Records |
Author |
Bossingham, T.; Mavromatos, N.E.; Sarkar, S. |
Title |
Leptogenesis from heavy right-handed neutrinos in CPT violating backgrounds |
Type |
Journal Article |
Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
78 |
Issue |
2 |
Pages |
113 - 33pp |
Keywords |
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Abstract |
We discuss leptogenesis in a model with heavy right-handed Majorana neutrinos propagating in a constant but otherwise generic CPT-violating axial time-like background (motivated by string theory). At temperatures much higher than the temperature of the electroweak phase transition, we solve approximately, but analytically (using Pade approximants), the corresponding Boltzmann equations, which describe the generation of lepton asymmetry from the tree-level decays of heavy neutrinos into Standard Model leptons. At such temperatures these leptons are effectively massless. The current work completes in a rigorous way a preliminary treatment of the same system, by some of the present authors. In this earlier work, lepton asymmetry was crudely estimated considering the decay of a righthanded neutrino at rest. Our present analysis includes thermal momentum modes for the heavy neutrino and this leads to a total lepton asymmetry which is bigger by a factor of two as compared to the previous estimate. Nevertheless, our current and preliminary results for the freezeout are found to be in agreement (within a similar to 12.5% uncertainty). Our analysis depends on a novel use of Pade approximants to solve the Boltzmann equations and may be more widely useful in cosmology. |
Address |
[Bossingham, Thomas; Mavromatos, Nick E.; Sarkar, Sarben] Kings Coll London, Dept Phys, Theoret Particle Phys & Cosmol Grp, London WC2R 2LS, England, Email: Nikolaos.Mavromatos@cern.ch |
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Springer |
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
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English |
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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:000424657600002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3486 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Higon-Rodriguez, E.; Jimenez Pena, J.; Lacasta, C.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Mitsou, V.A.; Pedraza Lopez, S.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Romero Adam, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Direct top-quark decay width measurement in the t(t)over-bar lepton+jets channel at root s=8 TeV with the ATLAS experiment |
Type |
Journal Article |
Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
78 |
Issue |
2 |
Pages |
129 - 30pp |
Keywords |
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Abstract |
This paper presents a direct measurement of the decay width of the top quark using t (t) over bar events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in proton-proton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb(-1). The decay width of the top quark is measured using a template fit to distributions of kinematic observables associated with the hadronically and semileptonically decaying top quarks. The result, Gamma(t) = 1.76 +/- 0.33 (stat.) (+0.79)(-0.68) (syst.) GeV for a top-quark mass of 172.5 GeV, is consistent with the prediction of the Standard Model. |
Address |
[Chelkov, G. A.; Duvnjak, D.; Jackson, P.; Petridis, A.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia, Email: atlas.publications@cern.ch |
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Thesis |
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Publisher |
Springer |
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
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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:000425393800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3492 |
Permanent link to this record |
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Author |
Boronat, M.; Fuster, J.; Garcia, I.; Roloff, P.; Simoniello, R.; Vos, M. |
Title |
Jet reconstruction at high-energy electron-positron colliders |
Type |
Journal Article |
Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
78 |
Issue |
2 |
Pages |
144 - 16pp |
Keywords |
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Abstract |
In this paper we study the performance in e(+)e(-) collisions of classical e(+)e(-) jet reconstruction algorithms, longitudinally invariant algorithms and the recently proposed Valencia algorithm. The study includes a comparison of perturbative and non-perturbative jet energy corrections and the response under realistic background conditions. Several algorithms are benchmarked with a detailed detector simulation at root s = 3 TeV. We find that the classical e(+)e(-) algorithms, with or without beam jets, have the best response, but they are inadequate in environments with non-negligible background. The Valencia algorithm and longitudinally invariant k(t) algorithms have a much more robust performance, with a slight advantage for the former. |
Address |
[Boronat, M.; Fuster, J.; Garcia, I.; Vos, M.] IFIC CSIC UVEG, Valencia, Spain, Email: ignacio.garcia@ific.uv.es |
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Thesis |
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Publisher |
Springer |
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
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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:000425658000002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3495 |
Permanent link to this record |
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Author |
ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Higon-Rodriguez, E.; Jimenez Pena, J.; Lacasta, C.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Mitsou, V.A.; Pedraza Lopez, S.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Romero Adam, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Measurement of longitudinal flow decorrelations in Pb plus Pb collisions at root s(NN)=2.76 and 5.02 TeV with the ATLAS detector |
Type |
Journal Article |
Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
78 |
Issue |
2 |
Pages |
142 - 37pp |
Keywords |
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Abstract |
Measurements of longitudinal flow correlations are presented for charged particles in the pseudorapidity range vertical bar eta vertical bar < 2.4 using 7 μb(-1) and 470 μb(-1) of Pb+Pb collisions at root s(NN) = 2.76 and 5.02 TeV, respectively, recorded by the ATLAS detector at the LHC. It is found that the correlation between the harmonic flow coefficients v(n) measured in two separated eta intervals does not factorise into the product of single-particle coefficients, and this breaking of factorisation, or flow decorrelation, increases linearly with the eta separation between the intervals. The flow decorrelation is stronger at 2.76 TeVthan at 5.02 TeV. Higher-order moments of the correlations are also measured, and the corresponding linear coefficients for the kth-moment of the v(n) are found to be proportional to k for v(3), but not for v(2). The decorrelation effect is separated into contributions from the magnitude of v(n) and the event-plane orientation, each as a function of eta. These two contributions are found to be comparable. The longitudinal flow correlations are also measured between v(n) of different order in n. The decorrelations of v(2) and v(3) are found to be independent of each other, while the decorrelations of v(4) and v(5) are found to be driven by the nonlinear contribution from v(2)(2) and v(2)v(3), respectively. |
Address |
[Aleksa, M.; Gonzalez, B. Alvarez; Amoroso, S.; Armbruster, A. J.; Avolio, G.; Barisits, M. -S.; Beermann, T. A.; Bella, G.; Beltramello, O.; Bortfeldt, J.; Boyd, J.; Butti, P.; Camarda, S.; Campana, S.; Garrido, M. D. M. Capeans; Carli, T.; Carrillo-Montoya, G. D.; Catinaccio, A.; Cattai, A.; Chelstowska, M. A.; Chisholm, A. S.; Conti, G.; Cortes-Gonzalez, A.; Czodrowski, P.; Dell'Acqua, A.; Deviveiros, P. O.; Di Girolamo, A.; Di Girolamo, B.; Di Nardo, R.; Dittus, F.; Dobos, D.; Dudarev, A.; Duhrssen, M.; Eifert, T.; Ellis, N.; Elsing, M.; Faltova, J.; Farthouat, P.; Fassnacht, P.; Feng, E. J.; Francis, D.; Fressard-Batraneanu, S. M.; Froidevaux, D.; Gadatsch, S.; Goossens, L.; Gorini, B.; Guenther, J.; Guindon, S.; Gumpert, C.; Hawkings, R. J.; Helary, L.; Helsens, C.; Correia, A. M. Henriques; Hervas, L.; Hoecker, A.; Hrdinka, J.; Huhtinen, M.; Iengo, P.; Klioutchnikova, T.; Krasznahorkay, A.; Kuehn, S.; Langenberg, R. J.; Lassnig, M.; Miotto, G. Lehmann; Lenzi, B.; Malyukov, S.; Manousos, A.; Mapelli, L.; Tobon, C. A. Marin; Marzin, A.; Mcfayden, J. A.; Berlingen, J. Montejo; Llacer, M. Moreno; Morgenstern, S.; Morley, A. K.; Mornacchi, G.; Musheghyan, H.; Nairz, A. M.; Nessi, M.; Nordberg, M.; Palestini, S.; Pani, P.; Pauly, T.; Pernegger, H.; Petersen, B. A.; Polifka, R.; Pommes, K.; Astigarraga, M. E. Pozo; Raymond, M.; Rembser, C.; Ristic, B.; Ritsch, E.; Roe, S.; Ruthmann, N.; Salzburger, A.; Schaepe, S.; Schlenker, S.; Schmieden, K.; Schovancova, J.; Sanchez, C. A. Solans; Spigo, G.; Starz, S.; Stelzer, H. J.; Ten Kate, H.; Unal, G.; Vandelli, W.; Venturi, N.; Voss, R.; Vuillermet, R.; Wells, P. S.; Wengler, T.; Wenig, S.; Werner, P.; Wilkens, H. G.; Wotschack, J.; Young, C. J. S.; Zwalinski, L.] CERN, CH-1211 Geneva, Switzerland |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
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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:000425395800005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3496 |
Permanent link to this record |
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Author |
Bernreuther, W.; Chen, L.; Garcia, I.; Perello, M.; Poeschl, R.; Richard, F.; Ros, E.; Vos, M. |
Title |
CP-violating top quark couplings at future linear e+e- colliders |
Type |
Journal Article |
Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
78 |
Issue |
2 |
Pages |
155 - 21pp |
Keywords |
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Abstract |
We study the potential of future lepton colliders to probe violation of the CP symmetry in the top quark sector. In certain extensions of the Standard Model, such as the two-Higgs-doublet model (2HDM), sizeable anomalous top quark dipole moments can arise, which may be revealed by a precise measurement of top quark pair production. We present results from detailed Monte Carlo studies for the ILC at 500 GeV and CLIC at 380 GeV and use parton-level simulations to explore the potential of high-energy operation. We find that precise measurements in e(+)e(-) -> t (t) over bar production with subsequent decay to lepton plus jets final states can provide sufficient sensitivity to detect Higgs-boson-induced CP violation in a viable two-Higgs-doublet model. The potential of a linear e(+)e(-) collider to detect CP-violating electric and weak dipole form factors of the top quark exceeds the prospects of the HL-LHC by over an order of magnitude. |
Address |
[Bernreuther, W.; Chen, L.] Rhein Westfal TH Aachen, Inst Theoret Teilchenphys & Kosmol, D-52056 Aachen, Germany, Email: ignacio.garcia@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
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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:000426403400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3503 |
Permanent link to this record |