| Records |
| Author |
Borexino Collaboration (Bellini, G. et al); Pena-Garay, C. |
| Title |
Absence of a day-night asymmetry in the Be-7 solar neutrino rate in Borexino |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
707 |
Issue |
1 |
Pages |
22-26 |
| Keywords |
Solar neutrinos; Day-night effect; CPT violation; Neutrino oscillations |
| Abstract |
We report the result of a search for a day-night asymmetry in the Be-7 solar neutrino interaction rate in the Borexino detector at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The measured asymmetry is A(dn) = 0.001 +/- 0.012 (stat) +/- 0.007 (syst), in agreement with the prediction of MSW-LMA solution for neutrino oscillations. This result disfavors MSW oscillations with mixing parameters in the LOW region at more than 8.5 sigma. This region is, for the first time, strongly disfavored without the use of reactor anti-neutrino data and therefore the assumption of CPT symmetry. The result can also be used to constrain some neutrino oscillation scenarios involving new physics. |
| Address |
[Carraro, C.; Davini, S.; Guardincerri, E.; Manuzio, G.; Pallavicini, M.; Perasso, S.; Salvo, C.; Testera, G.; Zavatarelli, S.] Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy, Email: marco.pallavicini@ge.infn.it |
| 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 |
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Conference |
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Notes  |
WOS:000299757000004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
901 |
| Permanent link to this record |
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| Author |
de Adelhart Toorop, R.; Bazzocchi, F.; Morisi, S. |
| Title |
Quark mixing in the discrete dark matter model |
Type |
Journal Article |
| Year |
2012 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
| Volume |
856 |
Issue |
3 |
Pages |
670-681 |
| Keywords |
Discrete flavour symmetries; Dark matter; Meson oscillations |
| Abstract |
We consider a model in which dark matter is stable as it is charged under a Z(2) symmetry that is residual after an A(4) flavour symmetry is broken. We consider the possibility to generate the quark masses by charging the quarks appropriately under A(4). We find that it is possible to generate the CKM mixing matrix by an interplay of renormalisable and dimension-six operators. In this set-up, we predict the third neutrino mixing angle to be large and the dark matter relic density to be in the correct range. Low energy observables – in particular meson-antimeson oscillations – are hard to facilitate. We find that only in a situation where there is a strong cancellation between the Standard Model contribution and the contribution of the new Higgs fields, B meson oscillations are under control. |
| Address |
[Toorop, Reinier de Adelhart] Nikhef Theory Grp, NL-1098 XG Amsterdam, Netherlands, Email: reintoorop@nikhef.nl |
| 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 |
0550-3213 |
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:000300028200003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
891 |
| Permanent link to this record |
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| Author |
Blankenburg, G.; Morisi, S. |
| Title |
Fermion masses and mixing with tri-bimaximal in SO(10) with type-I seesaw |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
01 |
Issue |
1 |
Pages |
016 - 18pp |
| Keywords |
Neutrino Physics; GUT |
| Abstract |
We study a class of models for tri-bimaximal neutrino mixing in SO(10) grand unified SUSY framework. Neutrino masses arise from both type-I and type-II seesaw mechanisms. We use dimension five operators in order to not spoil tri-bimaximal mixing by means of type-I contribution in the neutrino sector. We show that it is possible to fit all fermion masses and mixings including also the recent T2K result as deviation from the tri-bimaximal. |
| Address |
[Blankenburg, G.] Univ Roma Tre, Dipartimento Fis E Amaldi, I-00146 Rome, Italy, Email: blankenburg@fis.uniroma3.it |
| 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:000300181800016 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
970 |
| Permanent link to this record |
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| Author |
Aguilar, A.C.; Binosi, D.; Papavassiliou, J. |
| Title |
Gluon mass through ghost synergy |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
01 |
Issue |
1 |
Pages |
050 - 32pp |
| Keywords |
Nonperturbative Effects; QCD |
| Abstract |
In this work we compute, at the “one-loop-dressed” level, the nonperturbative contribution of the ghost loops to the self-energy of the gluon propagator, in the Landau gauge. This is accomplished within the PT-BFM formalism, where the contribution of the ghost-loops is inherently transverse, by virtue of the QED-like Ward identities satisfied in this framework. At the level of the “one-loop dressed” approximation, the ghost transversality is preserved by employing a suitable gauge-technique Ansatz for the longitudinal part of the full ghost-gluon vertex. Under the key assumption that the undetermined transverse part of this vertex is numerically subleading in the infrared, and using as nonperturbative input the available lattice data for the ghost dressing function, we show that the ghost contributions have a rather sizable effect on the overall shape of the gluon propagator, both for d = 3, 4. Then, by exploiting a recently introduced dynamical equation for the effective gluon mass, whose solutions depend crucially on the characteristics of the gluon propagator at intermediate energies, we show that if the ghost loops are removed from the gluon propagator then the gluon mass vanishes. These findings suggest that, at least at the level of the Schwinger-Dyson equations, the effects of gluons and ghosts are inextricably connected, and must be combined suitably in order to reproduce the results obtained in the recent lattice simulations. |
| Address |
[Aguilar, A. C.] Fed Univ ABC, CCNH, BR-09210170 Santo Andre, Brazil, Email: arlene.aguilar@ufabc.edu.br |
| 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:000300181800050 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
969 |
| Permanent link to this record |
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| Author |
Kuhn, J.H.; Rodrigo, G. |
| Title |
Charge asymmetries of top quarks at hadron colliders revisited |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
01 |
Issue |
1 |
Pages |
063 - 25pp |
| Keywords |
Heavy Quark Physics; Hadronic Colliders; Standard Model; Beyond Standard Model |
| Abstract |
A sizeable difference in the differential production cross section of top-compared to antitop-quark production, denoted charge asymittetm has been observed at the Tevatron. The experimental results seem to exceed the theory predictions based on the Standard Model by a significant amount and have triggered a large number of suggestions for “new physics'. In the present paper the Standard Model predictions for Tevatron and LHe experiments are revisited. This includes a reanalysis of electromagnetic as well as weak corrections, leading to a shift of the asymmetry by roughly a factor 1.1 when compared to the results of the first papers on this subject. The impact of cuts on the transverse momentum of the top-antitop system is studied. Restricting the it system to a transverse momentum less than 20 GeV leads to an enhancement of the asymmetries by factors between 1.3 and 1.5, indicating the importance of an improved understanding of the tt-momentum distribution. Predictions for similar measurements at the LHC are presented, demonstrating the sensitivity of the large rapidity region bot ti to the Standard Model contribution and effects from ”new physics". |
| Address |
[Kuehn, Johann H.] Karlsruher Inst Technol, Inst Theoret Teilchenphys, D-76133 Karlsruhe, Germany, Email: johann.kuehn@kit.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 |
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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:000300181800063 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
971 |
| Permanent link to this record |
