Records |
Author |
Sobczyk, J.E.; Rocco, N.; Lovato, A.; Nieves, J. |
Title |
Weak production of strange and charmed ground-state baryons in nuclei |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
99 |
Issue |
6 |
Pages |
065503 - 16pp |
Keywords |
|
Abstract |
We present results for the quasielastic weak production of Delta and Sigma hyperons induced by (nu) over bar. scattering off nuclei in the kinematical region of interest for accelerator neutrino experiments. We employ realistic hole spectral functions and we describe the propagation of the hyperons in the nuclear medium by means of a Monte Carlo cascade. The latter strongly modifies the kinematics and the relative production rates of the hyperons, leading to a nonvanishing Sigma(+) cross section, to a sizable enhancement of the Lambda production and to a drastic reduction of the Sigma(0) and Sigma(-) distributions. We also compute the quasielastic weak Lambda(c) production cross section, paying special attention to estimate the uncertainties induced by the model dependence of the vacuum n -> Lambda(c) weak matrix element. In this regard, the recent BESIII measurements of the branching ratios of Lambda(c) -> Lambda l(+)nu(l) (l = e, mu) are used to benchmark the available theoretical predictions. |
Address |
[Sobczyk, J. E.; Nieves, And J.] Univ Valencia, Inst Invest Patema, CSIC, Inst Fis Corpuscular IFIC,Ctr Mixto, Apartado 22085, 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 |
2469-9985 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Medium |
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Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000471984800003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4059 |
Permanent link to this record |
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Author |
Xiao, C.W.; Nieves, J.; Oset, E. |
Title |
Heavy quark spin symmetric molecular states from (D)over-bar(()*())Sigma(()(c)*()) and other coupled channels in the light of the recent LHCb pentaquarks |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
100 |
Issue |
1 |
Pages |
014021 - 6pp |
Keywords |
|
Abstract |
We consider the (D) over bar (()*())Sigma(()(c)*()) states, together with J/psi N and other coupled channels, and take an interaction consistent with heavy quark spin symmetry, with the dynamical input obtained from an extension of the local hidden gauge approach. By fitting only one parameter to the recent three pentaquark states reported by the LHCb Collaboration, we can reproduce the three of them in base to the mass and the width, providing for them the quantum numbers and approximate molecular structure as 1/2(-) (D) over bar Sigma(c), 1/2(-) (D) over bar*Sigma(c), and 3/2(-) (D) over bar*Sigma(c), and the isospin I = 1/2. We find another state around 4374 MeV, of the 3/2(-) (D) over bar Sigma(c)* structure, for which indications appear in the experimental spectrum. Two other near degenerate states of a 1/2(-) (D) over bar*Sigma(c)* and 3/2(-) (D) over bar*Sigma(c)* nature are also found around 4520 MeV, which although less clear, are not incompatible with the observed spectrum. In addition, a 5/2(-) (D) over bar*Sigma(c)* state at the same energy appears, which however does not couple to J/psi p in an S wave, and hence, it is not expected to show up in the LHCb experiment. |
Address |
[Xiao, C. W.] Cent S Univ, Sch Phys & Elect, Changsha 410083, Hunan, Peoples R China |
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 |
2470-0010 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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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:000476694500003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4086 |
Permanent link to this record |
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Author |
Sobczyk, J.E.; Rocco, N.; Nieves, J. |
Title |
Polarization of tau in quasielastic (anti)neutrino scattering: The role of spectral functions |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
100 |
Issue |
3 |
Pages |
035501 - 14pp |
Keywords |
|
Abstract |
We present a study of the tau polarization in charged-current quasielastic (anti)neutrino-nucleus scattering. The spectral function formalism is used to compute the differential cross section and the polarization components for several kinematical setups, relevant for neutrino-oscillation experiments. The effects of the nuclear corrections in these observables are investigated by comparing the results obtained using two different realistic spectral functions, with those deduced from the relativistic global Fermi gas model, where only statistical correlations are accounted for. We show that the spectral functions, although they play an important role when predicting the differential cross sections, produce much less visible effects on the polarization components of the outgoing tau. |
Address |
[Sobczyk, J. E.; Nieves, J.] Univ Valencia, Ctr Mixto CSIC, Inst Fis Corpuscular IFIC, Inst Invest Paterna, Apartado 22085, 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 |
|
Edition |
|
ISSN |
2469-9985 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000483582500009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4126 |
Permanent link to this record |
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Author |
Xiao, C.W.; Nieves, J.; Oset, E. |
Title |
Prediction of hidden charm strange molecular baryon states with heavy quark spin symmetry |
Type |
Journal Article |
Year |
2019 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
799 |
Issue |
|
Pages |
135051 - 10pp |
Keywords |
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Abstract |
We have studied the meson-baryon S-wave interaction in the isoscalar hidden-charm strange sector with the coupled-channels, eta(c)Lambda, J/psi Lambda, (D) over bar Xi(c), (D) over bar (s)Lambda(c), (D) over bar Xi(c)', (D) over bar*Lambda(c), (D) over bar*Xi(c)', (D) over bar*Xi*(c) in J(p) = 1/2(-), J/psi Lambda, (D) over bar*Xi(c), (D) over bar (s)*Lambda(c), (D) over bar*Xi(c)', (D) over bar Xi(c)*, (D) over bar*Xi(c)* in 3/2(-) and (D) over bar*Xi(c)* in 5/2(-). We impose constraints of heavy quark spin symmetry in the interaction and obtain the non vanishing matrix elements from an extension of the local hidden gauge approach to the charm sector. The ultraviolet divergences are renormalized using the same meson-baryon-loops regulator previously employed in the non-strange hidden charm sector, where a good reproduction of the properties of the newly discovered pentaquark states is obtained. We obtain five states of 1/2(-), four of 3/2(-) and one of 5/2(-), which could be compared in the near future with forthcoming LHCb experiments. The 5/2(-), three of the 3/2(-) and another three of the 1/2(-) resonances are originated from isoscalar (D) over bar (()*())Xi(c)' and (D) over bar (()*()) Xi(c)* interactions. They should be located just few MeV below the corresponding thresholds (4446, 4513, 4588 and 4655 MeV), and would be SU(3)-siblings of the isospin 1/2 (D) over bar (()*())Sigma(()(c)*()) quasi-bound states previously found, and that provided a robust theoretical description of the P-c(4440), P-c(4457) and P-c(4312) LHCb exotic states. The another two 1/2(-) and 3/2(-) states obtained in this work are result of the (D) over bar (()*())Xi(c)- D-s(()*()) Lambda(c) coupled-channels isoscalar interaction, are significantly broader than the others, with widths of the order of 15 MeV, being (D) over bar (()(s)*())Lambda(c) the dominant decay channel. |
Address |
[Xiao, C. W.] Cent S Univ, Sch Phys & Elect, Changsha 410083, Hunan, Peoples R China, Email: jmnieves@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
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 |
0370-2693 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000500331400020 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4216 |
Permanent link to this record |
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Author |
Penalva, N.; Hernandez, E.; Nieves, J. |
Title |
Further tests of lepton flavor universality from the charged lepton energy distribution in b -> c semileptonic decays: The case of Lambda(b) -> Lambda(c) l(v)over-bar(l) |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
100 |
Issue |
11 |
Pages |
113007 - 11pp |
Keywords |
|
Abstract |
In a general framework, valid for any H -> H' l(-)(v) over bar (l) semileptonic decay, we analyze the d(2)Gamma/(d omega d cos theta(l)) and d(2)Gamma/(d omega dE(l)) distributions, with omega being the product of the hadron four-velocities, theta(l) the angle made by the three-momenta of the charged lepton and the final hadron in the W- center of mass frame and E-l the charged lepton energy in the decaying hadron rest frame. Within the Standard Model (SM), d(2)Gamma/(d omega dE(l)) proportional to (c(0) (omega) c(1) (omega)E-l/M + c(2) (omega)E-l(2)/M-2), with M the initial hadron mass. We find that c(2) (omega) is independent of the lepton flavor and thus it is an ideal candidate to look for lepton flavor universality (LFU) violations. We also find a correlation between the a(2) (omega) structure function, which governs the (cos theta(l))(2) dependence of d(2)Gamma/(d omega d cos theta(l)), and c(2) (omega). Apart from trivial kinematical and mass factors, the ratio of a(2) (omega)/c(2) (omega) is a universal function that can be measured in any semileptonic decay, involving not only b -> c transitions. These two SM predictions can be used as new tests in the present search for signatures of LFU violations. We also generalize the formalism to account for some new physics (NP) terms, and show that neither c(2) nor a(2) are modified by left and right scalar NP terms, being however sensitive to left and right vector corrections. We also find that the a(2)/c(2) ratio is not modified by these latter NP contributions. Finally, and in order to illustrate our findings, we apply our general framework to the Lambda(b) -> Lambda(c)l (v) over bar (l) decay. We show that a measurement of c(2) (or a(2)) for tau decay would not only be a direct measurement of the possible existence of NP, but it would also allow to distinguish from NP fits to b -> c tau(v) over bar (tau) anomalies in the meson sector, which otherwise give the same total and differential d Gamma/d omega widths. We show that the same occurs for the other two terms, c(0) and c(1), that appear in d(2)Gamma/(d omega dE(l)), and for the cos theta(l) linear term of the angular distribution. |
Address |
[Penalva, Neus; Nieves, Juan] Ctr Mixto CSIC UV, Inst Invest Paterna, Inst Fis Corpuscular, Apartado 22085, 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 |
2470-0010 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000503400600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
4230 |
Permanent link to this record |