The Pierre Auger Observatory, the world-largest cosmic-ray detector, has been measuring ultrahigh-energy cosmic rays in the Southern Hemisphere since 2004. A major upgrade program has begun recently, ...which will enhance the particle-identification sensitivity of the Observatory's surface detector. This upgrade program includes the replacement of the electronics boards of more than 1600 surface detector stations. A test system has been developed by the particle physics group at the University of Siegen, which allows emulating the response of a surface detector station to perform functionality verification tests of the new electronics boards. The test system consists of a single-board Linux-based computer, on which the system control and data analysis software is running, a 6-channel 500 MS/s digital-to-analogue converter card, which is equipped with a Field Programmable Gate Array and an ARM-based processor, that allow generating high-precision arbitrary pulse forms, a microcontroller data acquisition and a programmable power card, which supplies voltages for the test system and the system under test. The test system can be used for versatile applications without additional external equipment. In this paper the hardware, the software and the performance of the test system will be presented.
The Pierre Auger Observatory constitutes the largest detector for measurements of ultra-high-energy cosmic rays (UHECRs) through extended air showers. Radio signals originating from the shower ...development have been detected with suitable antennas in the 50
MHz regime. The Auger engineering radio array (AERA) is being established to exploit the radio technique at these high energies.
The favoured antenna for the first stage of AERA is a logarithmic periodic dipole antenna (LPDA) especially designed to suit the demands of cosmic-ray detection at the Auger site. This antenna is characterized by ultra-broadband sensitivity in the frequency range from 30 to 80
MHz and allows polarization-sensitive measurements of radio signals from all incoming directions. Our characterization of this LPDA includes careful evaluation of the frequency range obtained by combining wire-based dipoles, stability and weather testing, quality assurance in the mass production process, and a benchmark measurement of the sensitivity obtained with the time dependence of the galactic radio background.
For the final setup, a fully calibrated radio-detection system including antennas, filters and low-noise amplifiers is required. We present our approach for this calibration in simulations and measurements.
Cosmic rays at the highest energies Hörandel, Jörg R.
Progress in particle and nuclear physics,
04/2010, Letnik:
64, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Cosmic rays at the highest energies are observed with the Pierre Auger Observatory. Recent results are discussed and the properties of high-energy cosmic rays are reviewed.
In anticipation of the Auger Engineering Radio Array (AERA) to be built at the Pierre Auger Observatory, radio functionality has been built into the Offline analysis framework. For the purpose of ...radio-hybrid analysis and to facilitate a standardized treatment of simulation as well as experimental data it is important that the analysis software for all types of detectors is bundled in one software package. The design philosophy of the Offline package is discussed with particular attention to the recently included radio functionality. In order to illustrate the full potential and flexibility of the software, two example pipelines for analysis of simulations as well as measured data are outlined and discussed.
Radio detection of cosmic ray induced air showers has been demonstrated in dedicated setups in the past. Currently, radio detector setups are being tested at the Pierre Auger Observatory, in ...Malargüe, Argentina, for the detection of ultra high energy cosmic rays.
These efforts have been rewarded with promising results. Radio signals from air showers have been measured in coincidence with the Auger surface detector array.
One of the current data sets consists of 313 triggered radio events in coincidence with the surface detector of the observatory. These events have been used to make first analyses, which focus on the lateral distribution function of the radio signals and on the reconstruction of the arrival direction of cosmic rays. Furthermore, the radio background data have been studied. A periodic variation corresponding to the apparent motion of the galactic center has been observed.
New, stand-alone, radio detectors have been developed and the next phase of testing at the Auger Observatory has started in May 2008. The aim is to show that an independent radio detector at the Auger Observatory with an area of about
20
km
2
is feasible.
Radio detector array simulation Fliescher, Stefan
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
6/2009, Letnik:
604, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Recently radio signals originating from extensive air showers have been observed at the Pierre Auger Observatory. In this note we present software to simulate the response of an array of antenna ...detectors and to reconstruct the radio signals. With this software it is possible to investigate design parameters of an antenna array and to visualize the radio data. We show comparisons between measurements of radio signals from air showers and simulated data which were generated with the REAS2 generator and then processed with the detector simulation and reconstruction software.
We report some radio observations of three fully autonomous and self-triggered antennas installed at the Pierre Auger Observatory, within its Surface Detector (SD). The antennas are the broadband ...active dipoles used in the CODALEMA experiment and led to the detection of events in coincidence with Auger data.
Water Cherenkov Detectors have the nice property of being mostly calorimeters for cosmic ray induced electrons and photons, while providing a clear signal for muons. At large energy deposited in the ...detector, they observe small extended air showers. This makes them interesting detectors to study the background of cosmic ray secondaries. Using low threshold scaler counters, one can follow the flux of cosmic rays on top of the atmosphere, and/or study atmospheric effects on the cosmic ray shower development.
In this paper, background data from the Pierre Auger Observatory are presented. These data are searched for short time-scale variation (one second scale, as expected from Gamma Ray Bursts), and larger time-scale variations, showing modulation effects due to Solar activity (Forbush decreases). Rapid changes in the background flux are also observed during the crossing of storms over the 3000
km
2 of the ground array.
► We introduce the concept of Laternal Trigger Probability functions for EAS. ► We apply this concept to the surface array of the Pierre Auger Observatory. ► Using simulations LTPs are derived for ...energies between 10
17 and 10
19
eV. ► The LTPs can also be obtained from data using hybrid events. ► We show how LTPs from data are in good agreement with simulations.
In this paper we introduce the concept of Lateral Trigger Probability (LTP) function, i.e., the probability for an Extensive Air Shower (EAS) to trigger an individual detector of a ground based array as a function of distance to the shower axis, taking into account energy, mass and direction of the primary cosmic ray. We apply this concept to the surface array of the Pierre Auger Observatory consisting of a 1.5
km spaced grid of about 1600 water Cherenkov stations. Using Monte Carlo simulations of ultra-high energy showers the LTP functions are derived for energies in the range between 10
17 and 10
19
eV and zenith angles up to 65°. A parametrization combining a step function with an exponential is found to reproduce them very well in the considered range of energies and zenith angles. The LTP functions can also be obtained from data using events simultaneously observed by the fluorescence and the surface detector of the Pierre Auger Observatory (hybrid events). We validate the Monte Carlo results showing how LTP functions from data are in good agreement with simulations.
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