摘要:

In this laboratory we will see some to those characteristics of silicon detectors which make them very useful in the fields of Medical Physics. One of the application of these devices that we will work with is in detecting low energy X‐ray radiation (from 6 to 30KeV). In this laboratory we will learn something of the aquisition system (LabVIEW), the readout system (PCI‐1200 card, buffer, RX64 chip and the silicon detector on the printed circuit board) and the measurements of the X rays (coming from a radiation source) for different positions of the detector, in searching for improving the efficiency of detection. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604091

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

The Pierre Auger Observatory, now under construction in Argentina, will be an important tool in the solution of the puzzle of the ultra high energy cosmic rays. It will cover a total area of 6000 km2with 3200 surface Cherenkov detectors and 8 fluorescence detectors. The Pierre Auger Observatory is the result of an international effort. It has been designed to study cosmic rays with energies ⩾ 1018eV with high statistics, achieving its full efficiency at energies ⩾ 1019.5eV. The operation of a prototype detector in Argentina, deployed during the first stage of the construction in the southern site, has demonstrated the capability of the Pierre Auger Observatory to accomplish the objectives for which it was designed. The goal, the design and the status of the Pierre Auger observatory are briefly described in this paper. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604092

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

We present preliminary measurements of the thermoluminescent response of LiF:Mg,Ti irradiated with low‐fluences of low energy light ions. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604093

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

In recent experiments, we have for the first time measured near‐barrier and sub‐barrier transfer and/or breakup yields for an exotic Borromean nucleus6He, on a209Bi target. An isolated4He group was observed at an effectiveQ‐value of approximately −2.5 MeV whose integrated cross section was exceptionally large, greatly exceeding the fusion yield both above and below the barrier. Simultaneously measured elastic‐scattering angular distributions required total reaction cross sections that confirmed this large yield. Preliminary coupled‐channels calculations suggested that the reaction mechanism can best be described by direct breakup and neutron transfer to unbound states in211Bi. The calculations also predicted an enhancement in the sub‐barrier fusion yield due to coupling to the transfer and/or breakup channel, which strongly suggested that this is the doorway state that accounts for the remarkable suppression of the fusion barrier that was observed in a previous experiment. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604094

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

The ATLAS (A Toroidal LHC ApparatuS) detector for the Large Hadron Collider at CERN, which is under construction, will study the products of proton‐proton collisions at energies of up to 14 TeV. The outermost part of the ATLAS detector, the Muon Spectrometer, is designed to identify muons with high efficiency, and measure their momenta with a resolution of ∼10&percent; at pT=1 TeV/c. The measurement is performed inside the toroidal field created by powerful air‐core toroid magnets with the help of the ATLAS Muon precision tracking system. Three Greek universities have taken the responsibility to construct 30,000 drift tubes of ∼1.7 m length, to test them and finally assemble them into 120 BIS (Barrel Inner Small) chambers. The design of the muon drift tubes aims at high detection efficiency (>95&percent;) and a spatial single tube resolution of <80 &mgr;m. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604095

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

In this work we present the electronics developed into a complete data acquisition system (DAS) for a water Cherenkov detector (WCD) in order to detect cosmic rays with energies from 1 × 1014to 1 × 1016eV. The components are: a high voltage source, a bleeder circuit for each photomultiplier, an electronic unit to amplify, compare, determine coincidence and sum the signals produced by the PMTs, a control circuit to digitalize and store the information corresponding to a valid event and finally an interface to a PC to record data for further analysis. The sampling rate of the system is 40 MHz. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604096

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

In this work we present a progress report of the project of a high energy cosmic ray observatory located at Pico de Orizaba mountain. One of the goals of this facility will be to contribute to the understanding of the origin of the cosmic rays at energies around the feature known as the knee. To achieve this goal we plan to use a hybrid detector composed of a surface detector array and a fluorescence telescope. The design and expected performance of the fluorescent detector is presented. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604097

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

The KTeV experiment at Fermilab gives a good opportunity to investigate the neutral cascade semi‐leptonic decays. The study of the &Ygr;0muon semi‐leptonic decay, &Ygr;0→ &Sgr;+&mgr;−&ngr;¯&mgr;has a theoretical motivation to understand the interplay of strong (QCD) and electro‐weak interactions. However this decay is suppressed by phase space with only 21 MeV of energy release, making it difficult to collect a large sample of decays. In the present analysis we briefly discuss the theory of the decay, the experimental apparatus of KTeV and the reconstruction steps of the &Ygr;0→ &Sgr;+&mgr;−&ngr;¯&mgr;decay. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604098

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

The suggested existence of temporal structure in the signals of extensive air showers (EAS) for energies greater than 1017eV at core distances of about 500 m, and its correlation with important parameters of EASs has stimulated us to study this structure for showers with lower energies in an Auger water Cherenkov detector(WCD). Preliminary analysis of experimental data on the widths of signals in a WCD and their correlation with other parameters of the signal are presented. The detector was triggered by the EAS‐BUAP array which operates in the region of 1014– 1016eV. The distance of the WCD to the EAS core is larger than 30 m. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604099

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

We describe the operation and performance of the first stage of the EAS‐UAP extensive air shower array, as a detector of very high energy cosmic rays (Eo> 1014eV) after one year of operation. The array is located at the Campus of Puebla University, 2200 m above sea level. It consists of 10 liquid scintillator detectors, each with an active surface of 1m2and a detector spacing of 20 m in a square grid. One Auger Water Cherenkov detector is also included as part of the array. In this report we discuss the stability, the calibration and lateral distribution function reconstruction capabilities of the detector array. We also present the analysis of the shower size spectrum. In addition, the main characteristics of this array allow us to use it as an educational and training facility. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1604100

出版商:AIP    

年代:1903

数据来源: AIP