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Mario Kadastik

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DOI: 10.1088/1475-7516/2011/03/051
2011
Cited 672 times
PPPC 4 DM ID: a poor particle physicist cookbook for dark matter indirect detection
We provide ingredients and recipes for computing signals of TeV-scale Dark Matter annihilations and decays in the Galaxy and beyond. For each DM channel, we present the energy spectra of at production, computed by high-statistics simulations. We estimate the Monte Carlo uncertainty by comparing the results yielded by the Pythia and Herwig event generators. We then provide the propagation functions for charged particles in the Galaxy, for several DM distribution profiles and sets of propagation parameters. Propagation of e ± is performed with an improved semi-analytic method that takes into account position-dependent energy losses in the Milky Way. Using such propagation functions, we compute the energy spectra of e ± ,p̄ and d̄ at the location of the Earth. We then present the gamma ray fluxes, both from prompt emission and from Inverse Compton scattering in the galactic halo. Finally, we provide the spectra of extragalactic gamma rays. All results are available in numerical form and ready to be consumed.
DOI: 10.1016/j.nuclphysb.2008.11.031
2009
Cited 476 times
Model-independent implications of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:msup><mml:mi>e</mml:mi><mml:mo>±</mml:mo></mml:msup></mml:math>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"><mml:mover accent="true"><mml:mi>p</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:math> cosmic ray spectra on properties of Dark Matter
Taking into account spins, we classify all two-body non-relativistic Dark Matter annihilation channels to the allowed polarization states of Standard Model particles, computing the energy spectra of the stable final-state particles relevant for indirect DM detection. We study the DM masses, annihilation channels and cross sections that can reproduce the PAMELA indications of an e+ excess consistently with the PAMELA p¯ data and the ATIC/PPB-BETS e++e− data. From the PAMELA data alone, two solutions emerge: (i) either the DM particles that annihilate into W,Z,h must be heavier than about 10 TeV or (ii) the DM must annihilate only into leptons. Thus in both cases a DM particle compatible with the PAMELA excess seems to have quite unexpected properties. The solution (ii) implies a peak in the e++e− energy spectrum, which, indeed, seems to appear in the ATIC/PPB-BETS data around 700 GeV. If upcoming data from ATIC-4 and GLAST confirm this feature, this would point to a O(1)TeV DM annihilating only into leptons. Otherwise the solution (i) would be favored. We comment on the implications of these results for DM models, direct DM detection and colliders as well as on the possibility of an astrophysical origin of the excess.
DOI: 10.1140/epjc/s10052-008-0715-2
2008
Cited 315 times
Flavor physics of leptons and dipole moments
This chapter of the report of the “Flavor in the era of the LHC” Workshop discusses the theoretical, phenomenological and experimental issues related to flavor phenomena in the charged lepton sector and in flavor conserving CP-violating processes. We review the current experimental limits and the main theoretical models for the flavor structure of fundamental particles. We analyze the phenomenological consequences of the available data, setting constraints on explicit models beyond the standard model, presenting benchmarks for the discovery potential of forthcoming measurements both at the LHC and at low energy, and exploring options for possible future experiments.
DOI: 10.1088/1475-7516/2012/10/e01
2012
Cited 178 times
Erratum: PPPC 4 DM ID: a poor particle physicist cookbook for dark matter indirect detection
We provide ingredients and recipes for computing signals of TeVscale Dark Matter annihilations and decays in the Galaxy and beyond.For each DM channel, we present the energy spectra of e ± , p, d, γ, (-) ν e,µ,τ at production, computed by high-statistics simulations.We estimate the Monte Carlo uncertainty by comparing the results yielded by the Pythia and Herwig event generators.We then provide the propagation functions for charged particles in the Galaxy, for several DM distribution profiles and sets of propagation parameters.Propagation of e ± is performed with an improved semi-analytic method that takes into account position-dependent energy losses in the Milky Way.Using such propagation functions, we compute the energy spectra of e ± , p and d at the location of the Earth.We then present the gamma ray fluxes, both from prompt emission and from Inverse Compton scattering in the galactic halo.Finally, we provide the spectra of extragalactic gamma rays.All results are available in numerical form and ready to be consumed.
DOI: 10.48550/arxiv.1307.1347
2013
Cited 160 times
Handbook of LHC Higgs Cross Sections: 3. Higgs Properties
This Report summarizes the results of the activities in 2012 and the first half of 2013 of the LHC Higgs Cross Section Working Group. The main goal of the working group was to present the state of the art of Higgs Physics at the LHC, integrating all new results that have appeared in the last few years. This report follows the first working group report Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables (CERN-2011-002) and the second working group report Handbook of LHC Higgs Cross Sections: 2. Differential Distributions (CERN-2012-002). After the discovery of a Higgs boson at the LHC in mid-2012 this report focuses on refined prediction of Standard Model (SM) Higgs phenomenology around the experimentally observed value of 125-126 GeV, refined predictions for heavy SM-like Higgs bosons as well as predictions in the Minimal Supersymmetric Standard Model and first steps to go beyond these models. The other main focus is on the extraction of the characteristics and properties of the newly discovered particle such as couplings to SM particles, spin and CP-quantum numbers etc.
DOI: 10.1007/jhep05(2012)061
2012
Cited 159 times
Implications of the 125 GeV Higgs boson for scalar dark matter and for the CMSSM phenomenology
We study phenomenological implications of the ATLAS and CMS hint of a 125 ± 1 GeV Higgs boson for the singlet, and singlet plus doublet non-supersymmetric dark matter models, and for the phenomenology of the CMSSM. We show that in scalar dark matter models the vacuum stability bound on Higgs boson mass is lower than in the standard model and the 125 GeV Higgs boson is consistent with the models being valid up the GUT or Planck scale. We perform a detailed study of the full CMSSM parameter space keeping the Higgs boson mass fixed to 125 ± 1 GeV, and study in detail the freeze-out processes that imply the observed amount of dark matter. After imposing all phenomenological constraints except for the muon (g − 2) μ , we show that the CMSSM parameter space is divided into well separated regions with distinctive but in general heavy sparticle mass spectra. Imposing the (g − 2) μ constraint introduces severe tension between the high SUSY scale and the experimental measurements — only the slepton co-annihilation region survives with potentially testable sparticle masses at the LHC. In the latter case the spin-independent DM-nucleon scattering cross section is predicted to be below detectable limit at the XENON100, but might be of measurable magnitude in the general case of light dark matter with large bino-higgsino mixing and unobservably large scalar masses.
DOI: 10.1140/epjc/s10052-017-4829-2
2017
Cited 89 times
Prospects for charged Higgs searches at the LHC
The goal of this report is to summarize the current situation and discuss possible search strategies for charged scalars, in non-supersymmetric extensions of the Standard Model at the LHC. Such scalars appear in Multi-Higgs-Doublet models, in particular in the popular Two-Higgs-Doublet model, allowing for charged and additional neutral Higgs bosons. These models have the attractive property that electroweak precision observables are automatically in agreement with the Standard Model at the tree level. For the most popular version of this framework, Model II, a discovery of a charged Higgs boson remains challenging, since the parameter space is becoming very constrained, and the QCD background is very high. We also briefly comment on models with dark matter which constrain the corresponding charged scalars that occur in these models. The stakes of a possible discovery of an extended scalar sector are very high, and these searches should be pursued in all conceivable channels, at the LHC and at future colliders.
DOI: 10.1103/physrevd.80.085020
2009
Cited 98 times
Dark matter as the signal of grand unification
We argue that the existence of dark matter (DM) is a possible consequence of grand unification (GUT) symmetry breaking. In GUTs like $SO(10)$, discrete ${Z}_{2}$ matter parity $(\ensuremath{-}1{)}^{3(B\ensuremath{-}L)}$ survives despite broken $B\ensuremath{-}L$, and group theory uniquely determines that the only possible ${Z}_{2}$-odd matter multiplets belong to representation $\mathbf{16}$. We construct the minimal nonsupersymmetric $SO(10)$ model containing one scalar $\mathbf{16}$ for DM and study its predictions below ${M}_{G}$. We find that electroweak symmetry breaking occurs radiatively due to DM couplings to the standard model Higgs boson. For thermal relic DM the mass range ${M}_{\mathrm{DM}}\ensuremath{\sim}\mathcal{O}(0.1--1)\text{ }\text{ }\mathrm{TeV}$ is predicted by model perturbativity up to ${M}_{G}$. For ${M}_{\mathrm{DM}}\ensuremath{\sim}\mathcal{O}(1)\text{ }\text{ }\mathrm{TeV}$ to explain the observed cosmic ray anomalies with DM decays, there exists a lower bound on the spin-independent direct detection cross section within the reach of planned experiments.
DOI: 10.1103/physrevd.77.115023
2008
Cited 88 times
Direct determination of neutrino mass parameters at future colliders
If the observed light neutrino masses are induced by their Yukawa couplings to singlet right-handed neutrinos, the natural smallness of those makes direct collider tests of the electroweak scale neutrino mass mechanisms difficult in the simplest models. In the triplet Higgs seesaw scenario the smallness of light neutrino masses may come from the smallness of $B\ensuremath{-}L$ breaking parameters, allowing sizable Yukawa couplings even for a TeV scale triplet. We show that, in this scenario, measuring the branching fractions of doubly charged Higgs to different same-charged lepton flavors at CERN LHC and/or ILC experiments will allow one to measure the neutrino mass parameters that neutrino oscillation experiments are insensitive to, including the neutrino mass hierarchy, lightest neutrino mass, and Majorana phases.
DOI: 10.1103/physrevd.81.015002
2010
Cited 74 times
Matter parity as the origin of scalar dark matter
We extend the concept of matter parity ${P}_{M}=(\ensuremath{-}1{)}^{3(B\ensuremath{-}L)}$ to nonsupersymmetric theories and argue that ${P}_{M}$ is the natural explanation to the existence of dark matter of the Universe. We show that the nonsupersymmetric dark matter must be contained in a scalar $\mathbf{16}$ representation(s) of $SO(10)$, thus the unique low-energy dark matter candidates are ${P}_{M}$-odd complex scalar singlet(s) $S$ and an inert scalar doublet(s) ${H}_{2}$. We have calculated the thermal relic dark matter (DM) abundance of the model and shown that its minimal form may be testable at LHC via the standard model (SM) Higgs boson decays ${H}_{1}\ensuremath{\rightarrow}\mathrm{DM}\text{ }\mathrm{DM}$. The PAMELA anomaly can be explained with the decays $\mathrm{DM}\ensuremath{\rightarrow}\ensuremath{\nu}lW$ induced via seesawlike operator which is additionally suppressed by the Planck scale. Because the SM fermions are odd under matter parity too, the DM sector is just our scalar relative.
DOI: 10.1016/j.nuclphysb.2007.07.014
2007
Cited 70 times
Testing neutrino masses in little Higgs models via discovery of doubly charged Higgs at LHC
We have investigated the possibility of direct tests of little Higgs models incorporating triplet Higgs neutrino mass mechanism at LHC experiments. We have performed Monte Carlo studies of Drell–Yan pair production of doubly charged Higgs boson Φ++ followed by its leptonic decays whose branching ratios are fixed from the neutrino oscillation data. We propose appropriate selection rules for the four-lepton signal, including reconstructed taus, which are optimized for the discovery of Φ++ with the lowest LHC luminosity. As the Standard Model background can be effectively eliminated, an important aspect of our study is the correct statistical treatment of the LHC discovery potential. Adding detection efficiencies and measurement errors to the Monte Carlo analyses, Φ++ can be discovered up to the mass 250 GeV in the first year of LHC, and 700 GeV mass is reachable for the integrated luminosity L=30fb−1.
DOI: 10.1016/j.nuclphysb.2011.08.003
2011
Cited 67 times
Implications of Xenon100 and LHC results for Dark Matter models
We perform a fit to the recent Xenon100 data and study its implications for Dark Matter scenarios. We find that Inelastic Dark Matter is disfavored as an explanation to the DAMA/LIBRA annual modulation signal. Concerning the scalar singlet DM model, we find that the Xenon100 data disfavors its constrained limit. We study the CMSSM as well as the low scale phenomenological MSSM taking into account latest Tevatron and LHC data (1.1/fb) about sparticles and Bs→μμ. After the EPS 2011 conference, LHC excludes the “Higgs-resonance” region of DM freeze-out and Xenon100 disfavors the “well-tempered” bino/higgsino, realized in the “focus-point” region of the CMSSM parameter space. The preferred region shifts to heavier sparticles, higher fine-tuning, higher tanβ and the quality of the fit deteriorates.
DOI: 10.1016/j.nuclphysb.2013.05.002
2013
Cited 60 times
Addendum including AMS 2013 data to “Model-independent implications of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>±</mml:mo></mml:mrow></mml:msup></mml:math>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"><mml:mover accent="true"><mml:mi>p</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:math> cosmic ray spectra on properties of Dark …
We update the paper including the 2013 AMS positron data.
DOI: 10.1140/epjc/s10052-008-0713-4
2008
Cited 55 times
Collider aspects of flavor physics at high Q
This chapter of the "Flavor in the era of LHC" workshop report discusses flavor-related issues in the production and decays of heavy states at the LHC at high momentum transfer Q, both from the experimental and the theoretical perspective. We review top quark physics, and discuss the flavor aspects of several extensions of the standard model, such as supersymmetry, little Higgs models or models with extra dimensions. This includes discovery aspects, as well as the measurement of several properties of these heavy states. We also present publicly available computational tools related to this topic.
DOI: 10.1016/j.physletb.2009.12.005
2010
Cited 54 times
Enhanced anti-deuteron Dark Matter signal and the implications of PAMELA
We show that the jet structure of DM annihilation or decay products enhances the anti-deuterium production rate by orders of magnitude compared to the previous computations done assuming a spherically symmetric coalescence model. In particular, in the limit of heavy DM, M >> m_p, we get a constant rather than 1/M^2 suppressed anti-deuterium production rate. Therefore, a detectable anti-deuterium signal is compatible with the lack of an excess in the anti-proton PAMELA flux. Most importantly, cosmic anti-deuterium searches become sensitive to the annihilations or decays of heavy DM, suggesting to extend the experimental anti-deuterium searches above the O(1) GeV scale.
DOI: 10.1140/epjc/s10052-021-08950-y
2021
Cited 20 times
Evolutionary algorithms for hyperparameter optimization in machine learning for application in high energy physics
Abstract The analysis of vast amounts of data constitutes a major challenge in modern high energy physics experiments. Machine learning (ML) methods, typically trained on simulated data, are often employed to facilitate this task. Several choices need to be made by the user when training the ML algorithm. In addition to deciding which ML algorithm to use and choosing suitable observables as inputs, users typically need to choose among a plethora of algorithm-specific parameters. We refer to parameters that need to be chosen by the user as hyperparameters. These are to be distinguished from parameters that the ML algorithm learns autonomously during the training, without intervention by the user. The choice of hyperparameters is conventionally done manually by the user and often has a significant impact on the performance of the ML algorithm. In this paper, we explore two evolutionary algorithms: particle swarm optimization and genetic algorithm, for the purposes of performing the choice of optimal hyperparameter values in an autonomous manner. Both of these algorithms will be tested on different datasets and compared to alternative methods.
DOI: 10.1140/epjc/s10052-012-1976-3
2012
Cited 39 times
Searches for new physics: Les Houches recommendations for the presentation of LHC results
We present a set of recommendations for the presentation of LHC results on searches for new physics, which are aimed at providing a more efficient flow of scientific information between the experimental collaborations and the rest of the high energy physics community, and at facilitating the interpretation of the results in a wide class of models. Implementing these recommendations would aid the full exploitation of the physics potential of the LHC.
DOI: 10.1103/physrevlett.104.201301
2010
Cited 24 times
Electroweak Symmetry Breaking from the Soft Portal into Dark Matter and Prediction for Direct Detection
Scalar dark matter (DM) can have dimensionful coupling to the Higgs boson-the soft portal into DM-which is predicted to be unsuppressed by the underlying SO(10) grand unified theory (GUT). The dimensionful coupling can be large, μ/v>>1, without spoiling the perturbativity of low energy theory up to the GUT scale. We show that the soft portal into DM naturally triggers radiative electroweak symmetry breaking (EWSB) via large 1-loop DM corrections to the effective potential. In this scenario, EWSB, the DM thermal freeze-out cross section, and DM scattering on nuclei are all dominated by the same coupling, predicting the DM mass range to be 700 GeV<M(DM)<2 TeV. The spin-independent direct detection cross section is predicted to be just below the present experimental bounds.
DOI: 10.1103/physrevd.81.029903
2010
Cited 24 times
Erratum: Dark matter as the signal of grand unification [Phys. Rev. D<b>80</b>, 085020 (2009)]
We argue that the existence of Dark Matter (DM) is a possible consequence of GUT symmetry breaking. In GUTs like SO(10), discrete Z_2 matter parity (-1)^{3(B-L)} survives despite of broken B-L, and group theory uniquely determines that the only possible Z_2-odd matter multiplets belong to representation 16. We construct the minimal non-SUSY SO(10) model containing one scalar 16 for DM and study its predictions below M_{G}. We find that EWSB occurs radiatively due to DM couplings to the SM Higgs boson. For thermal relic DM the mass range M_{DM}\sim (0.1-1) TeV is predicted by model perturbativity up to M_{G}. For M_{DM}\sim (1) TeV to explain the observed cosmic ray anomalies with DM decays, there exists a lower bound on the spin-independent direct detection cross section within the reach of planned experiments.
DOI: 10.1016/j.physletb.2005.09.056
2005
Cited 24 times
Running of low-energy neutrino masses, mixing angles and CP violation
We calculate the running of low-energy neutrino parameters from the bottom up, parameterizing the unknown seesaw parameters in terms of the dominance matrix $R$. We find significant running only if the $R$ matrix is non-trivial and the light-neutrino masses are moderately degenerate. If the light-neutrino masses are very hierarchical, the quark-lepton complementarity relation $\theta_c + \theta_{12} = \pi/4$ is quite stable, but $\theta_{13,23}$ may run beyond their likely future experimental errors. The running of the oscillation phase $\delta$ is enhanced by the smallness of $\theta_{13}$, and jumps in the mixing angles occur in cases where the light-neutrino mass eigenstates cross.
DOI: 10.1016/j.physletb.2010.09.068
2010
Cited 14 times
Implications of Dark Matter direct detection results on LHC physics
The requirements of electroweak symmetry breaking (EWSB) and correct thermal relic density of Dark Matter (DM) predict large DM spin-independent direct detection cross section in scalar DM models based on SO(10) non-supersymmetric GUTs. Assuming that the two signal-like events recently observed by CDMS II experiment actually are DM particle recoils on nuclei, we study implications of this assumption on EWSB, on the Higgs boson mass and on direct production of scalar DM at LHC experiments. In our scenario this assumption indicates relatively light DM, MDM∼O(80) GeV, implying large DM pair production cross section at LHC in correlation with the spin-independent direct DM detection cross section. Most importantly, the next-to-lightest dark scalar SNL is predicted to be long-lived, providing distinctive experimental signatures of displaced vertex of two leptons or jets plus missing transverse energy.
DOI: 10.1103/physrevd.84.031701
2011
Cited 9 times
Direct detection and CMB constraints on the light dark matter scenario of top quark asymmetry and dijet excess at the Tevatron
We study in detail the model by Isidori and Kamenik that is claimed to explain the top quark forward-backward asymmetry at Tevatron, provide GeV-scale dark matter (DM), and possibly improve the agreement between data and theory in Tevatron W+jj events. We compute the DM thermal relic density, the spin-independent DM-nucleon scattering cross section, and the cosmic microwave background constraints on both Dirac and Majorana neutralino DM in the parameter space that explains the top asymmetry. A stable light neutralino is not allowed unless the local DM density is 3-4 times smaller than expected, in which case Dirac DM with mass around 3 GeV may be possible, to be tested by the Planck mission. The model predicts a too broad excess in the dijet distribution and a strong modification of the missing E_T distribution in W+jj events.
DOI: 10.1088/1742-6596/219/6/062055
2010
Cited 6 times
Debugging data transfers in CMS
The CMS experiment at CERN is preparing for LHC data taking in several computing preparation activities. In early 2007 a traffic load generator infrastructure for distributed data transfer tests was designed and deployed to equip the WLCG tiers which support the CMS virtual organization with a means for debugging, load-testing and commissioning data transfer routes among CMS computing centres. The LoadTest is based upon PhEDEx as a reliable, scalable data set replication system. The Debugging Data Transfers (DDT) task force was created to coordinate the debugging of the data transfer links. The task force aimed to commission most crucial transfer routes among CMS tiers by designing and enforcing a clear procedure to debug problematic links. Such procedure aimed to move a link from a debugging phase in a separate and independent environment to a production environment when a set of agreed conditions are achieved for that link. The goal was to deliver one by one working transfer routes to the CMS data operations team. The preparation, activities and experience of the DDT task force within the CMS experiment are discussed. Common technical problems and challenges encountered during the lifetime of the taskforce in debugging data transfer links in CMS are explained and summarized.
DOI: 10.1109/nssmic.2008.4775085
2008
Cited 4 times
The CMS data transfer test environment in preparation for LHC data taking
The CMS experiment is preparing for LHC data taking in several computing preparation activities. In distributed data transfer tests, in early 2007 a traffic load generator infrastructure was designed and deployed, to equip the WLCG Tiers which support the CMS Virtual Organization with a means for debugging, load-testing and commissioning data transfer routes among CMS Computing Centres. The LoadTest is based upon PhEDEx as a reliable, scalable dataset replication system. In addition, a Debugging Data Transfers (DDT) Task Force was created to coordinate the debugging of data transfer links in the preparation period and during the Computing Software and Analysis challenge in 2007 (CSA07). The task force aimed to commission most crucial transfer routes among CMS tiers by designing and enforcing a clear procedure to debug problematic links. Such procedure aimed to move a link from a debugging phase in a separate and independent environment to a production environment when a set of agreed conditions are achieved for that link. The goal was to deliver one by one working transfer routes to Data Operations. The experiences with the overall test transfers infrastructure within computing challenges - as in the WLCG Common-VO Computing Readiness Challenge (CCRC’08) - as well as in daily testing and debugging activities are reviewed and discussed, and plans for the future are presented.
DOI: 10.48550/arxiv.0912.3797
2009
Cited 3 times
Implications of the CDMS result on Dark Matter and LHC physics
The requirements of electroweak symmetry breaking (EWSB) and correct thermal relic density of Dark Matter (DM) predict large spin-independent direct detection cross section in scalar DM models based on underlying SO(10) non-supersymmetric GUT. Interpreting the CDMS signal events as DM recoil on nuclei, we study implications of this assumption on EWSB, Higgs boson mass and direct production of scalar DM at LHC experiments. We show that this interpretation indicates relatively light DM, M_DM ~ O(100) GeV, with large pair production cross section at LHC in correlation with the spin-independent direct DM detection cross section. The next-to-lightest dark scalar S_NL is predicted to be long-lived, providing distinctive experimental signatures of displaced vertex of two leptons or jets plus missing transverse energy.
2008
Doubly charged Higgs boson decays and implications on neutrino physics
2011
Implications of 125 GeV Higgs boson on scalar dark matter and on the CMSSM phenomenology
DOI: 10.3176/phys.math.2006.2.04
2006
Studying doubly charged Higgs pair production at the LHC
The little Higgs models predict a rich phenomenology for the future collider experiments. Our attention is focused on the littlest Higgs model. We carry out a Monte Carlo study of the doubly charged Higgs pair production (pp ! ' ++ ' ii ) in a typical LHC experiment. The branching ratios are fixed using an assumption that, in addition, the observed masses of the neutrinos are generated by triplet Higgs: BR(' §§ ! § § ) = BR(' §§ ! § ? § ) = BR(' §§ ! ? § ? § ) = 1=3. We study the invariant mass distribution of same-charged muon pairs (' §§ ! 2 §§ ) together with the background processes from the standard model: b b, t, and ZZ production. To suppress the background, we propose a new type of selection rule, suitable in the case of production of the pairs of equal mass particles (' §§ ). This selection rule ensures high significance of the signal over the background of the standard model and implies very small cut of the signal under study. At the Monte Carlo level the doubly charged Higgs can be visible at the LHC in the mass range up to approximate 1 TeV.
DOI: 10.3176/phys.math.2005.2.05
2005
The first scientific results from the Estonian Grid
We present first scientific results, technical details and recent developments in the Estonian Grid. Ideas and concepts behind Grid technology are described. We mention some most crucial parts of a Grid system, as well as some unique possibilities in the Estonian situation. Scientific applications currently running on Estonian Grid are listed. We discuss the first scientific computations and results the Estonian Grid. The computations show that the middleware is well chosen and the Estonian Grid has remarkable stability and scalability. The authors present the collected results and experiences of the development of the Estonian Grid and add some ideas of the near future of the Estonian Grid.
2016
Revolutsioon transpordis, liikumine elektromobiilsuse poole Tesla näitel. PhD Mario Kadastik
Revolutsioon transpordis, liikumine elektromobiilsuse poole Tesla naitel. PhD Mario Kadastik
2009
Less-dimensions and matter parity as the origin of Dark Matter
We extend the concept of matter parity $P_M=(-1)^{3(B-L)}$ to non-supersymmetric theories and argue that $P_M$ is the natural explanation to the existence of Dark Matter of the Universe. We show that the non-supersymmetric Dark Matter must be contained in scalar 16 representation(s) of $SO(10),$ thus the unique low energy Dark Matter candidates are $P_M$-odd complex scalar singlet(s) $S$ and inert scalar doublet(s) $H_2.$ We have calculated the thermal relic Dark Matter abundance of the model and shown that its minimal form may be testable at LHC via the SM Higgs boson decays $H_1\to DM DM.$ The PAMELA anomaly can be explained with the decays $DM\to \nu l W$ induced via seesaw-like operator which is additionally suppressed by Planck scale. Because the SM fermions are odd under matter parity too, the DM sector is just our scalar relative.
2008
Doubly charged Higgs boson decays and implications on neutrino physics.Kahekordse laenguga Higgsi bosoni lagunemiste analüüs ja selle mõju neutriinofüüsikale
DOI: 10.1007/978-3-540-95942-7_2
2009
Collider aspects of flavor physics at high Q
DOI: 10.1007/978-3-540-95942-7_1
2009
Flavor physics of leptons and dipole moments
DOI: 10.48550/arxiv.physics/0411024
2004
First scientific results from the Estonian Grid
We present first scientific results, technical details and recent developments in the Estonian Grid. Ideas and concepts behind Grid technology are described. We mention some most crucial parts of a Grid system, as well as some unique possibilities in the Estonian situation. Scientific applications currently running on Estonian Grid are listed. We discuss the first scientific computations and results the Estonian Grid. The computations show that the middleware is well chosen and the Estonian Grid has remarkable stability and scalability. The authors present the collected results and experiences of the development of the Estonian Grid and add some ideas of the near future of the Estonian Grid.