Records |
Author |
Gambino, P.; Melis, A.; Simula, S. |
Title |
Extraction of heavy-quark-expansion parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
96 |
Issue |
1 |
Pages |
014511 - 17pp |
Keywords |
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Abstract |
We present a precise lattice computation of pseudoscalar and vector heavy-light meson masses for heavy-quark masses ranging from the physical charm mass up to similar or equal to 4 times the physical b-quark mass. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with N-f = 2 + 1 + 1 dynamical quarks at three values of the lattice spacing (a similar or equal to 0.062; 0.082; 0.089 fm) with pion masses in the range M-pi similar or equal to 210-450 MeV. The heavy-quark mass is simulated directly on the lattice up to similar or equal to 3 times the physical charm mass. The interpolation to the physical b-quark mass is performed using the ETMC ratio method, based on ratios of the meson masses computed at nearby heavy-quark masses, and adopting the kinetic mass scheme. The extrapolation to the physical pion mass and to the continuum limit yields m(b)(kin) (1 GeV) = 4.61(20) GeV, which corresponds to (m) over bar (b) ((m) over bar (b)) 4.26(18) GeV in the (MS) over bar scheme. The lattice data are analyzed in terms of the heavy-quark expansion (HQE) and the matrix elements of dimension-four and dimension-five operators are extracted with a good precision, namely,(Lambda) over bar = 0.552(26) GeV, mu(2)(pi) = 0.321(32) GeV2, and mu(2)(G)(m(b)) = 0.253(25) GeV2. The data also allow for a rough estimate of the dimension-six operator matrix elements. As the HQE parameters play a crucial role in the inclusive determination of the Cabibbo-Kobayashi-Maskawa matrix elements V-ub and V-cb, their precise determination on the lattice may eventually validate and improve the analyses based on fits to the semileptonic moments. |
Address |
[Gambino, P.] Univ Turin, Dipartimento Fis, Via P Giuria 1, I-10125 Turin, Italy |
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 ![sorted by Summary Language field, ascending order (up)](img/sort_asc.gif) |
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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 |
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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:000406298500005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3224 |
Permanent link to this record |
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Author |
Lubicz, V.; Melis, A.; Simula, S. |
Title |
Masses and decay constants of D-(s)* and B-(s)* mesons with N-f=2+1+1 twisted mass fermions |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
96 |
Issue |
3 |
Pages |
034524 - 10pp |
Keywords |
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Abstract |
We present a lattice calculation of the masses and decay constants of D-(s)* and B-(s)* mesons using the gauge configurations produced by the European Twisted Mass Collaboration (ETMC) with N-f=2+1+1 dynamical quarks at three values of the lattice spacing a similar to(0.06-0.09) fm. Pion masses are simulated in the range M-pi similar or equal to(210-450) MeV, while the strange and charm sea-quark masses are close to their physical values. We compute the ratios of vector to pseudoscalar masses and decay constants for various values of the heavy-quark mass mh in the range 0.7m(c)(phys) less than or similar to m(h) less than or similar to 3m(c)(phys). In order to reach the physical b-quark mass, we exploit the Heavy Quark Effective Theory prediction that, in the static limit of infinite heavy-quark mass, the considered ratios are equal to one. At the physical point our results are: M-D*/M-D=1.0769(79), M-D*(s)/M-Ds=1.0751(56), f(D)*/f(D)=1.078(36), f(D)*s/f(Ds)=1.087(20), M-B*/M-B=1.0078(15), M-B*(s)/M-Bs=1.0083(10), f(B)*/f(B)=0.958(22) and f(B)*s/f(Bs)=0.974(10). Combining them with the experimental values of the pseudoscalar meson masses (used as input to fix the quark masses) and the values of the pseudoscalar decay constants calculated by ETMC, we get: M-D*=2013(14) MeV, M-D*(s)=2116(11) MeV, f(D)*=223.5(8.4) MeV, f(D)*(s)=268.8(6.6) MeV, M-B*=5320.5(7.6) MeV, M-B*(s)=5411.36(5.3) MeV, f(B)*=185.9(7.2) MeV and f(B)*(s)=223.1(5.4) MeV. |
Address |
[Lubicz, V.] Univ Roma Tre, Dip Matemat & Fis, I-00146 Rome, Italy |
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 ![sorted by Summary Language field, ascending order (up)](img/sort_asc.gif) |
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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 |
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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:000408626300006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3282 |
Permanent link to this record |
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Author |
Lopez-Ibañez, M.L.; Melis, A.; Jay Perez, M.; Vives, O. |
Title |
Slepton non-universality in the flavor-effective MSSM |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
11 |
Issue |
11 |
Pages |
162 - 27pp |
Keywords |
Quark Masses and SM Parameters; Supersymmetric Standard Model; Super-symmetry Breaking; Supersymmetric Effective Theories |
Abstract |
Supersymmetric theories supplemented by an underlying flavor-symmetry G(f) provide a rich playground for model building aimed at explaining the flavor structure of the Standard Model. In the case where supersymmetry breaking is mediated by gravity, the soft-breaking Lagrangian typically exhibits large tree-level flavor violating e ff ects, even if it stems from an ultraviolet flavor-conserving origin. Building on previous work, we continue our phenomenological analysis of these models with a particular emphasis on leptonicflavor observables. We consider three representative models which aim to explain the flavor structure of the lepton sector, with symmetry groups G(f) = Delta (27), A(4); and S-3. |
Address |
[Luisa Lopez-Ibanez, M.; Melis, Aurora; Jay Perez, M.; Vives, Oscar] Univ Valencia, Dept Fis Teor, Dr Moliner 50, Burjassot, Valencia, Spain, Email: m.luisa.lopez-ibanez@uv.es; |
Corporate Author |
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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 ![sorted by Summary Language field, ascending order (up)](img/sort_asc.gif) |
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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:000416356500006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3382 |
Permanent link to this record |
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Author |
de Medeiros Varzielas, I.; Lopez-Ibañez, M.L.; Melis, A.; Vives, O. |
Title |
Controlled flavor violation in the MSSM from a unified Delta(27) flavor symmetry |
Type |
Journal Article |
Year |
2018 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
09 |
Issue |
9 |
Pages |
047 - 22pp |
Keywords |
Beyond Standard Model; Supersymmetric Standard Model; Quark Masses and SM Parameters |
Abstract |
We study the phenomenology of a unified supersymmetric theory with a flavor symmetry Delta(27). The model accommodates quark and lepton masses, mixing angles and CP phases. In this model, the Dirac and Majorana mass matrices have a unified texture zero structure in the (1, 1) entry that leads to the Gatto-Sartori-Tonin relation between the Cabibbo angle and ratios of the masses in the quark sectors, and to a natural departure from zero of the theta 13(l) angle in the lepton sector. We derive the flavor structures of the trilinears and soft mass matrices, and show their general non-universality. This causes large flavor violating effects. As a consequence, the parameter space for this model is constrained, allowing it to be (dis)proven by flavor violation searches in the next decade. Although the results are model specific, we compare them to previous studies to show similar flavor effects (and associated constraints) are expected in general in supersymmetric flavor models, and may be used to distinguish them. |
Address |
[Varzielas, Ivo de Medeiros] Univ Lisbon, Inst Super Tecn, Dept Fis, CFTP, Ave Rovisco Pais 1, P-1049 Lisbon, Portugal, Email: ivo.de@udo.edu; |
Corporate Author |
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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 ![sorted by Summary Language field, ascending order (up)](img/sort_asc.gif) |
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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:000444676300004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3735 |
Permanent link to this record |
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Author |
Lopez-Ibañez, M.L.; Melis, A.; Meloni, D.; Vives, O. |
Title |
Lepton flavor violation and neutrino masses from A(5) and CP in the non-universal MSSM |
Type |
Journal Article |
Year |
2019 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
06 |
Issue |
6 |
Pages |
047 - 34pp |
Keywords |
Beyond Standard Model; Neutrino Physics; Quark Masses and SM Parameters; Supersymmetric Standard Model |
Abstract |
We analyze the phenomenological consequences of embedding a flavor symmetry based on the groups A(5) and CP in a supersymmetric framework. We concentrate on the leptonic sector, where two different residual symmetries are assumed to be conserved at leading order for charged and neutral leptons. All possible realizations to generate neutrino masses at tree level are investigated. Sizable flavor violating effects in the charged lepton sector are unavoidable due to the non-universality of soft-breaking terms determined by the symmetry. We derive testable predictions for the neutrino spectrum, lepton mixing and flavor changing processes with non-trivial relations among observables. |
Address |
[Lopez-Ibanez, M. L.; Meloni, Davide] Univ Roma Tre, Dipartimento Matemat & Fis, Via Vasca Navale 84, I-00146 Rome, Italy, Email: maloi2@uv.es; |
Corporate Author |
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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 ![sorted by Summary Language field, ascending order (up)](img/sort_asc.gif) |
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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:000471630100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4057 |
Permanent link to this record |