Results for "S. M. Shaaban"

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Examining the cancellation mechanism of neutron EDM in a model with dilaton-dominated susy breakingMar 21 1999Oct 12 1999We examine the cancellation mechanism between the different contributions to the electric dipole moment of the neutron in a model with dilaton-dominated SUSY breaking. We find these accidental cancellations occur at few points in parameter space. For ... More
Cumulative whistler instability in fast solar winds: Constraints of electron temperature anisotropyApr 12 2019Context. Solar outflows are a considerable source of free energy which accumulates in multiple forms like beaming (or drifting) components and/or temperature anisotropies. However, kinetic anisotropies of plasma particles do not grow indefinitely and ... More
Effects of suprathermal electrons on the proton temperature anisotropy in space plasmas: Electromagnetic ion-cyclotron instabilityFeb 12 2016May 11 2016In collision-poor plasmas from space, e.g., the solar wind and planetary magnetospheres, the kinetic anisotropy of the plasma particles is expected to be regulated by the kinetic instabilities. Driven by an excess of ion (proton) temperature perpendicular ... More
The Interplay of the Solar Wind Core and Suprathermal Electrons: A Quasilinear Approach for Firehose InstabilityJan 31 2019In the solar wind an equipartition of kinetic energy densities can be easily established between thermal and suprathermal electrons and the instability conditions are markedly altered by the interplay of these two populations. The new thresholds derived ... More
Firehose constraints for the solar wind suprathermal electronsApr 19 2016The indefinite increase of temperature predicted by the solar wind expansion in the direction parallel to the interplanetary magnetic field is already notorious for not being confirmed by the observations. In hot and dilute plasmas from space particle-particle ... More
Shaping the solar wind temperature anisotropy by the interplay of electron and proton instabilitiesDec 03 2016A variety of nonthermal characteristics like kinetic, e.g., temperature, anisotropies and suprathermal populations (enhancing the high energy tails of the velocity distributions) are revealed by the in-situ observations in the solar wind indicating quasistationary ... More
Quasilinear Approach of the Whistler Heat-Flux Instability in the Solar WindMar 19 2019The hot beaming (or strahl) electrons responsible for the main electron heat-flux in the solar wind are believed to be self-regulated by the electromagnetic beaming instabilities, also known as the heat-flux instabilities. Here we report the first quasi-linear ... More
On "non-Hermitian Quantum Mechanics"Apr 13 2008A series of recent papers ``Faster than Hermitian Quantum Mechanics'' and related articles made a point of the possibility of a non-Hermitian, but PT-symmetric, operator to play the role of a Hamiltonian. In particular, they show that with an appropriate ... More
Supersymmetric contributions to B --> K pi in the view of recent experimental resultAug 14 2006Supersymmetric contributions to the branching ratios and CP asymmetries of B--> K pi decays are analyzed in the view of recent experimental measurements. We show that supersymmetry can still provide a natural solution to the apparent discrepancy between ... More
CP violation in supersymmetric models with Hermitian Yukawa couplings and A-termsFeb 22 2002Feb 24 2002We analyse the CP violation in supersymmetric models with Hermitian Yukawa and trilinear couplings. We show that Hermitian Yukawa matrices can be implemented in supersymmetric models with SU(3) flavor symmetry. An important feature of this class of models ... More
Low scale B-L extension of the Standard Model at the LHCNov 15 2006May 13 2007The fact that neutrinos are massive indicates that the Standard Model (SM) requires extension. We propose a low energy (<TeV) B-L extension of the SM, which is based on the gauge group SU(3)_C x SU(2)_L x U(1)_Y x U(1)_{B-L}. We show that this model provides ... More
Supersymmetric Sum Rules In Minimal Superstring UnificationNov 08 1996The Minimal superstring unification, assuming orbifold compactification, provides interesting and rather detailed implications on physics at low energy. The interesting feature of this model is that the masses of the spectrum are related since all of ... More
Radiative Symmetry Breaking in Supersymmetric $B-L$ Models with Inverse SeesawJun 29 2016Sep 28 2016We study the radiative symmetry breaking of B-L in supersymmetric models with inverse seesaw mechanism. We show that for a wide region of parameter space the radiative corrections can drive the squared mass of the extra Higgs boson from positive initial ... More
CP violation in supersymmetric theoriesDec 03 2002We review the present status of CP violating problem in supersymmetric extensions of the standard model. We analyze the constraints imposed by the experimental limits of the electron, neutron, and mercury electric dipole moments on the supersymmetric ... More
Cosmological implications of supersymmetric CP violating phasesDec 22 1999We show that large SUSY phases have no significant effect on the relic density of the lightest supersymmetric particle (LSP). However, they are very significant for the detection rates. We emphasise that the phase of the trilinear coupling increase the ... More
Supersymmetric contribution to the CP asymmetry of B-> J/ψφin the light of recent B_s -\bar{B}_s measurementsMay 01 2006Jul 24 2006We derive new model independent constraints on the supersymmetric extensions of the standard model from the new experimental measurements of B_s -\bar{B}_s mass difference. We point out that supersymmetry can still give a significant contribution to the ... More
Supersymmetric contributions to B -> D K and the determination of angle γApr 13 2006May 21 2006We analyze supersymmetric contributions to B^- -> D^0 K^- and B^- ->\bar{D}^0 K^- processes. We investigate the possibility that supersymmetric CP violating phases can affect our determination for the angle \gamma in the unitary triangle of Cabibbo-Kobayashi-Maskaw ... More
Non universal gaugino phases and the LSP relic densityOct 19 1999May 17 2000The cosmological relic density of the lightest supersymmetric particle (LSP) of type I string derived model is calculated. This model can accommodate large values of CP violating phases, and the electron and neutron electric dipole moments satisfy the ... More
Lepton flavor violation in supersymmetric B-L extension of the standard modelJul 09 2009Jan 20 2010Supersymmetric B-L extension of the Standard Model (SM) is one of the best candidate for physics beyond the SM that accounts for TeV scale seesaw mechanism and provides an attractive solution for the Higgs naturalness problem. We analyze the charged lepton ... More
TeV Scale Gauged B-L With Inverse Seesaw MechanismMar 31 2010Dec 20 2011We propose a modified version of the TeV scale B-L extension of the standard model, where neutrino masses are generated through the inverse seesaw mechanism. We show that heavy neutrinos associated with this model can be accessible via clean signals at ... More
Supersymmetric contributions to the CP asymmetry of the B --> phi K and B --> eta' KNov 10 2004Nov 17 2004We analyse the CP asymmetry of the B --> phi K and B --> eta' K processes in general supersymmetric models. We consider both gluino and chargino exchanges in a model independent way by using the mass insertion approximation method. We adopt the QCD factorization ... More
CP asymmetries and branching ratios of B --> K πin supersymmetric modelsMay 17 2005We analyze the supersymmetric contributions to the direct and mixing CP asymmetries and also to the branching ratios of the B --> K \pi decays in a model independent way. We consider both gluino and chargino exchanges and emphasize that a large gluino ... More
Probing Flavor Structure in Supersymmetric TheoriesAug 01 2005We analyze the possibility of probing the supersymmetric flavor structure through the constraints of the K and B meson systems and those of the electric dipole moments. We show that combining these constraints would favor SUSY models with large flavor ... More
Naturalness and Dark Matter Properties of the BLSSMJun 05 2017Jun 07 2017In this report, we compare the naturalness and Dark Matter (DM) properties of the Minimal Supersymmetric Standard Model (MSSM) and the $B-L$ Supersymmetric Standard Model (BLSSM), with universality in both cases. We do this by adopting standard measures ... More
Naturalness and Dark Matter in the BLSSMFeb 06 2017We study the naturalness properties of the $B-L$ Supersymmetric Standard Model (BLSSM) and compare them to those of the Minimal Supersymmetric Standard Model (MSSM) at both low (i.e., Large Hadron Collider) energies and high (i.e., unification) scales. ... More
Supersymmetric Gauged B-L Model of Dark Matter and Fine TuningOct 03 2017We investigate how the Fine-Tuning (FT) in the B-L Supersymmetric Standard Model (BLSSM) compares to the Minimally Supersymmetric Standard Model (MSSM), where both models have universality. This is done for two scales: both low (i.e. collider) and high ... More
Atomki Anomaly in Family-Dependent $U(1)'$ Extension of the Standard ModelNov 19 2018Dec 11 2018In the context of a gauge invariant, non-anomalous and family-dependent (non-universal) $U(1)'$ extension of the Standard Model, wherein a new high scale mechanism generates masses and couplings for the first two fermion generations and the standard Higgs ... More
Yukawa Unification in Moduli-dominant SUSY BreakingJun 24 1997We study Yukawa unification in string models with moduli-dominant SUSY breaking. This type of SUSY breaking in general leads to non-universal soft masses, i.e., soft scalar masses and gaugino masses. Such non-universality is important for phenomenological ... More
Sterile neutrino dark matter in $B-L$ extension of the standard model and galactic 511 keV lineApr 02 2008Dec 22 2008Sterile right-handed neutrinos can be naturally embedded in a low scale gauged $U(1)_{B-L}$ extension of the standard model. We show that, within a low reheating scenario, such a neutrino is an interesting candidate for dark matter. We emphasize that ... More
The Enigma of the Dark MatterOct 09 2001One of the great scientific enigmas still unsolved, the existence of dark matter, is reviewed. Simple gravitational arguments imply that most of the mass in the Universe, at least 90%, is some (unknown) non-luminous matter. Some particle candidates for ... More
Supersymmetric CP violating Phases and the LSP relic density and detection ratesApr 25 1999Sep 24 1999For varying values of $\tan\beta$, we study the effect of CP violating phases from the soft supersymmetry breaking terms in string-inspired models on the relic abundance and detection rates of the lightest neutralino (LSP). We find that the phases have ... More
Supersymmetric CP violation $ε'/ε$ due to asymmetric A-matrixJun 15 1999We study contributions of supersymmetric CP phases to the CP violation $\epsilon'/\epsilon$ in models with asymmetric $A$-matrices. We consider asymmetric $A$-matrices, which are obtained from string-inspired supergravity. We show that a certain type ... More
Fermion masses and mixing in $Δ(27)$ flavour modelJun 25 2014An extension of the Standard Model (SM) based on the non-Abelian discrete group $\Delta(27)$ is considered. The $\Delta(27)$ flavour symmetry is spontaneously broken only by gauge singlet scalar fields, therefore our model is free from any flavour changing ... More
Right-handed Sneutrino Inflation in SUSY B-L with Inverse SeesawAug 09 2011Oct 16 2011We propose a scenario for realizing inflation in the framework of supersymmetric B-L extension of the Standard Model. We find that one of the associated right-handed sneutrinos (the superpartner of the Standard Model singlet fermion) can provide a new ... More
Low energy consequences from supersymmetric models with left-right symmetryJun 16 1999We consider several low energy consequences arising from a class of supersymmetric models based on the gauge groups $SU(2)_L\times SU(2)_R \times U(1)_{B-L}$ and $SU(4)_C\times SU(2)_L \times SU(2)_R$ in which the gauge hierarchy and $\mu$ problems have ... More
Supersymmetry and CP violation in B^0_s - \bar{B}^0_s mixing and B^0_s -> J/ψφdecayMay 13 2009Supersymmetric contributions to time independent asymmetry in $B^0_s \to J/\psi \phi$ process are analyzed in the view of the recent Tevatron experimental measurements. We show that the experimental limits of the mass difference $\Delta M_{B_s}$ and the ... More
Can the CKM phase be the only source of CP violation?Jun 18 2003Nov 14 2003We address the question of whether the CP violating phase in the CKM mixing matrix can be the only source of all CP violation. We show that in supersymmetric models with new flavour structure beyond the Yukawa matrices, the CKM phase can generate the ... More
Sneutrino Dark Matter, Constraints and PerspectivesApr 20 2018The prevalent Dark Matter (DM) candidate of the (B-L) Supersymmetric Standard Model (BLSSM) is the Right Handed (RH) sneutrino. In this work we assess the ability of ground and space based experiments to establish the nature of this particle, through ... More
Prospects for Sneutrino Dark Matter in the BLSSMApr 25 2018The $(B-L)$ Supersymmetric Standard Model (BLSSM) motivates several Dark Matter (DM) candidates beyond the Minimally Supersymmetric Standard Model (MSSM). We assess the comparative naturalness of the two models and discuss the potential detection properties ... More
Sneutrino Dark Matter in the BLSSMDec 14 2017In the framework of the $(B-L)$ Supersymmetric Standard Model (BLSSM), we assess the ability of ground and space based experiments to establish the nature of its prevalent Dark Matter (DM) candidate, the sneutrino, which could either be CP-even or -odd. ... More
Muon Anomalous Magnetic Moment in SUSY B-L Model with Inverse SeesawSep 17 2015Motivated by the tension between the Higgs mass and muon g-2 in minimal supersymmetric standard model (MSSM), we analyze the muon g-2 in supersymmertic B-L extension of the standard model (BLSSM) with inverse seesaw mechanism. In this model, the Higgs ... More
Right-handed Sneutrino Dark Matter in Supersymmetric B-L ModelFeb 21 2011Jun 22 2011We show that the lightest right-handed sneutrino in TeV scale supersymmetric B-L model with inverse seesaw mechanism is a viable candidate for cold dark matter. We find that it accounts for the observed dark matter relic abundance in a wide range of parameter ... More
Lightweight Distance bound Protocol for Low Cost RFID TagsApr 08 2010May 07 2010Almost all existing RFID authentication schemes (tag/reader) are vulnerable to relay attacks, because of their inability to estimate the distance to the tag. These attacks are very serious since it can be mounted without the notice of neither the reader ... More
EDM-free supersymmetric CP violation with non-universal soft termsMar 09 2000Mar 13 2000Non-universality in the soft breaking terms is a common feature in most superstring inspired SUSY models. This property is required to obtain sizeable CP violation effects from SUSY and, on the other hand, can be used to avoid the Electric Dipole Moment ... More
CP violation in supersymmetric model with non-degenerate A-termsMar 31 1999We study the CP phases of the soft supersymmetry breaking terms in string-inspired models with non-universal trilinear couplings. We show that such non-universality plays an important role on all CP violating processes. In particular these new supersymmetric ... More
Low Energy Implications of Minimal Superstring UnificationNov 09 1995We study the phenomenological implications of effective supergravities based on string vacua with spontaneously broken N=1 supersymmetry by dilaton and moduli $F$-terms. We further require Minimal String Unification, namely that large string threshold ... More
CP Phases of Neutrino Mixing in a Supersymmetric B-L Gauge Model with T_7 Lepton Flavor SymmetryApr 12 2012Apr 17 2012In a recently proposed renormalizable model of neutrino mixing using the non-Abelian discrete symmetry T_7 in the context of a supersymmetric extension of the Standard Model with gauged U(1)_{B-L}, a correlation was obtained between \theta_{13} and \theta_{23} ... More
Generalized Lepton Number and Dark Left-Right Gauge ModelJan 08 2009Feb 06 2009In a left-right gauge model of particle interactions, the left-handed fermion doublet (nu,e)_L is connected to its right-handed counterpart (n,e)_R through a scalar bidoublet so that e_L pairs with e_R, and nu_L with n_R to form mass terms. Suppose the ... More
Smooth Hybrid Inflation and Non-Thermal Type II LeptogenesisAug 03 2012We consider a smooth hybrid inflation scenario based on a supersymmetric SU(2)_L x SU(2)_R x U(1)_B-L model. The Higgs triplets involved in the model play a key role in inflation as well as in explaining the observed baryon asymmetry of the universe. ... More
From $b \to s γ$ to the LSP Detection Rates in Minimal String Unification ModelsApr 04 1997We exploit the measured branching ratio for $b \rightarrow s\gamma$ to derive lower limits on the sparticle and Higgs masses in the minimal string unification models. For the LSP('bino'), chargino and the lightest Higgs, these turn out to be 50, 90 and ... More
Single Field Inflation in Supergravity with a $U(1)$ Gauge SymmetryMay 27 2015Oct 15 2015A single field inflation based on a supergravity model with a shift symmetry and $U(1)$ extension of the MSSM is analyzed. We show that one of the real components of the two $U(1)$ charged scalar fields plays the role of inflaton {with} an effective scalar ... More
Lightweight Mutual Authentication Protocol for Low Cost RFID TagsMay 25 2010Radio Frequency Identification (RFID) technology one of the most promising technologies in the field of ubiquitous computing. Indeed, RFID technology may well replace barcode technology. Although it offers many advantages over other identification systems, ... More
Large BR(h -> tau mu) in Supersymmetric ModelsMay 24 2016We analyze the Lepton Flavor Violating (LFV) Higgs decay h -> tau mu in three supersymmetric models: Minimal Supersymmetric Standard Model (MSSM), Supersymmetric Seesaw Model (SSM), and Supersymmetric B-L model with Inverse Seesaw (BLSSM-IS). We show ... More
Bound on Z' Mass from CDMS II in the Dark Left-Right Gauge Model IIFeb 03 2010With the recent possible signal of dark matter from the CDMS II experiment, the Z' mass of a new version of the dark left-right gauge model (DLRM II) is predicted to be at around a TeV. As such, it has an excellent discovery prognosis at the operating ... More
Phenomenological implications of moduli-dominant SUSY breakingMar 05 1997Jul 14 1997We study moduli-dominated SUSY breaking within the framework of string models. This type of SUSY breaking in general leads to non-universal soft masses, i.e. soft scalar masses and gaugino masses. Further gauginos are lighter than sfermions. This non-universality ... More
Aspects of moduli stabilization in type IIB string theoryOct 01 2015We review moduli stabilization in type IIB string theory compactification with fluxes. We focus on the KKLT and Large Volume Scenario (LVS). We show that the predicted soft SUSY breaking terms in KKLT model are not phenomenological viable. In LVS, the ... More
Stop_times based Routing Protocol for VANETNov 28 2013Vehicular Ad hoc Network (VANET) is a special class of Mobile Ad hoc Network (MANET) where vehicles are considered as MANET nodes with wireless links. The key difference of VANET and MANET is the special mobility pattern and rapidly changeable topology. ... More
Warm Dark Matter in B-L Inverse SeesawAug 04 2013Feb 08 2015We show that a standard model gauge singlet fermion field, with mass of order keV or larger, and involved in the inverse seesaw mechanism of light neutrino mass generation, can be a good warm dark matter candidate. Our framework is based on B-L extension ... More
Electron EDM and soft leptogenesis in supersymmetric B-L extension of the standard modelFeb 25 2009Jul 09 2009We analyze the connection between electric dipole moment of the electron and the soft leptogenesis in supersymmetric $B-L$ extension of the standard model. In this model, the $B-L$ symmetry is radiatively broken at TeV scale. Therefore, it is a natural ... More
Sparticle and Higgs masses within minimal string unificationNov 08 1996Mar 05 1997We consider the sparticle and higgs spectroscopy in a class of superstring inspired models in which the string threshold corrections ensure the consistency of the string unification scale with the low energy data. The lightest neutralino is almost a pure ... More
Like-sign dimuon charge asymmetry in Randall-Sundurm modelNov 27 2010Apr 19 2011We confirm that in order to account for the recent D\O\ result of large like-sign dimuon charge asymmetry, a considerable large new physics effect in $\Gamma_{12}^s$ is required in addition to a large CP violating phase in $B_s -\bar{B}_s$ mixing. In ... More
Lepton-Flavor Violation with Non-universal Soft TermsJan 22 2001May 09 2001We study the lepton-flavor violation processes tau ->mu gamma and mu->e gamma in two different examples of models with non-universal soft breaking terms derived from strings. We show that the predictions are quite different from those of universal scenarios. ... More
Nonzero Theta13 for Neutrino Mixing in a Supersymmetric B-L Gauge Model with T_7 Lepton Flavor SymmetryAug 02 2011Sep 13 2011We discuss how \theta_{13} \neq 0 is accommodated in a recently proposed renormalizable model of neutrino mixing using the non-Abelian discrete symmetry T_7 in the context of a supersymmetric extension of the Standard Model with gauged U(1)_{B-L}. We ... More
Light sfermion interplay in the 125 GeV MSSM Higgs production and decay at the LHCDec 06 2013Mar 19 2014We study the effects from light sfermions on the lightest Higgs boson production and decay at the Large Hadron Collider (LHC) within the Minimal Supersymmetric Standard Model (MSSM). We find that the scenario with light coloured sfermions -- stops or ... More
Signatures for right-handed neutrinos at the Large Hadron ColliderMar 19 2008Oct 29 2008We explore possible signatures for right-handed neutrinos in TeV scale B-L extension of the Standard Model (SM) at the Large Hadron Collider (LHC). The studied four lepton signal has a tiny SM background. We find the signal experimentally accessible at ... More
Neutrino Spin Flavor Precession and LeptogenesisMay 06 2012May 09 2012We argue that \Delta L=2 neutrino spin flavor precession, induced by the primordial magnetic fields, could have a significant impact on the leptogenesis process that accounts for the baryon asymmetry of the universe. Although the extra galactic magnetic ... More
Observable T_7 Lepton Flavor Symmetry at the Large Hadron ColliderSep 28 2010Mar 08 2011More often than not, models of flavor symmetry rely on the use of nonrenormalizable operators (in the guise of flavons) to accomplish the phenomenologically successful tribimaximal mixing of neutrinos. We show instead how a simple renormalizable two-parameter ... More
Gauged B-L LeptogenesisMar 01 2010We propose a new leptogenesis scenario in a gauged $B-L$ model with supersymmetry at the TeV energy scale. Instead of relying on the very small Yukawa couplings of the singlet neutrinos $N^c$ to generate the observed baryon asymmetry of the Universe, ... More
A new strategy for probing the Majorana neutrino CP violating phases and massesAug 15 2009We propose a new strategy for detecting the CP-violating phases and the effective mass of muon Majorana neutrinos by measuring observables associated with neutrino-antineutrino oscillations in $\pi^{\pm}$ decays. Within the generic framework of quantum ... More
QFT results for neutrino oscillations and New PhysicsJan 12 2009Apr 30 2009The CP asymmetry in neutrino oscillations, assuming new physics at production and/or detection processes, is analyzed. We compute this CP asymmetry using the standard quantum field theory within a general new physics scenario that may generate new sources ... More
Semi-supervised Classification: Cluster and Label Approach using Particle Swarm OptimizationJun 03 2017Classification predicts classes of objects using the knowledge learned during the training phase. This process requires learning from labeled samples. However, the labeled samples usually limited. Annotation process is annoying, tedious, expensive, and ... More
A $U(1)_R$ inspired inflation model in no-scale SupergravityOct 15 2018We consider a cosmological inflation scenario based on a no-scale supergravity sector with $U(1)_R$ symmetry. It is shown that a tree level $U(1)_R$ symmetric superpotential alone does not lead to a slowly rolling scalar potential. A deformation of this ... More
GPU-Framework for Teamwork Action RecognitionOct 12 2013Real time processing for teamwork action recognition is a challenge, due to complex computational models to achieve high system performance. Hence, this paper proposes a framework based on Graphical Processing Units (GPUs) to achieve a significant speed ... More
Predictions for $B \to τ\barμ + μ\barτ $Nov 21 2012Apr 30 2013The observation of $B \to \tau \bar{\mu} + \mu \bar{\tau} $ at present experiments would be a clear sign of new physics. In this paper we calculate this process in a 2HDM framework where the decay is mediated by the exchange of spin zero particle with ... More
Dimuon CP Asymmetry in B Decays and Wjj Excess in Two Higgs Doublet ModelsApr 27 2011We analyze the puzzle of the dimuon CP asymmetry in B_s decays in two Higgs doublet models. We show that the flavor changing neutral current (FCNC) induced by the Higgs coupling in a type III two Higgs doublet model provides a solution to the dimuon charge ... More
New Physics from Low ScalesDec 13 2018We consider several extensions of the Standard Model (SM) which can explain the anomalies observed by the Atomki collaboration in the decay of excited states of Beryllium via a new boson with a mass around 17 MeV yielding $e^+ e^-$ pairs. We show how ... More
$R_K$ and $R_{K^*}$ in an Aligned 2HDM with Right-Handed NeutrinosMar 26 2019We consider the possibility to explain the recent $R_K$ and $R_{K ^*}$ anomalies in a 2-Higgs Doublet Model, known as Aligned, combined with a low scale seesaw mechanism generating light neutrino masses and mixings. In this class of models, a large Yukawa ... More
A Computer Virus Propagation Model Using Delay Differential Equations With Probabilistic Contagion And ImmunityOct 21 2014The SIR model is used extensively in the field of epidemiology, in particular, for the analysis of communal diseases. One problem with SIR and other existing models is that they are tailored to random or Erdos type networks since they do not consider ... More
Interaction of Polar and Nonpolar Organic Pollutants with Soil Organic Matter: Sorption Experiments and Molecular Dynamics SimulationOct 08 2014The fate of organic pollutants in the environment is influenced by several factors including the type and strength of their interactions with soil components especially SOM. However, a molecular level answer to the question How organic pollutants interact ... More
On the effect of the thermal gas component to the stability of vortices in trapped Bose-Einstein condensatesMar 12 2002We study the stability of vortices in trapped single-component Bose-Einstein condensates within self-consistent mean-field theories--especially we consider the Hartree-Fock-Bogoliubov-Popov theory and its recently proposed gapless extensions. It is shown ... More
On the origin of variable gamma-ray emission from the Crab NebulaNov 08 2010Jan 31 2011The oblique geometry of pulsar wind termination shock ensures that the Doppler beaming has a strong impact on the shock emission. We illustrate this using recent relativistic MHD simulations of the Crab Nebula and also show that the observed size, shape, ... More
Anharmonic resonance absorption of short laser pulses in clusters: A molecular dynamics simulation studyDec 07 2016Linear resonance (LR) absorption of an intense 800~nm laser light in a nano-cluster requires a long laser pulse > 100~fs when Mie-plasma frequency ($\omegaMie$) of electrons in the expanding cluster matches the laser frequency~($\omega$). For a short ... More
Formation of internal shock waves in bent jetsSep 07 2001Jan 10 2002We discuss the circumstances under which the bending of a jet can generate an internal shock wave. The analysis is carried out for relativistic and non-relativistic astrophysical jets. The calculations are done by the method of characteristics for the ... More
Tearing instability in relativistic magnetically dominated plasmasJun 15 2006Jun 21 2006Many astrophysical sources of high energy emission, such as black hole magnetospheres, superstrongly magnetized neutron stars (magnetars), and probably relativistic jets in Active Galactic Nuclei and Gamma Ray Bursts involve relativistically magnetically ... More
Quantum rings for beginners II: Bosons versus fermionsOct 02 2012The purpose of this overview article, which can be viewed as a supplement to our previous review on quantum rings, [S. Viefers {\it et al}, Physica E {\bf 21} (2004), 1-35], is to highlight the differences of boson and fermion systems in one-dimensional ... More
Configuration interaction approach to the few-body problem in a two-dimensional harmonic trap with contact interactionOct 23 2008The configuration interaction (CI) method for calculating the exact eigenstates of a quantum-mechanical few-body system is problematic when applied to contact interactions between the particles. In two and three dimensions, the approach fails due to the ... More
Characterizing multipartite symmetric Dicke states under the effects of noiseMar 23 2009Jun 26 2009We study genuine multipartite entanglement (GME) in a system of $n$ qubits prepared in symmetric Dicke states and subjected to the influences of noise. We provide general, setup-independent expressions for experimentally favorable tools such as fidelity- ... More
Generalized Induced NormsJul 21 2004Let ||.|| be a norm on the algebra M_n of all n-by-n matrices over the complex field C. An interesting problem in matrix theory is that "are there two norms ||.||_1 and ||.||_2 on C^n such that ||A||=max{||Ax||_2: ||x||_1=1} for all A in M_n. We will ... More
Relative Entropy and Tsallis Entropy of two Accretive OperatorsMay 19 2017Let $A$ and $B$ be two accretive operators. We first introduce the weighted geometric mean of $A$ and $B$ together with some related properties. Afterwards, we define the relative entropy as well as the Tsallis entropy of $A$ and $B$. The present definitions ... More
Plasmon exchange model for superconductivity in Carbon nanotubesFeb 20 2004Recent investigations of superconductivity in carbon nanotubes have shown that a single-wall zigzag nanotube can become superconducting at around 15 K. Theoretical studies of superconductivity in nanotubes using the traditional phonon exchange model, ... More
Methods for studying the accuracy of light propagation in N-body simulationsJan 07 2015Aug 15 2015It is proposed to use exact, cosmologically relevant solutions to Einstein's equations to accurately quantify the precision of ray tracing techniques through Newtonian N-body simulations. As an initial example of such a study, the recipe in (Green & Wald, ... More
Studying the precision of ray tracing techniques with Szekeres modelsJun 30 2015Oct 02 2015The simplest standard ray tracing scheme employing the Born and Limber approximations and neglecting lens-lens coupling is used for computing the convergence along individual rays in mock N-body data based on Szekeres swiss cheese and onion models. The ... More
Deflection of jets induced by jet-cloud & jet-galaxy interactionsAug 01 2000Mar 31 2001The model first introduced by Raga & Canto (1996) in which astrophysical jets are deflected on passing through an isothermal high density region is generalised by taking into account gravitational effects on the motion of the jet as it crosses the high ... More
Simulating the Early Evolution of the Hard X-Ray Properties of a Young Stellar PopulationAug 05 2003We present an X-ray binary population synthesis model, and use it to simulate the evolution of X-ray binaries formed in a burst of star formation of duration 20 Myr and star-formation rate 10 M_sun/yr. Our goal is to explain the hard (2-10 keV) X-ray ... More
On charge and spin ordering in a one-dimensional model with frustrating interactionsOct 01 2005Oct 06 2005We study a one-dimensional extended Hubbard model with longer-range Coulomb interactions at quarter-filling in the strong coupling limit. We find two different charge-ordered ground states as the strength of the longer range interactions is varied. At ... More
Deflection of Jets Induced by Jet-Cloud InteractionsApr 02 2001A non--relativistic and relativistic model in which astrophysical jets are deflected on passing through an isothermal high density region is analysed. The criteria for the stability of jets due to the formation of internal shocks are discussed.
Chandra View of the Dynamically Young Cluster of Galaxies A1367 I. Small-Scale StructuresJun 14 2002The 40 ks \emph{Chandra} ACIS-S observation of A1367 provides new insights into small-scale structures and point sources in this dynamically young cluster. Here we concentrate on small-scale extended structures. A ridge-like structure around the center ... More
Investigation of quantum rouletteJul 20 2008Apr 30 2009In this paper, by using permutation matrices as a representation of symmetric group $S_N$ and Fourier matrix, we investigate quantum roulette with an arbitrary $N$-state. This strategy, which we introduce, is general method that allows us to solve quantum ... More
Electron correlation in metal clusters, quantum dots and quantum ringsOct 15 2008This short review presents a few case studies of finite electron systems for which strong correlations play a dominant role. In simple metal clusters, the valence electrons determine stability and shape of the clusters. The ionic skeleton of alkali metals ... More
Metal clusters, quantum dots and trapped atoms -- from single-particle models to correlatioMar 12 2007In this review, we discuss the electronic structure of finite quantal systems on the nanoscale. After a few general remarks on the many-particle physics of the harmonic oscillator -- likely being the most studied example for the many-body systems of finite ... More