Records |
Author |
Celis, A.; Jung, M.; Li, X.Q.; Pich, A. |
Title |
Scalar contributions to b -> c(u) tau nu transitions |
Type |
Journal Article |
Year |
2017 |
Publication |
Physics Letters B |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
Phys. Lett. B |
Volume |
771 |
Issue |
|
Pages |
168-179 |
Keywords |
|
Abstract |
We perform a comprehensive analysis of scalar contributions in b -> c tau nu transitions including the latest measurements of R(D-(*)), the q(2) differential distributions in B -> D-(*) tau nu the tau polarization asymmetry for B -> D*tau nu, and the bound derived from the total width of the B-c meson. We find that scalar contributions with the simultaneous presence of both left- and right-handed couplings to quarks can explain the available data, specifically R(D-(*)) together with the measured differential distributions. However, the constraints from the total B-c width present a slight tension with the current data on B -> D*tau nu in this scenario, preferring smaller values for R(D*). We discuss possibilities to disentangle scalar new physics from other new-physics scenarios like the presence of only a left-handed vector current, via additional observables in B -> D(*)tau nu decays or additional decay modes like the baryonic Lambda(b) -> Lambda(c)tau nu and the inclusive B -> X-c tau nu decays. We also analyze scalar contributions in b -> u tau nu transitions, including the latest measurements of B -> tau nu providing predictions for Lambda(b) -> p tau nu and B -> pi tau nu decays. The potential complementarity between the b -> u and b -> c sectors is finally investigated once assumptions about the flavour structure of the underlying theory are made. |
Address |
[Celis, Alejandro] Ludwig Maximilians Univ Munchen, Fak Phys, Arnold Sommerfeld Ctr Theoret Phys, D-80333 Munich, Germany, Email: xqli@itp.ac.cn |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
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Medium |
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Area |
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Expedition |
|
Conference |
|
Notes |
WOS:000406183300024 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3260 |
Permanent link to this record |
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Author |
Pich, A.; Rodriguez-Sanchez, A. |
Title |
Updated determination of alpha(s)(m(tau)(2)) from tau decays |
Type |
Journal Article |
Year |
2016 |
Publication |
Modern Physics Letters A |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
Mod. Phys. Lett. A |
Volume |
31 |
Issue |
30 |
Pages |
1630032 - 15pp |
Keywords |
QCD; strong coupling; tau decays |
Abstract |
Using the most recent release of the ALEPH tau decay data, we present a very detailed phenomenological update of the alpha(s)(m(tau)(2)) determination. We have exploited the sensitivity to the strong coupling in many different ways, exploring several complementary methodologies. All determinations turn out to be in excellent agreement, allowing us to extract a very reliable value of the strong coupling. We find alpha((nf =3))(s)(m(tau)(2)) = 0.328 +/- 0.012 which implies alpha((nf=5))(s)(M-Z(2)) = 0.1197 +/- 0.0014. We critically revise previous work, and point out the problems flawing some recent analyses which claim slightly smaller values. |
Address |
[Pich, Antonio; Rodriguez-Sanchez, Antonio] Univ Valencia, IFIC, CSIC, Dept Fis Teor, Apt Correus 22085, F-46071 Valencia, Spain, Email: Antonio.Pich@ific.uv.es; |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte Ltd |
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 |
0217-7323 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000383788500002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2818 |
Permanent link to this record |
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Author |
Jung, M.; Pich, A.; Tuzon, P. |
Title |
Charged-Higgs phenomenology in the aligned two-Higgs-doublet model |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
J. High Energy Phys. |
Volume |
11 |
Issue |
11 |
Pages |
003 - 45pp |
Keywords |
Higgs Physics; Beyond Standard Model; CP violation |
Abstract |
The alignment in flavour space of the Yukawa matrices of a general two-Higgs-doublet model results in the absence of tree-level flavour-changing neutral currents. In addition to the usual fermion masses and mixings, the aligned Yukawa structure only contains three complex parameters zeta(f), which are potential new sources of CP violation [1]. For particular values of these three parameters all known specific implementations of the model based on discrete Z(2) symmetries are recovered. One of the most distinctive features of the two-Higgs-doublet model is the presence of a charged scalar H-+/-. In this work, we discuss its main phenomenological consequences in flavour-changing processes at low energies and derive the corresponding constraints on the parameters of the aligned two-Higgs-doublet model. |
Address |
[Jung, Martin; Pich, Antonio; Tuzon, Paula] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, E-46071 Valencia, Spain, Email: jung@ific.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 |
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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 |
1126-6708 |
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 |
ISI:000284963400078 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
317 |
Permanent link to this record |
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Author |
Pich, A.; Rosell, I.; Sanz-Cillero, J.J. |
Title |
The vector form factor at the next-to-leading order in 1/N-C: chiral couplings L-9(mu) and C-88(mu)-C-90(mu) |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
J. High Energy Phys. |
Volume |
02 |
Issue |
2 |
Pages |
109 - 23pp |
Keywords |
1/N Expansion; Chiral Lagrangians; QCD |
Abstract |
Using the Resonance Chiral Theory Lagrangian, we perform a calculation of the vector form factor of the pion at the next-to-leading order (NLO) in the 1/N-C expansion. Imposing the correct QCD short-distance constraints, one fixes the amplitude in terms of the pion decay constant F and resonance masses. Its low momentum expansion determines then the corresponding O(p(4)) and O(p(6)) low-energy chiral couplings at NLO, keeping control of their renormalization scale dependence. At mu(0) = 0.77 GeV, we obtain L-9(mu(0)) = (7.9 +/- 0.4).10(-3) and C-88(mu(0)) – C-90(mu(0)) = (-4.6 +/- 0.4).10(-5). |
Address |
[Pich, Antonio; Rosell, Ignasi] Univ Valencia CSIC, Dept Fis Teor, IFIC, E-46071 Valencia, Spain, Email: Antonio.Pich@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 |
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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 |
1126-6708 |
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 |
ISI:000287939200009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
620 |
Permanent link to this record |
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Author |
Pich, A.; Rosell, I.; Sanz-Cillero, J.J. |
Title |
One-loop calculation of the oblique S parameter in higgsless electroweak models |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal ![sorted by Abbreviated Journal field, descending order (down)](img/sort_desc.gif) |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
106 - 34pp |
Keywords |
Higgs Physics; Beyond Standard Model; Chiral Lagrangians; Technicolor and Composite Models |
Abstract |
We present a one-loop calculation of the oblique S parameter within Higgsless models of electroweak symmetry breaking and analyze the phenomenological implications of the available electroweak precision data. We use the most general effective Lagrangian with at most two derivatives, implementing the chiral symmetry breaking SU(2)(L) circle times SU(2)(R) -> SU(2)(L+R) with Goldstones, gauge bosons and one multiplet of vector and axial-vector massive resonance states. Using the dispersive representation of Peskin and Takeuchi and imposing the short-distance constraints dictated by the operator product expansion, we obtain S at the NLO in terms of a few resonance parameters. In asymptotically-free gauge theories, the final result only depends on the vector-resonance mass and requires M-V > 1.8TeV (3.8TeV) to satisfy the experimental limits at the 3 sigma (1 sigma) level; the axial state is always heavier, we obtain M-A > 2.5TeV (6.6TeV) at 3 sigma (1 sigma). In strongly-coupled models, such as walking or conformal technicolour, where the second Weinberg sum rule does not apply, the vector and axial couplings are not determined by the short-distance constraints; but one can still derive a lower bound on S, provided the hierarchy M-V < M-A remains valid. Even in this less constrained situation, we find that in order to satisfy the experimental limits at 3 sigma one needs M-V,M-A > 1.8TeV. |
Address |
[Pich, A.; Rosell, I.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, E-46071 Valencia, Spain, Email: antonio.pich@ific.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 |
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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 |
1126-6708 |
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:000309883200063 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1217 |
Permanent link to this record |