| Records |
| Author |
Beltran, R.; Cottin, G.; Helo, J.C.; Hirsch, M.; Titov, A.; Wang, Z.S. |
| Title |
Long-lived heavy neutral leptons at the LHC: four-fermion single-N-R operators |
Type |
Journal Article |
| Year |
2022 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
01 |
Issue  |
1 |
Pages |
044 - 18pp |
| Keywords |
Beyond Standard Model; Effective Field Theories; Neutrino Physics |
| Abstract |
Interest in searches for heavy neutral leptons (HNLs) at the LHC has increased considerably in the past few years. In the minimal scenario, HNLs are produced and decay via their mixing with active neutrinos in the Standard Model (SM) spectrum. However, many SM extensions with HNLs have been discussed in the literature, which sometimes change expectations for LHC sensitivities drastically. In the N-R SMEFT, one extends the SM effective field theory with operators including SM singlet fermions, which allows to study HNL phenomenology in a “model independent” way. In this paper, we study the sensitivity of ATLAS to HNLs in the N-R SMEFT for four-fermion operators with a single HNL. These operators might dominate both production and decay of HNLs, and we find that new physics scales in excess of 20 TeV could be probed at the high-luminosity LHC. |
| Address |
[Beltran, Rebeca; Hirsch, Martin] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Apartado 22085, E-46071 Valencia, Spain, Email: rebeca.beltran@ifis.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:000742012500001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5079 |
| Permanent link to this record |
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| Author |
Escribano, P.; Hirsch, M.; Nava, J.; Vicente, A. |
| Title |
Observable flavor violation from spontaneous lepton number breaking |
Type |
Journal Article |
| Year |
2022 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
01 |
Issue |
1 |
Pages |
098 - 31pp |
| Keywords |
Beyond Standard Model; Neutrino Physics; Global Symmetries |
| Abstract |
We propose a simple model of spontaneous lepton number violation with potentially large flavor violating decays, including the possibility that majoron emitting decays, such as μ-> e J, saturate the experimental bounds. In this model the majoron is a singlet-doublet admixture. It generates a type-I seesaw for neutrino masses and contains also a vector-like lepton. As a by-product, the model can explain the anomalous (g – 2)(mu), in parts of its parameter space, where one expects that the branching ratio of the Higgs to muons is changed with respect to Standard Model expectations. However, the explanation of the muon g – 2 anomaly would lead to tension with recent astrophysical bounds on the majoron coupling to muons. |
| Address |
[Escribano, Pablo; Hirsch, Martin; Nava, Jacopo; Vicente, Avelino] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cient Paterna,C Catedrcit Jose Beltrcin 2, E-46980 Valencia, Spain, Email: pablo.escribano@ifis.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:000744514600003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
5084 |
| Permanent link to this record |
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| Author |
Beltran, R.; Cottin, G.; Helo, J.C.; Hirsch, M.; Titov, A.; Wang, Z.S. |
| Title |
Long-lived heavy neutral leptons from mesons in effective field theory |
Type |
Journal Article |
| Year |
2023 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
01 |
Issue |
1 |
Pages |
015 - 38pp |
| Keywords |
New Light Particles; SMEFT; Sterile or Heavy Neutrinos |
| Abstract |
In the framework of the low-energy effective field theory of the Standard Model extended with heavy neutral leptons (HNLs), we calculate the production rates of HNLs from meson decays triggered by dimension-six operators. We consider both lepton number-conserving and lepton-number-violating four-fermion operators involving either a pair of HNLs or a single HNL. Assuming that HNLs are long-lived, we perform simulations and investigate the reach of the proposed far detectors at the high-luminosity LHC to (i) active-heavy neutrino mixing and (ii) the Wilson coefficients associated with the effective operators, for HNL masses below the mass of the B-meson. We further convert the latter to the associated new-physics scales. Our results show that scales in excess of hundreds of TeV and the active-heavy mixing squared as small as 10(-15 )can be probed by these experiments. |
| Address |
[Beltran, Rebeca; Hirsch, Martin] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Apartado 22085, E-46071 Valencia, Spain, Email: rebeca.beltran@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:000909520000005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5455 |
| Permanent link to this record |
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| Author |
Hirsch, M.; Srivastava, R.; Valle, J.W.F. |
| Title |
Can one ever prove that neutrinos are Dirac particles? |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
781 |
Issue |
|
Pages |
302-305 |
| Keywords |
|
| Abstract |
According to the “Black Box” theorem the experimental confirmation of neutrinoless double beta decay (0 nu 2 beta) would imply that at least one of the neutrinos is a Majorana particle. However, a null 0 nu 2 beta signal cannot decide the nature of neutrinos, as it can be suppressed even for Majorana neutrinos. In this letter we argue that if the null 0 nu 2 beta decay signal is accompanied by a 0 nu 2 beta quadruple beta decay signal, then at least one neutrino should be a Dirac particle. This argument holds irrespective of the underlying processes leading to such decays. |
| Address |
[Hirsch, Martin; Srivastava, Rahul; Valle, Jose W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, C Catedrat Jose Beltran 2, E-46980 Valencia, Spain, Email: mahirsch@ific.uv.es; |
| 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:000435653100039 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
3632 |
| Permanent link to this record |
