120262865
On the various aspects of interacting Ricci dark energy and tachyonic field
In this letter we considered an interaction between Ricci dark energy and tachyonic field. We investigated the equation of state parameters in presence of the interaction and revealed a quintessence like behavior. Also, we investigated the validity of the generalized second law of thermodynamics in presence of this interaction and observed that it is broken down under this interaction.
121538545
Interacting Ricci dark energy in scalar Gauss-Bonnet gravity
Abstract.This paper reports a study on the cosmological application of interacting Ricci Dark Energy (RDE) density in the scalar Gauss-Bonnet framework. The interacting holographic RDE model has been employed to obtain the equation of state (EoS) in a spatially flat universe. The main results of this paper are that the reconstructed potential of scalar Gauss-Bonnet gravity for the interacting RDE model decays with the evolution of the universe. However, it is an increasing function of the scalar field $ \phi$ . Both the strong and weak energy conditions are violated. A phantom-like behavior of the EoS parameter has been obtained. The effective EoS parameter $ \omega_{eff}$ stays below -1 but tends to -1 with the evolution of the universe. However, it cannot cross the phantom boundary. Finally, the interacting RDE model in Gauss-Bonnet gravity gives accelerated expansion of the universe.
119137152
Power Law and Logarithmic Ricci Dark Energy Models in Hořava-Lifshitz Cosmology
In this work, we studied the Power Law and the Logarithmic Entropy Corrected versions of the Ricci Dark Energy (RDE) model in a spatially non-flat universe and in the framework of Hořava-Lifshitz cosmology. For the two cases containing non-interacting and interacting RDE and Dark Matter (DM), we obtained the exact differential equation that determines the evolutionary form of the RDE energy density. Moreover, we obtained the expressions of the deceleration parameter q and, using a parametrization of the equation of state (EoS) parameter ωD given by the relation ωD(z) = ω0+ω1z, we derived the expressions of both ω0 and ω1. We interestingly found that the expression of ω0 is the same for both non-interacting and interacting case. The expression of ω1 for the interacting case has strong dependence from the interacting parameter b2. The parameters derived in this work are done in small redshift approximation and for low redshift expansion of the EoS parameter.
118578998
Interaction Between DBI-Essence and Other Dark Energies
The present work considers interaction between DBI-essence and other candidates of dark energies like modified Chaplygin gas, hessence, tachyonic field, and new agegraphic dark energy. The potentials of the fields have been reconstructed under interaction and their evolutions have been viewed against cosmic time t and scalar field φ. Equation of state parameters have also been obtained. The nature of potentials and the equation of state parameters of the dark energies have been found graphically in presence of interaction (both small and large interaction).
119797547
New Agegraphic Dark Energy model in chameleon Brans-Dicke cosmology for different forms of the scale factor
In this work, we study the New Agegraphic Dark Energy (NADE) model (which contains the conformal time η as infrared cut-off) in the framework of Brans-Dicke cosmology with chameleon scalar field which is non-minimally coupled to the matter field. Considering interacting Dark Energy and Dark Matter (DM), we calculate some relevant cosmological parameters, i.e. the equation of state (EoS) parameter, the deceleration parameter q and the evolution of the energy density parameter $\varOmega_{D}'$ for different forms of scale factors, i.e. the power-law, the emergent, the intermediate and the logamediate ones, which leads to different expressions of η.
62820584
Correspondence between f(G) gravity and holographic dark energy via power-law solution
In this paper, we discuss cosmological application of holographic Dark Energy (HDE) in the framework of f(G) modified gravity. For this purpose, we construct f(G) model with the inclusion of HDE and a well-known power law form of the scale factor a(t). The reconstructed f(G) is found to satisfy a sufficient condition for a realistic modified gravity model. We find quintessence behavior of effective equation of state (EoS) parameter ωDE through energy conditions in this context. Moreover, we observe that the squared speed of sound $v_{s}^{2}$ remains negative, which indicates the instability of HDE f(G) model.
121605686
Anomalous increase in width of fission fragment mass distribution inF19+Th232
Fission fragment mass distribution has been studied for the system $^{19}\mathrm{F}+^{232}\mathrm{Th}$ over an energy range of $105.4\phantom{\rule{0.3em}{0ex}}\text{MeV}$ to $84.2\phantom{\rule{0.3em}{0ex}}\text{MeV}$ in laboratory frame. For energies, above the Coulomb barrier, the variance of the mass distributions ${\ensuremath{\sigma}}_{m}^{2}$ varies linearly with temperature of the fused system, signifying statistical fusion-fission reaction. However, as energy decreases through the Coulomb barrier, a rapid increase in ${\ensuremath{\sigma}}_{m}^{2}$ is observed for the first time which may be a signal of onset of orientation dependent quasifission reaction.
54674221
CALCULATION OF COLLECTIVE EFFECTS AND BEAM LIFETIMES FOR THE LBL 1-2 GeV SYNCHROTRON RADIATION SOURCE
In designing a third-generation high brightness synchrotron radiation source, attention must be paid to the various collective effects that can influence beam performance. We report on calculations, performed with the code ZAP, of the bunch length, the transverse emittance and the beam lifetime (from both Touschek and gas scattering) for our l-2 GeV storage ring. In addition, we estimate the growth times for both longitudinal and transverse coupled bunch instabilities. Bunch lengths of about 20 ps should be obtainable and intrabeam scattering emittance growth is small. For a limiting undulator gap of 1 cm and residual gas pressure of 1 nTorr, the beam lifetime is about 5 hours in the single-bunch mode; in the multibunch mode, lifetimes in excess of 6 hours are expected. These results indicate that all performance goals for the facility should be achievable. prototype Light Source vacuum chamber, we expect the broadband impedance contributed by the vacuum chamber itself to be much smaller than 1 Z,, /n 1 = 2Q. based on user requirements, are as follows:1 nominal beam energy of 1.5 GeV with an energy range 0.75-1.9 GeV, average beam current of 400 mA in the multibunch configuration and 7.6 mA for the single bunch option, horizontal rms emittance less than IO-8 m-rad, rms bunch lengths of lo-25 ps and beam lifetime of at least 6 hours. In this paper, we examine the lattice that was selected to meet these requirements in terms of collective effects that can influence machine performance. First, we discuss the various estimated beam-storage-ring coupling impedances. This allows us to calculate the expected bunch lengths obtainable in the ring, limited by single-bunch instabilities. Effects of coupled bunch instabilities (growth rates and frequency shifts) aie then calculated. The dense beam bunches specified for the Light Source make it necessary to estimate the possible growth in beam emittance due to intrabeam scattering (16s). Calculations confirm that this phenomenon is unimportant at high energies. Finally, we estimate the beam lifetime, taking into account the combined effects of Touschek and gas scattering. All of the calculations reported here were performed with the LBL accelerator physics code ZAP.* Coupling Impedances Many elements in the Light Source storage ring will contribute to the beam-storage-ring coupling impedance. The narrow-band, high-Q impedances arise primarily from the rf cavities, through their higher order modes. These can potentially induce coupled bunch coherent modes. The shunt impedances, resonant frequencies and quality factors for the higher modes of the Light Source rf cavity are taken from experimental observations and calculations for the 500 MHz KEK rf cavity with undamped modes.5 The broadband, low-Q impedance arises from the vacuum chamber itself, together with other elements such as diagnostic instruments, bellows, etc., and the equivalent broadband impedance arising from the many rf cavity modes. This latter rf-equivalent broadband impedance is taken to he 0.2512 per rf cell, as obtained by appropriate summing of the higher order modes of the KEK cavity.5 A detailed impedance inventory has clot been performed yet; however, based on preliminary laboratory measurements4 of the
102345903
Advances in beam physics and technology: Colliders of the future
Beams may be viewed as directed and focussed flow of energy and information, carried by particles and electromagnetic radiation fields (i.e. photons). Often, they are brought into interaction with each other (e.g. in high energy colliders) or with other forms of matter (e.g. in fixed target physics, synchrotron radiation sciences, neutron scattering experiments, laser chemistry and physics, medical therapy, etc.). The whole art and science of beams revolve around the fundamental quest for, and ultimate implementation of, mechanisms of production, storage, control and observation of beams—always directed towards studies of the basic structures and processes of the natural world and various practical applications. Tremendous progress has been made in all aspects of beam physics and technology in the last decades—nonlinear dynamics, superconducting magnets and radio frequency cavities, beam instrumentation and control, novel concepts and collider paradigms, to name a few. We will illustrate this progress via...
122716684
Chapter 12: Beam Instabilities
A method and a related electronic device for selecting, from a plurality of candidate video frame sets, a candidate video frame set to be inserted in a video frame slot of a given video content. It comprises obtaining the plurality of candidate video frame sets according to ranking values of a sorting parameter associated with each of the candidate video frame sets, thereby obtaining a list of candidate video frame sets and for each candidate video frame set of the list, determining a processing cost for inserting the candidate video frame set and applying the processing cost for obtaining an updated candidate video frame set ranking value according to the sorting parameter. The list is then sorted according to the updated ranking values of the sorting parameter and a selection of a candidate video frame set of the sorted list according to the updated ranking value.
55301223
Theory and analysis of nonlinear dynamics and stability in storage rings: a working group summary
LBL-25580 Lawrence Berkeley Laboratory UNIVERSITY OF CALIFORNIA Accelerator & Fusion Research Division Presented at the Second ICFA Advanced Beam Dynamics Workshop on ApertureLimitations in Storage Rings, Lugano, Switzerland, April 11-16, 1988 Theory and Analysis of Nonlinear Dynamics and Stability in Storage Rings-A Workip.g Group Summary S. Chattopadhyay, P.Audy; E .D. Courant, E. Forest, G. Guignard, J; Hagel, S. Heifets, E. Keil, S. Kheifets, H. Mais, H. Moshammer, C. Pellegrilli, F. Pilat, T. Suzuki, G. Turchetti, and R.L. Warnock July 1988 !i Prepared for the U.s. Department of Energy under Contract Number DEhCO~.76SFO0098.