Models of the Knee in the Energy Spectrum of Cosmic Rays
نویسنده
چکیده
The origin of the knee in the energy spectrum of cosmic rays is an outstanding problem in astroparticle physics. Numerous mechanisms have been proposed to explain the structure in the all-particle spectrum. In the article basic ideas of several models are summarized, including diffusive acceleration of cosmic rays in shock fronts, acceleration via cannonballs, leakage from the Galaxy, interactions with background particles in the interstellar medium, as well as new high-energy interactions in the atmosphere. The calculated energy spectra and mean logarithmic masses are compiled and compared to results from direct and indirect measurements.
منابع مشابه
The composition of cosmic rays at the knee ( ∗ )
The solar system is permanently exposed to a vast flux of highly energetic and fully ionized atomic nuclei, the cosmic rays. Their energies extend from the GeV range to at least 10 eV. Over a wide range the energy spectrum follows a power law dN/dE ∝ E . The spectral index changes around 4 PeV from γ ≈ −2.7 to γ ≈ −3.1. This transition phenomenon has been reported for the first time in 1958 [1]...
متن کاملA study on the lateral distribution of Cherenkov light in extensive air showers
The dependence of the lateral distribution of Cherenkov light in simulated extensive air showers to the energy and the mass of the primary cosmic rays has been studied. It has been shown that a previous claim about mass independent proportionality of shower energy to the total Cherenkov photon number is not valid in energies below EEAS ~ 1014 eV. We have found that the core distance of the so c...
متن کاملEnergy spectrum and elemental composition of cosmic rays in the PeV region Recent results and future prospects of the KASCADE experiment
KASCADE (KArlsruhe Shower Core and Array DEtector) is determining flux spectra for different primary mass groups to disentangle the knee feature of the primary cosmic-ray energy spectrum. The energy spectra of the light element groups result in a knee-like bending and a steepening above the knee. The topology of the individual knee positions suggests a rigidity dependence. To proof the rigidity...
متن کاملMeasuring the Cosmic Ray Composition at the Knee with BLANCA
BLANCA is a new, large non-imaging Cerenkov detector located at the CASA-MIA experiment it Dugway, Utah. Using 144 individual Cerenkov detectors, BLANCA covers an area of approximately 0.2 km and has an energy threshold of 300 TeV. The lateral density function (LDF) of the Cerenkov light in air showers is measured. Since the LDF depends on the primary particle species, a change in composition a...
متن کاملMeasuring extensive air showers with Cherenkov light detectors of the Yakutsk array: The energy spectrum of cosmic rays
The energy spectrum of cosmic rays in the range E ∼ 1015 eV to 6 × 1019 eV has been studied using the air Cherenkov light detectors of the Yakutsk array. The total flux of photons produced by relativistic electrons (including positrons as well, hereafter) of extensive air showers in the atmosphere is used as the energy estimator of the primary particle initiating a shower. The resultant differe...
متن کامل