56025204
A Dark Energy Model with Generalized Uncertainty Principle in the Emergent, Intermediate and Logamediate Scenarios of the Universe
This work is motivated by the work of Kim et al. (Mod. Phys. Lett. A 23:3049, 2008), which considered the equation of state parameter for the new agegraphic dark energy based on generalized uncertainty principle coexisting with dark matter without interaction. In this work, we have considered the same dark energy interacting with dark matter in emergent, intermediate and logamediate scenarios of the universe. Also, we have investigated the statefinder, kerk and lerk parameters in all three scenarios under this interaction. The energy density and pressure for the new agegraphic dark energy based on generalized uncertainty principle have been calculated and their behaviors have been investigated. The evolution of the equation of state parameter has been analyzed in the interacting and non-interacting situations in all the three scenarios. The graphical analysis shows that the dark energy behaves like quintessence era for logamediate expansion and phantom era for emergent and intermediate expansions of the universe.
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.
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.
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).
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.
25614674
On stochastic cooling of bunches in the colliding beam mode in high energy p-p storage rings
Possible cooling rates for stochastic cooling of intense bunches of protons and antiprotons in the colliding beam mode in the Fermilab Tevatron and the CERN SPS pp colliders are estimated, based solely on the bandwidth of the cooling system and the phase-space structure of the bunches and found to be a few tens of hours for high frequency large bandwidth feedback systems typically in the 8-16 GHz range and higher. The feasibility of even such slow cooling schemes, will depend on successful design of pick-ups, kickers and novel signal processing schemes in this high frequency regime, all of which demand detailed study.
55170058
EMERGING CONCEPTS, TECHNOLOGIES AND OPPORTUNITIES FOR MEZZO-SCALE TERAHERTZ AND INFRARED FACILITIES *
Recent advances in high-current particle beam, bright photoinjector, laser and radiofrequency technologies, combined with innovative techniques such as energy recovery and laser-slicing of particle beams, have opened up new scientific opportunities with terahertz and infrared sources. They present new scientific frontiers not just in sources but in basic research applications involving timescale measurements and investigations at the quantum level. Such long-wavelength sources complement high-energy, short-wavelength x-ray sources by allowing collective processes and their ‘function’ in complex systems to be probed in a fashion complementary to probing ‘structure’ via x-rays. This paper outlines and gives examples of the scientific reach of such sources and discusses some actual and envisioned facilities worldwide. Such facilities fall in the mezzoscale category, bracketed by tabletop lasers and large synchrotrons. They offer unique and directed advances in life, materials and other sciences.
56570721
Study on a test of optical stochastic cooling scheme in a single pass beam line
A feasibility study of an experiment to test the principle of optical stochastic cooling is presented. We propose to build a new beamline in the extraction area of the ALS Booster synchrotron, where we will include a bypass lattice similar to the lattice that could be used in the cooling insertion in a storage ring. Of course, in the single pass beamline we cannot achieve cooling, but we can test all the functions of the bypass lattice that are required to achieve cooling in a storage ring. As it is stated in, there are stringent requirements on the time-of-flight properties of the bypass lattice employed in a cooling scheme. The pathlengths of particle trajectories in the bypass must be fairly insensitive to the standard set of errors that usually affect the performance of storage rings. Namely, it is necessary to preserve all fluctuations in the longitudinal particle density within the beam from the beginning to the end of the bypass lattice with the accuracy of {lambda}/2{pi}, where A is the carrying (optical) wavelength. According to, cooling will completely vanish if a combined effect of all kinds of errors will produce a spread of the pathlengths of particle trajectories larger than {lambda}/2 and the cooling time will almost double if the spread of the pathlengths is {lambda}/2{pi}. At a first glance, {lambda}/2{pi} {approx_equal} 0.1/{mu}m is such a small value that satisfying this accuracy looks nearly impossible. However, simulations show that a carefully designed bypass can meet all the requirements even with rather conservative tolerance to errors.
111018506
THE CEBAF ENERGY RECOVERY EXPERIMENT: UPDATE AND FUTURE PLANS ∗
A successful GeV scale energy recovery demonstration with a high ratio of peak-to-injection energies (50:1) was carried out on the CEBAF (Continuous Electron Beam Accelerator Facility) recirculating superconducting linear accelerator in the spring of 2003. To gain a quantitative understanding of the beam behavior through the machine, data was taken to characterize the 6D phase space during the CEBAF-ER (CEBAF with Energy Recovery) experimental run. The transverse emittance of the accelerating and energy recovered beams was measured in several locations to ascertain the beam quality preservation during energy recovery. Measurements also included the RF system’s response to the energy recovery process and transverse beam profile of the energy recovered beam. One of the salient conclusions from the experiment is that the energy recovery process does not contribute significantly to the emittance degradation. The current status of the data analysis will be presented as well as plans for a GeV scale energy recovery experimental run with current doubling.
55751567
Designs for a Linac-Ring LHeC
We consider three scenarios for the recirculating electron linear accelerator (RLA) of a linac-ring type electron-proton collider based on the LHC (LHeC): (i) a pulsed linac with a final beam energy of 60 GeV ['p-60'], (ii) a higher luminosity configuration with two cw linacs and energy-recovery (ERL) also at 60 GeV ['erl'], and (iii) a high energy option using a pulsed linac with 140-GeV final energy ['p-140']. We discuss parameters, synchrotron radiation, footprints, and performance for the three scenarios.