82 research outputs found
Enhancing the cosmic-ray mass sensitivity of air-shower arrays by combining radio and muon detectors
The muonic and electromagnetic components of air showers are sensitive to the
mass of the primary cosmic particle. The sizes of the components can be
measured with particle detectors on ground, and the electromagnetic component
in addition indirectly via its radio emission in the atmosphere. The
electromagnetic particles do not reach the ground for very inclined showers. On
the contrary, the atmosphere is transparent for the radio emission and its
footprint on ground increases with the zenith angle. Therefore, the radio
technique offers a reliable detection over the full range of zenith angles, and
in particular for inclined showers. In this work, the mass sensitivity of a
combination of the radio emission with the muons is investigated in a case
study for the site of the Pierre Auger Observatory using CORSIKA Monte Carlo
simulations of showers in the EeV energy range. It is shown, that the
radio-muon combination features superior mass separation power in particular
for inclined showers, when compared to established mass observables such as a
combination of muons and electrons or the shower maximum Xmax. Accurate
measurements of the energy-dependent mass composition of ultra-high energy
cosmic rays are essential to understand their still unknown origin. Thus, the
combination of muon and radio detectors can enhance the scientific performance
of future air-shower arrays and offers a promising upgrade option for existing
arrays
Combined Detection of Muons and Radio Emission of Cosmic-Ray Air Showers
In this thesis, a novel technique is developed to estimate the cosmic-ray mass on a per-event level by combining radio and muon measurements of air showers. The new technique is studied using Monte Carlo simulations of air showers and then verified experimentally based on data from the Muon Detector of AMIGA and the Radio Detector AERA of the Pierre Auger Observatory in Argentina
Enhancing the cosmic-ray mass sensitivity of air-shower arrays by combining radio and muon detectors
The muonic and electromagnetic components of air showers are sensitive to the mass of the primary cosmic particle. The sizes of the components can be measured with particle detectors on ground, and the electromagnetic component in addition indirectly via its radio emission in the atmosphere. The electromagnetic particles do not reach the ground for very inclined showers. On the contrary, the atmosphere is transparent for the radio emission and its footprint on ground increases with the zenith angle. Therefore, the radio technique offers a reliable detection over the full range of zenith angles, and in particular for inclined showers. In this work, the mass sensitivity of a combination of the radio emission with the muons is investigated in a case study for the site of the Pierre Auger Observatory using CORSIKA Monte Carlo simulations of showers in the EeV energy range. It is shown, that the radio-muon combination features superior mass separation power in particular for inclined showers, when compared to established mass observables such as a combination of muons and electrons or the shower maximum X max
Xmax. Accurate measurements of the energy-dependent mass composition of ultra-high energy cosmic rays are essential to understand their still unknown origin. Thus, the combination of muon and radio detectors can enhance the scientific performance of future air-shower arrays and offers a promising upgrade option for existing arrays
Nel positively regulates the genesis of retinal ganglion cells by promoting their differentiation and survival during development
Peer reviewedPublisher PD
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than 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
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
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