A5018382115- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Black Holes and Theoretical Physics
- Particle Detector Development and Performance
- Noncommutative and Quantum Gravity Theories
- Quantum Mechanics and Applications
- Biofield Effects and Biophysics
- Computational Physics and Python Applications
- Quantum Chromodynamics and Particle Interactions
- Earth Systems and Cosmic Evolution
- Particle Accelerators and Free-Electron Lasers
- Relativity and Gravitational Theory
- Particle accelerators and beam dynamics
- International Science and Diplomacy
- Physics and Engineering Research Articles
- Advanced Thermodynamics and Statistical Mechanics
- Quantum, superfluid, helium dynamics
- Space Science and Extraterrestrial Life
- Quantum Information and Cryptography
- Statistical Mechanics and Entropy
- Paranormal Experiences and Beliefs
- Atomic and Subatomic Physics Research
TU Dortmund University
2015-2024
Indian Institute of Technology Bombay
2021
Federico Santa María Technical University
2010-2013
Centro Científico Tecnológico de Valparaíso
2013
Vanderbilt University
2001-2010
University of Alabama
2007
University of Würzburg
2002-2006
University of Hawaiʻi at Mānoa
2005-2006
Saha Institute of Nuclear Physics
2003
Max Planck Institute for Nuclear Physics
1997-2001
The Heidelberg-Moscow experiment gives the most stringent limit on Majorana neutrino mass. After 24 kg yr of data with pulse shape measurements, we set a lower half-life $0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ decay in ${}^{76}\mathrm{Ge}$ ${T}_{1/2}^{0\ensuremath{\nu}}\ensuremath{\ge}5.7\ifmmode\times\else\texttimes\fi{}{10}^{25}\mathrm{yr}$ at $90%$ C.L. (after PDG98 [C. Caso et al., Eur. Phys. J. C3, 1 (1998]), sensitivity being...
Neutrinoless double beta decay is the most powerful tool to probe not only for Majorana neutrino masses but lepton number violating physics in general. We discuss relations between violation, and mass, review a general Lorentz invariant parametrization of rate, highlight different new models showing how mechanisms can trigger decay, finally possibilities discriminate test these complementary experiments.
We review the potential to probe new physics with neutrinoless double beta decay $(A,Z) \to (A,Z+2) + 2 e^-$. Both standard long-range light neutrino mechanism as well short-range mechanisms mediated by heavy particles are discussed. also stress aspects of connection lepton number violation at colliders and implications for baryogenesis.
The full setup of the Heidelberg-Moscow double \ensuremath{\beta} decay experiment is presented. This gives at present most stringent upper bound, improving neutrino mass limit into sub-eV range. Out 19.2 kg 86% ${\mathrm{enriched}}^{76}$Ge five crystals were grown with a total 11.51 kg. Since February 1995 all detectors, corresponding to 10.96 active mass, are in regular operation Gran Sasso underground laboratory, four them common shield. No signal observed for neutrinoless...
We propose a renormalizable multi-Higgs model with $A_{4}\otimes Z_{2}\otimes Z^{\prime}_{2}$ symmetry, accounting for the experimental deviation from tribimaximal mixing pattern of neutrino matrix. In this framework we study charged lepton and masses mixings. The light are generated via radiative seesaw mechanism, which involves single heavy Majorana neutral scalars running in loops. obtained mixings mass squared splittings good agreement oscillation data both normal inverted hierarchy....
Lepton flavor violating Higgs decays can arise in symmetry models where the sector is responsible for both electroweak and breaking. Here we advocate an ${S}_{4}$ three-Higgs-doublet model tightly constrained changing neutral currents are suppressed by a remnant ${Z}_{3}$ symmetry. A small breaking of this explain $2.4\ensuremath{\sigma}$ excess decay final states with $\ensuremath{\mu}\ensuremath{\tau}$ topology reported recently CMS if new scalars light. The also predicts sizable rates...
We revisit a singlet Majoron model in which neutrino masses arise from the spontaneous violation of lepton number. If obtains mass order MeV, it can play role dark matter. discuss constraints on couplings massive with MeV to neutrinos supernova data. In dense core, Majoron-emitting annihilations are allowed and change signal supernova. Based observation SN1987A, we exclude large range luminosity deleptonization arguments, taking effect background medium into account. does not exceed Q-value...
The relations between the effective Majorana mass of electron neutrino, $m_{ee}$, responsible for neutrinoless double beta decay, and neutrino oscillation parameters are considered. We show that any specific pattern $m_{ee}$ can take value (from zero to existing upper bound) normal hierarchy it have a minimum inverse hierarchy. This means experiments cannot fix in general $m_{ee}$. Mass ranges be predicted terms with additional assumptions about level degeneracy type spectrum. These...
We discuss a possible new resonance in active-sterile neutrino oscillations arising theories with large extra dimensions. Fluctuations the brane effectively increase path-length of active neutrinos relative to sterile through extra-dimensional bulk. Well below resonance, standard oscillation formulas apply. above are suppressed. show that energy range 30--400 MeV allows an explanation all data, including LSND consistent four-neutrino model. A high implies enhanced signal MiniBooNE. low...
Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any preexisting baryon asymmetry of the Universe. In this article, we discuss constraints obtained from an observation neutrinoless double beta decay context. If a new physics mechanism other than standard light neutrino exchange is observed, typical scenarios high-scale baryogenesis will be excluded unless stabilized via some mechanism. We also...
The same leptoquarks that explain the recently observed anomaly in $R_K$ can generate naturally small Majorana neutrino masses at one-loop level through mixing with standard model Higgs boson. This is particularly relevant models least two contributing to $b \rightarrow s ll$ transitions.
Vector leptoquarks provide an elegant solution to a series of anomalies and at the same time generate naturally light neutrino masses through their mixing with standard model Higgs boson. We present simple Froggatt-Nielsen accommodate $B$ physics ${R}_{K}$ ${R}_{D}$, masses, 750 GeV diphoton excess in one cohesive framework adding only two vector singlet scalar fields field content.
A measurement of neutrinoless double beta decay in one isotope does not allow us to determine the underlying physics mechanism. We discuss discrimination mechanisms for by comparing ratios half-life measurements different isotopes. Six prominent examples specific new contributions are analyzed. find that change corresponding half lives varies from 60% supersymmetric models up a factor 5-20 extra-dimensional and left-right-symmetric mechanisms.
Discrete symmetries employed to explain flavor mixing and mass hierarchies can be associated with an enlarged scalar sector which might lead exotic Higgs decay modes. In this paper, we explore such a possibility in scenario $S_3$ symmetry requires three SU(2) doublets. The spectrum is fixed by minimizing the potential, observe that of model leads tantalizing modes potentially observable at CERN Large Hadron Collider (LHC).
Lepton number violation (LNV) mediated by short-range operators can manifest itself in both neutrinoless double beta decay ($0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$) and processes with same-sign dilepton final states at the LHC. We derive limits from existing LHC data $\sqrt{s}=8\text{ }\text{ }\mathrm{TeV}$ compare discovery potential of forthcoming $\sqrt{s}=14\text{ phase sensitivity current future $0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ experiments,...
Abstract We assess the potential of neutrino telescopes to discover quantum-gravity-induced decoherence effects modeled in open-quantum system framework and with arbitrary numbers active dark fermion generations, such as particle matter or sterile neutrinos. The expected damping flavor oscillation probabilities a function energy propagation length thus encodes information about quantum gravity generation multiplicity sector. employ public Monte-Carlo dataset provided by IceCube Collaboration...
New results after 0.69 kg yr of measurement with an enriched 76Ge detector the Heidelberg--Moscow experiment active mass 2.758 are presented. An energy threshold 9 keV and a background level 0.042 counts/(kg d keV) in region between 15 40 was reached.The derived limits on WIMP--nucleon cross section most stringent spin--independent interactions obtained to date by using essentially raw data without subtraction.
In the minimal supersymmetric extension to Standard Model, a non-zero lepton number violating coupling lambda'_111 predicts both neutrinoless double beta decay and resonant single slepton production at LHC. We show that, in this case, if is discovered next generation of experiments, there exist good prospects observe Neutrinoless could otherwise result from different source (such as Majorana neutrino mass). Resonant LHC can therefore discriminate between mechanism others.
We compare the discovery potential of LHC for lepton number violating (LNV) signals with sensitivity current and future double beta decay experiments, assuming $0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ is dominated by heavy particle exchange. consider charged scalar, leptoquark diquark mechanisms decay, covering operators both, smallest largest, possible rates. demonstrate, if were found a half-life below ${10}^{26}--{10}^{27}\text{ }\mathrm{\text{years}}$ positive signal...