Search results for "COSMIC"
showing 10 items of 656 documents
Impact of general reionization scenarios on extraction of inflationary parameters
2010
Determination of whether the Harrison-Zel'dovich spectrum for primordial scalar perturbations is consistent with observations is sensitive to assumptions about the reionization scenario. In light of this result, we revisit constraints on inflationary models using more general reionization scenarios. While the bounds on the tensor-to-scalar ratio are largely unmodified, when different reionization schemes are addressed, hybrid models are back into the inflationary game. In the general reionization picture, we reconstruct both the shape and amplitude of the inflaton potential. We discuss how relaxing the simple reionization restriction affects the reconstruction of the potential through the c…
Primordial power spectrum features in phenomenological descriptions of inflation
2016
We extend an alternative, phenomenological approach to inflation by means of an equation of state and a sound speed, both of them functions of the number of $e$-folds and four phenomenological parameters. This approach captures a number of possible inflationary models, including those with non-canonical kinetic terms or scale-dependent non-gaussianities. We perform Markov Chain Monte Carlo analyses using the latest cosmological publicly available measurements, which include Cosmic Microwave Background (CMB) data from the Planck satellite. Within this parametrization, we discard scale invariance with a significance of about $10\sigma$, and the running of the spectral index is constrained as …
Searches for small-scale anisotropies from neutrino point sources with three years of IceCube data
2015
Recently, IceCube found evidence for a diffuse signal of astrophysical neutrinos in an energy range of $60\,\mathrm{TeV}$ to the $\mathrm{PeV}$-scale. The origin of those events, being a key to understanding the origin of cosmic rays, is still an unsolved question. So far, analyses have not succeeded to resolve the diffuse signal into point-like sources. Searches including a maximum-likelihood-ratio test, based on the reconstructed directions and energies of the detected down- and up-going neutrino candidates, were also performed on IceCube data leading to the exclusion of bright point sources. In this paper, we present two methods to search for faint neutrino point sources in three years o…
Cosmopolitanism and Human Reason
2019
Over and above the modalities with which it is expressed in the domains of Kant’s system, the theme of cosmopolitanism embodies the meaning of a philosophy seen as a plan to build on the connection between man, polis and reason; an essential connection that in human reason identifies not a simple endowment which everyone has by nature but a form of life to be realized in the world, a purpose whose binding strength is only fully expressed in the public dimension.
Filosofia in senso cosmico e destinazione dell'uomo
2020
Conceived by Kant as a spontaneous self-legislating activity, reason produces drives, norms and desires in which man, as a rational being, is a participant, but over which, as a finite being, he can neither fully exercise his cognitive power nor exercise his will to the very end. The expression “human reason” thus describes the condition in which we never find ourselves at home; or, rather, we live in our own house as guests who are not always at ease. That is to say, reason puts us in an embarrassing situation (Verlegenheit), because it reminds us that the space in which we think we can move so easily, and in which we trust we are well acclimatized in virtue of our knowledge and our skills…
Kernel estimation and display of a five-dimensional conditional intensity function
2018
The aim of this paper is to find a convenient and effective method of displaying some second order properties in a neighbourhood of a selected point of the process. The used techniques are based on very general high-dimensional nonparametric smoothing developed to define a more gen- eral version of the conditional intensity function introduced in earlier earthquake studies by Vere-Jones (1978). 1976) is commonly used for such a purpose in discussing the cumulative behavior of interpoint distances about an initial point. It is defined as the expected number of events falling within a given distance of the initial event, divided by the overall density (rate in 2-dimensions) of the process, sa…
Cosmic ray composition and energy spectrum from 1–30 PeV using the 40-string configuration of IceTop and IceCube
2012
Astroparticle physics 42, 15 - 32 (2013). doi:10.1016/j.astropartphys.2012.11.003
Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger Observatory
2011
We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 × 1017 eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.
The Byzantine Scholia to Aristotle and Empedocles’ Cosmic Cycle
2020
Abstract Some Byzantine scholia to Aristotle offer numerical indications on the time-length of some phases of Empedocles’ cosmic cycle. In recent years an interpretation has become established, according to which the scholia pro-vide evidence for a cycle with three periods: the Sphairos and two opposite phases of Love’s and Strife’s unfolding. This paper emphasizes, in contrast, that the picture of the cycle we can draw from the scholia is not as clear-cut as generally supposed. On the contrary, the scholia can be adapted to dif-ferent, even contrasting, reconstructions of the Empedoclean cycle. Moreo-ver, they seem to challenge the received idea of Empedocles’ cycle as the Sphairos and two…
A New Low Background Laboratory in the Pyhäsalmi Mine : Towards 14C free liquid scintillator for low energy neutrino experiments
2017
A new low background laboratory in Pyhäsalmi mine in the Central Finland has been put into operation in the beginning of 2017. The laboratory operates at the depth of 1436 m (~4100 meters of water equivalent). In this paper, we present description of the laboratory’s existing facility and background conditions. In the laboratory, a series of measurements has been started where the 14C concentration is determined from several liquid scintillator samples. A dedicated setup has been designed and constructed with the aim of measuring the 14C/12C ratio smaller than 10-18 . peerReviewed