| Records |
| Author |
Aparici, A.; Herrero-Garcia, J.; Rius, N.; Santamaria, A. |
| Title |
On the nature of the fourth generation neutrino and its implications |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
07 |
Issue |
7 |
Pages |
030 - 31pp |
| Keywords |
Beyond Standard Model; Neutrino Physics |
| Abstract |
We consider the neutrino sector of a Standard Model with four generations. While the three light neutrinos can obtain their masses from a variety of mechanisms with or without new neutral fermions, fourth-generation neutrinos need at least one new relatively light right-handed neutrino. If lepton number is not conserved this neutrino must have a Majorana mass term whose size depends on the underlying mechanism for lepton number violation. Majorana masses for the fourth-generation neutrinos induce relative large two-loop contributions to the light neutrino masses which could be even larger than the cosmological bounds. This sets strong limits on the mass parameters and mixings of the fourth-generation neutrinos. |
| Address |
[Aparici, Alberto] Univ Valencia, CSIC, Dept Fis Teor, Valencia 46071, Spain, Email: alberto.aparici@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 |
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| Notes |
WOS:000307298400030 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
1157 |
| Permanent link to this record |
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| Author |
Aplin, S.; Boronat, M.; Dannheim, D.; Duarte, J.; Gaede, F.; Ruiz-Jimeno, A.; Sailer, A.; Valentan, M.; Vila, I.; Vos, M. |
| Title |
Forward tracking at the next e(+)e(-) collider part II: experimental challenges and detector design |
Type |
Journal Article |
| Year |
2013 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
8 |
Issue |
|
Pages |
T06001 - 26pp |
| Keywords |
Particle tracking detectors; Large detector systems for particle and astroparticle physics; Particle tracking detectors (Solid-state detectors) |
| Abstract |
We present the second in a series of studies into the forward tracking system for a future linear e(+)e(-) collider with a center-of-mass energy in the range from 250 GeV to 3 TeV. In this note a number of specific challenges are investigated, which have caused a degradation of the tracking and vertexing performance in the forward region in previous experiments. We perform a quantitative analysis of the dependence of the tracking performance on detector design parameters and identify several ways to mitigate the performance loss for charged particles emitted at shallow angle. |
| Address |
[Aplin, S.; Gaede, F.] Deutsche Elektronen Synchrotron, D-22607 Hamburg, Germany |
| 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 |
1748-0221 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000321627400024 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1503 |
| Permanent link to this record |
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| Author |
Arbelaez, C.; Carcamo Hernandez, A.E.; Cepedello, R.; Kovalenko, S.; Schmidt, I. |
| Title |
Sequentially loop suppressed fermion masses from a single discrete symmetry |
Type |
Journal Article |
| Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
06 |
Issue |
6 |
Pages |
043 - 24pp |
| Keywords |
Beyond Standard Model; Neutrino Physics; Quark Masses and SM Parameters |
| Abstract |
We propose a systematic and renormalizable sequential loop suppression mechanism to generate the hierarchy of the Standard Model fermion masses from one discrete symmetry. The discrete symmetry is sequentially softly broken in order to generate one-loop level masses for the bottom, charm, tau and muon leptons and two-loop level masses for the lightest Standard Model charged fermions. The tiny masses for the light active neutrinos are produced from radiative type-I seesaw mechanism, where the Dirac mass terms are effectively generated at two-loop level. |
| Address |
[Arbelaez, Carolina; Carcamo Hernandez, A. E.; Schmidt, Ivan] Univ Tecn Federico Santa Maria, Casilla 110-5, Valparaiso, Chile, Email: carolina.arbelaez@usm.cl; |
| 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:000540500300001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4430 |
| Permanent link to this record |
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| Author |
Arbelaez, C.; Dib, C.; Monsalvez-Pozo, K.; Schmidt, I. |
| Title |
Quasi-Dirac neutrinos in the linear seesaw model |
Type |
Journal Article |
| Year |
2021 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
07 |
Issue |
7 |
Pages |
154 - 22pp |
| Keywords |
Beyond Standard Model; Neutrino Physics |
| Abstract |
We implement a minimal linear seesaw model (LSM) for addressing the Quasi-Dirac (QD) behaviour of heavy neutrinos, focusing on the mass regime of M-N less than or similar to M-W. Here we show that for relatively low neutrino masses, covering the few GeV range, the same-sign to opposite-sign dilepton ratio, R-ll, can be anywhere between 0 and 1, thus signaling a Quasi-Dirac regime. Particular values of R-ll are controlled by the width of the QD neutrino and its mass splitting, the latter being equal to the light-neutrino mass m(nu) in the LSM scenario. The current upper bound on m(nu 1) together with the projected sensitivities of current and future |U-N l|(2) experimental measurements, set stringent constraints on our low-scale QD mass regime. Some experimental prospects of testing the model by LHC displaced vertex searches are also discussed. |
| Address |
[Arbelaez, Carolina; Dib, Claudio; Schmidt, Ivan] Univ Tecn Federico Santa Maria, Ave Espana 1680, Valparaiso, Chile, Email: carolina.arbelaez@usm.cl; |
| 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:000677622200005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4930 |
| Permanent link to this record |
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| Author |
Archidiacono, M.; Gariazzo, S.; Giunti, C.; Hannestad, S.; Tram, T. |
| Title |
Sterile neutrino self-interactions: H-0 tension and short-baseline anomalies |
Type |
Journal Article |
| Year |
2020 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
| Volume |
12 |
Issue |
12 |
Pages |
029 - 20pp |
| Keywords |
cosmological neutrinos; cosmological parameters from CMBR; particle physics – cosmology connection; physics of the early universe |
| Abstract |
Sterile neutrinos with a mass in the eV range have been invoked as a possible explanation of a variety of short baseline (SBL) neutrino oscillation anomalies. However, if one considers neutrino oscillations between active and sterile neutrinos, such neutrinos would have been fully thermalised in the early universe, and would be therefore in strong conflict with cosmological bounds. In this study we first update cosmological bounds on the mass and energy density of eV-scale sterile neutrinos. We then perform an updated study of a previously proposed model in which the sterile neutrino couples to a new light pseudoscalar degree of freedom. Consistently with previous analyses, we find that the model provides a good fit to all cosmological data and allows the high value of H-0 measured in the local universe to be consistent with measurements of the cosmic microwave background. However, new high l polarisation data constrain the sterile neutrino mass to be less than approximately 1 eV in this scenario. Finally, we combine the cosmological bounds on the pseudoscalar model with a Bayesian inference analysis of SBL data and conclude that only a sterile mass in narrow ranges around 1 eV remains consistent with both cosmology and SBL data. |
| Address |
[Archidiacono, Maria] Univ Milan, Via G Celoria 16, I-20133 Milan, Italy, Email: maria.archidiacono@unimi.it; |
| 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 |
1475-7516 |
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:000609105900015 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4688 |
| Permanent link to this record |
