Entropy considerations in constraining the mSUGRA parameter space

We explore the use of two criteria to constraint the allowed parameter space in mSUGRA models. Both criteria are based in the calculation of the present density of neutralinos as dark matter in the Universe. The first one is the usual ``abundance'' criterion which is used to calculate the relic density after the ``freeze-out'' era. To compute the relic density we used the numerical public code micrOMEGAs. The second criterion applies the microcanonical definition of entropy to a weakly interacting and self-gravitating gas evaluating then the change in the entropy per particle of this gas between the ``freeze-out'' era and present day virialized structures. An ``entropy-consistency'' criterion emerges by comparing theoretical and empirical estimates of this entropy. The main objective of our work is to determine for which regions of the parameter space in the mSUGRA model are both criteria consistent with the 2$\sigma$ bounds according to WMAP for the relic density: $0.0945<\Omega_{CDM}h^2<0.1287$. As a first result, we found that for $A_0=0$, sgn$\mu=+$, small values of tan$\beta$ are not favored; only for tan$\beta\simeq50$ are both criteria significantly consistent.Comment: 5 pages, 1 figure. To appear in the Proceedings of X Mexican Workshop on Particles and Fields, Morelia Michoac\'an, M\'exico, November 7-12, 200

Axial Couplings on the World-Line

We construct a world-line representation for the fermionic one-loop effective action with axial and also vector, scalar, and pseudo-scalar couplings. We use this expression to compute a few selected scattering amplitudes. These allow us to verify that our method yields the same results as standard field theory. In particular, we are able to reproduce the chiral anomaly. Our starting point is the second-order formulation for the Dirac fermion. We translate the second order expressions into a world-line action.Comment: 12 pages, LaTeX 2e with array and epsf packages, Postscript figures. Submitted to Phys. Lett. B. Minor corrections, fixed a number of typo

Yukawa Couplings for the Spinning Particle and the World Line Formalism

We construct the world-line action for a Dirac particle coupled to a classical scalar or pseudo-scalar background field. This action can be used to compute loop diagrams and the effective action in the Yukawa model using the world-line path-integral formalism for spinning particles.Comment: 10 pages Latex, two uuencoded postscript figures. Note added at the en

Neutrino production through hadronic cascades in AGN accretion disks

We consider the production of neutrinos in active galactic nuclei (AGN) through hadronic cascades. The initial, high energy nucleons are accelerated in a source above the accretion disk around the central black hole. From the source, the particles diffuse back to the disk and initiate hadronic cascades. The observable output from the cascade are electromagnetic radiation and neutrinos. We use the observed diffuse background X-ray luminosity, which presumably results {}from this process, to predict the diffuse neutrino flux close to existing limits from the Frejus experiment. The resulting neutrino spectrum is $E^{-2}$ down to the \GeV region. We discuss modifications of this scenario which reduce the predicted neutrino flux.Comment: 12 Pages, LaTeX, TK 92 0

Parallel processing of radio signals and detector arrays in CORSIKA 8

This contribution describes some recent advances in the parallelization of the generation and processing of radio signals emitted by particle showers in CORSIKA 8. CORSIKA 8 is a Monte Carlo simulation framework for modeling ultra-high energy particle cascades in astroparticle physics. The aspects associated with the generation and processing of radio signals in antennas arrays are reviewed, focusing on the key design opportunities and constraints for deployment of multiple threads on such calculations. The audience is also introduced to Gyges, a lightweight, header-only and flexible multithread self-adaptive scheduler written compliant with C++17 and C++20, which is used to distribute and manage the worker computer threads during the parallel calculations. Finally, performance and scalability measurements are provided and the integration into CORSIKA 8 is commented

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO