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Coefficients α ρ , β ρ , and α P Used to Correct Shower Sizes for Atmospheric Effects on Shower Development, in Bins of sec θ sec θ α ρ (kg −1 m 3 ) β ρ (kg −1 m 3 ) α P (h Pa −1 )

Coefficients α ρ , β ρ , and α P Used to Correct Shower Sizes for Atmospheric Effects on Shower Development, in Bins of sec θ sec θ α ρ (kg −1 m 3 ) β ρ (kg −1 m 3 ) α P (h Pa −1 )

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A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 10(18) eV at the Pierre Auger Observatory is presented. This search is performed as a function of both declination and right ascension in several energy ranges above 10(18) eV, and reported in terms of dipolar and quadrupolar coeff...

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... d denotes here the average daily density at the time the event was recorded. The measured coefficients α ρ , β ρ and α P -given in Table 1-give the influence on the shower sizes of the air density (and thus temperature) at long and short timescales on theMolì ere radius (and hence the lateral profiles of the showers) and of the pressure on the longitudinal development of air showers, respectively. Applying these corrections to the energy assignments of showers allows us to cancel spurious variations of the event rate in right ascension, where typical amplitudes amount to a few per thousand when considering data sets collected over full years. ...

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A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 10(18) eV at the Pierre Auger Observatory is reported. For the first time, these large-scale anisotropy searches are performed as a function of both the right ascension and the declination and expressed in terms of dipole and quadr...

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... The transition between the galactic and extragalctic components is still an open problem of the high energy astrophysics. The Auger data show that the large scale distribution of the cosmic ray arrival directions is compatible with an isotropic flux, in the energy range from ∼ 10 18 eV up to the ankle [3]. This result is incompatible with a galactic origin of the light component that seems to dominate the flux in this energy range [3]. ...
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... The Auger data show that the large scale distribution of the cosmic ray arrival directions is compatible with an isotropic flux, in the energy range from ∼ 10 18 eV up to the ankle [3]. This result is incompatible with a galactic origin of the light component that seems to dominate the flux in this energy range [3]. Therefore, the transition between these two components is expected to take place below 10 18 eV. ...
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The origin of the ultrahigh energy cosmic ray remains being a mystery. However, a considerable progress has been made in the past few years due to the good quality data recorded by current cosmic ray observatories. One of the recent achievements is obtaining firm observational evidence about the extragalactic origin of the most energetic cosmic rays by the Pierre Auger observatory. On the other hand, it is believed that there is a non-null turbulent magnetic field that fills the intergalactic medium. Therefore, the presence of the intergalactic magnetic field can play an important role on the propagation of the ultrahigh energy cosmic rays through the Universe, which in principle can be relevant to interpret the experimental data. In this work we present a system of partial differential equations that describes the propagation of the ultrahigh energy cosmic rays through the Universe, in the presence of a turbulent intergalactic magnetic field, that includes the diffusive and the ballistic regime of propagation and also the transition between them. Also, as an example of application, the system of equations is solved numerically in a simplified physical situation.