Tetrahydrothiophene (THT) is an odor additive used widely in the world. This paper introduced a new pre-concentration techniques coupled with a PFPD detector to analyze THT in ambient air samples. The positive results have been obtained in both standard and actual sample analysis. The results indicate that using Summa canisters or Tedlar bags to take the samples and followed by pre concentratio...

A sensitive and simple color sensor for indole vapors has been developed based on the Ehrlich-type reaction in solid polymer film. Upon 60-min exposure of the film sensor to the air containing 5 - 100 ppb of indole vapors, pink or magenta color could be recognized by the naked eyes. Alternatively, a trial gas detector tube has been prepared by mixing the reagents with sea sand. When air (100 mL...

The Pierre Auger Observatory has been collecting data in a stable manner since January 2004. We present here a study of the cosmic ray composition using events recorded in hybrid mode during the first years of data taking. These are air showers observed by the fluorescence detector as well as the surface detector, so the depth of shower maximum, Xmax, is measured directly. The cosmic ray compos...

Calorimetric measurements of extensive air showers are performed with the fluorescence detector of the Pierre Auger Observatory. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory operates several instruments to record atmospheric conditions across and above the detector site. New developments have been made in the study of the aerosol optical ...

The HEGRA experiment is an air shower detector system for the study of neutral and charged cosmic rays in the energy range between 500 GeV to 10 PeV. Here we give an overview of how the HEGRA detector is used to search for TeV γradiation associated with Gamma-Ray Bursts (GRBs) registered with the Burst And Transient Source Experiment (BATSE) on board the Compton Gamma-Ray Observatory. Furthermo...

A 1.4 m3 ice Cherenkov tank was installed at the South Pole during the 2000-2001 austral summer. The penetrating muon rate was measured for three different incident angles with a scintillator muon telescope incorporating the tank as absorber. The freezing process was monitored and the detector was calibrated with the penetrating muons. The calibration is compared to a GEANT simulation of the de...

Simulations of optical image of a shower are implemented into a procedure of shower energy determination. This ”top-down” approach starts with shower development and fluorescence light production in the air, to obtain the expected detector response. In this paper, distributions of energy deposited by a shower in the air through ionization, as obtained from CORSIKA, are used to derive the flux o...

Background: Nanotechnology is a new approach that has been lionized in recent years. One of its applications is its consumption as an absorbent. In this study, the single-wall carbon nanotubes (SWCNTs) were used as an absorbent for sampling benzene in the air. Materials and Methods: For this study, SWCNTs manufactured by Iran and SKC’s activated charcoal were used for sampling benzene vapors....

Recent reports of superhigh energy cosmic rays beyond the expected spectral cuto have intensiied interest in the unknown origin of the highest energy cosmic rays. There is a need for a much larger data base of more precisely measured air showers. This requires new sensitive detectors of enormous aperture. Combining a ground array of particle counters with an optical detector of atmospheric uore...

Data from the IceCube detector in its 22string configuration (IC22) were used to directly measure the atmospheric muon energy spectrum near the horizon. After passage through more than 10 km of ice, muon bundles from air showers are reduced to single muons, whose energy can be estimated from the total number of photons registered in the detector. The energy distribution obtained in this way is ...