1. Studies in the atmospheric monitoring at the Pierre Auger Observatory using the upgraded Central Laser FacilityMarko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Carlos Medina-Hernandez, 2015, published scientific conference contribution Abstract: The Fluorescence Detector (FD) at the Pierre Auger Observatory
measures the intensity of the scattered light from laser tracks
generated by the Central Laser Facility (CLF) and the eXtreme
Laser Facility (XLF) to monitor and estimate the vertical
aerosol optical depth (τ(z,t)). This measurement is needed to
obtain unbiased and reliable FD measurements of the arrival
direction and energy of the primary cosmic ray, and the depth
of the maximum shower development. The CLF was upgraded
substantially in 2013 with the addition of a solid state laser,
new generation GPS, a robotic beam calibration system, better
thermal and dust isolation, and improved software. The upgrade
also included a back-scatter Raman LIDAR to measure τ(z,t).
The new features and applications of the upgraded instrument
are described. These include the laser energy calibration
and the atmospheric monitoring measurements. The first τ(z,t)
results and comparisons after the upgrade are presented using different methods. The first method compares the FD hourly
response to the scattered light from the CLF (or XLF) against
a reference hourly profile measured during a clear night where
zero aerosol contents are assumed. The second method simulates
FD responses with different atmospheric parameters and selects the parameters that provide the best fit to the actual FD
response. A third method uses the new Raman LIDAR receiver
in-situ to measure the back-scatter light from the CLF laser.
The results show a good data agreement for the first and second
methods using FD stations located at the same distance from the
facilities. Preliminary results of τ(z,t) using the Raman LIDAR
are presented as well.
Found in: ključnih besedah
Summary of found: ...The Fluorescence Detector (FD) at the Pierre Auger Observatory
measures...
Keywords: Pierre Auger Observatory, extensive air showers, the Fluorescence Detector, atmospheric monitoring, vertical aerosol optical depth, the Central Laser Facility, the eXtreme Laser Facility
Published: 03.03.2016; Views: 4078; Downloads: 180
 Fulltext (3,96 MB) |
2. Automated procedures for the Fluorescence Detector calibration at the Pierre Auger ObservatoryMarko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Gaetano Salina, 2015, published scientific conference contribution Abstract: The quality of the physics results, derived from the analysis
of the data collected at the Pierre Auger Observatory depends
heavily on the calibration and monitoring of the components of
the detectors. It is crucial to maintain a database containing complete information on the absolute calibration of all
photomultipliers and their time evolution. The low rate of the
physics events implies that the analysis will have to be made
over a long period of operation. This requirement imposes a
very organized and reliable data storage and data management
strategy, in order to guarantee correct data preservation and
high data quality. The Fluorescence Detector (FD) consists of
27 telescopes with about 12,000 phototubes which have to be
calibrated periodically. A special absolute calibration system
is used. It is based on a calibrated light source with a
diffusive screen, uniformly illuminating photomultipliers
of the camera. This absolute calibration is performed every few
years, as its use is not compatible with the operation of the
detector. To monitor the stability and the time behavior,
another light source system operates every night of data
taking. This relative calibration procedure yields more than
2×10[sup]4 raw files each year, about 1 TByte/year. In this
paper we describe a new web-interfaced database architecture
to manage, store, produce and analyse FD calibration data.
It contains the configuration and operating parameters of the
detectors at each instant and other relevant functional
parameters that are needed for the analysis or to monitor
possible instabilities, used for the early discovery of
malfunctioning components. Based on over 10 years of
operation, we present results on the long term performance
of FD and its dependence on environmental variables. We also
report on a check of the absolute calibration values by
analysing the signals left by stars traversing the FD field of
view.
Found in: ključnih besedah
Keywords: Pierre Auger Observatory, Fluorescence Detector, detector calibration and monitoring, automated calibration procedure
Published: 03.03.2016; Views: 3588; Downloads: 198
Fulltext (1,06 MB) |
3. Improvements to aerosol attenuation measurements at the Pierre Auger ObservatoryMax Malacari, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2017, published scientific conference contribution Found in: ključnih besedah
Summary of found: ...aerosol attenuation measurements, Pierre Auger Observatory, fluorescence detector...
Keywords: aerosol attenuation measurements, Pierre Auger Observatory, fluorescence detector
Published: 19.02.2018; Views: 4192; Downloads: 163
Fulltext (1,96 MB) |
4. The energy spectrum of cosmic rays above 1017.2 eV measured by the fluorescence detectors of the Telescope Array experiment in seven yearsJ. P. Lundquist, R.U. Abbasi, 2016, original scientific article Abstract: The Telescope Array (TA) experiment is the largest detector to observe ultra-high-energy cosmic rays in the northern hemisphere. The fluorescence detectors at two stations of TA are newly constructed and have now completed seven years of steady operation. One advantage of monocular analysis of the fluorescence detectors is a lower energy threshold for cosmic rays than that of other techniques like stereoscopic observations or coincidences with the surface detector array, allowing the measurement of an energy spectrum covering three orders of magnitude in energy. Analyzing data collected during those seven years, we report the energy spectrum of cosmic rays covering a broad range of energies above 10^17.2eV measured by the fluorescence detectors and a comparison with previously published results.
Found in: ključnih besedah
Summary of found: ...Telescope Array (TA) experiment is the largest detector to observe ultra-high-energy cosmic rays in the...
Keywords: Cosmic rays, Ultra-high energy, Fluorescence detector, Energy spectrum, Ankle, GZK cutoff
Published: 27.04.2020; Views: 2089; Downloads: 0
Fulltext (1,23 MB) |
5. TA Anisotropy SummaryJ. P. Lundquist, K. Kawata, 2019, published scientific conference contribution Abstract: The Telescope Array (TA) is the largest ultra-high-energy cosmic-ray (UHECR) detector in the northern hemisphere. It consists of an array of 507 surface detectors (SD) covering a total 700 km^2 and three fluorescence detector stations overlooking the SD array. In this proceedings, we summarize recent results on the search for directional anisotropy of UHECRs using the latest dataset collected by the TA SD array. We obtained hints of the anisotropy of the UHECRs in the northern sky from the various analyses.
Found in: ključnih besedah
Summary of found: ...covering a total 700 km^2 and three fluorescence detector stations overlooking the SD array. In...
Keywords: cosmic radiation, UHE detector, fluorescence detector, surface, Telescope Array Experiment, anisotropy, experimental results
Published: 28.04.2020; Views: 2137; Downloads: 72
Fulltext (1,88 MB) |
6. Cosmic Ray Shower Profile Track Finding for Telescope Array Fluorescence DetectorsJ. P. Lundquist, 2016, published scientific conference contribution Abstract: A simple cosmic ray track finding pattern recognition analysis (PRA) method for fluorescence detectors (FD) has been developed which significantly improves Xmax resolution and its dependence on energy. Events which have a clear rise and fall in the FD view contain information on Xmax that can be reliably reconstructed. Shower maximum must be extrapolated for events with Xmax outside the field of view of the detector, which creates a systematic dependence on the fitting function. The PRA method is a model and detector independent approach to removing
these events, by fitting shower profiles to a set of triangles and applying limits on the allowable geometry.
Found in: ključnih besedah
Summary of found: ...pattern recognition analysis (PRA) method for fluorescence detectors (FD) has been developed which significantly improves...
Keywords: UHECR, cosmic rays, fluorescence detector, track finding, pattern recognition
Published: 29.04.2020; Views: 2148; Downloads: 100
Fulltext (1,59 MB) |
