Records |
Author |
Jantzen, B.; Ruiz-Femenia, P. |
Title |
Next-to-next-to-leading order nonresonant corrections to threshold top-pair production from e(+)e(-) collisions: Endpoint-singular terms |
Type |
Journal Article |
Year |
2013 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
88 |
Issue |
5 |
Pages |
054011 - 20pp |
Keywords |
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Abstract |
We analyze the subleading nonresonant contributions to the e(+)e(-) -> W(+)W(-)b (b) over bar cross section at energies near the top-antitop threshold. These correspond to next-to-next-to-leading-order (NNLO) corrections with respect to the leading-order resonant result. We show that these corrections produce 1/epsilon endpoint singularities which precisely cancel the finite-width divergences arising in the resonant production of the W(+)W(-)b (b) over bar final state from on-shell decays of the top and antitop quarks at the same order. We also provide analytic results for the (m(t)/Lambda)(2), (m(t)/Lambda) and (m(t)/Lambda)(0) log Lambda terms that dominate the expansion in powers of (Lambda/m(t)) of the complete set of NNLO nonresonant corrections, where Lambda is a cut imposed on the invariant masses of the bW pairs that is neither too tight nor too loose (m(t)Gamma(t) << Lambda(2) << m(t)(2)). |
Address |
[Jantzen, B.] Rhein Westfal TH Aachen, Inst Theoret Teilchenphys & Kosmol, D-52056 Aachen, Germany, Email: ruiz@ific.uv.es |
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 |
1550-7998 |
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:000324232700007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1581 |
Permanent link to this record |
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Author |
Amjad, M.S.; Bilokin, S.; Boronat, M.; Doublet, P.; Frisson, T.; Garcia Garcia, I.; Perello, M.; Poschl, R.; Richard, F.; Ros, E.; Rouene, J.; Ruiz-Femenia, P.; Vos, M. |
Title |
A precise characterisation of the top quark electro-weak vertices at the ILC |
Type |
Journal Article |
Year |
2015 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
75 |
Issue |
10 |
Pages |
512 - 11pp |
Keywords |
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Abstract |
Top quark production in the process e(+)e(-) -> t t at a future linear electron positron collider with polarised beams is a powerful tool to determine indirectly the scale of new physics. The presented study, based on a detailed simulation of the ILD detector concept, assumes a centre-of-mass energy of root s = 500GeV and a luminosity of L = 500 fb(-1) equally shared between the incoming beam polarisations of Pe-, Pe+ = +/- 0.8, -/+ 0.3. Events are selected in which the top pair decays semi-leptonically and the cross sections and the forward-backward asymmetries are determined. Based on these results, the vector, axial vector and tensorial CP conserving couplings are extracted separately for the photon and the Z(0) component. With the expected precision, a large number of models in which the top quark acts as a messenger to new physics can be distinguished with many standard deviations. This will dramatically improve expectations from e.g. the LHC for electro-weak couplings of the top quark. |
Address |
[Amjad, M. S.; Bilokin, S.; Frisson, T.; Poschl, R.; Richard, F.; Rouene, J.] Ctr Sci Orsay, LAL, BP 34,Batiment 200, F-91898 Orsay, France, Email: poeschl@lal.in2p3.fr |
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 |
1434-6044 |
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:000379515400003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2766 |
Permanent link to this record |
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Author |
Hellmann, C.; Ruiz-Femenia, P. |
Title |
Non-relativistic pair annihilation of nearly mass degenerate neutralinos and charginos II. P-wave and next-to-next-to-leading order S-wave coefficients |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
084 - 49pp |
Keywords |
Cosmology of Theories beyond the SM; Supersymmetric Standard Model; Nonperturbative Effects |
Abstract |
This paper is a continuation of an earlier work (arXiv:1210.7928) which computed analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM. Here we extend the results by providing the next-to-next-to-leading order corrections to the rates in the non-relativistic expansion in momenta and mass differences, which include leading P-wave effects, in analytic form. The results are a necessary input for the calculation of the Sommerfeld-enhanced dark matter annihilation rates including short-distance corrections at next-to-next-to-leading order in the non-relativistic expansion in the general MSSM with neutralino LSP. |
Address |
[Hellmann, C.] Tech Univ Munich, Phys Dept T31, D-85748 Garching, Germany, Email: charlotte.hellmann@tum.de; |
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:000324113700084 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1594 |
Permanent link to this record |
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Author |
Beneke, M.; Hellmann, C.; Ruiz-Femenia, P. |
Title |
Non-relativistic pair annihilation of nearly mass degenerate neutralinos and charginos III. Computation of the Sommerfeld enhancements |
Type |
Journal Article |
Year |
2015 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
115 - 57pp |
Keywords |
Cosmology of Theories beyond the SM; Supersymmetric Standard Model; Nonperturbative Effects |
Abstract |
This paper concludes the presentation of the non-relativistic effective field theory formalism designed to calculate the radiative corrections that enhance the pair-annihilation cross sections of slowly moving neutralinos and charginos within the general minimal supersymmetric standard model (MSSM). While papers I and II focused on the computation of the tree-level annihilation rates that feed into the short-distance part, here we describe in detail the method to obtain the Sommerfeld factors that contain the enhanced long-distance corrections. This includes the computation of the potential interactions in the MSSM, which are provided in compact analytic form, and a novel solution of the multi-state Schrodinger equation that is free from the numerical instabilities generated by large mass splittings between the scattering states. Our results allow for a precise computation of the MSSM neutralino dark matter relic abundance and pair-annihilation rates in the present Universe, when Sommerfeld enhancements are important. |
Address |
[Beneke, M.; Hellmann, C.] Tech Univ Munich, Phys Dept T31, D-85748 Garching, Germany, Email: charlotte.hellmann@tum.de; |
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:000354959300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2235 |
Permanent link to this record |
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Author |
Fuentes-Martin, J.; Portoles, J.; Ruiz-Femenia, P. |
Title |
Instanton-mediated baryon number violation in non-universal gauge extended models |
Type |
Journal Article |
Year |
2015 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
134 - 34pp |
Keywords |
Beyond Standard Model; Solitons Monopoles and Instantons; Effective field theories; Global Symmetries |
Abstract |
Instanton solutions of non-abelian Yang-Mills theories generate an effective action that may induce lepton and baryon number violations, namely Delta B = Delta L = nf, being nf the number of families coupled to the gauge group. In this article we study instanton mediated processes in a SU( 2)(l)circle times SU(2)(h)circle times U(1) extension of the Standard Model that breaks universality by singularizing the third family. In the construction of the instanton Green functions we account systematically for the inter-family mixing. This allows us to use the experimental bounds on proton decay in order to constrain the gauge coupling of SU(2)(h). Tau lepton non-leptonic and radiative decays with Delta B = Delta L = 1 are also analysed. |
Address |
[Fuentes-Martin, J.; Portoles, J.; Ruiz-Femenia, P.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: Javier.Fuentes@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:000363463300002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2429 |
Permanent link to this record |