Records |
Author |
Pich, A.; Rodriguez-Sanchez, A. |
Title |
Determination of the QCD coupling from ALEPH tau decay data |
Type |
Journal Article |
Year |
2016 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
94 |
Issue |
3 |
Pages |
034027 - 26pp |
Keywords |
|
Abstract |
We present a comprehensive study of the determination of the strong coupling from tau decay, using the most recent release of the experimental ALEPH data. We critically review all theoretical strategies used in previous works and put forward various novel approaches which allow one to study complementary aspects of the problem. We investigate the advantages and disadvantages of the different methods, trying to uncover their potential hidden weaknesses and test the stability of the obtained results under slight variations of the assumed inputs. We perform several determinations, using different methodologies, and find a very consistent set of results. All determinations are in excellent agreement, and allow us to extract a very reliable value for alpha(s)(m(tau)(2)). The main uncertainty originates in the pure perturbative error from unknown higher orders. Taking into account the systematic differences between the results obtained with the contour-improved perturbation theory and fixed-order perturbation theory prescriptions, we find alpha((nf=3))(s) (m(tau)(2)) = 0.328 +/- 0.013 which implies alpha((nf=5))(s) (M-Z(2)) = 0.1197 +/- 0.0015. |
Address |
[Pich, Antonio; Rodriguez-Sanchez, Antonio] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Apartat Correus 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 |
2470-0010 |
ISBN |
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Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000381413500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2795 |
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 |
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 |
|
ISSN |
0217-7323 |
ISBN |
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Medium |
|
Area |
|
Expedition |
|
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 |
Pich, A.; Rosell, I.; Santos, J.; Sanz-Cillero, J.J. |
Title |
Fingerprints of heavy scales in electroweak effective Lagrangians |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
04 |
Issue |
4 |
Pages |
012 - 60pp |
Keywords |
Beyond Standard Model; Chiral Lagrangians; Higgs Physics; Technicolor and Composite Models |
Abstract |
The couplings of the electroweak effective theory contain information on the heavy-mass scales which are no-longer present in the low-energy Lagrangian. We build a general effective Lagrangian, implementing the electroweak chiral symmetry breaking SU(2)(L) circle times SU(2)(R) -> SU(2)(L+R), which couples the known particle fields to heavier states with bosonic quantum numbers J(P) = 0(+/-) and 1(+/-). We consider colour-singlet heavy fields that are in singlet or triplet representations of the electroweak group. Integrating out these heavy scales, we analyze the pattern of low-energy couplings among the light fields which are generated by the massive states. We adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs, without making any assumption about its possible doublet structure. Special attention is given to the different possible descriptions of massive spin-1 fields and the differences arising from naive implementations of these formalisms, showing their full equivalence once a proper short-distance behaviour is required. |
Address |
[Pich, Antonio; Santos, Joaquin] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Apt Correus 22085, E-46071 Valencia, Spain, Email: 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 |
1029-8479 |
ISBN |
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Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000398449400004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3074 |
Permanent link to this record |
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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 |
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 |
|
Area |
|
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 |
Peñuelas, A.; Pich, A. |
Title |
Flavour alignment in multi-Higgs-doublet models |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
12 |
Issue |
12 |
Pages |
084 - 34pp |
Keywords |
Beyond Standard Model; Higgs Physics |
Abstract |
Extended electroweak scalar sectors containing several doublet multiplets require flavour-aligned Yukawa matrices to prevent the appearance at tree level of unwanted flavour-changing neutral-current transitions. We analyse the misalignment induced by one-loop quantum corrections and explore possible generalizations of the alignment condition and their compatibility with current experimental constraints. The hypothesis of flavour alignment at a high scale turns out to be consistent with all known phenomenological tests. |
Address |
[Penuelas, Ana; Pich, Antonio] Univ Valencia, CSIC, Dept Fis Teor, IFIC, Apt Correus 22085, E-46071 Valencia, Spain, Email: Ana.Penuelas@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 |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
|
Conference |
|
Notes |
WOS:000418371800004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3423 |
Permanent link to this record |
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Author |
Gisbert, H.; Pich, A. |
Title |
Direct CP violation in K-0 -> pi pi : Standard Model Status |
Type |
Journal Article |
Year |
2018 |
Publication |
Reports on Progress in Physics |
Abbreviated Journal |
Rep. Prog. Phys. |
Volume |
81 |
Issue |
7 |
Pages |
076201 - 22pp |
Keywords |
Kaon decays; CP violation; Standard Model |
Abstract |
In 1988 the NA31 experiment presented the first evidence of direct CP violation in the K-0 -> pi pi decay amplitudes. A clear signal with a 7.2 sigma statistical significance was later established with the full data samples from the NA31, E731, NA48 and KTeV experiments, confirming that CP violation is associated with a Delta S = 1 quark transition, as predicted by the Standard Model. However, the theoretical prediction for the measured ratio epsilon'/epsilon has been a subject of strong controversy along the years. Although the underlying physics was already clarified in 2001, the recent release of improved lattice data has revived again the theoretical debate. We review the current status, discussing in detail the different ingredients that enter into the calculation of this observable and the reasons why seemingly contradictory predictions were obtained in the past by several groups. An update of the Standard Model prediction is presented and the prospects for future improvements are analysed. Taking into account all known short-distance and long-distance contributions, one obtains Re (epsilon' / epsilon) = (15 +/- 7) . 10(-4), in good agreement with the experimental measurement. |
Address |
[Gisbert, Hector; Pich, Antonio] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Apt Correus 22085, E-46071 Valencia, Spain, Email: Antonio.Pich@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing 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 |
0034-4885 |
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:000436545600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3641 |
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 |
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 |
|
Area |
|
Expedition |
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Conference |
|
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 |
Celis, A.; Jung, M.; Li, X.Q.; Pich, A. |
Title |
Sensitivity to charged scalars in B -> D-(*)tau nu(tau) and B -> tau nu(tau) decays |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
054 - 27pp |
Keywords |
Beyond Standard Model; B-Physics |
Abstract |
We analyze the recent experimental evidence for an excess of tau-lepton production in several exclusive semileptonic B-meson decays in the context of two-Higgs-doublet models. These decay modes are sensitive to the exchange of charged scalars and constrain strongly their Yukawa interactions. While the usual Type-II scenario cannot accommodate the recent BaBar data, this is possible within more general models in which the charged-scalar couplings to up-type quarks are not as suppressed. Both the B -> D-(*)tau nu(tau) and the B -> tau nu(tau) data can be fitted within the framework of the Aligned Two-Higgs-Doublet Model, but the resulting parameter ranges are in conflict with the constraints from leptonic charm decays. This could indicate a departure from the family universality of the Yukawa couplings, beyond their characteristic fermion mass dependence. We discuss several new observables that are sensitive to a hypothetical charged-scalar contribution, demonstrating that they are well suited to distinguish between different scenarios of new physics in the scalar sector, and also between this group and models with different Dirac structures; their experimental study would therefore shed light on the relevance of scalar exchanges in semileptonic b -> c tau(-)(nu) over bar (tau) transitions. |
Address |
[Celis, Alejandro; Li, Xin-Qiang; Pich, Antonio] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: alejandro.celis@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 |
|
Notes |
WOS:000315583200054 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1368 |
Permanent link to this record |
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Author |
Li, X.Q.; Lu, J.; Pich, A. |
Title |
Bs,d(0) -> l(+)l(-) decays in the aligned two-Higgs-doublet model |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
06 |
Issue |
6 |
Pages |
022 - 39pp |
Keywords |
Higgs Physics; Rare Decays; Beyond Standard Model; B-Physics |
Abstract |
The rare decays B-s,d(0) -> l(+)l(-) are analyzed within the general framework of the aligned two-Higgs doublet model. We present a complete one-loop calculation of the relevant short-distance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We investigate the impact of various model parameters on the branching ratios and study the phenomenological constraints imposed by present data. |
Address |
[Li, Xin-Qiang] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China, Email: xqli@itp.ac.cn; |
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 |
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:000338520600002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1855 |
Permanent link to this record |
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Author |
Ilisie, V.; Pich, A. |
Title |
Low-mass fermiophobic charged Higgs phenomenology in two-Higgs-doublet models |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
09 |
Issue |
9 |
Pages |
089 - 32pp |
Keywords |
Higgs Physics; Beyond Standard Model |
Abstract |
After the recent discovery of a Higgs-like boson, the possibility of an enlarged scalar sector arises as a natural question. Experimental searches for charged scalars have been already performed with negative results. We analyze the phenomenology associated with a fermiophobic charged Higgs (it does not couple to fermions at tree level), in two-Higgs-doublet models. All present experimental bounds are evaded trivially in this case, and one needs to consider other decay and production channels. We study the associated production of a charged Higgs with either a W or a neutral scalar boson, and the relevant decays for a light fermiophobic charged Higgs. The interesting features of this scenario should result encouraging for the LHC collaborations to perform searches for such a particle. |
Address |
[Ilisie, Victor; Pich, Antonio] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: ilisiev@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 |
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:000342430800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1953 |
Permanent link to this record |