The Limits on Unstable Heavy Particles

1980 ◽  
pp. 33-37
Author(s):  
Paul Frampton
Keyword(s):  
Heavy Particles

РАДИАЦИОННО СТОЙКОЕ КМОП СТАТИЧЕСКОЕ ОЗУ 16 МБИТ 1657РУ2У

2020 ◽  
Vol 96 (3s) ◽  
pp. 169-174
Author(s):  
Ю.М. Герасимов ◽  
Н.Г. Григорьев ◽  
А.В. Кобыляцкий ◽  
Я.Я. Петричкович
Keyword(s):  
Total Dose ◽  
Heavy Particles ◽  
Topological Features ◽  
Radiation Hardened ◽  
Latch Up

Рассматриваются архитектурные, схемотехнические и конструктивно-топологические особенности асинхронного радиационно стойкого ОЗУ 1657РУ2У емкостью 16 Мбит с организацией (1Мx16)/(2Mx8), изготавливаемого по коммерческой КМОП-технологии объемного кремния уровня 130 нм. СБИС ОЗУ нечувствительна к эффекту «защелкивания», имеет повышенные дозовую стойкость и сбоеустойчивость при воздействии отдельных ядерных частиц (ОЯЧ), протонов и нейтронов (ТЧ). The paper highlights architectural, schematic and topological features of the radiation hardened 16 Mbit CMOS SRAM with configurable organization 1Mx16/2Mx8, which is immune to latch-up and with improved total dose and heavy particles tolerance.

scholarly journals Settling Velocity of Microplastics Exposed to Wave Action

2021 ◽  
Vol 9 (2) ◽  
pp. 142
Author(s):  
Annalisa De Leo ◽  
Laura Cutroneo ◽  
Damien Sous ◽  
Alessandro Stocchino
Keyword(s):  
Laboratory Experiments ◽  
Settling Velocity ◽  
Transport Model ◽  
Stokes Drift ◽  
Inertial Effects ◽  
Sea Waves ◽  
Heavy Particles ◽  
Analytical Formulation ◽  
Simplified Approach ◽  
Remote Areas

Microplastic (MP) debris is recognized to be one of the most serious threats to marine environments. They are found in all seas and oceanic basins worldwide, even in the most remote areas. This is further proof that the transport of MPs is very efficient. In the present study, we focus our attention on MPs’ transport owing to the Stokes drift generated by sea waves. Recent studies have shown that the interaction between heavy particles and Stokes drift leads to unexpected phenomena mostly related to inertial effects. We perform a series of laboratory experiments with the aim to directly measure MPs’ trajectories under different wave conditions. The main objective is to quantify the inertial effect and, ultimately, suggest a new analytical formulation for the net settling velocity. The latter formula might be implemented in a larger scale transport model in order to account for inertial effects in a simplified approach.

scholarly journals The scalar chemical potential in cosmological collider physics

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Arushi Bodas ◽  
Soubhik Kumar ◽  
Raman Sundrum
Keyword(s):  
Particle Production ◽  
Chemical Potential ◽  
Direct Detection ◽  
Heavy Particle ◽  
Scalar Particle ◽  
Energy Scale ◽  
Fine Tuning ◽  
Tree Level ◽  
Heavy Particles ◽  
Non Gaussian

Abstract Non-analyticity in co-moving momenta within the non-Gaussian bispectrum is a distinctive sign of on-shell particle production during inflation, presenting a unique opportunity for the “direct detection” of particles with masses as large as the inflationary Hubble scale (H). However, the strength of such non-analyticity ordinarily drops exponentially by a Boltzmann-like factor as masses exceed H. In this paper, we study an exception provided by a dimension-5 derivative coupling of the inflaton to heavy-particle currents, applying it specifically to the case of two real scalars. The operator has a “chemical potential” form, which harnesses the large kinetic energy scale of the inflaton, $$ {\overset{\cdot }{\phi}}_0^{1/2}\approx 60H $$ ϕ ⋅ 0 1 / 2 ≈ 60 H , to act as an efficient source of scalar particle production. Derivative couplings of inflaton ensure radiative stability of the slow-roll potential, which in turn maintains (approximate) scale-invariance of the inflationary correlations. We show that a signal not suffering Boltzmann suppression can be obtained in the bispectrum with strength fNL ∼ $$ \mathcal{O} $$ O (0.01–10) for an extended range of scalar masses $$ \lesssim {\overset{\cdot }{\phi}}_0^{1/2} $$ ≲ ϕ ⋅ 0 1 / 2 , potentially as high as 1015 GeV, within the sensitivity of upcoming LSS and more futuristic 21-cm experiments. The mechanism does not invoke any particular fine-tuning of parameters or breakdown of perturbation-theoretic control. The leading contribution appears at tree-level, which makes the calculation analytically tractable and removes the loop-suppression as compared to earlier chemical potential studies of non-zero spins. The steady particle production allows us to infer the effective mass of the heavy particles and the chemical potential from the variation in bispectrum oscillations as a function of co-moving momenta. Our analysis sets the stage for generalization to heavy bosons with non-zero spin.

scholarly journals Fast Vacuum Fluctuations and the Emergence of Quantum Mechanics

2021 ◽  
Vol 51 (3) ◽  
Author(s):  
Gerard ’t Hooft
Keyword(s):  
Quantum Mechanics ◽  
Ground State ◽  
Quantum Interference ◽  
Direct Detection ◽  
Energy Levels ◽  
Vacuum Fluctuations ◽  
Heavy Particles ◽  
Evolving Systems ◽  
Gedanken Experiment ◽  
Classical Computer

AbstractFast moving classical variables can generate quantum mechanical behavior. We demonstrate how this can happen in a model. The key point is that in classically (ontologically) evolving systems one can still define a conserved quantum energy. For the fast variables, the energy levels are far separated, such that one may assume these variables to stay in their ground state. This forces them to be entangled, so that, consequently, the slow variables are entangled as well. The fast variables could be the vacuum fluctuations caused by unknown super heavy particles. The emerging quantum effects in the light particles are expressed by a Hamiltonian that can have almost any form. The entire system is ontological, and yet allows one to generate interference effects in computer models. This seemed to lead to an inexplicable paradox, which is now resolved: exactly what happens in our models if we run a quantum interference experiment in a classical computer is explained. The restriction that very fast variables stay predominantly in their ground state appears to be due to smearing of the physical states in the time direction, preventing their direct detection. Discussions are added of the emergence of quantum mechanics, and the ontology of an EPR/Bell Gedanken experiment.

scholarly journals On the nature of protostellar H2O masers

1987 ◽  
Vol 122 ◽  
pp. 141-142
Author(s):  
G. M. Rudnitskij
Keyword(s):  
Active Phase ◽  
Young Star ◽  
Line Profiles ◽  
Free Electrons ◽  
Heavy Particles ◽  
Vlbi Observations ◽  
Generation Region ◽  
Star Formation Regions ◽  
Maser Radio ◽  
Two Temperature

Most sources of B2O maser radio emission at 1.35 cm, associated with star formation regions, show strong variability with, sometimes, rapid bursts of emission (see, e.g., Liljeström 1984, Rowland and Cohen 1986, and references therein). A preliminary conclusion on the possible cyclicity of H2O maser variability can be drawn (Lekht et al. 1982, 1983), with a quasiperiod of several years. The “quiet” state of a maser source, with moderate, slowly varying values of the line flux density, turns to the “active” phase with H2O line bursts (Lekht et al. 1983). The H2O maser generation region is probably located in a rotating gas-and-dust disc (torus) around a protostar (or young star). This is pointed to by VLBI observations showing in some sources maser features arranged in an ellipsoidal structure around a common centre (presumably, the protostellar object - see Downes et al. 1979), as well as by symmetrical character of E2O line profiles of many masers (Lekht et al. 1982). As an excitation mechanism for H2O, collisional pumping in two-temperature medium behind a shock front (with hot heavy particles and cold free electrons or vice versa) is widely accepted (Bolgova et al. 1982, Kylafis and Norman 1986).

scholarly journals Search for new heavy particles decaying toZZ→llll,lljjinpp¯collisions ats=1.96  TeV

2011 ◽  
Vol 83 (11) ◽  
Author(s):  
T. Aaltonen ◽  
B. Álvarez González ◽  
S. Amerio ◽  
D. Amidei ◽  
A. Anastassov ◽  
...  
Keyword(s):  
Heavy Particles

scholarly journals Flavour anomalies from a split dark sector

2020 ◽  
Vol 2020 (8) ◽  
Author(s):  
Luc Darmé ◽  
Marco Fedele ◽  
Kamila Kowalska ◽  
Enrico Maria Sessolo
Keyword(s):  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Mass Scale ◽  
Resonance Structure ◽  
Meson Mass ◽  
Dark Sector ◽  
Missing Energy ◽  
Effective Coupling ◽  
Heavy Particles ◽  
Near Future

Abstract We investigate solutions to the flavour anomalies in B decays based on loop diagrams of a “split” dark sector characterised by the simultaneous presence of heavy particles at the TeV scale and light particles around and below the B-meson mass scale. We show that viable parameter space exists for solutions based on penguin diagrams with a vector mediator, while minimal constructions relying on box diagrams are in strong tension with the constraints from the LHC, LEP, and the anomalous magnetic moment of the muon. In particular, we highlight a regime where the mediator lies close to the B-meson mass, naturally realising a resonance structure and a q2-dependent effective coupling. We perform a full fit to the relevant flavour observables and analyse the constraints from intensity frontier experiments. Besides new measurements of the anomalous magnetic moment of the muon, we find that decays of the B meson, Bs-mixing, missing energy searches at Belle-II, and LHC searches for top/bottom partners can robustly test these scenarios in the near future.

scholarly journals Inertial-particle accelerations in turbulence: a Lagrangian closure

2016 ◽  
Vol 798 ◽  
pp. 187-200 ◽  
Author(s):  
S. Vajedi ◽  
K. Gustavsson ◽  
B. Mehlig ◽  
L. Biferale
Keyword(s):  
Numerical Simulations ◽  
Numerical Data ◽  
Direct Numerical Simulations ◽  
Inertial Particles ◽  
Inertial Particle ◽  
Order Unity ◽  
Heavy Particles ◽  
Preferential Sampling ◽  
Closure Scheme ◽  
Light Particles

The distribution of particle accelerations in turbulence is intermittent, with non-Gaussian tails that are quite different for light and heavy particles. In this article we analyse a closure scheme for the acceleration fluctuations of light and heavy inertial particles in turbulence, formulated in terms of Lagrangian correlation functions of fluid tracers. We compute the variance and the flatness of inertial-particle accelerations and we discuss their dependency on the Stokes number. The closure incorporates effects induced by the Lagrangian correlations along the trajectories of fluid tracers, and its predictions agree well with results of direct numerical simulations of inertial particles in turbulence, provided that the effects induced by inertial preferential sampling of heavy/light particles outside/inside vortices are negligible. In particular, the scheme predicts the correct functional behaviour of the acceleration variance, as a function of $St$, as well as the presence of a minimum/maximum for the flatness of the acceleration of heavy/light particles, in good qualitative agreement with numerical data. We also show that the closure works well when applied to the Lagrangian evolution of particles using a stochastic surrogate for the underlying Eulerian velocity field. Our results support the conclusion that there exist important contributions to the statistics of the acceleration of inertial particles independent of the preferential sampling. For heavy particles we observe deviations between the predictions of the closure scheme and direct numerical simulations, at Stokes numbers of order unity. For light particles the deviation occurs for larger Stokes numbers.

scholarly journals Numerical simulation of the accumulation of heavy particles in a circular bounded vortex flow

2016 ◽  
Vol 87 ◽  
pp. 80-89 ◽  
Author(s):  
Xiaoke Ku ◽  
Jianzhong Lin ◽  
Martin van Sint Annaland ◽  
Rob Hagmeijer
Keyword(s):  
Numerical Simulation ◽  
Vortex Flow ◽  
Heavy Particles

Some experimental results on W-values for heavy particles

1978 ◽  
Vol 23 (6) ◽  
pp. 1197-1199 ◽  
Author(s):  
M Chemtob ◽  
N Parmentier ◽  
V D Nguyen
Keyword(s):  
Experimental Results ◽  
Heavy Particles
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