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Author Nieves, J.; Feijoo, A.; Albaladejo, M.; Du, M.L.
Title Lowest-lying 1/2- and 3/2- ΛQ resonances: From the strange to the bottom sectors Type Journal Article
Year 2024 Publication (down) Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume 137 Issue Pages 104118 - 23pp
Keywords Heavy quark symmetry; Constituent quark-model; Molecule; Charmed; Bottomed
Abstract We present a detailed study of the lowest-lying 1/2(-) and 3/2(-) Lambda Q resonances both in the heavy 2 2 quark (bottom and charm) and the strange sectors. We have paid special attention to the interplay between the constituent quark-model and chiral baryon-meson degrees of freedom, which are coupled using a unitarized scheme consistent with leading-order heavy quark symmetries. We show that the Lambda(b)(5912) [J(P) = 1/2(-)], Lambda(b)(5920) [J(P) = 3/2(-)] and the Lambda(c)(2625) [J(P) = 3/2-], and the Lambda(1520) [J(P) = 3/2(-)] admitting larger breaking corrections, are heavyquark spin-flavor siblings. They can be seen as dressed quark-model states with Sigma Q(()*()) pi molecular components of the order of 30%. The J(P)=1(-) Lambda(2595) has, however, a higher molecular 2 probability of at least 50%, and even values greater than 70% can be easily accommodated. This is because it is located almost on top of the threshold of the Sigma(c)pi pair, which largely influences its properties. Although the light degrees of freedom in this resonance would be coupled to spin-parity 1(-) as in the Lambda(b)(5912), Lambda(b)(5920) and Lambda(c)(2625), the Lambda(c)(2595) should not be considered as a heavy-quark spin-flavor partner of the former ones. We also show that the Lambda(1405) chiral two-pole pattern does not have analogs in the 1 – charmed and bottomed sectors, because the 2 N D-(*()) and N (B) over bar (()*()) channels do not play for heavy quarks the decisive role that the N (K) over bar does in the strange sector, and the notable influence of the bare quark-model states for the charm and bottom resonances. Finally, we predict the existence of two Lambda(b)(6070) and two Lambda(c)(2765) heavy-quark spin and flavor sibling odd parity states.
Address [Nieves, J.; Feijoo, A.; Albaladejo, M.] Inst Fis Corpuscular, Ctr Mixto, CSIC UV, Valencia, Spain, Email: jmnieves@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:001243410100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6153
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Author Casas, F.; Oteo, J.A.; Ros, J.
Title Unitary transformations depending on a small parameter Type Journal Article
Year 2012 Publication (down) Proceedings of the Royal Society A Abbreviated Journal Proc. R. Soc. A
Volume 468 Issue 2139 Pages 685-700
Keywords perturbation theory; quantum mechanics; unitary transformation; Magnus expansion
Abstract We formulate a unitary perturbation theory for quantum mechanics inspired by the Lie-Deprit formulation of canonical transformations. The original Hamiltonian is converted into a solvable one by a transformation obtained through a Magnus expansion. This ensures unitarity at every order in a small parameter. A comparison with the standard perturbation theory is provided. We work out the scheme up to order ten with some simple examples.
Address [Oteo, J. A.; Ros, J.] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: rosj@uv.es
Corporate Author Thesis
Publisher Royal Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1364-5021 ISBN Medium
Area Expedition Conference
Notes WOS:000300185400005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 893
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Author Alioli, S.; Fuster, J.; Irles Quiles, A.; Moch, S.; Uwer, P.; Vos, M.
Title A new observable to measure the top quark mass at hadron colliders Type Journal Article
Year 2012 Publication (down) Pramana-Journal of Physics Abbreviated Journal Pramana-J. Phys.
Volume 79 Issue 4 Pages 809-812
Keywords Top quark; mass; pole mass; NLO; cross-section; t(t)over-bar plus jet; POWHEG; perturbative QCD
Abstract The t (t) over bar + jet + X differential cross-section in proton-proton collisions at 7 TeV centre of mass energy is investigated with respect to its sensitivity to the top quark mass. The analysis includes higher order QCD corrections at NLO. The impact of the renormalization scale (mu(R)), the factorization (mu(F)) scale and of the choice of different proton's PDF (parton distribution function) has been evaluated. In this study it is concluded that differential jet rates offer a promising option for alternative mass measurements of the top quark, with theoretical uncertainties below 1 GeV.
Address [Fuster, Juan; Irles, Adrian; Vos, Marcel] Univ Valencia, Ctr Mixte, CSIC, IFIC, E-46071 Valencia, Spain, Email: airqui@ific.uv.es
Corporate Author Thesis
Publisher Indian Acad Sciences Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-4289 ISBN Medium
Area Expedition Conference
Notes WOS:000310875900021 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1200
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Author Botella-Soler, V.; Valderrama, M.; Crepon, B.; Navarro, V.; Le Van Quyen, M.
Title Large-Scale Cortical Dynamics of Sleep Slow Waves Type Journal Article
Year 2012 Publication (down) Plos One Abbreviated Journal PLoS One
Volume 7 Issue 2 Pages e30757 - 10pp
Keywords
Abstract Slow waves constitute the main signature of sleep in the electroencephalogram (EEG). They reflect alternating periods of neuronal hyperpolarization and depolarization in cortical networks. While recent findings have demonstrated their functional role in shaping and strengthening neuronal networks, a large-scale characterization of these two processes remains elusive in the human brain. In this study, by using simultaneous scalp EEG and intracranial recordings in 10 epileptic subjects, we examined the dynamics of hyperpolarization and depolarization waves over a large extent of the human cortex. We report that both hyperpolarization and depolarization processes can occur with two different characteristic time durations which are consistent across all subjects. For both hyperpolarization and depolarization waves, their average speed over the cortex was estimated to be approximately 1 m/s. Finally, we characterized their propagation pathways by studying the preferential trajectories between most involved intracranial contacts. For both waves, although single events could begin in almost all investigated sites across the entire cortex, we found that the majority of the preferential starting locations were located in frontal regions of the brain while they had a tendency to end in posterior and temporal regions.
Address [Botella-Soler, Vicente] Univ Valencia, Dept Fis Teor, CSIC, Valencia, Spain, Email: quyen@t-online.de
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:000302853600065 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 986
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Author Valderrama, M.; Crepon, B.; Botella-Soler, V.; Martinerie, J.; Hasboun, D.; Alvarado-Rojas, C.; Baulac, M.; Adam, C.; Navarro, V.; Le Van Quyen, M.
Title Human Gamma Oscillations during Slow Wave Sleep Type Journal Article
Year 2012 Publication (down) Plos One Abbreviated Journal PLoS One
Volume 7 Issue 4 Pages e33477 - 14pp
Keywords
Abstract Neocortical local field potentials have shown that gamma oscillations occur spontaneously during slow-wave sleep (SWS). At the macroscopic EEG level in the human brain, no evidences were reported so far. In this study, by using simultaneous scalp and intracranial EEG recordings in 20 epileptic subjects, we examined gamma oscillations in cerebral cortex during SWS. We report that gamma oscillations in low (30-50 Hz) and high (60-120 Hz) frequency bands recurrently emerged in all investigated regions and their amplitudes coincided with specific phases of the cortical slow wave. In most of the cases, multiple oscillatory bursts in different frequency bands from 30 to 120 Hz were correlated with positive peaks of scalp slow waves (“IN-phase'' pattern), confirming previous animal findings. In addition, we report another gamma pattern that appears preferentially during the negative phase of the slow wave (”ANTI-phase'' pattern). This new pattern presented dominant peaks in the high gamma range and was preferentially expressed in the temporal cortex. Finally, we found that the spatial coherence between cortical sites exhibiting gamma activities was local and fell off quickly when computed between distant sites. Overall, these results provide the first human evidences that gamma oscillations can be observed in macroscopic EEG recordings during sleep. They support the concept that these high-frequency activities might be associated with phasic increases of neural activity during slow oscillations. Such patterned activity in the sleeping brain could play a role in off-line processing of cortical networks.
Address [Valderrama, Mario; Crepon, Benoit; Martinerie, Jacques; Hasboun, Dominique; Alvarado-Rojas, Catalina; Baulac, Michel; Adam, Claude; Navarro, Vincent; Le Van Quyen, Michel] Univ Paris 06, Ctr Rech Inst Cerveau & Moelle Epiniere CRICM, INSERM,UMRS 975, Hop La Pitie Salpetriere,CNRS,UMR 7225, Paris, France, Email: quyen@t-online.de
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:000304855200013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1058
Permanent link to this record