new gauge bosons within the reach of the LHC, in principle. We apply additional conditions, such as perturbative unification, renormalizability and anomaly cancellation and find that, despite these requirements, for the ansatz (i) with only one additional scale still around 50 different variants exist that can have a LR symmetry below 10 TeV. For the more complicated schemes (ii) and (iii) literally thousands of possible variants exist, and for scheme (ii) we have also found variants with very low Pati-Salam scales. We also discuss possible experimental tests of the models from measurements of supersymmetry masses. Assuming mSugra boundary conditions we calculate certain combinations of soft terms, called “invariants,” for the different classes of models. Values for all the invariants can be classified into a small number of sets, which contain information about the class of models and, in principle, the scale of beyond-minimal supersymmetric extension of the Standard Model physics, even in case the extended gauge group is broken at an energy beyond the reach of the LHC.
Address Univ Tecn Lisboa, Dept Fis, P-1049001 Lisbon, Portugal, Email: Carolina.Arbelaez@ist.utl.pt;
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:000317586900007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1401
Permanent link to this record
 
 
Author Chachamis, G.; Hentschinski, M.; Madrigal Martinez, J.D.; Sabio Vera, A.
Title Next-to-leading order corrections to the gluon-induced forward jet vertex from the high energy effective action Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue (down) 7 Pages 076009 - 11pp
Keywords
Abstract We determine both real and virtual next-to-leading order corrections to the gluon-induced forward jet vertex from the high energy effective action proposed by Lipatov. For these calculations we employ the same regularization and subtraction formalism developed in our previous work on the quark-initiated vertex. We find agreement with previous results in the literature.
Address UVEG, CSIC, Inst Fis Corpuscular, Valencia 46980, 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:000317866500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1410
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P.
Title Observation of the decay B-c(+) -> psi(2S)pi(+) Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue (down) 7 Pages 071103 - 7pp
Keywords
Abstract The decay B-c(+) -> psi(2S)pi(+) with psi(2S) -> mu(+)mu(-) is observed with a significance of 5.2 sigma using pp collision data corresponding to an integrated luminosity of 1.0 fb(-1) collected by the LHCb experiment. The branching fraction of B-c(+) -> psi(2S)pi(+) decays relative to that of the B-c(+) -> J/psi pi(+) mode is measured to be B(B-c(+) -> psi(2S)pi(+))/B(B-c(+) -> J/psi pi(+)) = 0.250 +/- 0.068(stat) +/- 0.014(syst) +/- 0.006(B). The last term is the uncertainty on the ratio B(psi(2S) -> mu(+)mu(-))/B(J/psi -> mu(+)mu(-)).
Address 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000318183700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1419
Permanent link to this record
 
 
Author Garcia-Recio, C.; Nieves, J.; Romanets, O.; Salcedo, L.L.; Tolos, L.
Title Hidden charm N and Delta resonances with heavy-quark symmetry Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue (down) 7 Pages 074034 - 23pp
Keywords
Abstract A model is developed to describe odd-parity baryon resonances generated dynamically through a unitary baryon-meson coupled-channels approach. The scheme applies to channels with light- and/or heavy-quark content. Distinct features of the model are that i) the interaction is an S-wave contact one, ii) it reduces to the SU(3) Weinberg-Tomozawa Hamiltonian when light pseudoscalar mesons are involved, thus respecting chiral symmetry, iii) spin-flavor is preserved in the light-quark sector, and iv) heavy-quark spin symmetry is fulfilled in the heavy-quark sector. In particular, baryon-meson states with different content in c or in (c) over bar do not mix. The model is a minimal one and it contains no free parameters. In this work, we focus on baryon resonances with hidden charm (at least one (c) over bar and one c quark). We analyze several possible sectors and, for the sector with zero net charm, we write down the most general Lagrangian consistent with SU(3) and heavy-quark spin symmetry. We explicitly study the N and Delta states, which are produced from the S-wave interaction of pseudoscalar and vector mesons with 1/2(+) and 3/2(+) baryons within the charmless and strangeless hidden-charm sector. We predict seven odd-parity N-like and five Delta-like states with masses around 4 GeV, most of them as bound states. These states form heavy-quark spin multiplets, which are almost degenerate in mass. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and they might be looked for in the forthcoming PANDA experiment at the future FAIR facility.
Address Univ Granada, Dept Fis Atom Mol & Nucl, E-18071 Granada, 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:000318183700004 Approved no
Is ISI yes International Collaboration
Call Number IFIC @ pastor @ Serial 1420
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P.
Title Search for the decay B-s(0) -> D*(-/+)pi(+/-) Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue (down) 7 Pages 071101 - 8pp
Keywords
Abstract A search for the decay B-s(0) -> D*(-/+)pi(+/-) is presented using a data sample corresponding to an integrated luminosity of 1.0 fb(-1) of pp collisions collected by LHCb. This decay is expected to be mediated by a W-exchange diagram, with little contribution from rescattering processes, and therefore a measurement of the branching fraction will help us to understand the mechanism behind related decays such as B-s(0) -> pi(+)pi(-) and B-s(0) -> D (D) over bar. Systematic uncertainties are minimized by using B-0 -> D*(-/+)pi(+/-) as a normalization channel. We find no evidence for a signal, and set an upper limit on the branching fraction of B(B-s(0) -> D*(-/+)pi(+/-) < 6.1(7.8) x 10(-6) at 90% (95%) confidence level.
Address 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000317912600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1422
Permanent link to this record
 
 
Author ANTARES Collaboration (Tamburini, C. et al); Aguilar, J.A.; Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Ruiz-Rivas, J.; Salesa, F.; Sanchez-Losa, A.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J.
Title Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface Type Journal Article
Year 2013 Publication Plos One Abbreviated Journal PLoS One
Volume 8 Issue (down) 7 Pages e67523 - 10pp
Keywords
Abstract The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep waters. Such changes are triggered by the winter cooling and evaporation experienced by the upper ocean layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense water through a process known as “open-sea convection”. It episodically renews the deep water of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep open-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense water formation events are likely to decline under global warming scenarios enhancing ocean stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts.
Address [Tamburini, Christian; Lefevre, Dominique; Martini, Verine; Robert, Anne; Dekeyser, Ivan; Fuda, Jean-Luc] Aix Marseille Univ, CNRS INSU, IRD, MIO,U110, Marseille, France, Email: christian.tamburini@univ-amu.fr;
Corporate Author Thesis
Publisher Public Library Science Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Medium
Area Expedition Conference
Notes WOS:000321765300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1496
Permanent link to this record