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Y. N. Srivastava

Publications and source records attributed to Y. N. Srivastava.

At least 73 records · Page 4Linked to original sources
arXiv2008

Zero momentum gluons and the total pp and pbarp cross-sections

We describe a QCD motivated model for total cross-sections which uses the eikonal representation and incorporates QCD mini-jets to drive the rise with energy of the cross-section, while the impact parameter distribution is obtained through the Fourier transform of the transverse momentum distribution of soft gluons emitted in the parton-parton interactions giving rise to mini-jets in the final state. A singular but integral expression for the running coupling constant in the infrared region is part of this model.

hep-ph↗
arXiv2008

A Primer for Electro-Weak Induced Low Energy Nuclear Reactions

In a series of papers, cited in the main body of the paper below, detailed calculations have been presented which show that electromagnetic and weak interactions can induce low energy nuclear reactions to occur with observable rates for a variety of processes. A common element in all these applications is that the electromagnetic energy stored in many relatively slow moving electrons can -under appropriate circumstances- be collectively transferred into fewer, much faster electrons with energies sufficient for the latter to combine with protons (or deuterons, if present) to produce neutrons via weak interactions. The produced neutrons can then initiate low energy nuclear reactions through further nuclear transmutations. The aim of this paper is to extend and enlarge upon various examples analyzed previously, present simplified order of magnitude estimates for each and to illuminate a common unifying theme amongst all of them.

nucl-th↗
arXiv2008

QCD Contributions to the Froissart bound for the total cross-section

We discuss the effect of infrared soft gluons on the asymptotic behaviour of the total cross-section. We use a singular but integrable expression for the strong coupling constant in the infrared limit and relate its behaviour to the satisfaction of the Froissart bound, giving a specific phenomenological example.

hep-ph↗
arXiv2008

High Energy Particles in the Solar Corona

Collective Ampere law interactions producing magnetic flux tubes piercing through sunspots into and then out of the solar corona allow for low energy nuclear reactions in a steady state and high energy particle reactions if a magnetic flux tube explodes in a violent event such as a solar flare. Filamentous flux tubes themselves are vortices of Ampere currents circulating around in a tornado fashion in a roughly cylindrical geometry. The magnetic field lines are parallel to and largely confined within the core of the vortex. The vortices may thereby be viewed as long current carrying coils surrounding magnetic flux and subject to inductive Faraday and Ampere laws. These laws set the energy scales of (i) low energy solar nuclear reactions which may regularly occur and (ii) high energy electro-weak interactions which occur when magnetic flux coils explode into violent episodic events such as solar flares or coronal mass ejections.

nucl-th↗
arXiv2008

Minijets, soft gluon resummation and photon cross-sections

We compare the high energy behaviour of hadronic photon-photon cross-sections in different models. We find that the photon-photon cross-section appears to rise faster than the purely hadronic ones (proton-proton and proton-antiproton).

hep-ph↗
arXiv2008

Errors in the Quantum Electrodynamic Mass Analysis of Hagelstein and Chaudhary

Hagelstein and Chaudhary have recently criticized our low energy nuclear reaction rates in chemical cells based on our computed electron mass renormalization for surface electrons of metal hydride electrodes. They further criticize our electron mass renormalization in exploding wire systems which is very strange because mass renormalization was {\em never even mentioned} in our exploding wire work. Here we show that the calculations of Hagelstein and Chaudhary are erroneous in that they are in conflict with the Gauss law, i.e. they have arbitrarily removed all Coulomb interactions in electromagnetic propagators. They have also ignored substantial Ampere interactions in favor of computing only totally negligible contributions. When the fallacious considerations of Hagelstein and Chaudhary are clearly exposed, it becomes evident that our previous calculations remain valid.

quant-ph↗
arXiv2008

Large rapidity gaps survival probabilities at LHC

We calculate the probability of large rapidity gaps in high energy hadronic collisions using a model based on QCD mini-jets and soft gluon emission down into the infrared region. Comparing with other models we find a remarkable agreement among most predictions.

hep-ph↗
arXiv2007

Magnetoelectric Effects on Composite Nano Granular $Fe/TiO_{2-δ}$ Films

Employing a new experimental technique to measure magnetoelectric response functions, we have measured the magnetoelectric effect in composite films of nano granular metallic iron in anatase titanium dioxide at temperatures below 50 K. A magnetoelectric resistance is defined as the ratio of a transverse voltage to bias current as a function of the magnetic field. In contrast to the anomalous Hall resistance measured above 50 K, the magnetoelectic resistance below 50 K is significantly larger and exhibits an even symmetry with respect to magnetic field reversal $H\to -H$. The measurement technique required attached electrodes in the plane of the film composite in order to measure voltage as a function of bias current and external magnetic field. To our knowledge, the composite films are unique in terms of showing magnetoelectric effects at low temperatures, $<$ 50 K, and anomalous Hall effects at high temperatures, $>$ 50 K.

cond-mat.mtrl-sci↗
arXiv2007

Klein Paradox for Optical Scattering from Excited Targets

The well known Klein paradox for the relativistic Dirac wave equation consists in the computation of possible ``negative probabilities'' induced by certain potentials in some regimes of energy. The paradox may be resolved employing the notion of electron-positron pair production in which the number of electrons present in a process can increase. The Klein paradox also exists in Maxwell's equations viewed as the wave equation for photons. In a medium containing ``inverted energy populations'' of excited atoms, e.g. in a LASER medium, one may again compute possible ``negative probabilities''. The resolution of the electromagnetic Klein paradox is that when the atoms decay, the final state may contain more photons then were contained the initial state. The optical theorem total cross section for scattering photons from excited state atoms may then be computed as negative within a frequency band with matter induced amplification.

quant-ph↗
arXiv2007

Energetic Electrons and Nuclear Transmutations in Exploding Wires

Nuclear transmutations and fast neutrons have been observed to emerge from large electrical current pulses passing through wire filaments which are induced to explode. The nuclear reactions may be explained as inverse beta transitions of energetic electrons absorbed either directly by single protons in Hydrogen or by protons embedded in other more massive nuclei. The critical energy transformations to the electrons from the electromagnetic field and from the electrons to the nuclei are best understood in terms of coherent collective motions of the many flowing electrons within a wire filament. Energy transformation mechanisms have thus been found which settle a theoretical paradox in low energy nuclear reactions which has remained unresolved for over eight decades. It is presently clear that nuclear transmutations can occur under a much wider range of physical conditions than was heretofore thought possible.

nucl-th↗
arXiv2007

Is the Pentaquark the Only Justification for Research on KN Physics ?

The talk is intended to motivate the use of DA$Φ$NE--2 running at the $ϕ$ peak as an intense, clean source of low--momentum charged and neutral kaons. It covers a few open problems still unsolved after more than twenty--five years and the physics (some of it still novel) that could be learned only in this way. And, of course, the answer to the above question is {\sl NO}.

nucl-th↗
arXiv2007

Viscosity of High Energy Nuclear Fluids

Relativistic high energy heavy ion collision cross sections have been interpreted in terms of almost ideal liquid droplets of nuclear matter. The experimental low viscosity of these nuclear fluids have been of considerable recent quantum chromodynamic interest. The viscosity is here discussed in terms of the string fragmentation models wherein the temperature dependence of the nuclear fluid viscosity obeys the Vogel-Fulcher-Tammann law.

nucl-th↗
arXiv2006

Fractal Propagators in QED and QCD and Implications for the Problem of Confinement

We show that QED radiative corrections change the propagator of a charged Dirac particle so that it acquires a fractional anomalous exponent connected with the fine structure constant. The result is a nonlocal object which represents a particle with a roughened trajectory whose fractal dimension can be calculated. This represents a significant shift from the traditional Wigner notions of asymptotic states with sharp well-defined masses. Non-abelian long-range fields are more difficult to handle, but we are able to calculate the effects due to Newtonian gravitational corrections. We suggest a new approach to confinement in QCD based on a particle trajectory acquiring a fractal dimension which goes to zero in the infrared as a consequence of self-interaction, representing a particle which, in the infrared limit, cannot propagate.

hep-th↗
arXiv2006

Dynamic Time Scales in Colored Glass Nuclear Matter

In Ultra high energy collisions, the concept of a glass law is invoked in the framework of 'low tension' QCD strings. It is shown that the excitation of QCD strings at low energy has a negative temperature and at high energy has a positive temperature always higher than the Hagedorn temperature, T_H. Very high energy strings T->T_H + 0+ move very slowly as a viscous melted glass with very high viscosity. However, in a very short collision time, it is difficult to transfer the initial collision kinetic energy into the internal energy of a few strings. The low energy strings at high T>>T_H have a low viscosity giving rise to an almost perfect fluid. The role of strings in a nucleus is closely analogous to the role of polymer chains in some viscous glass beads.

nucl-th↗
arXiv2006

Total cross sections and soft gluon resummation

We discuss a model for total hadronic and photonic cross-sections which includes hard parton-parton scattering to drive the rise and soft gluon resummation to tame it. Unitarity is ensured by embedding the cross-section in the eikonal formalism. Predictions for LHC and ILC are presented.

hep-ph↗
arXiv2006

Low-Energy Kaon-Nucleus Interactions at a ϕ-Factory

Scattering and formation experiments can be performed not only with particle beams, but also, as of old, with particle sources. DA\PhiNE at the c.m. energy of the ϕis a relatively clean source of low-momentum charged and neutral kaons. As such, it can allow experiments unthinkable of at conventional kaon beams. This talk is dedicated to a presentation both of this viewpoint and of the physics that could be learned in this way.

nucl-th↗
arXiv2005

Two-Time Correlation Functions: Stochastic and Conventional Quantum Mechanics

An investigation of two-time correlation functions is reported within the framework of (i) Stochastic Quantum Mechanics and (ii) conventional Heisenberg-Schrödinger Quantum Mechanics. The spectral functions associated with the two-time electric dipole correlation functions are worked out in detail for the case of the hydrogen atom. While the single time averages are identical for stochastic and conventional quantum mechanics, differences arise in the two approaches for multiple time correlation functions.

quant-ph↗