Results 71 to 80 of about 243,233 (254)

Observation of extragalactic sources of very high energy gamma-rays with the MAGIC telescope

, 2007
MAGIC is currently the largest single dish ground-based imaging air Cherenkov telescope in operation. During its first cycle of observations more than 20 extragalactic objects have been observed, and very high energy gamma-ray signals have been detected ...
Errando, M.
core   +2 more sources

Generalized Chemical Model for Warm Dense Hydrogen: Ionization Potential Depression and Molecular Dissociation Shifts

Contributions to Plasma Physics, EarlyView.
ABSTRACT Warm dense matter (WDM) is a complex state, where quantum effects, thermal excitations, and strong interparticle correlations coexist. Understanding its microscopic composition and medium‐induced modifications of atomic and molecular properties is essential for planetary modeling, fusion research, and high‐energy‐density experiments.
L. T. Yerimbetova, Yu. V. Arkhipov, Ye. S. Mukhametkarimov, A. E. Davletov, I. M. Tkachenko   +4 more
wiley   +1 more source

Quenching the Hubbard Model: Comparison of Nonequilibrium Green's Function Methods

Contributions to Plasma Physics, EarlyView.
ABSTRACT We benchmark nonequilibrium Green's function (NEGF) approaches for interaction quenches in the half‐filled Fermi–Hubbard model in one and two dimensions. We compare fully self‐consistent two‐time Kadanoff–Baym equations (KBE), the generalized Kadanoff–Baym ansatz (GKBA), and the recently developed NEGF‐based quantum fluctuations approach (NEGF‐
Jan‐Philip Joost, Christopher Makait, Alexander Osterkorn, Erik Schroedter   +3 more
wiley   +1 more source

Gaussian processes reconstruction of dark energy from observational data

European Physical Journal C: Particles and Fields, 2018
In the present paper, we investigate the dark energy equation of state using the Gaussian processes analysis method, without confining a particular parametrization. The reconstruction is carried out by adopting the background data including supernova and
Ming-Jian Zhang, Hong Li
doaj   +1 more source

Fundamental Physics With Cosmic High-Energy Gamma Rays

, 2016
High-energy photons (above the MeV) are a powerful probe for astrophysics and for fundamental physics under extreme conditions. During the recent years, our knowledge of the high-energy gamma-ray sky has impressively progressed thanks to the advent of ...
De Angelis, Alessandro
core   +1 more source

The Virial Expansion of the Hydrogen Equation of State in Comparison to PIMC Simulations: The Quasiparticle Concept, IPD, and Ionization Degree

Contributions to Plasma Physics, EarlyView.
ABSTRACT The properties of plasmas in the low‐density limit are described by virial expansions. Analytical expressions are known for the lowest virial coefficients from Green's function approaches. Recently, accurate path‐integral Monte Carlo (PIMC) simulations were performed for the hydrogen plasma at low densities by Filinov and Bonitz (Phys. Rev.
Gerd Röpke, Chengliang Lin, W. Ebeling, H. Reinholz   +3 more
wiley   +1 more source

High energy cosmic-rays: puzzles, models, and giga-ton neutrino telescopes

, 2003
The existence of cosmic rays of energies exceeding 10^20 eV is one of the mysteries of high energy astrophysics. The spectrum and the high energy to which it extends rule out almost all suggested source models.
A Achterberg, A M Hillas, Arons, D Band, D Casper, D J Bird, D J Bird, E Boldt, E Waxman, E Waxman, E Waxman, E Waxman, E. Waxman, F Halzen, G L Fogli, G T Zatsepin, J Bednarz, J Bloom, J Hjorth, J N Bahcall, J N Bahcall, J N Bahcall, K Greisen, K Z Stanek, M Drees, M Milgrom, M Nagano, M Schmidt, M Vietri, N Hayashida, N N Efimov, P Bhattacharjee, P Mészáros, R Blandford, T Abu-Zayyad, T J Galama, T Piran, W I Axford, Y Fukuda   +38 more
core   +1 more source

Kinetic Contribution to the Arbitrary Order Odd Frequency Moments of the Dynamic Structure Factor

Contributions to Plasma Physics, EarlyView.
ABSTRACT An exact expression is derived for the kinetic contribution to the odd (arbitrary order) frequency moments of the dynamic structure factor via a finite summation that features averages of even (all lower orders) powers of the momentum over the exact momentum distribution.
Panagiotis Tolias, Tobias Dornheim, Jan Vorberger   +2 more
wiley   +1 more source

Holographic entanglement entropy and complexity for the cosmological braneworld model

Journal of High Energy Physics
In a recent study [1], the time-dependent entanglement entropy of the universe undergoing expansion according to various power laws has been analyzed within the framework of the braneworld model. The results of the entanglement entropy in that paper take
Souvik Paul, Gopinath Guin, Sunandan Gangopadhyay   +2 more
doaj   +1 more source

Reweighting Scheme for the Calculation of Grand‐Canonical Expectation Values in Quantum Monte Carlo Simulations With a Fermion Sign Problem

Contributions to Plasma Physics, EarlyView.
ABSTRACT Ab initio path integral Monte Carlo (PIMC) simulations constitute the gold standard for the estimation of a broad range of equilibrium properties of a host of interacting quantum many‐body systems spanning a broad range of conditions from ultracold atoms to warm dense quantum plasmas.
Paul Hamann, Jan Vorberger, Tobias Dornheim   +2 more
wiley   +1 more source