Feasibility study of the water Cherenkov detector as a D-T fusion power monitor in the system using neutron activation of flowing water. First experimental phase

International Nuclear Information System (INIS)

Verzilov, Yury M.; Ochiai, Kentaro; Nishitani, Takeo

2003-09-01

The technique of monitoring D-T neutrons using water flow is based on the reaction of the 16 O(n, p) 16 N. In order to significantly improve the D-T neutron monitoring system in the ITER reactor in comparison with the system that uses a γ-ray scintillation detector, a new approach was proposed. The basic idea of this approach is to utilize the Cherenkov light, produced by energetic β-particles from 16 N in water near the first wall of the fusion reactor, and then deliver the light by the optical fiber to the remote light detector. The proof of the principle experiment is divided into two phases. The main idea of the first experimental phase is to examine Cherenkov light measurements using a remotely located water and light detector. During the second phase the water radiator will be placed next to the neutron source, then the Cherenkov light will be transferred by an optical fiber to the remotely located light detector. For the purpose of the first experimental phase, a water Cherenkov detector was installed in the shielded measurement room. A closed water loop, with circulating water, was used to transport 16 N from the D-T source to the Cherenkov detector. The experiment was carried out at FNS/JAERI, with the accelerator set to a direct current mode, the source neutron yield around 2 x 10 11 n/s, and the water flowage approximately 2 m/s. The registered Cherenkov signal was identified as the light produced by β-particles from 16 N using the time decay and the energy spectra data. According to the present study, the water Cherenkov detector is very effective for measurements of the 16 N activity, due to high counting efficiency, absence of the scintillation detector and simplicity of the method. (author)

Age of underground waters: isotopes contribution

International Nuclear Information System (INIS)

Chery, L.; Olive, Ph.

2006-01-01

Does water has an age? The age of underground waters can be the duration of their underground travel between their infiltration inside the ground and their captation at a spring or a drilled well. The isotopic geochemistry comes to the support of classical geochemistry to estimate these residence times. Radio-isotopes, like tritium for young waters or carbon 14 for old waters, are used as chronometers to interpret the recharge ways, the flow mechanisms and the residence times of underground waters. Their use is presented in this article with some theoretical recalls and some examples of application. (J.S.)

Study on single-channel signals of water Cherenkov detector array for the LHAASO project

Energy Technology Data Exchange (ETDEWEB)

Li, H.C., E-mail: lihuicai@ihep.ac.cn [University of Nankai, Tianjin 300071 (China); Yao, Z.G.; Chen, M.J. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Yu, C.X. [University of Nankai, Tianjin 300071 (China); Zha, M.; Wu, H.R.; Gao, B.; Wang, X.J. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Liu, J.Y.; Liao, W.Y. [University of Nankai, Tianjin 300071 (China); Huang, D.Z. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

2017-05-11

The Large High Altitude Air Shower Observatory (LHAASO) is planned to be built at Daocheng, Sichuan Province, China. The water Cherenkov detector array (WCDA), with an area of 78,000 m{sup 2} and capacity of 350,000 tons of purified water, is one of the major components of the LHAASO project. A 9-cell detector prototype array has been built at the Yangbajing site, Tibet, China to comprehensively understand the water Cherenkov technique and investigate the engineering issues of WCDA. In this paper, the rate and charge distribution of single-channel signals are evaluated using a full detail Monte Carlo simulation. The results are discussed and compared with the results obtained with prototype array.

High-Energy Astrophysics with the High Altitude Water Cherenkov (HAWC) Observatory

Science.gov (United States)

Pretz, John; HAWC Collaboration

2013-04-01

The High Altitude Water Cherenkov (HAWC) observatory, under construction at Sierra Negra in the state of Puebla, Mexico, consists of a 22500 square meter area of water Cherenkov detectors: water tanks instrumented with light-sensitive photomultiplier tubes. The experiment is used to detect energetic secondary particles reaching the ground when a 50 GeV to 100 TeV cosmic ray or gamma ray interacts in the atmosphere above the experiment. By timing the arrival of particles on the ground, the direction of the original primary particle may be resolved with an error of between 1.0 (50 GeV) and 0.1 (10 TeV) degrees. Gamma-ray primaries may be distinguished from cosmic ray background by identifying the penetrating particles characteristic of a hadronic particle shower. The instrument is 10% complete and is performing as expected, with 30% of the channels anticipated by the summer of 2013. HAWC will complement existing Imaging Atmospheric Cherenkov Telescopes and space-based gamma-ray telescopes with its extreme high-energy sensitivity and its large field-of-view. The observatory will be used to study particle acceleration in Pulsar Wind Nebulae, Supernova Remnants, Active Galactic Nuclei and Gamma-ray Bursts. Additionally, the instrument can be used to probe dark matter annihilation in halo and sub-halos of the galaxy. We will present the sensitivity of the HAWC instrument in the context of the main science objectives. We will also present the status of the deployment including first data from the instrument and prospects for the future.

Cherenkov radiation

International Nuclear Information System (INIS)

Hubert, P.

1955-01-01

When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

Organ nic pollutants in underground water

International Nuclear Information System (INIS)

Hussein, H. H.

1998-01-01

Many organic compounds have been diagnosed in underground and surface waters, and there are many theories that explain the source of the dangerous materials on Punic health. The source of pollution could be the underground stored fuel or the polluted water in farms saturated with agricultural insecticides and chemical fertilizers, or there could be leaks in sewage water wastes. The source of pollution could also be the water surfaces in the areas of garbage disposal or industrial and home waste discharge. Due to the fact that the underground water is separated from oxygen in the air, its ability on self-purification is very low, in that the micro-organism that will do the dismantling and decomposition of the organic materials that pollute the water are in need for oxygen. In the event that underground water is subject to pollution m there are many methods for t resting the polluted water including the chemical decomposition method by injecting the polluted areas with neutralizing or oxidizing chemicals, such as Ozone, Chlorine or Hydrogen Peroxide. The mechanical methods could be used for getting rid of the volatile organic materials. As to biological decomposition, it is done with the use of bacteria in dismantling the poisonous materials into un poisonous materials. The preliminary analysis of water samples in one of the water wells in Sar ir and Tazarbo in Great Jamahirieh indicated that the concentration of total organic compounds (TOC) exceeded the internationally allowed limits. This indicates a deterioration of quality of some of underground water resources. It is well known that some of the organic pollutants have a great role in causing dangerous diseases, such as the polynuclear aromatic hydrocarbons and some halogenated compounds that cause cancer. Therefore, much research is required in this field for diagnosing the polluting organic compounds and determining the suitability of this water for drinking or for human consumption. (author). 21 refs., 6 figs

On Cherenkov light production by irradiated nuclear fuel rods

International Nuclear Information System (INIS)

Branger, E.; Grape, S.; Svärd, S. Jacobsson; Jansson, P.; Sundén, E. Andersson

2017-01-01

Safeguards verification of irradiated nuclear fuel assemblies in wet storage is frequently done by measuring the Cherenkov light in the surrounding water produced due to radioactive decays of fission products in the fuel. This paper accounts for the physical processes behind the Cherenkov light production caused by a single fuel rod in wet storage, and simulations are presented that investigate to what extent various properties of the rod affect the Cherenkov light production. The results show that the fuel properties have a noticeable effect on the Cherenkov light production, and thus that the prediction models for Cherenkov light production which are used in the safeguards verifications could potentially be improved by considering these properties. It is concluded that the dominating source of the Cherenkov light is gamma-ray interactions with electrons in the surrounding water. Electrons created from beta decay may also exit the fuel and produce Cherenkov light, and e.g. Y-90 was identified as a possible contributor to significant levels of the measurable Cherenkov light in long-cooled fuel. The results also show that the cylindrical, elongated fuel rod geometry results in a non-isotropic Cherenkov light production, and the light component parallel to the rod's axis exhibits a dependence on gamma-ray energy that differs from the total intensity, which is of importance since the typical safeguards measurement situation observes the vertical light component. It is also concluded that the radial distributions of the radiation sources in a fuel rod will affect the Cherenkov light production.

The performance of a prototype array of water Cherenkov detectors for the LHAASO project

Science.gov (United States)

An, Q.; Bai, Y. X.; Bi, X. J.; Cao, Z.; Chang, J. F.; Chen, G.; Chen, M. J.; Chen, S. M.; Chen, S. Z.; Chen, T. L.; Chen, X.; Chen, Y. T.; Cui, S. W.; Dai, B. Z.; Du, Q.; Danzengluobu; Feng, C. F.; Feng, S. H.; Gao, B.; Gao, S. Q.; Ge, M. M.; Gu, M. H.; Hao, X. J.; He, H. H.; Hou, C.; Hu, H. B.; Hu, X. B.; Huang, J.; Huang, W. P.; Jia, H. Y.; Jiang, K.; Liu, J.; Liu, J. L.; Liu, J. S.; Liu, S. B.; Liu, Y.; Liu, Y. N.; Li, Q. J.; Li, C.; Li, F.; Li, H. C.; Li, X. R.; Lu, H.; Lv, H. K.; Mao, Y. J.; Ma, L. L.; Ma, X. H.; Shao, J.; Shao, M.; Sheng, X. D.; Sun, G. X.; Sun, Z. B.; Tang, Z. B.; Wu, C. Y.; Wu, H. R.; Wu, Q.; Xiao, G.; Xu, Y.; Yang, Q. Y.; Yang, R.; Yao, Z. G.; You, X. H.; Yuan, A. F.; Zhang, B. K.; Zhang, H. M.; Zhang, S. R.; Zhang, S. S.; Zhang, X. Y.; Zhang, Y.; Zhang, L.; Zhai, L. M.; Zhao, J.; Zhao, L.; Zhao, Z. G.; Zha, M.; Zhou, B.; Zhu, F. R.; Zhu, K. J.; Zhuang, J.; Zuo, X.

2013-10-01

A large high-altitude air-shower observatory (LHAASO) is to be built at Shangri-La, Yunnan Province, China. This observatory is intended to conduct sub-TeV gamma astronomy, and as an important component of the LHAASO project, a water Cherenkov detector array (WCDA) is proposed. To investigate engineering issues and fully understand the water Cherenkov technique for detecting air showers, a prototype array at 1% scale of the LHAASO-WCDA has been built at Yang-Ba-Jing, Tibet, China. This paper introduces the prototype array setup and studies its performance by counting rate of each photomultiplier tube (PMT), trigger rates at different PMT multiplicities, and responses to air showers. Finally, the reconstructed shower directions and angular resolutions of the detected showers for the prototype array are given.

Using underground mine Karst water to solve water supply problem in underground mine

Energy Technology Data Exchange (ETDEWEB)

Wang, W. [Wanbei Mining Administration (China). Liuqiao No. 2 Mine

1995-05-01

There is a very rich karst water resource under the Liuqiao No. 2 underground mine. Under normal mining conditions the drainage is 546 m{sup 3}/h while the maximum drainage is up to 819 m{sup 3}/h. If water inrush occurred from a broken zone of a fault or a sinkhole of the karst, the flow could be up to 3269 m{sup 3}/h. The karst water is of good quality and high in pressure. The water head pressure at -400 m level is about 3.5 MPa. To save mine construction cost, it was decided that the water supply for coal production equipment, mining operation and mine fire control was to be changed from the surface to the underground by drilling a water well to tap the karst water resource. A water well with a depth of 63.3 m was drilled in the -400 m transportation roadway. The diameter of the well is 127 mm and it has a casing pipe with a diameter of 108 mm which is connected to the water supply pipeline. The pressure of the water supply is measured at 23.5 MPa and the water flow rate is 252 m{sup 3}/h. The establishment of the water supply system has achieved great cost saving for Liuqiao No. 2 Mine. 2 figs.

WASTAGE OF UNDERGROUND WATER - STEPS TOWARDS A TRAP?

Directory of Open Access Journals (Sweden)

Shibabrata Pattanayak

2015-06-01

Full Text Available Underground water is used indiscriminately for the purposes like agriculture, serving purposes of urban people, cold drink and mineral water manufacturing etc. As a matter of policy, the rural areas are supplied with underground water in India without considering the factors like actual requirement of water in a particular area, season of scarcity of water etc. It is very common to see the ever open taps of water supplying lines in rural India thronging water continuously and nobody is there to use it. The discharge rate of underground water is far more than the charging rate. This may lead to a very serious condition of water scarcity in near future. Various steps like holding of rain water in the water bodies, selection of crop with requirement of lesser amount of water during the dry months as well as use of Forward Osmosis (FO technology for Cold drinks or Bottled Drinking Water manufacturing from the sea water are advocated.

Water underground

Science.gov (United States)

de Graaf, Inge

2015-04-01

The world's largest assessable source of freshwater is hidden underground, but we do not know what is happening to it yet. In many places of the world groundwater is abstracted at unsustainable rates: more water is used than being recharged, leading to decreasing river discharges and declining groundwater levels. It is predicted that for many regions of the world unsustainable water use will increase, due to increasing human water use under changing climate. It would not be long before shortage causes widespread droughts and the first water war begins. Improving our knowledge about our hidden water is the first step to stop this. The world largest aquifers are mapped, but these maps do not mention how much water they contain or how fast water levels decline. If we can add a third dimension to the aquifer maps, so a thickness, and add geohydrological information we can estimate how much water is stored. Also data on groundwater age and how fast it is refilled is needed to predict the impact of human water use and climate change on the groundwater resource.

Water resistant rhodium plated reflectors for use in the DIRC BaBar Cherenkov detector

CERN Document Server

Benkebil, M; Plaszczynski, S; Schune, M H; Wormser, G

2000-01-01

Early simulation studies showed that reflectors mounted on the photomultipliers would be useful for the DIRC BaBar Cherenkov detector, showing a gain between 20% and 30% in the number of Cherenkov photons. The proof of principle for these reflectors has been obtained during the beam test of a large-scale prototype of the DIRC detector. An extensive R and D has been conducted in order to test different metallization procedures. Indeed, the challenge was to find a metallization technique which can resist the pure de-ionized water (>15 M OMEGA) up to 10 yr. The chosen technology was rhodium plated reflectors. During the first BaBar cosmic run, the measured performance confirmed the results of the simulation, the prototype-II and the R and D.

Visual sensations during megavoltage radiotherapy to the orbit attributable to Cherenkov radiation

International Nuclear Information System (INIS)

Newman, Francis; Asadi-Zeydabadi, Masoud; Durairaj, Vikram D.; Ding Meisong; Stuhr, Kelly; Kavanagh, Brian

2008-01-01

During megavoltage photon and electron beam radiotherapy treatment involving the eye, patients commonly report visual sensations; 'nerve stimulation' is the conventional explanation. We propose that the phenomenon can be attributed to Cherenkov radiation inside the eye. The threshold electron energy for Cherenkov radiation in water is 260 keV. The human retina is able to perceive approximately 5-14 visible photons in 0.001 s. A single 500 keV electron traversing 1 mm of water will induce nearly 15 Cherenkov visible range photons. We propose that a portal image involving the eye will produce sufficient Cherenkov radiation to be detected by the retina

Solution of tasks concerning protection of underground waters and environment

International Nuclear Information System (INIS)

Dubinchuk, V.T.; Polyakov, V.A.

1988-01-01

Use of environment isotopes and indicators in solving problems concerning protection of underground waters and environment is discussed. The applied methods permit to study dynamics of underground waters and to estimate risk of their contamination; to follow the surface and underground waters interrelations using data on infiltration recharge estimation etc. Complex nuclear-geophysical and isotope studies may be applied to detect hindered water exchange zones where liquid industrial waste disposals could be placed with minimum damage to environment. 48 refs.; 74 figs.; 22 tabs

A Cherenkov viewing device for used-fuel verification

International Nuclear Information System (INIS)

Attas, E.M.; Chen, J.D.; Young, G.J.

1990-01-01

A Cherenkov viewing device (CVD) has been developed to help verify declared inventories of used nuclear fuel stored in water bays. The device detects and amplifies the faint ultraviolet Cherenkov glow from the water surrounding the fuel, producing a real-time visible image on a phosphor screen. Quartz optics, a UV-pass filter and a microchannel-plate image-intensifier tube serve to form the image, which can be photographed or viewed directly through an eyepiece. Normal fuel bay lighting does not interfere with the Cherenkov light image. The CVD has been successfully used to detect anomalous PWR, BWR and CANDU (CANada Deuterium Uranium: registered trademark) fuel assemblies in the presence of normal-burnup assemblies stored in used-fuel bays. The latest version of the CVD, known as Mark IV, is being used by inspectors from the International Atomic Energy agency for verification of light-water power-reactor fuel. Its design and operation are described, together with plans for further enhancements of the instrumentation. (orig.)

Cherenkov radiation; La radiation Cerenkov

Energy Technology Data Exchange (ETDEWEB)

Hubert, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

The influence of increased temperature of waters from Cernavoda NPP on underground water sources

International Nuclear Information System (INIS)

Isbasoiu, Eugen Constantin; Marinov, Anca Mariana; Moraru, Carina Nicoleta; Rizescu, Gheorghe

1997-01-01

The operation of Cernavoda NPP implies the change of thermal regime of waters in the Danube-Black Sea channel zone. The Danube water is used to cool the NPP systems before being delivered into channel and used in irrigations. The temperature increase of water in Cernavoda NPP installations is between 7 and 12 deg. C. The negative effects of this warming are: 1. limitation of water use for irrigations; 2. occurrence and persistence of fog in channel area; 3. thermal pollution of underground waters and limitation of underground potable water supply. The paper presents a general approach of thermal pollution problems of an aquifer and a mathematical model of forecasting the underground water temperature variation in Danube-Black Sea channel area. (authors)

SU-F-J-56: The Connection Between Cherenkov Light Emission and Radiation Absorbed Dose in Proton Irradiated Phantoms

Energy Technology Data Exchange (ETDEWEB)

Darafsheh, A; Kassaee, A; Finlay, J [University of Pennsylvania, Philadelphia, PA (United States); Taleei, R [UT Southwestern Medical Center, Dallas, TX (United States)

2016-06-15

Purpose: Range verification in proton therapy is of great importance. Cherenkov light follows the photon and electron energy deposition in water phantom. The purpose of this study is to investigate the connection between Cherenkov light generation and radiation absorbed dose in a water phantom irradiated with proton beams. Methods: Monte Carlo simulation was performed by employing FLUKA Monte Carlo code to stochastically simulate radiation transport, ionizing radiation dose deposition, and Cherenkov radiation in water phantoms. The simulations were performed for proton beams with energies in the range 50–600 MeV to cover a wide range of proton energies. Results: The mechanism of Cherenkov light production depends on the initial energy of protons. For proton energy with 50–400 MeV energy that is below the threshold (∼483 MeV in water) for Cherenkov light production directly from incident protons, Cherenkov light is produced mainly from the secondary electrons liberated as a result of columbic interactions with the incident protons. For proton beams with energy above 500 MeV, in the initial depth that incident protons have higher energy than the Cherenkov light production threshold, the light has higher intensity. As the slowing down process results in lower energy protons in larger depths in the water phantom, there is a knee point in the Cherenkov light curve vs. depth due to switching the Cherenkov light production mechanism from primary protons to secondary electrons. At the end of the depth dose curve the Cherenkov light intensity does not follow the dose peak because of the lack of high energy protons to produce Cherenkov light either directly or through secondary electrons. Conclusion: In contrast to photon and electron beams, Cherenkov light generation induced by proton beams does not follow the proton energy deposition specially close to the end of the proton range near the Bragg peak.

Getting the traces (FADCs) of a water Cherenkov detector signal

International Nuclear Information System (INIS)

Ponce, E.; Salazar, H.; Martinez, O.; Moreno, E.

2003-01-01

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 x 1014 to 1 x 1016 eV. 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

Context of surveillance of underground and surface waters

International Nuclear Information System (INIS)

2010-01-01

This document briefly describes the evolutions of regulations on site liquid effluents and of guideline values concerning radioactive wastes, briefly presents the surveillance of underground and surface waters of CEA sites, comments the guideline values of the radiological quality of waters aimed at human consumption, and gives an overview of information which are brought to public's attention. Then, for different CEA sites (Cadarache, Marcoule, Saclay, Grenoble, Fontenay-aux-Roses, Valduc, DIF), this document proposes a presentation of the hydrological context, regulatory context, the surface and underground water surveillance process and values, the storing zones of old wastes

Signal from Cyg X-3, as recorded in some underground experiments, real?

International Nuclear Information System (INIS)

Chudakov, A.E.

1986-01-01

Most of the excitement concerning the underground detection of signals from Cyg X-3 comes not from astrophysical grounds, but from the contradiction with surface experimental data. Believing in the Cyg X-3 signal underground and also that the main processes of muon production are well knownm the conclusion was drawn that the signal in EAS Cherenkov or counter experiments could be remarkably high, which is not the case. Possible solutions to this discrepancy are discussed

Solubility studies of Np(V) in simulated underground water

International Nuclear Information System (INIS)

Zhang Yingjie; Ren Lilong; Jiao Haiyang; Yao Jun; Su Xiguang; Fan Xianhua

2004-01-01

The solubility of Np(V) in simulated underground water has been measured with the variation of pH, storage time (0-100 days). All experiments were performed in an Ar glove box which contained high purity Ar, with an oxygen content of less than 5ppm. Experimental results show that the solubility of Np(V) in simulated underground water decreased with increasing pH value of solution; the solubility of Np(V) in simulated underground water determined at different pH is : pH=6.96, [Np(V)]=(3.52±0.37) x 10 -4 mol/L; pH=8.04, [Np(V)]=(8.24±0.32) x 10 -5 mol/L; pH=9.01, [Np(V)]=(3.04±0.48) x 10'- 5 mol/L, respectively. (author)

PPO-ethanol system as wavelength shifter for the Cherenkov counting technique using a liquid scintillation counter

International Nuclear Information System (INIS)

Takiue, M.; Fujii, H.; Ishikawa, H.

1984-01-01

2,5-diphenyloxazole (PPO) has been proposed as a wavelength shifter for Cherenkov counting. Since PPO is not incorporated with water, we have introduced the fluor into water in the form of micelle using a PPO-ethanol system. This technique makes it possible to obtain a high Cherenkov counting efficiency under stable sample conditions, attributed to the proper spectrometric features of the PPO. The 32 P Cherenkov counting efficiency (68.4%) obtained from this technique is 1.62 times as large as that measured with a conventional Cherenkov technique. (orig.)

The response of wavelength shifting panels in large water Cherenkov systems

International Nuclear Information System (INIS)

Bakich, A.M.; Peak, L.S.

1986-01-01

This paper describes a series of tests performed with a panel Bicron wavelength shifting acrylic plastic (BC-480) coupled to an EMI 9623B photomultiplier tube. The aim was to effectively increase the cathode coverage and its sensitivity to incident Cherenkov radiation, so that such a system could be employed in a solar neutrino detector. Measurements of the uniformity and effective efficiency of the system have been made and compared with the results of various simulation runs. The effects of side mirrors, back reflector, water interface and possible shaping of the panel to enhance its response are also assessed. (orig.)

Study on the optimization of the water Cherenkov detector array of the LHAASO project for surveying VHE gamma ray sources

Science.gov (United States)

Li, Hui-Cai; Chen, Ming-Jun; Jia, Huan-Yu; Gao, Bo; Wu, Han-Rong; Yao, Zhi-Guo; Yuo, Xiao-Hao; Zhou, Bin; Zhu, Feng-Rong

2014-01-01

It is prpopsed that a water Cherenkov detector array, LHAASO-WCDA, is to be built at Shangri-la, Yunnan Province, China. As one of the major components of the LHAASO project, the main purpose of it is to survey the northern sky for gamma ray sources in the energy range of 100 GeV-30 TeV. In order to design the water Cherenkov array efficiently to economize the budget, a Monte Carlo simulation is carried out. With the help of the simulation, the cost performance of different configurations of the array are obtained and compared with each other, serving as a guide for the more detailed design of the experiment in the next step.

Study on the optimization of the water Cherenkov detector array of the LHAASO project for surveying VHE gamma ray sources

International Nuclear Information System (INIS)

Li Huicai; Chen Mingjun; Gao Bo; Wu Hanrong; Yao Zhiguo; Zhou Bin; Jia Huanyu; Zhu Fengrong; You Xiaohao

2014-01-01

It is proposed that a water Cherenkov detector array, LHAASO-WCDA, is to be built at Shangri-la, Yunnan Province, China. As one of the major components of the LHAASO project, the main purpose of it is to survey the northern sky for gamma ray sources in the energy range of 100 GeV-30 TeV. In order to design the water Cherenkov array efficiently to economize the budget, a Monte Carlo simulation is carried out. With the help of the simulation, the cost performance of different configurations of the array are obtained and compared with each other, serving as a guide for the more detailed design of the experiment in the next step. (authors)

Character and levels of radioactive contamination of underground waters at Semipalatinsk test site

Energy Technology Data Exchange (ETDEWEB)

Subbotin, S.; Lukashenko, S.; Turchenko, Y. [Institute of radiation safety and ecology (Kazakhstan)

2014-07-01

According to the data of RK government commission, 470 explosions have been set off at the Semipalatinsk Test Site (STS), inclusive of 26 surface, 90 in the air and 354 underground nuclear explosions (UNE), 103 of those have been conducted in tunnels and 251 - in boreholes. Underground nuclear explosions have been conducted at STS in horizontal mines, called - 'tunnels' ('Degelen' test site) and vertical mines called 'boreholes' ('Balapan' and 'Sary-Uzen' test sites). Gopher cavities of boreholes and tunnels are in different geotechnical conditions, that eventually specify migration of radioactive products with underground waters. Central cavities of UNE in holes are located significantly below the level of distribution of underground water. High temperature remains for a long time due to presence of overlying rock mass. High temperatures contribute to formation of thermal convection. When reaching the cavity, the water heat up, dissolve chemical elements and radionuclides and return with them to the water bearing formation. In the major part of 'Balapan' site for underground water of regional basin is characterized by low concentrations of radionuclides. High concentrations of {sup 137}Cs in underground water have been found only in immediate vicinity to 'warfare' boreholes. Formation of radiation situation in the 'Balapan' test site area is also affected by local area of underground water discharge. It is located in the valley of Shagan creek, where the concentration of {sup 3}H reaches 700 kBq/l. Enter of underground water contaminated with tritium into surface water well continue. In this case it is expected that tritium concentration in discharge zone can significantly change, because this migration process depends on hydro geological factors and the amount of atmospheric precipitation. Central cavities of nuclear explosions, made in tunnels, are above the level of underground

Detection of underground water distribution piping system and leakages using ground penetrating radar (GPR)

Science.gov (United States)

Amran, Tengku Sarah Tengku; Ismail, Mohamad Pauzi; Ahmad, Mohamad Ridzuan; Amin, Mohamad Syafiq Mohd; Sani, Suhairy; Masenwat, Noor Azreen; Ismail, Mohd Azmi; Hamid, Shu-Hazri Abdul

2017-01-01

A water pipe is any pipe or tubes designed to transport and deliver water or treated drinking with appropriate quality, quantity and pressure to consumers. The varieties include large diameter main pipes, which supply entire towns, smaller branch lines that supply a street or group of buildings or small diameter pipes located within individual buildings. This distribution system (underground) is used to describe collectively the facilities used to supply water from its source to the point of usage. Therefore, a leaking in the underground water distribution piping system increases the likelihood of safe water leaving the source or treatment facility becoming contaminated before reaching the consumer. Most importantly, leaking can result in wastage of water which is precious natural resources. Furthermore, they create substantial damage to the transportation system and structure within urban and suburban environments. This paper presents a study on the possibility of using ground penetrating radar (GPR) with frequency of 1GHz to detect pipes and leakages in underground water distribution piping system. Series of laboratory experiment was designed to investigate the capability and efficiency of GPR in detecting underground pipes (metal and PVC) and water leakages. The data was divided into two parts: 1. detecting/locating underground water pipe, 2. detecting leakage of underground water pipe. Despite its simplicity, the attained data is proved to generate a satisfactory result indicating GPR is capable and efficient, in which it is able to detect the underground pipe and presence of leak of the underground pipe.

Tritium in the underground waters of the Karazheera coal deposit

International Nuclear Information System (INIS)

Panin, M.S.; Artamonova, H.N.

2001-01-01

Full text: The Karazheera coal deposit is the unique geological object due to it's location on the Balapan site of the former Semipalatinsk nuclear polygon (SNP) with its wide range of underground nuclear tests fulfilled here (more than 130 explosions). That is why some radiological problems may appear with the geological ones which take place in the open mining work of the deposit. The radio-active pollution of SNP has been actively discussed in scientific literature for a long time. The present report evaluates the radio-active tritium pollution ( 3 H) of the deposit's underground waters. That very component of nature is subjected to radiation pollution in large extent after underground nuclear tests. 3 H radio-active isotope with 12-13 year period of half-decay. 3 H is generated in the result of nuclear reactions caused by cosmic radiation and nuclear reactions of explosions. The total number of 3 H on the globe comes to 12 kg. The content of 3 H has been studied in underground waters of self-pouring wells number 76, 82, springs and dipholes of the deposit. It has been fixed that concentration of 3 H in the deposit is fluctuating within 0.4-37.9 tritium units (TU) while the average content 10.3 TU (1 TU - 3.2x10 -12 Curie/liter). The analysis of 3 H decay shows that its maximum concenliaiion has been fixed in the deposit 82 (37.9 TU) and in diphole (32.3 TU). The background content of 3 H in water was evaluated on the level of 1-8 TU till 1945. In the result of nuclear weapon tests the background has been considerably increased and according to First data (1994) it is corresponded to 23 TU. The average content of the 3 H in underground waters of Karazheera is half the size of this index (10.3 TU). It comprises 3.3x10 -11 and it is more lower than quota 4x10 -6 Ci/l. It is considered that the content of more than 10 TU in waters is caused by thermal nuclear test. Precipitations fallen after 1961 are presented in subsoil waters containing of 20 TU or more

Development of an underwater Cherenkov detector to reveal sources of technogenic radionuclides

International Nuclear Information System (INIS)

Chernyaev, A.M.; Gaponov, I.A.; Lapushkina, L.V.

1999-01-01

The major difference of the Cherenkov underwater detector from a scintillation detector is that its operation does not require a primary transducer (scintillator). Detected particle energy conversion into a light flash occurs directly in sea water (radiator) due to the Cherenkov effect. Consequently, photoreceiver of the underwater Cherenkov detector registers light from radiator of actually infinite volume. The circumstance is of principle importance, as it permits attaining the utmost sensitivity in case of the minimal overall dimensions and weight of detecting equipment

Application of machine learning techniques to lepton energy reconstruction in water Cherenkov detectors

Science.gov (United States)

Drakopoulou, E.; Cowan, G. A.; Needham, M. D.; Playfer, S.; Taani, M.

2018-04-01

The application of machine learning techniques to the reconstruction of lepton energies in water Cherenkov detectors is discussed and illustrated for TITUS, a proposed intermediate detector for the Hyper-Kamiokande experiment. It is found that applying these techniques leads to an improvement of more than 50% in the energy resolution for all lepton energies compared to an approach based upon lookup tables. Machine learning techniques can be easily applied to different detector configurations and the results are comparable to likelihood-function based techniques that are currently used.

Application of Cherenkov light observation to reactor measurements (2). Design and trial fabrication of Cherenkov light estimation system

International Nuclear Information System (INIS)

Yamamoto, Keiichi; Takeuchi, Tomoaki; Tsuchiya, Kunihiko; Hayashi, Takayasu; Kosuge, Fumiaki; Sano, Tadafumi

2015-11-01

Development of the reactor measurement system was started to obtain the real-time in-core nuclear and thermal information, where the quantitative measurement of brightness of Cherenkov light was investigated. This report summarized the results of design and trial fabrication of the Cherenkov light estimation system from thermal power evaluation from Cherenkov light image emitted from the fuel elements. The developed Cherenkov light estimation system was verified with the Cherenkov light image emitted from the fuels in the core of Kyoto University Research Reactor (KUR). From the results, the thermal power of the fuel elements evaluated from the brightness of the Cherenkov light observed by a CCD camera was almost the same as that of thermal power calculated from SRAC code. On the other hand, the evaluation values of some fuel elements were different from the calculation values. This, it is necessary to improve the observation method of Cherenkov light in the reactor and the evaluation method of the brightness of Cherenkov light. (author)

Design and operation problems related to water curtain system for underground water-sealed oil storage caverns

Directory of Open Access Journals (Sweden)

Zhongkui Li

2016-10-01

Full Text Available The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years' experiences obtained from the first large-scale (millions of cubic meters underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles

Detection of ultraviolet Cherenkov light from high energy cosmic ray atmospheric showers: A field test

International Nuclear Information System (INIS)

Bartoli, B.; Peruzzo, L.; Sartori, G.; Bedeschi, F.; Bertolucci, E.; Mariotti, M.; Menzione, A.; Ristori, L.; Stefanini, A.; Zetti, F.; Scribano, A.; Budinich, M.; Liello, F.

1991-01-01

We present the results of a test with a prototype apparatus aimed to detect the ultraviolet Cherenkov light in the wavelenght range 2000-2300A, emitted by high energy cosmic ray showers. The system consists of a gas proportional chamber, with TMAE vapour as the photosensitive element, placed on the focal plane of a 1.5 m diameter parabolic mirror. The test was done during the summer of 1989 with cosmic ray showers seen in coincidence with the EAS-TOP experiment, an extended atmospheric shower charged particle array now being exploited at Campo Imperatore, 1900 m above sea level, on top of the Gran Sasso underground Laboratory of INFN. The results were positive and show that a full scale ultraviolet Cherenkov experiment with good sensitivity, angular resolution and virtually no background from moonlight or even daylight can be envisaged. (orig.)

Progress in Cherenkov femtosecond fiber lasers

DEFF Research Database (Denmark)

Liu, Xiaomin; Svane, Ask Sebastian; Lægsgaard, Jesper

2016-01-01

systems are highlighted—dependent on the realization scheme, the Cherenkov lasers can generate the femtosecond output tunable across the entire visible and even the UV range, and for certain designs more than 40% conversion efficiency from the pump to Cherenkov signal can be achieved. The femtosecond......We review the recent developments in the field of ultrafast Cherenkov fiber lasers. Two essential properties of such laser systems—broad wavelength tunability and high efficiency of Cherenkov radiation wavelength conversion are discussed. The exceptional performance of the Cherenkov fiber laser...... Cherenkov laser with all-fiber architecture is presented and discussed. Operating in the visible range, it delivers 100–200 fs wavelength-tunable pulses with multimilliwatt output power and exceptionally low noise figure an order of magnitude lower than the traditional wavelength tunable supercontinuumbased...

The Cherenkov Bremsstrahlung

International Nuclear Information System (INIS)

Strel'tsov, V.N.

1995-01-01

The vanishing of the 'retardation factor' leads to a significant growth of the intensity of the electromagnetic field 'velocity part' of the moving charge. The Cherenkov radiation is its physical consequence. The same reason also conditions the growth of another term: the 'acceleration part' of the field which gives rise to the 'Cherenkov Bremsstrahlung'. 4 refs

Cherenkov and scintillation light separation on the CheSS experiment

Science.gov (United States)

Caravaca, Javier; Land, Benjamin; Descamps, Freija; Orebi Gann, Gabriel D.

2016-09-01

Separation of the scintillation and Cherenkov light produced in liquid scintillators enables outstanding capabilities for future particle detectors, the most relevant being: particle directionality information in a low energy threshold detector and improved particle identification. The CheSS experiment uses an array of small, fast photomultipliers (PMTs) and state-of-the-art electronics to demonstrate the reconstruction of a Cherenkov ring in liquid scintillator using two techniques: based on the photon density and using the photon hit time information. A charged particle ionizing a scintillation medium produces a prompt Cherenkov cone and late isotropic scintillation light, typically delayed by several ns. The fast response of our PMTs and DAQ provides a precision well below the ns level, making possible the time separation. Furthermore, the usage of the new developed water-based liquid scintillators (WbLS) enhances the separation since it allows tuning of the Cherenkov/Scintillation ratio. Latest results on the separation for pure liquid scintillators and WbLS will be presented.

Hydrogeochemistry of karst underground waters at shallow depth in Guiyang City, Guizhou Province

Institute of Scientific and Technical Information of China (English)

DONG Zhifen; ZHU Lijun; WU Pan; SHEN Zheng; FENG Zhiyong

2005-01-01

The aim of this study is to shed light on the hydrogeochemical characteristics of karst underground waters at shallow depth in Guiyang City, Guizhou Province with an emphasis on the geochemistry of major elements. Guiyang City bears abundant underground waters and it is also an important representative of the karst areas throughout the world. Ca 2+ and Mg 2+ are the dominant cations, accounting for 81%- 99.7% of the total, and HCO -3 and SO 2- 4 are the dominant anions. Weathering of limestones and dolostones is the most important factor controlling the hydrogeochemistry of underground waters, and weathering of sulfate and evaporite rocks is less important. Moreover, the precipitation and human activities also have a definite influence on the hydrogeochemistry of underground waters in the region studied.

Arsenic contamination of underground water in Bangladesh: cause, effect, separation, determination and remedy

International Nuclear Information System (INIS)

Ahmed, M.J.

2003-01-01

Arsenic contamination of underground water of Bangladesh has become the gravest concern for the lives of millions of people of this land. Probable causes and effects of arsenic contamination of underground water of Bangladesh have been extensively discussed. The extent of current knowledge regarding the specification of arsenic in environmental waters in delineated. A simple, non-extractive, highly sensitive and selective quench photometric methods for the rapid determination of arsenic at trace levels in aqueous medium has been developed. This paper also presents a short review of the technologies used for arsenic removal of underground water in Bangladesh. (author)

Cherenkov radiation in vacuum. 1

International Nuclear Information System (INIS)

Kozik, B.

1985-01-01

After discussing some historical aspects of the Cherenkov effect from electrodynamic and quantum theoretical points of view a methodically clear and simple theory of the Cherenkov effect is presented in which an arbitrary shaped rigid charge distribution is considered and which is based only on essential knowledge of Fourier transformations and cylindric functions. The Cherenkov effect is derived as a consequence of the structure of the potentials and the influence of the geometric shape of the charge distribution on the spectral distribution of the radiation intensity is taken into account in a general form. The educational value of such a representation of the Cherenkov effect in textbooks is emphasized

Tunable femtosecond Cherenkov fiber laser

DEFF Research Database (Denmark)

Liu, Xiaomin; Svane, Ask Sebastian; Lægsgaard, Jesper

2014-01-01

We demonstrate electrically-tunable femtosecond Cherenkov fiber laser output at the visible range. Using an all-fiber, self-starting femtosecond Yb-doped fiber laser as the pump source and nonlinear photonic crystal fiber link as the wave-conversion medium, ultrafast, milliwatt-level, tunable...... and spectral isolated Cherenkov radiation at visible wavelengths are reported. Such a femtosecond Cherenkov laser source is promising for practical biophotonics applications....

(Case Study: Underground Water Resources in Damghan Region

Directory of Open Access Journals (Sweden)

Gh Dashti

2010-05-01

Full Text Available The necessity of recognition and optimal exploitation of underground water sources results from the fact that these resources contribute to 99% of total useable soft water of the world. In our country the agricultural sector is the main user of water among different economic sectors. Therefore, applying scientific and appropriate management measures and approaches for desired utilization of this production factor is critical. Taking into account of real value of water in water management of agricultural sector can lead to development of motivation required for saving its usage and also helps  its optimal allocation in production. Generally, water has two types of real prices. One is supplier (producer point of view and the second includes demander perspective. In this study, real price of water from producer and demander point of views was determined by the use of production function approach for wheat production at underground water sources (wells of Damghan. The required data were collected from 184 farmers of Damghan in agricultural year 2007-08. According to superior production function(Generalized Quadratic, economic value of water in wheat production is 403.2 Iranian rials and this is more than the usual value in the area

Study of solar activity by measuring cosmic rays with a water Cherenkov detector

International Nuclear Information System (INIS)

Bahena Bias, Angelica; Villasenor, Luis

2011-01-01

We report on an indirect study of solar activity by using the Forbush effect which consists on the anti-correlation between the intensity of solar activity and the intensity of secondary cosmic radiation detected at ground level at the Earth. We have used a cylindrical water Cherenkov detector to measure the rate of arrival of secondary cosmic rays in Morelia Mich., Mexico, at 1950 m.a.s.l. We describe the analysis required to unfold the effect of atmospheric pressure and the search for Forbush decreases in our data, the latter correspond to more than one year of continuous data collection.

Applications of Cherenkov Light Emission for Dosimetry in Radiation Therapy

Science.gov (United States)

Glaser, Adam Kenneth

Since its discovery in the 1930's, the Cherenkov effect has been paramount in the development of high-energy physics research. It results in light emission from charged particles traveling faster than the local speed of light in a dielectric medium. The ability of this emitted light to describe a charged particle's trajectory, energy, velocity, and mass has allowed scientists to study subatomic particles, detect neutrinos, and explore the properties of interstellar matter. However, only recently has the phenomenon been considered in the practical context of medical physics and radiation therapy dosimetry, where Cherenkov light is induced by clinical x-ray photon, electron, and proton beams. To investigate the relationship between this phenomenon and dose deposition, a Monte Carlo plug-in was developed within the Geant4 architecture for medically-oriented simulations (GAMOS) to simulate radiation-induced optical emission in biological media. Using this simulation framework, it was determined that Cherenkov light emission may be well suited for radiation dosimetry of clinically used x-ray photon beams. To advance this application, several novel techniques were implemented to realize the maximum potential of the signal, such as time-gating for maximizing the signal to noise ratio (SNR) and Cherenkov-excited fluorescence for generating isotropic light release in water. Proof of concept experiments were conducted in water tanks to demonstrate the feasibility of the proposed method for two-dimensional (2D) projection imaging, three-dimensional (3D) parallel beam tomography, large field of view 3D cone beam tomography, and video-rate dynamic imaging of treatment plans for a number of common radiotherapy applications. The proposed dosimetry method was found to have a number of unique advantages, including but not limited to its non-invasive nature, water-equivalence, speed, high-resolution, ability to provide full 3D data, and potential to yield data in-vivo. Based on

Optical cone beam tomography of Cherenkov-mediated signals for fast 3D dosimetry of x-ray photon beams in water.

Science.gov (United States)

Glaser, Adam K; Andreozzi, Jacqueline M; Zhang, Rongxiao; Pogue, Brian W; Gladstone, David J

2015-07-01

To test the use of a three-dimensional (3D) optical cone beam computed tomography reconstruction algorithm, for estimation of the imparted 3D dose distribution from megavoltage photon beams in a water tank for quality assurance, by imaging the induced Cherenkov-excited fluorescence (CEF). An intensified charge-coupled device coupled to a standard nontelecentric camera lens was used to tomographically acquire two-dimensional (2D) projection images of CEF from a complex multileaf collimator (MLC) shaped 6 MV linear accelerator x-ray photon beam operating at a dose rate of 600 MU/min. The resulting projections were used to reconstruct the 3D CEF light distribution, a potential surrogate of imparted dose, using a Feldkamp-Davis-Kress cone beam back reconstruction algorithm. Finally, the reconstructed light distributions were compared to the expected dose values from one-dimensional diode scans, 2D film measurements, and the 3D distribution generated from the clinical Varian ECLIPSE treatment planning system using a gamma index analysis. A Monte Carlo derived correction was applied to the Cherenkov reconstructions to account for beam hardening artifacts. 3D light volumes were successfully reconstructed over a 400 × 400 × 350 mm(3) volume at a resolution of 1 mm. The Cherenkov reconstructions showed agreement with all comparative methods and were also able to recover both inter- and intra-MLC leaf leakage. Based upon a 3%/3 mm criterion, the experimental Cherenkov light measurements showed an 83%-99% pass fraction depending on the chosen threshold dose. The results from this study demonstrate the use of optical cone beam computed tomography using CEF for the profiling of the imparted dose distribution from large area megavoltage photon beams in water.

Effect of solid waste landfill on underground and surface water ...

African Journals Online (AJOL)

Effect of solid waste landfill on underground and surface water quality at ring road, Ibadan, Nigeria. ... parameters showed increased concentrations over those from control sites. ... Keywords: Landfill, groundwater, surface-water, pollution.

Specific features of auxiliary water supply at underground NPPs

International Nuclear Information System (INIS)

Pergamenshchik, B.K.; Pavlov, A.S.

1991-01-01

Specific features of auxiliary water supply systems for underground NPPs related to peculiarities of NPP basis equipment arrangement, are considered. Circulation water supply scheme, in which water cooling storage basin (cooling towers) with operational area corresponding to NPP power is on the surface and has traditional design, is proposed. Sufficiently high efficiency of the arrangement proposed is proved

An experimental study on cyclotron-Cherenkov radiation

Energy Technology Data Exchange (ETDEWEB)

Lee, C Y; Masuzaki, M; Yoshida, H; Toyosugi, N; Kamada, K; Ando, R [Kanazawa Univ. (Japan). Department of Physics

1997-12-31

Dielectric-loaded cylindrical waveguide configurations with an injected electron beam in which the growth rate of the cyclotron-Cherenkov instability surpasses that of the Cherenkov instability were sought by numerical treatment, and one configuration of this kind was found. This configuration consists of a metallic core and an outer metallic cylinder with a dielectric liner on the inner surface. Based on the calculations, an experimental device was designed and assembled to investigate experimentally radiation due to the cyclotron-Cherenkov instability. Beam propagation in the dielectric-loaded coaxial waveguide and microwave radiation due to the cyclotron-Cherenkov instability and the Cherenkov instability were studied. (author). 6 figs., 10 refs.

Studies on radon concentration in underground water samples in and around Kabini river basin

International Nuclear Information System (INIS)

Yashaswini, T.; Ningappa, C.; Niranjan, R.S.; Sannappa, J.

2017-01-01

Radon is a radioactive inert gas, a decay product of radium, causes environmental health problems like lung cancer. Radium present in the earth crest continuously releases radon into underground water. From the point view of health, the study of radon concentration level in underground water base line data is important. In the present study, radon concentration in underground water have been measured in 40 underground water samples collected in and around Kabini River of Karnataka State by using Emanometry technique. The radon concentration in the study area varies from 21.2 to 168.2Bq.l -1 with a geometrical mean value of 73.3 Bq.l -1 . The physicochemical parameters of water such as chloride, Fluoride, nitrite, sulphate, TDS are measured in the same samples in order to know about the impact of these parameters on radon concentration and their health risks to the general public. The experimental techniques and results obtained are discussed in the presentation. (author)

The Cherenkov Radiation for Non-Trivial Systems; La Radiacion Cherenkov en Sistemas No Triviales

Energy Technology Data Exchange (ETDEWEB)

Grau Carles, A.

2002-07-01

The charge pathways and the dielectric properties of the medium are two essential aspects to be considered in the study of the emission of Cherenkov radiation. We described the evolution of the Cherenkov wavefront when the charges follow circular or helical pathways. Also we derive expressions for the refractive Index in different transparent media (solid, liquid or gas), focusing our attention on optically active plasmas. The optical analogies between the plasma and the birefringent crystals is studied in detail. Finally, we list some examples of plasmas, which can be considered emitters of Cherenkov radiation. (Author) 52 refs.

Water pollution control for underground coal gasification

International Nuclear Information System (INIS)

Humenick, M.J.

1984-01-01

Water pollution arising from underground gasification of coal is one of the important considerations in the eventual commercialization of the process. Because many coal seams which are amenable to in situ gasification are also ground-water aquifers, contaminants may be released to these ground waters during and after gasification. Also, when product gas is processed above ground for use, wastewater streams are generated which are too polluted to be discharged. The purpose of this paper is to characterize the nature of the groundwater and above-ground pollutants, discuss the potential long and short-term effects on ground water, propose control and restoration strategies, and to identify potential wastewater treatment schemes

Development of a 13-in. Hybrid Avalanche Photo-Detector (HAPD) for a next generation water Cherenkov detector

International Nuclear Information System (INIS)

Nakayama, H.; Kusaka, A.; Kakuno, H.; Abe, T.; Iwasaki, M.; Aihara, H.; Shiozawa, M.; Tanaka, M.; Kyushima, H.; Suyama, M.; Kawai, Y.

2006-01-01

We have developed a 13-in. Hybrid Avalanche Photo-Detector (HAPD) for photosensors in next generation water Cherenkov type detectors. We study the performance of the HAPD and the results show good time resolution better than σ=1ns, good sensitivity for single photon detection, wide dynamic range, and good uniformity on the photocathode. The HAPD is also expected to be less expensive than large PMTs because of its simpler structure without dynodes

Asymmetric Cherenkov acoustic reverse in topological insulators

Science.gov (United States)

Smirnov, Sergey

2014-09-01

A general phenomenon of the Cherenkov radiation known in optics or acoustics of conventional materials is a formation of a forward cone of, respectively, photons or phonons emitted by a particle accelerated above the speed of light or sound in those materials. Here we suggest three-dimensional topological insulators as a unique platform to fundamentally explore and practically exploit the acoustic aspect of the Cherenkov effect. We demonstrate that by applying an in-plane magnetic field to a surface of a three-dimensional topological insulator one may suppress the forward Cherenkov sound up to zero at a critical magnetic field. Above the critical field the Cherenkov sound acquires pure backward nature with the polar distribution differing from the forward one generated below the critical field. Potential applications of this asymmetric Cherenkov reverse are in the design of low energy electronic devices such as acoustic ratchets or, in general, in low power design of electronic circuits with a magnetic field control of the direction and magnitude of the Cherenkov dissipation.

Measurement of Rn-222 concentration in underground water in Osaka stratum group in Sennan area

International Nuclear Information System (INIS)

Fukui, Masami; Katsurayama, Kosuke

1977-01-01

The Rn-222 concentration in underground water is reported as follows, which is the result obtained when the ground inspection was carried out in the Research Reactor Institute of Kyoto University located at Kumatori area in Osaka stratum group. Underground water, at different depth, well water and rain water were taken, and the contained Rn-222 was extracted with toluene to measure by liquid scintillation technique. Rn-222 concentration in rain water was 3.5 - 8.0 pCi/l, while the concentration in well water was 130 - 250 pCi/l, and that in underground water was 240 - 313 pCi/l. The seasonal change, geographical difference and variation according to depth of Rn-222 concentration were examined. Rn-222 behavior in soil should be investigated more in detail in reference to Rn-222 dispersion, transport and equilibrium problems in soil-water system in the future. (Kobatake, H.)

Radium balance in discharge waters from coal mines in Poland the ecological impact of underground water treatment

International Nuclear Information System (INIS)

Chalupnik, S.; Wysocka, M.

2008-01-01

Saline waters from underground coal mines in Poland often contain natural radioactive isotopes, mainly 226 Ra from the uranium decay series and 228 Ra from the thorium series. More than 70% of the total amount of radium remains underground as radioactive deposits due to spontaneous co-precipitation or water treatment technologies, but several tens of MBq of 226 Ra and even higher activity of 228 Ra are released daily into the rivers along with the other mine effluents from all Polish coal mines. Mine waters can have a severe impact on the natural environment, mainly due to its salinity. Additionally high levels of radium concentration in river waters, bottom sediments and vegetation were also observed. Sometimes radium concentrations in rivers exceeded 0.7 kBq/m 3 , which was the permitted level for wastewaters under Polish law. The investigations described here were carried out for all coal mines and on this basis the total radium balance in effluents has been calculated. Measurements in the vicinity of mine settling ponds and in rivers have given an opportunity to study radium behaviour in river waters and to assess the degree of contamination. For removal of radium from saline waters a method of purification has been developed and implemented in full technical scale in two of Polish coal mines. The purification station in Piast Colliery was unique, the first underground installation for the removal of radium isotopes from saline waters. Very good results have been achieved - approximately 6 m 3 /min of radium-bearing waters were treated there, more than 100 MBq of 226 Ra and 228 Ra remained underground each day. Purification has been started in 1999, therefore a lot of experiences have been gathered during this period. Since year 2006, a new purification station is working in another colliery, Ziemowit, at the level -650 meters. Barium chloride is used as a cleaning , agent, and amount of water to be purified is reaching 9 m 3 /min. Technical measures such as

Monitoring underground water leakage pattern by ground penetrating radar (GPR) using 800 MHz antenna frequency

Science.gov (United States)

Amran, T. S. T.; Ismail, M. P.; Ahmad, M. R.; Amin, M. S. M.; Ismail, M. A.; Sani, S.; Masenwat, N. A.; Basri, N. S. M.

2018-01-01

Water is the most treasure natural resources, however, a huge amount of water are lost during its distribution that leads to water leakage problem. The leaks meant the waste of money and created more economic loss to treat and fix the damaged pipe. Researchers and engineers have put tremendous attempts and effort, to solve the water leakage problem especially in water leakage of buried pipeline. An advanced technology of ground penetrating radar (GPR) has been established as one of the non-destructive testing (NDT) method to detect the underground water pipe leaking. This paper focuses on the ability of GPR in water utility field especially on detection of water leaks in the underground pipeline distribution. A series of laboratory experiments were carried out using 800-MHz antenna, where the performance of GPR on detecting underground pipeline and locating water leakage was investigated and validated. A prototype to recreate water-leaking system was constructed using a 4-inch PVC pipe. Different diameter of holes, i.e. ¼ inch, ½ inch, and ¾ inch, were drilled into the pipe to simulate the water leaking. The PVC pipe was buried at the depth of 60 cm into the test bed that was filled with dry sand. 15 litres of water was injected into the PVC pipe. The water leakage patterns in term of radargram data were gathered. The effectiveness of the GPR in locating the underground water leakage was ascertained, after the results were collected and verified.

Study on underground-water restoration of acid in-situ leaching process with electrodialytic desalination

International Nuclear Information System (INIS)

Huang Chongyuan; Meng Jin; Li Weicai

2003-01-01

The study focus undergrounder water restoration of acid in-situ leaching process with electrodialysis desalination in Yining Uranium Mine. It is shown in field test that electrodialysis desalination is an effective method for underground water restoration of acid in-situ leaching process. When TDS of underground-water at the decommissioning scope is 10-12 g/L, and TDS will be less than 1 g/L after the desalination process, the desalination rate is more than 90%, freshwater recovery 60%-70%, power consumption for freshwater recovery 5 kW·h/m 3 , the distance of the desalination flow 12-13 m, current efficiency 80%, and the throughput of the twin membrane 0.22-0.24 m 3 /(m 2 ·d)

Technical Note: On maximizing Cherenkov emissions from medical linear accelerators.

Science.gov (United States)

Shrock, Zachary; Yoon, Suk W; Gunasingha, Rathnayaka; Oldham, Mark; Adamson, Justus

2018-04-19

Cherenkov light during MV radiotherapy has recently found imaging and therapeutic applications but is challenged by relatively low fluence. Our purpose is to investigate the feasibility of increasing Cherenkov light production during MV radiotherapy by increasing photon energy and applying specialized beam-hardening filtration. GAMOS 5.0.0, a GEANT4-based framework for Monte Carlo simulations, was used to model standard clinical linear accelerator primary photon beams. The photon source was incident upon a 17.8 cm 3 cubic water phantom with a 94 cm source to surface distance. Dose and Cherenkov production was determined at depths of 3-9 cm. Filtration was simulated 15 cm below the photon beam source. Filter materials included aluminum, iron, and copper with thicknesses of 2-20 cm. Histories used depended on the level of attenuation from the filter, ranging from 100 million to 2 billion. Comparing average dose per history also allowed for evaluation of dose-rate reduction for different filters. Overall, increasing photon beam energy is more effective at improving Cherenkov production per unit dose than is filtration, with a standard 18 MV beam yielding 3.3-4.0× more photons than 6 MV. Introducing an aluminum filter into an unfiltered 2400 cGy/min 10 MV beam increases the Cherenkov production by 1.6-1.7×, while maintaining a clinical dose rate of 300 cGy/min, compared to increases of ~1.5× for iron and copper. Aluminum was also more effective than the standard flattening filter, with the increase over the unfiltered beam being 1.4-1.5× (maintaining 600 cGy/min dose rate) vs 1.3-1.4× for the standard flattening filter. Applying a 10 cm aluminum filter to a standard 18 MV, photon beam increased the Cherenkov production per unit dose to 3.9-4.3× beyond that of 6 MV (vs 3.3-4.0× for 18 MV with no aluminum filter). Through a combination of increasing photon energy and applying specialized beam-hardening filtration, the amount of Cherenkov photons per

On the fine structure of the Vavilov-Cherenkov radiation

International Nuclear Information System (INIS)

Afanas'ev, G.N.; Kartavenko, V.G.; Zrelov, V.P.

2003-01-01

The aim of this paper is to study the fine structure of the Cherenkov rings. We analyze Zrelov's experiments in which the Cherenkov radiation was detected without using the special focusing devices. The broad Cherenkov ring was observed in the plane perpendicular to the motion axis. Using the exact and approximate formulae, we investigate how a charge uniformly moving in a medium radiates in a finite space interval. The formulae obtained describe the radiation intensity in the whole space interval, inside and outside the Cherenkov ring. In the plane perpendicular to the motion axis, the radiation fills mainly the finite ring. Its width, proportional to the motion interval, and the energy released in this ring do not depend on the position of the observation plane. Outside the Cherenkov ring, the radiation intensity suddenly drops. Inside it, the radiation intensity exhibits small oscillations which are due to the interference of the Vavilov-Cherenkov radiation and bremsstrahlung. The increase in the radiation intensity at the ends of the Cherenkov ring is associated with the shock waves arising at the beginning and the end of the charge motion and at the moments when the charge velocity coincides with the light velocity in a medium. For the chosen motion interval, the well-known Tamm formula does not describe the radiation intensity inside the Cherenkov ring for any position of the observation plane. Outside the Cherenkov ring, the Tamm formula is valid only at very large observation distances. Theoretical calculations are in satisfactory agreement with experimental data. Thus, the combined experimental and theoretical study of the unfocused Cherenkov rings allows one to obtain information on the physical processes accompanying the Cherenkov radiation (bremsstrahlung, transition of the light velocity barrier, etc.)

Water quality restoration during and after flooding of the underground Banat mines

International Nuclear Information System (INIS)

Iuhas, T.; Bragadireanu, M.; Filip, D.; Dumitrescu, N.

2001-01-01

Closing out and flooding of the underground Banat mines are priority concerns of the Uranium National Company S.A during the period 2000-2007, the economical uranium ores being exhausted after some 45 years of underground exploitation. Water quality restoration during the flooding process and after its completion was a part of a pilot project undertaken in the frame of a PHARE programme. The mines have two water treatment plants in operation with four modules with 3 ion exchange columns each, being in exploitation. The long term plans for the remediation of uranium mines will stop the Ciudanovita water treatment facility, all the underground mine waters being further pumped and treated within a single plant located at Lisava. The exploitation of the treatment plant will be ensured as long as needed, with a first foreseen period of ten years after total flooding of the Banat mines, linked with a long term environment monitoring programme. Necessary measures to be taken for ensuring the foreseen both uranium and radium separation are presented within this paper. Proposals for radium removal are present as a decision should be taken in the nearest future. (orig.)

Remote Cherenkov imaging-based quality assurance of a magnetic resonance image-guided radiotherapy system.

Science.gov (United States)

Andreozzi, Jacqueline M; Mooney, Karen E; Brůža, Petr; Curcuru, Austen; Gladstone, David J; Pogue, Brian W; Green, Olga

2018-06-01

Tools to perform regular quality assurance of magnetic resonance image-guided radiotherapy (MRIgRT) systems should ideally be independent of interference from the magnetic fields. Remotely acquired optical Cherenkov imaging-based dosimetry measurements in water were investigated for this purpose, comparing measures of dose accuracy, temporal dynamics, and overall integrated IMRT delivery. A 40 × 30.5 × 37.5 cm 3 water tank doped with 1 g/L of quinine sulfate was imaged using an intensified charge-coupled device (ICCD) to capture the Cherenkov emission while being irradiated by a commercial MRIgRT system (ViewRay™). The ICCD was placed down-bore at the end of the couch, 4 m from treatment isocenter and behind the 5-Gauss line of the 0.35-T MRI. After establishing optimal camera acquisition settings, square beams of increasing size (4.2 × 4.2 cm 2 , 10.5 × 10.5 cm 2 , and 14.7 × 14.7 cm 2 ) were imaged at 0.93 frames per second, from an individual cobalt-60 treatment head, to develop projection measures related to percent depth dose (PDD) curves and cross beam profiles (CPB). These Cherenkov-derived measurements were compared to ionization chamber (IC) and radiographic film dosimetry data, as well as simulation data from the treatment planning system (TPS). An intensity-modulated radiotherapy (IMRT) commissioning plan from AAPM TG-119 (C4:C-Shape) was also imaged at 2.1 frames per second, and the single linear sum image from 509 s of plan delivery was compared to the dose volume prediction generated by the TPS using gamma index analysis. Analysis of standardized test target images (1024 × 1024 pixels) yielded a pixel resolution of 0.37 mm/pixel. The beam width measured from the Cherenkov image-generated projection CBPs was within 1 mm accuracy when compared to film measurements for all beams. The 502 point measurements (i.e., pixels) of the Cherenkov image-based projection percent depth dose curves (pPDDs) were compared to p

Performance of aerogel as Cherenkov radiator

International Nuclear Information System (INIS)

Bellunato, T.; Calvi, M.; Matteuzzi, C.; Musy, M.; Negri, P.; Braem, A.; Chesi, E.; Hansen, C.; Liko, D.; Joram, C.; Neufeld, N.; Seguinot, J.; Weilhammer, P.; Buzykaev, A.R.; Kravchenko, E.A.; Onuchin, A.P.; Danilyuk, A.F.; Easo, S.; Wotton, S.; Jolly, S.

2004-01-01

Aerogel with index of refraction around 1.03 has been studied as Cherenkov radiator in a test at CERN PS using a π - and a mixed π + /p beam of momenta between 6 and 10 GeV/c. The Cherenkov photons were detected by means of four large HPD tubes designed and constructed at CERN. Results on the photoelectron yield, the Cherenkov angle and its resolution, and the π/p separation are obtained. The performances measured demonstrate that a RICH with aerogel is a viable detector for experiments with high multiplicity of particles in the final state

Particle Identification in Cherenkov Detectors using Convolutional Neural Networks

CERN Document Server

Theodore, Tomalty

2016-01-01

Cherenkov detectors are used for charged particle identification. When a charged particle moves through a medium faster than light can propagate in that medium, Cherenkov radiation is released in the shape of a cone in the direction of movement. The interior of the Cherenkov detector is instrumented with PMTs to detect this Cherenkov light. Particles, then, can be identified by the shapes of the images on the detector walls.

Analysis of Cherenkov counter efficiencies for E691

International Nuclear Information System (INIS)

Cremaldi, L.; Elliott, J.; Gibney, M.; Nauenberg, U.

1985-01-01

A program is outlined which simulates Cherenkov counters. The program can compute the effect of the magnetic field on the efficiencies of Cherenkov counters. It also tells what cone to mirror distance gives the highest collection efficiency and at which target position should the laser be placed to represent the direction of the actual Cherenkov light the mirror sees

Mechano-Magnetic Telemetry for Underground Water Infrastructure Monitoring

Directory of Open Access Journals (Sweden)

Daniel Orfeo

2018-06-01

Full Text Available This study reports on the theory of operation, design principles, and results from laboratory and field tests of a magnetic telemetry system for communication with underground infrastructure sensors using rotating permanent magnets as the sources and compact magnetometers as the receivers. Many cities seek ways to monitor underground water pipes with centrally managed Internet of Things (IoT systems. This requires the development of numerous reliable low-cost wireless sensors, such as moisture sensors and flow meters, which can transmit information from subterranean pipes to surface-mounted receivers. Traditional megahertz radio communication systems are often unable to penetrate through multiple feet of earthen and manmade materials and have impractically large energy requirements which preclude the use of long-life batteries, require complex (and expensive built-in energy harvesting systems, or long leads that run antennas near to the surface. Low-power magnetic signaling systems do not suffer from this drawback: low-frequency electromagnetic waves readily penetrate through several feet of earth and water. Traditional magnetic telemetry systems that use energy-inefficient large induction coils and antennas as sources and receivers are not practical for underground IoT-type sensing applications. However, rotating a permanent magnet creates a completely reversing oscillating magnetic field. The recent proliferation of strong rare-earth permanent magnets and high-sensitivity magnetometers enables alternative magnetic telemetry system concepts with significantly more compact formats and lower energy consumption. The system used in this study represents a novel combination of megahertz radio and magnetic signaling techniques for the purposes of underground infrastructure monitoring. In this study, two subterranean infrastructure sensors exploit this phenomenon to transmit information to an aboveground radio-networked magnetometer receiver. A flow

Application of Cherenkov light observation to reactor measurements (1). Estimation of reactor power from Cherenkov light intensity

International Nuclear Information System (INIS)

Yamamoto, Keiichi; Takeuchi, Tomoaki; Kimura, Nobuaki; Ohtsuka, Noriaki; Tsuchiya, Kunihiko; Sano, Tadafumi; Nakajima, Ken; Homma, Ryohei; Kosuge, Fumiaki

2015-01-01

Development of the reactor measurement system was started to obtain the real-time in-core nuclear and thermal information, where the quantitative measurement of brightness of Cherenkov light was investigated. The system would be applied as a monitoring system in severe accidents and for the advanced operation management technology in existing LWRs. The calculation and the observation were performed to obtain the quantity of the Cherenkov light caused by the gamma and beta rays emitted from the fuels in the core of Kyoto University Research Reactor. The results indicate that the real-time reactor power can be estimated from the brightness of the Cherenkov light observed by a CCD camera. This method can also work for the estimation of the burn-up of spent fuels at commercial reactors. Since the observed brightness value of the Cherenkov light was influenced by the camera position, the optical observation method should be improved to achieve high accuracy observation. (author)

All-fiber femtosecond Cherenkov radiation source

DEFF Research Database (Denmark)

Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe

2012-01-01

-conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580–630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such an all-fiber Cherenkov radiation source is promising for practical applications in biophotonics...

The Cherenkov Surface Detector of the Pierre Auger Observatory

Energy Technology Data Exchange (ETDEWEB)

Billoir, Pierre, E-mail: billoir@lpnhe.in2p3.fr [LPNHE, CNRS/IN2P3 and Univ. P. and M. Curie and Univ. D. Diderot, 4 place Jussieu 75272 Paris Cedex 05 (France); Observatorio Pierre Auger, av. San Martín Norte, 304 5613, Malargüe (Argentina)

2014-12-01

The Pierre Auger Observatory detects the atmospheric showers induced by cosmic rays of ultra-high energy (UHE). It is the first one to use the hybrid technique. A set of telescopes observes the fluorescence of the nitrogen molecules on clear moonless nights, giving access to the longitudinal profile of the shower. These telescopes surround a giant array of 1600 water Cherenkov tanks (covering more than 3000 km{sup 2}), which works continuously and samples the particles reaching the ground (mainly muons, photons and electrons/positrons); the light produced within the water is recorded into FADC (Fast Analog to Digital Convertes) traces. A subsample of hybrid events provides a cross calibration of the two components. We describe the structure of the Cherenkov detectors, their sensitivity to different particles and the information they can give on the direction of origin, the energy and the nature of the primary UHE object; we discuss also their discrimination power for rare events (UHE photons or neutrinos). To cope with the variability of weather conditions and the limitations of the communication system, the procedures for trigger and real time calibration have been shared between local processors and a central acquisition system. The overall system has been working almost continuously for 10 years, while being progressively completed and increased by the creation of a dense “infill” subarray. - Highlights: • The water Cherenkov technique is used in the Surface Detector of the Pierre Auger Observatory. • Cross-calibrated with the Fluorescence Detector, it provides a measurement of the primary energy. • The spectrum of the UHE cosmic rays exhibits clearly an “ankle” and a cutoff. • The muon observed muon content of the atmospheric showers is larger than expected from the models. • Stringent limits on the flux of UHE neutrinos and photons are obtained.

A study to measure νsub(μ)-e scattering with a water Cherenkov detector

International Nuclear Information System (INIS)

Candelle, J.M.

1985-11-01

A new technique is proposed to study the elastic diffusion νsub(μ)e. This technique consists in collecting the Cherenkov light created by the charged particles in a water tank. This method was tested at CERN, with electron, muon, pion, and gamma beams. The aim of the test was to know if it is possible to measure precisely the diffusion angle of electrons with a good electron-hadron, and electron-gamma discrimination. We obtained a very good angular resolution, close to 6 mrd√E(GeV). The hadronic rejection rate is close to 10 -3 . The electron-gamma discrimination is less clear; for an electron acceptance of 80%, the gamma rejection factor is equal to 5. Furthermore, the data are consistent with the number of 50 photo-electrons emitted in the water by centimeter. This technique could be used to measure sin 2 thetasub(w) with an absolute precision of 0.005 [fr

A large area plastic Cherenkov detector

International Nuclear Information System (INIS)

Bernabei, R.; Bidoli, V.; Zorzi, G. de; Biagio, A. di

1978-01-01

A large area Cherenkov counter has been built up using as a radiator a sheet of Pilot 425 plastic, (180x20)cm 2 x2.5 cm. Experimental tests performed with a pion beam in order to measure the average number of photoelectrons collected by photomultipliers and the scintillation to Cherenkov light ratio. (Auth.)

FACT. Bokeh alignment for Cherenkov telescopes

Energy Technology Data Exchange (ETDEWEB)

Mueller, Sebastian Achim [ETH Zurich (Switzerland); Buss, Jens [TU Dortmund (Germany)

2016-07-01

Imaging Atmospheric Cherenkov Telescopes (IACTs) need fast and large imaging optics to map the faint Cherenkov light emitted in cosmic ray air showers onto their image sensors. Segmented reflectors are inexpensive, lightweight and offer good image quality. However, alignment of the mirror facets remains a challenge. A good alignment is crucial in IACT observations to separate gamma rays from hadronic cosmic rays. We present a simple, yet extendable method, to align segmented reflectors using their Bokeh. Bokeh alignment does not need a star or good weather nights but can be done anytime, even during the day. Bokeh alignment optimizes the facet orientations by comparing the segmented reflector's Bokeh to a predefined template. The Bokeh is observed using the out of focus image of a nearby point like light source in a distance of about ten times the focal lengths. We introduce Bokeh alignment on segmented reflectors and present its use on the First Geiger-mode Avalanche Cherenkov Telescope (FACT) on Canary Island La Palma, as well as on the Cherenkov Telescope Array (CTA) Medium Size Telescope (MST) prototype in Berlin Adlershof.

Measurement of radionuclides in the environment via Cherenkov radiation

International Nuclear Information System (INIS)

Ross, H.H.

1987-01-01

The author has developed an alternate approach to the measurement of some beta-emitting nuclides that utilizes the luminescence generated by the Cherenkov process. The luminescence, now known as Cherenkov radiation, was shown to be generated when a charged particle passes through a transparent medium at a speed that exceeds the phase velocity of light in the same medium. Cherenkov emission is different from most other luminescence processes in that it is a purely physical phenomenon. One consequence of this is that Cherenkov systems are free of chemical quenching effects. Conventional methods of analysis for environmental levels of beta-emitting radionuclides are often tedious, time-consuming, and expensive. The Cherenkov method is fast, requires very little operator attention, and is much less expensive to perform

Optical fiber Cherenkov detector for beam current monitoring

International Nuclear Information System (INIS)

Pishchulin, I.V.; Solov'ev, N.G.; Romashkin, O.B.

1991-01-01

The results obtained in calculation of an optical fiber Cherenkov detector for accelerated beam current monitoring are presented. The technique of beam parameters monitoring is based on Cherenkov radiation excitation by accelerated electrons in the optical fiber. The formulas for calculations of optical power and time dependence of Cherenkov radiation pulse are given. The detector sensitivity and time resolution dependence on the fiber material characteristics are investigated. Parameters of a 10μm one-mode quartz optical fiber detector for the free electron laser photoinjector are calculated. The structure of a monitoring system with the optical fiber Cherenkov detector is considered. Possible applications of this technique are discussed and some recommendations are given

TU-AB-BRA-12: Quality Assurance of An Integrated Magnetic Resonance Image Guided Adaptive Radiotherapy Machine Using Cherenkov Imaging

Energy Technology Data Exchange (ETDEWEB)

Andreozzi, J; Bruza, P; Saunders, S; Pogue, B [Dartmouth College, Hanover, NH (United States); Mooney, K; Curcuru, A; Green, O [Washington University School of Medicine, Saint Louis, MO (United States); Gladstone, D [Dartmouth-Hitchcock Med. Ctr., Lebanon, NH (Lebanon)

2016-06-15

Purpose: To investigate the viability of using Cherenkov imaging as a fast and robust method for quality assurance tests in the presence of a magnetic field, where other instruments can be limited. Methods: Water tank measurements were acquired from a clinically utilized adaptive magnetic resonance image guided radiation therapy (MR-IGRT) machine with three multileaf-collimator equipped 60Co sources. Cherenkov imaging used an intensified charge coupled device (ICCD) camera placed 3.5m from the treatment isocenter, looking down the bore of the 0.35T MRI into a water tank. Images were post-processed to make quantitative comparison between Cherenkov light intensity with both film and treatment planning system predictions, in terms of percent depth dose curves as well as lateral beam profile measurements. A TG-119 commissioning test plan (C4: C-Shape) was imaged in real-time at 6.33 frames per second to investigate the temporal and spatial resolution of the Cherenkov imaging technique. Results: A .33mm/pixel Cherenkov image resolution was achieved across 1024×1024 pixels in this setup. Analysis of the Cherenkov image of a 10.5×10.5cm treatment beam in the water tank successfully measured the beam width at the depth of maximum dose within 1.2% of the film measurement at the same point. The percent depth dose curve for the same beam was on average within 2% of ionization chamber measurements for corresponding depths between 3–100mm. Cherenkov video of the TG-119 test plan provided qualitative agreement with the treatment planning system dose predictions, and a novel temporal verification of the treatment. Conclusions: Cherenkov imaging was successfully used to make QA measurements of percent depth dose curves and cross beam profiles of MRI-IGRT radiotherapy machines after only several seconds of beam-on time and data capture; both curves were extracted from the same data set. Video-rate imaging of a dynamic treatment plan provided new information regarding temporal

Safety distance between underground natural gas and water pipeline facilities

International Nuclear Information System (INIS)

Mohsin, R.; Majid, Z.A.; Yusof, M.Z.

2014-01-01

A leaking water pipe bursting high pressure water jet in the soil will create slurry erosion which will eventually erode the adjacent natural gas pipe, thus causing its failure. The standard 300 mm safety distance used to place natural gas pipe away from water pipeline facilities needs to be reviewed to consider accidental damage and provide safety cushion to the natural gas pipe. This paper presents a study on underground natural gas pipeline safety distance via experimental and numerical approaches. The pressure–distance characteristic curve obtained from this experimental study showed that the pressure was inversely proportional to the square of the separation distance. Experimental testing using water-to-water pipeline system environment was used to represent the worst case environment, and could be used as a guide to estimate appropriate safety distance. Dynamic pressures obtained from the experimental measurement and simulation prediction mutually agreed along the high-pressure water jetting path. From the experimental and simulation exercises, zero effect distance for water-to-water medium was obtained at an estimated horizontal distance at a minimum of 1500 mm, while for the water-to-sand medium, the distance was estimated at a minimum of 1200 mm. - Highlights: • Safe separation distance of underground natural gas pipes was determined. • Pressure curve is inversely proportional to separation distance. • Water-to-water system represents the worst case environment. • Measured dynamic pressures mutually agreed with simulation results. • Safe separation distance of more than 1200 mm should be applied

[Contamination and ecological risk assessment of polycyclic aromatic hydrocarbons in water and in Karst underground river catchment].

Science.gov (United States)

Lan, Jia-Cheng; Sun, Yu-Chuan; Tian, Ping; Lu, Bing-Qing; Shi, Yang; Xu, Xin; Liang Zuo-Bing; Yang, Ping-Heng

2014-10-01

Water samples in Laolongdong underground river catchment were collected to determine the concentration, compositional profiles, and evaluate ecological risk of 16 priority polycyclic aromatic hydrocarbons (PAHs). PAHs were measured by GC/MS. The total concentrations of 16 PAH ranged from 81.5-8019 ng · L(-1) in underground river, 288.7-15,200 ng · L(-1) in karst springs, and 128.4-2,442 ng · L(-1) in surface water. Affected by waste water from Huangjueya town, concentrations of PAHs in underground river were higher than those in surface water and waste water from sinkhole. The PAHs profiles were dominated by 3 ring PAHs. There were differences of monthly variations of PAHs contents in the water, due to waste water, season and different characteristics of PAH. Surface water and waste water from sinkhole played an important role on contamination in the river. The levels of ecological risk were generally moderately polluted and heavily polluted according to all detected PAH compounds in the water.

Spontaneous emission in Cherenkov FEL devices

International Nuclear Information System (INIS)

Ciocci, F.; Dattoli, G.; Doria, A.; Schettini, G.; Torre, A.; Walsh, J.E.

1987-01-01

The main features of the spectral characteristics of the spontaneously emitted Cherenkov light in circular and rectangular wave-guides filled with dielectric are discussed. The characteristics of the radiation emitted by an electron beam moving near and parallel to the surface of a dielectric slab are also analysed. Finally, the relevance of these results to a possible FEL-Cherenkov operation is briefly discussed

The Cherenkov Radiation for Non-Trivial Systems

International Nuclear Information System (INIS)

Grau Carles, A.

2002-01-01

The charge pathways and the dielectric properties of the medium are two essential aspects to be considered in the study of the emission of Cherenkov radiation. We described the evolution of the Cherenkov wavefront when the charges follow circular or helical pathways. Also we derive expressions for the refractive Index in different transparent media (solid, liquid or gas), focusing our attention on optically active plasmas. The optical analogies between the plasma and the birefringent crystals is studied in detail. Finally, we list some examples of plasmas, which can be considered emitters of Cherenkov radiation. (Author) 52 refs

Influence of surface water accumulations of the Stupnica creek on underground coal mining in the Durdevic coal mine

Energy Technology Data Exchange (ETDEWEB)

Valjarevic, R; Urosevic, V

1986-01-01

Discusses hydrological, geological and mining conditions at the Durdevic underground coal mine. A landslide at a spoil bank dammed the creek flowing above the mine. Two exploratory boreholes (62 m and 68 m) were drilled for hydrological investigations. Water coloring techniques, chemical water analysis, measurement of underground water level and water flow were used to determine whether a sudden inrush of rainfall and accumulated surface water could endanger the mine. Underground water inflow to mine rooms varies from 110-200 m/sup 3//min, depending on the season. Diversion of the creek bed with the accumulated water and accumulation and subsequent drainage of surface water via large diameter concrete pipes were considered as possible ways of improving safety in the mine. Details of these projects are included. 4 refs.

Charged particle identification: Cherenkov counters at ISABELLE

International Nuclear Information System (INIS)

Etkin, A.; Kostoulas, I.; Leith, D.W.G.S.; Thun, R.

1977-01-01

A brief summary is given of a study of Cherenkov counters for ISABELLE. The study was certainy not exhaustive and was meant primarily to suggest future detector development. A substantial research effort is needed in order to insure that Cherenkov counters utilizing photoionization are fully exploited

Aerogel as Cherenkov radiator for RICH detectors

International Nuclear Information System (INIS)

Bellunato, T.; Braem, A.; Buzykaev, A.R.; Calvi, M.; Chesi, E.; Danilyuk, A.F.; Easo, S.; Hansen, C.; Jolly, S.; Joram, C.; Kravchenko, E.A.; Liko, D.; Matteuzzi, C.; Musy, M.; Negri, P.; Neufeld, N.; Onuchin, A.P.; Seguinot, J.; Weilhammer, P.; Wotton, S.

2003-01-01

We present here the results obtained using silica aerogel as Cherenkov radiator for the separation and identification of particles in the momentum range from 6 to 10 GeV/c. Photoelectron yield and Cherenkov ring resolution were studied under different experimental conditions and compared to the simulation

Use of water-Cherenkov detectors to detect Gamma Ray Bursts at the Large Aperture GRB Observatory (LAGO)

International Nuclear Information System (INIS)

Allard, D.; Allekotte, I.; Alvarez, C.; Asorey, H.; Barros, H.; Bertou, X.; Burgoa, O.; Gomez Berisso, M.; Martinez, O.; Miranda Loza, P.; Murrieta, T.; Perez, G.; Rivera, H.; Rovero, A.; Saavedra, O.; Salazar, H.; Tello, J.C.; Ticona Peralda, R.; Velarde, A.; Villasenor, L.

2008-01-01

The Large Aperture GRB Observatory (LAGO) project aims at the detection of high energy photons from Gamma Ray Bursts (GRB) using the single particle technique in ground-based water-Cherenkov detectors (WCD). To reach a reasonable sensitivity, high altitude mountain sites have been selected in Mexico (Sierra Negra, 4550 m a.s.l.), Bolivia (Chacaltaya, 5300 m a.s.l.) and Venezuela (Merida, 4765 m a.s.l.). We report on detector calibration and operation at high altitude, search for bursts in 4 months of preliminary data, as well as search for signal at ground level when satellites report a burst

Use of water-Cherenkov detectors to detect Gamma Ray Bursts at the Large Aperture GRB Observatory (LAGO)

Energy Technology Data Exchange (ETDEWEB)

Allard, D. [APC, CNRS et Universite Paris 7 (France); Allekotte, I. [Centro Atomico Bariloche, Instituto Balseiro (Argentina); Alvarez, C. [Facultad de Ciencias Fisico-Matematicas de la BUAP (Mexico); Asorey, H. [Centro Atomico Bariloche, Instituto Balseiro (Argentina); Barros, H. [Laboratorio de Fisica Nuclear, Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of); Bertou, X. [Centro Atomico Bariloche, Instituto Balseiro (Argentina)], E-mail: bertou@cab.cnea.gov.ar; Burgoa, O. [Instituto de Investigaciones Fisicas, UMSA (Bolivia); Gomez Berisso, M. [Centro Atomico Bariloche, Instituto Balseiro (Argentina); Martinez, O. [Facultad de Ciencias Fisico-Matematicas de la BUAP (Mexico); Miranda Loza, P. [Instituto de Investigaciones Fisicas, UMSA (Bolivia); Murrieta, T.; Perez, G. [Facultad de Ciencias Fisico-Matematicas de la BUAP (Mexico); Rivera, H. [Instituto de Investigaciones Fisicas, UMSA (Bolivia); Rovero, A. [Instituto de Astronomia y Fisica del Espacio (Argentina); Saavedra, O. [Dipartimento di Fisica Generale and INFN, Torino (Italy); Salazar, H. [Facultad de Ciencias Fisico-Matematicas de la BUAP (Mexico); Tello, J.C. [Laboratorio de Fisica Nuclear, Universidad Simon Bolivar, Caracas (Venezuela, Bolivarian Republic of); Ticona Peralda, R.; Velarde, A. [Instituto de Investigaciones Fisicas, UMSA (Bolivia); Villasenor, L. [Facultad de Ciencias Fisico-Matematicas de la BUAP (Mexico); Instituto de Fisica y Matematicas, Universidad de Michoacan (Mexico)

2008-09-21

The Large Aperture GRB Observatory (LAGO) project aims at the detection of high energy photons from Gamma Ray Bursts (GRB) using the single particle technique in ground-based water-Cherenkov detectors (WCD). To reach a reasonable sensitivity, high altitude mountain sites have been selected in Mexico (Sierra Negra, 4550 m a.s.l.), Bolivia (Chacaltaya, 5300 m a.s.l.) and Venezuela (Merida, 4765 m a.s.l.). We report on detector calibration and operation at high altitude, search for bursts in 4 months of preliminary data, as well as search for signal at ground level when satellites report a burst.

40 CFR 144.7 - Identification of underground sources of drinking water and exempted aquifers.

Science.gov (United States)

2010-07-01

..., all aquifers or parts of aquifers which meet the definition of an “underground source of drinking... underground source of drinking water if it meets the definition in § 144.3. (b)(1) The Director may identify... mineral or hydrocarbon producing. Information contained in the mining plan for the proposed project, such...

Beam test of Cherenkov counter prototype for ZDF setup

International Nuclear Information System (INIS)

Kacharava, A.K.; Macharashvili, G.G.; Nioradze, M.S.; Komarov, V.I.; Sopov, V.S.; Chernyshev, V.P.

1995-01-01

We describe a Cherenkov counter of total internal reflection for particle separation in the momentum range where all types of particles radiate Cherenkov light. The Cherenkov counter prototype with the lucite radiator was tested on the secondary beam of the ITEP (Moscow) accelerator. Dependence of the photomultiplier pulse height on the particle entrance angle was clearly observed. 4 refs., 4 figs

Uranium in underground water public supply of the metropolitan region of Recife

International Nuclear Information System (INIS)

Silva, C.M.; Sousa, G.H.; Vasconcelos, W.E.; Hazin, C.A.; Amaral, R.S.

2001-01-01

The geologic formation of the metropolitan region of Recife is of sedimentary origin. In the coast area, where the phosphate deposits are located, it is sufficiently rich in underground hydric features. In the superposed layers of the sedimentary basin exists three underground aquifers and 80% of the underground hydric features of public supplying of the metropolitan region of Recife are located in the phosphate deposits, which are rich in uranium. Physiologically the uranian are in the steady state (6+) with bivalent cations U 2+ 2 . The ingestion of uranium by man occurs through foods and water ingestion. The places of the human body where it has greater clamping of this radionuclides are the bones. The uranium is deposited slowly from surface of the bone, redistributing itself in route to the marrow. An important competition between Ca 2+ 2 and the UO 2+ 2 exists in the kidneys, where the Ca 2+ 2 efficiently is absorbed. This work was carried through aiming to determine the concentrations of uranium in waters of the wells of public supplying of the metropolitan region of Recife, collating them with the limits established for the Health Department, that establishes the level of 0.1 Bq/L referring to the total alpha radioactivity in drinking waters

Underground waters and soil contamination studies

International Nuclear Information System (INIS)

Ferreira, Vinicius V.M.; Camargos, Claudio C.; Santos, Rosana A.M.

2009-01-01

Maybe the greatest problem associated to the nuclear energy is what to do with the waste generated. As example, in Portugal, two of the most important of uranium mines produced a significant amount of waste, now deposited in several storage facilities. To evaluate the impacts generated, samples of water, sediments and soils were analyzed. The space distribution of these samples revealed that the contamination is restricted in the vicinity of the mining areas, and the biggest problem happened due to the illegal use of waters for irrigation, originated from the mine effluents treatment stations. In Brazil, the radioactive waste remains a problem for the authorities and population, since there is not until now a final repository to storage them. The objective of this work is to do studies with the software FRAC3DVS, which simulates the contamination of soils and underground waters due to radioactive and no radioactive sources of pollution. The obtained results show that this tool can help in environmental evaluations and decision making processes in the site selection of a radioactive waste repository. (author)

PATTERNS UTILIZED IN THE SIMULATION OF UNDERGROUND WATER FLOW AND THE TRANSPORTATION OF POLLUTANTS IN THE BAHLUI DRAINAGE BASIN

Directory of Open Access Journals (Sweden)

Ionut Minea

2012-03-01

Full Text Available ABSTRACT. – Patterns utilized in the simulation of underground water flow and the transportation of pollutants in the Bahlui drainage basin. In the actual context of accelerate economic development, the excessive exploatation of water resources from the underground and the contamination of these with different water pollutants has become a major problem which has enetered the attention of many researchers. For the evaluation of an underground water flow and pollutants transport sistem we have chosen the package of programs MODFLOW which includes a whole series of applications,such as MOC3D, MT3D, MT3DMS, PEST, UCODE, PMPATH, which allow simulations and multiple recalibrations of the capacity of recharging of the aquifers, the flowing of the water towards wells and drillings the transport of a pollutant agent in the underground or the evaluation of the exchange of water between the hidrographic network and aquifers. The sistem targets both the evaluation of the modelation of the underground flowing and the simulation of a punctual polluation of the canvas of groundwater scenery, in the meadow of the river Bahlui, west from Letcani village.

Concentration of arsenic in underground and drinking water in Kostolac coal basin (northern-east Serbia, Yugoslavia)

International Nuclear Information System (INIS)

Panic, Lj.; Vlajkovic, M.

2002-01-01

Arsenic is a widespread element in nature. Increased amounts of arsenic in drinking water are appearing in regions and areas with intensive exploitation of coal ant it's combustion in thermoelectrical power plants (China, Taiwan). That is why we studied containment of arsenic in flood, drainage and underground waters from ash deposits of Kostolac thermoelectrical power plants, wells and local water system in Kostolac and four surrounding villages. Increased amounts of arsenic in ash (19-33 mg/kg), which is hydraulically transported from thermoelectrical power plants are causing contamination of underground waters under and near ash deposits (0.1-0.08 mg/l). However, increased amount of arsenic in those underground waters don't pollute wells for water supplying population with drinking water, because in these causes, amount's of arsenic found in examined areas are under 0.05 mg/l. We have concluded that despite increased amounts of arsenic in the ashes of thermoelectrical power plants, contamination of residents water supplying wells has not occurred for the last few decades, but the risk of that still exists. Therefore we suggest regular controls of arsenic containment in drinking water and further construction of regional water supply system. (author)

Underground coal mine subsidence impacts on surface water

International Nuclear Information System (INIS)

Stump, D.E. Jr.

1992-01-01

This paper reports that subsidence from underground coal mining alters surface water discharge and availability. The magnitude and areal extent of these impacts are dependent on many factors, including the amount of subsidence, topography, geology, climate, surface water - ground water interactions, and fractures in the overburden. There alterations may have positive and/or negative impacts. One of the most significant surface water impacts occurred in July 1957 near West Pittston, Pennsylvania. Subsidence in the Knox Mine under the Coxton Yards of the Lehigh Valley Railroad allowed part of the discharge in the Susquehanna River to flow into the mine and create a crater 200 feet in diameter and 300 feet deep. Fourteen railroad gondola cars fell into the hole which was eventually filled with rock, sand, and gravel. Other surface water impacts from subsidence may include the loss of water to the ground water system, the gaining of water from the ground water system, the creation of flooded subsidence troughs, the increasing of impoundment storage capacity, the relocation of water sources (springs), and the alteration of surface drainage patterns

Geostatistical Characteristic of Space -Time Variation in Underground Water Selected Quality Parameters in Klodzko Water Intake Area (SW Part of Poland)

Science.gov (United States)

Namysłowska-Wilczyńska, Barbara

2016-04-01

This paper presents selected results of research connected with the development of a (3D) geostatistical hydrogeochemical model of the Klodzko Drainage Basin, dedicated to the spatial and time variation in the selected quality parameters of underground water in the Klodzko water intake area (SW part of Poland). The research covers the period 2011÷2012. Spatial analyses of the variation in various quality parameters, i.e, contents of: ammonium ion [gNH4+/m3], NO3- (nitrate ion) [gNO3/m3], PO4-3 (phosphate ion) [gPO4-3/m3], total organic carbon C (TOC) [gC/m3], pH redox potential and temperature C [degrees], were carried out on the basis of the chemical determinations of the quality parameters of underground water samples taken from the wells in the water intake area. Spatial and time variation in the quality parameters was analyzed on the basis of archival data (period 1977÷1999) for 22 (pump and siphon) wells with a depth ranging from 9.5 to 38.0 m b.g.l., later data obtained (November 2011) from tests of water taken from 14 existing wells. The wells were built in the years 1954÷1998. The water abstraction depth (difference between the terrain elevation and the dynamic water table level) is ranged from 276÷286 m a.s.l., with an average of 282.05 m a.s.l. Dynamic water table level is contained between 6.22 m÷16.44 m b.g.l., with a mean value of 9.64 m b.g.l. The latest data (January 2012) acquired from 3 new piezometers, with a depth of 9÷10m, which were made in other locations in the relevant area. Thematic databases, containing original data on coordinates X, Y (latitude, longitude) and Z (terrain elevation and time - years) and on regionalized variables, i.e. the underground water quality parameters in the Klodzko water intake area determined for different analytical configurations (22 wells, 14 wells, 14 wells + 3 piezometers), were created. Both archival data (acquired in the years 1977÷1999) and the latest data (collected in 2011÷2012) were analyzed

Redevelopment drawing off of underground waters - a tool for lowering of environmental influences of the decommissioned A-1 NPP on the environment

International Nuclear Information System (INIS)

Kostolansky, M.; Benko, J.; Plsko, J.; Machyniak, P.

2003-01-01

Decommissioned A-1 NPP is the main source of radioactive contamination of the underground waters in the locality of nuclear energetic facilities in Jaslovske Bohunice. This situation is the consequence of historical as well as present leaks of the radioactive contamination into geological surroundings of the locality. The tritium is the determining radionuclide. The remedial measures were accepted for solution of this negative influence on the environment. The aim of these measures was the minimisation of influence of the underground waters. One of instruments, which supply the decreasing of environmental influence of the decommissioned A-1 NPP on underground waters, is the also redevelopment drawing off of underground waters. In this paper is briefly said the process of planning of the optimal technology and of the parameters of redevelopment drawing off of underground waters in the area of the A-1 NPP and its realisation. The main part of the paper is dedicated to the evaluation of results of realisation of the redevelopment drawing off of underground waters and to the total evaluation of this measure for assigning of protection of underground waters, their resources and right function of water divisions of this locality in the meaning of applicable legislation. (authors)

Looking inside volcanoes with the Imaging Atmospheric Cherenkov Telescopes

Science.gov (United States)

Del Santo, M.; Catalano, O.; Cusumano, G.; La Parola, V.; La Rosa, G.; Maccarone, M. C.; Mineo, T.; Sottile, G.; Carbone, D.; Zuccarello, L.; Pareschi, G.; Vercellone, S.

2017-12-01

Cherenkov light is emitted when charged particles travel through a dielectric medium with velocity higher than the speed of light in the medium. The ground-based Imaging Atmospheric Cherenkov Telescopes (IACT), dedicated to the very-high energy γ-ray Astrophysics, are based on the detection of the Cherenkov light produced by relativistic charged particles in a shower induced by TeV photons interacting with the Earth atmosphere. Usually, an IACT consists of a large segmented mirror which reflects the Cherenkov light onto an array of sensors, placed at the focal plane, equipped by fast electronics. Cherenkov light from muons is imaged by an IACT as a ring, when muon hits the mirror, or as an arc when the impact point is outside the mirror. The Cherenkov ring pattern contains information necessary to assess both direction and energy of the incident muon. Taking advantage of the muon detection capability of IACTs, we present a new application of the Cherenkov technique that can be used to perform the muon radiography of volcanoes. The quantitative understanding of the inner structure of a volcano is a key-point to monitor the stages of the volcano activity, to forecast the next eruptive style and, eventually, to mitigate volcanic hazards. Muon radiography shares the same principle as X-ray radiography: muons are attenuated by higher density regions inside the target so that, by measuring the differential attenuation of the muon flux along different directions, it is possible to determine the density distribution of the interior of a volcano. To date, muon imaging of volcanic structures has been mainly achieved with detectors made up of scintillator planes. The advantage of using Cherenkov telescopes is that they are negligibly affected by background noise and allow a consistently improved spatial resolution when compared to the majority of the current detectors.

Studies of runaway electrons via Cherenkov effect in tokamaks

Science.gov (United States)

Zebrowski, J.; Jakubowski, L.; Rabinski, M.; Sadowski, M. J.; Jakubowski, M. J.; Kwiatkowski, R.; Malinowski, K.; Mirowski, R.; Mlynar, J.; Ficker, O.; Weinzettl, V.; Causa, F.; COMPASS; FTU Teams

2018-01-01

The paper concerns measurements of runaway electrons (REs) which are generated during discharges in tokamaks. The control of REs is an important task in experimental studies within the ITER-physics program. The NCBJ team proposed to study REs by means of Cherenkov-type detectors several years ago. The Cherenkov radiation, induced by REs in appropriate radiators, makes it possible to identify fast electron beams and to determine their spatial- and temporal-characteristics. The results of recent experimental studies of REs, performed in two tokamaks - COMPASS in Prague and FTU in Frascati, are summarized and discussed in this paper. Examples of the electron-induced signals, as recorded at different experimental conditions and scenarios, are presented. Measurements performed with a three-channel Cherenkov-probe in COMPASS showed that the first fast electron peaks can be observed already during the current ramp-up phase. A strong dependence of RE-signals on the radial position of the Cherenkov probe was observed. The most distinct electron peaks were recorded during the plasma disruption. The Cherenkov signals confirmed the appearance of post-disruptive RE beams in circular-plasma discharges with massive Ar-puffing. During experiments at FTU a clear correlation between the Cherenkov detector signals and the rotation of magnetic islands was identified.

Application of Cherenkov light observation to reactor measurements (3). Evaluation of spent fuel elements of LWRs with Cherenkov light estimation system

International Nuclear Information System (INIS)

Yamamoto, Keiichi; Takeuchi, Tomoaki; Tsuchiya, Kunihiko; Hayashi, Takayasu; Kosuge, Fumiaki

2016-11-01

Development of the reactor measurement system has been carried out to obtain the real-time in-core nuclear and thermal information, where the quantitative measurement of brightness of Cherenkov light was investigated. The system would be applied as a monitoring system in severe accidents and for the advanced operation management technology in existing LWRs. This report summarized the modification of Cherenkov light estimation system described JAEA-Testing 2015-001 and the result of the burn-up evaluation by Cherenkov light image emitted from spent fuel elements of LWRs with the modified system. (author)

Evaluation of the effects of underground water usage and spillage in the Exploratory Studies Facility

International Nuclear Information System (INIS)

Dunn, E.; Sobolik, S.R.

1993-12-01

The Yucca Mountain Site Characterization Project is studying Yucca Mountain in southwestern Nevada as a potential site for a high-level radioactive waste repository. Analyses reported herein were performed to support the design of site characterization activities so that these activities will have a minimal impact on the ability of the site to isolate waste and a minimal impact on underground tests performed as part of the characterization process. These analyses examine the effect of water to be used in the underground construction and testing activities for the Exploratory Studies Facility on in situ conditions. Underground activities and events where water will be used include construction, expected but unplanned spills, and fire protection. The models used predict that, if the current requirements in the Exploratory Studies Facility Design Requirements are observed, water that is imbibed into the tunnel wall rock in the Topopah Springs welded tuff can be removed over the preclosure time period by routine or corrective ventilation, and also that water imbibed into the Paintbrush Tuff nonwelded tuff will not reach the potential waste storage area

Design of on-line steam generator leak monitoring system based on Cherenkov counting technique

International Nuclear Information System (INIS)

Dileep, B.N.; D'Cruz, S.J.; Biju, P.; Jashi, K.B.; Prabhakaran, V.; Venkataramana, K.; Managanvi, S.S.

2006-01-01

The methodology developed by Nuclear Power Corporation of India Ltd. for identification of leaky Steam Generator (SG) by monitoring 134 I activity in the blow down water is a very high sensitive method. However, this technique can not be put into use as an on-line system. A new method of on-line detection of SG leak and identify the offending SG based on Cherenkov counting technique is explained in this paper. It identifies the leak by detecting Cherenkov radiation produced by the hard beta emitting radio nuclides escaped into feed water during leak in an operating reactor. A simulated system shows that a leak rate of 2 kg/h can be detected by the proposed system, while coolant 134 I activity is 3.7 MBq/l (100μCi/l). (author)

Assessment of underground water potential zones using modern geomatics technologies in Jhansi district, Uttar Pradesh, India.

Science.gov (United States)

Pandey, N. K.; Shukla, A. K.; Shukla, S.; Pandey, M.

2014-11-01

Ground water is a distinguished component of the hydrologic cycle. Surface water storage and ground water withdrawal are traditional engineering approaches which will continue to be followed in the future. The uncertainty about the occurrence, distribution and quality aspect of the ground water and the energy requirement for its withdrawal impose restriction on exploitation of ground water. The main objective of the study is assessment of underground water potential zones of Jhansi city and surrounding area, by preparing underground water potential zone map using Geographical Information System (GIS), remote sensing, and validation by underground water inventory mapping using GPS field survey done along the parts of National Highway 25 and 26 and some state highway passing through the study area. Study area covers an area of 1401 km2 and its perimeter is approximate 425 km. For this study Landsat TM (0.76-0.90 um) band data were acquired from GLCF website. Sensor spatial resolution is 30 m. Satellite image has become a standard tool aiding in the study of underground water. Extraction of different thematic layers like Land Use Land Cover (LULC), settlement, etc. can be done through unsupervised classification. The modern geometics technologies viz. remote sensing and GIS are used to produce the map that classifies the groundwater potential zone to a number of qualitative zone such as very high, high, moderate, low or very low. Thematic maps are prepared by visual interpretation of Survey of India topo-sheets and linearly enhanced Landsat TM satellite image on 1 : 50,000 scale using AutoCAD, ArcGIS 10.1 and ERDAS 11 software packages.

Cherenkov and scintillation light separation in organic liquid scintillators

Energy Technology Data Exchange (ETDEWEB)

Caravaca, J.; Descamps, F.B.; Land, B.J.; Orebi Gann, G.D. [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Yeh, M. [Brookhaven National Laboratory, Upton, NY (United States)

2017-12-15

The CHErenkov/Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2 g/L of PPO as a fluor (LAB/PPO). This is the first successful demonstration of Cherenkov light detection from the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338 ± 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 ± 3% and 63 ± 8% for time- and charge-based separation, respectively, with scintillation contamination of 36 ± 5% and 38 ± 4. LAB/PPO data is consistent with a rise time of τ{sub r} = 0.72 ± 0.33 ns. (orig.)

Cherenkov and scintillation light separation in organic liquid scintillators

International Nuclear Information System (INIS)

Caravaca, J.; Descamps, F.B.; Land, B.J.; Orebi Gann, G.D.; Yeh, M.

2017-01-01

The CHErenkov/Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2 g/L of PPO as a fluor (LAB/PPO). This is the first successful demonstration of Cherenkov light detection from the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338 ± 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 ± 3% and 63 ± 8% for time- and charge-based separation, respectively, with scintillation contamination of 36 ± 5% and 38 ± 4. LAB/PPO data is consistent with a rise time of τ r = 0.72 ± 0.33 ns. (orig.)

Uptake of uranium from underground drinking water by chlorella (Chlorella pyrendoidosa)

International Nuclear Information System (INIS)

Singhal, R.K.; Joshi, Shobha; Gurg, R.P.; Shenoy, N.S.; Ferandes, Neychelle; Gopale, Rajesh S.; Jhaveri, A.S.

2002-01-01

Naturally occurring uranium has found at elevated levels i.e. 300-1200 ppb in underground water, especially in the areas located around uranium mines and granite rocks sites. The U.S. Environmental Protection Agency (EPA) recently adopted drinking water standards requiring a maximum uranium concentration of 20 μgl. This limit is based on nephro-toxicity, rather than on radiological hazards. The concentration of uranium is to be monitored along with other parameters in well and other sources of drinking water in these areas. During this work a low cost kit was developed for removing uranium from under-ground water used for drinking purposes. This unit is capable of reducing uranium from 1000 ppb to 15-20 ppb. Chlorella (Chlorella pyrendoidosa), a fresh water algae, was immobilised in sodium alginate in the form of beads by using 0.2 M calcium chloride. These beads were put in container and the water is stirred occasionally. 99-100 % uranium adsorbed was recovered from the beads by using 0.1 M HNO 3 . These results suggest that the uptake of uranium by Chlorella depended upon the physico-chemical adsorption on the cell surface, but not upon the biological activity and that uranium in the algal cells was coupled with the ligands, which can be easily substituted with NO 3 -1 . (author)

Cherenkov TOF PET with silicon photomultipliers

Science.gov (United States)

Dolenec, R.; Korpar, S.; Križan, P.; Pestotnik, R.

2015-12-01

As previously demonstrated, an excellent timing resolution below 100 ps FWHM is possible in time-of-flight positron emission tomography (TOF PET) if the detection method is based on the principle of detecting photons of Cherenkov light, produced in a suitable material and detected by microchannel plate photomultipliers (MCP PMTs). In this work, the silicon photomultipliers (SiPMs) were tested for the first time as the photodetectors in Cherenkov TOF PET. The high photon detection efficiency (PDE) of SiPMs led to a large improvement in detection efficiency. On the other hand, the time response of currently available SiPMs is not as good as that of MCP PMTs. The SiPM dark counts introduce a new source of random coincidences in Cherenkov method, which would be overwhelming with present SiPM technology at room temperature. When the apparatus was cooled, its performance significantly improved.

''In sutu'' radiation cleaning of underground water contaminated with cyanides - six years of experience

International Nuclear Information System (INIS)

Pastuszek, F.; Vacek, K.; Vondruska, V.

1993-01-01

Underground water, contaminated with cyanides, has been successfully cleaned using the hydraulic barrier method (assembly of pumped wells) since 1986. The average cyanide concentrations in the outflow exceeded 35 mg per litre. Contamination had to be eliminated before the discharge into the sewer system. The radiation approach ''in situ'' i.e. decomposition of cyanides by barrier, was applied and is still being used today. The cyanide concentration was lowered more than one order of magnitude. This process was approved by the Czechoslovak radiation security authorities and further applications of ''in situ'' regeneration of underground water contamination is anticipated. (author)

Development of a research reactor power measurement system using Cherenkov radiation

Energy Technology Data Exchange (ETDEWEB)

Salles, Brício M.; Mesquita, Amir Z., E-mail: briciomares@hotmail.com, E-mail: amir@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-11-01

Nuclear research reactors are usually located in open pools, to allow visibility to the core and bluish luminosity of Cherenkov radiation. Usually the thermal power released in these reactors is monitored by chambers that measure the neutron flux, as it is proportional to the power. There are other methods used for power measurement, such as monitoring the core temperature and the energy balance in the heat exchanger. The brightness of Cherenkov's radiation is caused by the emission of visible electromagnetic radiation (in the blue band) by charged particles that pass through an insulating medium (water in nuclear research reactors) at a speed higher than that of light in this medium. This effect was characterized by Pavel Cherenkov, which earned him the Nobel Prize for Physics in 1958. The project's objective is to develop an innovative and alternative method for monitoring the power of nuclear research reactors. It will be performed by analyzing and monitoring the intensity of luminosity generated by Cherenkov radiation in the reactor core. This method will be valid for powers up to 250 kW, since above that value the luminosity saturates, as determined by previous studies. The reactor that will be used to test the method is the TRIGA, located at Nuclear Technology Development Center (CDTN), which currently has a maximum operating power of 250 kW. This project complies with International Atomic Energy Agency (IAEA) recommendations on reactor safety. It will give more redundancy and diversification in this measure and will not interfere with its operation. (author)

Development of a research reactor power measurement system using Cherenkov radiation

International Nuclear Information System (INIS)

Salles, Brício M.; Mesquita, Amir Z.

2017-01-01

Nuclear research reactors are usually located in open pools, to allow visibility to the core and bluish luminosity of Cherenkov radiation. Usually the thermal power released in these reactors is monitored by chambers that measure the neutron flux, as it is proportional to the power. There are other methods used for power measurement, such as monitoring the core temperature and the energy balance in the heat exchanger. The brightness of Cherenkov's radiation is caused by the emission of visible electromagnetic radiation (in the blue band) by charged particles that pass through an insulating medium (water in nuclear research reactors) at a speed higher than that of light in this medium. This effect was characterized by Pavel Cherenkov, which earned him the Nobel Prize for Physics in 1958. The project's objective is to develop an innovative and alternative method for monitoring the power of nuclear research reactors. It will be performed by analyzing and monitoring the intensity of luminosity generated by Cherenkov radiation in the reactor core. This method will be valid for powers up to 250 kW, since above that value the luminosity saturates, as determined by previous studies. The reactor that will be used to test the method is the TRIGA, located at Nuclear Technology Development Center (CDTN), which currently has a maximum operating power of 250 kW. This project complies with International Atomic Energy Agency (IAEA) recommendations on reactor safety. It will give more redundancy and diversification in this measure and will not interfere with its operation. (author)

Prospects for very large, sensitive water Cherenkov detectors for proton decay and neutrino oscillations search

International Nuclear Information System (INIS)

Cline, D.B.

1982-01-01

We discuss the possibility of constructing large water Cherenkov detectors with mass 10 5 to 10 6 tons that would be sensitive to a few hundred MeV - few GeV energy release. The 10 5 ton detector would be suitable for a search for certain proton decay modes whereas the 10 6 ton detector would act as an active shield for the proton decay detector and as a nu/sub e/, nu/sub μ/ and possibly nu/sub tau/ interaction detector. The neutrino physics would include a sensitive search for neutrino oscillations using atmospheric neutrinos. The location of this detector could be in the deep ocean near Hawaii or in a deep trench between Cuba and Haiti or perhaps deep lakes like Superior or Baikal if flexible containers are used

Vavilov-Cherenkov and Synchrotron Radiation Foundations and Applications

CERN Document Server

Afanasiev, G. N

2005-01-01

The theory of the Vavilov-Cherenkov radiation observed by Cherenkov in 1934 was created by Tamm, Frank and Ginsburg who associated the observed blue light with the uniform charge motion of a charge at a velocity greater than the velocity of light in the medium. On the other hand, Vavilov, Cherenkov's teacher, attributed the observed blue light to the deceleration of electrons. This has given rise to the appearance of papers in which the radiation of a charge uniformly moving in a finite space interval was related to the Bremsstrahlung arising at the end points of the motion interval. This monograph is intended for students of the third year and higher, for postgraduates, for professional scientists (both experimentalists and theoreticians) dealing with Vavilov-Cherenkov and synchrotron radiation. An acquaintance with the three volumes of the Landau and Lifshitz course (Quantum Mechanics, Classical Field Theory and Macroscopic Electrodynamics) is sufficient for understanding the text.

Generation and propagation of synchro - Cherenkov radiation

International Nuclear Information System (INIS)

Heintzmann, H.; Novello, M.; Schruefer, E.

1981-01-01

Particles moving along the magnetic field lines emit under favorable conditions Cherenkov radiation in a cold, rarefied plasma. A peculiar phenomenon occurs for curved magnetic fields: in for example a toroidal magnetic field the radiation spirals inward and approaches a resonance. Both the generation and the study of the propagation of these Cherenkov modes appear to be within reach of present technology. (Author) [pt

Upscaling laboratory results for water quality prediction at underground collieries in South Africa's Highveld Coalfields

Energy Technology Data Exchange (ETDEWEB)

Usher, B.H. [University of Orange Free State, Bloemfontein (South Africa). Institute for Groundwater Studies

2009-01-15

The prediction of future acidity and water quality is a key aspect of water management in mining environments. In this paper, different prediction techniques tested in an isolated underground compartment at a colliery in the Highveld Coalfield of South Africa are discussed. Considerations for upscaling these results are explained, and a methodology for upscaling is tested at this facility. Over 30 samples were collected around the compartment and through cored boreholes. These samples were tested using acid-base accounting tests, humidity cells, and mineralogy. From this, an integrated interpretation of potential water quality evolution was made, supported by detailed water quality sampling with the use of surface boreholes, stratified sampling underground, and pumped qualities over a period of two years. The results show that analytical tests play an integral role in water quality predictions at underground collieries. The results also show that, despite the vast differences between laboratory test conditions and the situation in the field, by taking site conditions into account to properly contextualise the results, improved predictions of expected water quality can be obtained.

Muon imaging of volcanoes with Cherenkov telescopes

Science.gov (United States)

Carbone, Daniele; Catalano, Osvaldo; Cusumano, Giancarlo; Del Santo, Melania; La Parola, Valentina; La Rosa, Giovanni; Maccarone, Maria Concetta; Mineo, Teresa; Pareschi, Giovanni; Sottile, Giuseppe; Zuccarello, Luciano

2017-04-01

The quantitative understanding of the inner structure of a volcano is a key feature to model the processes leading to paroxysmal activity and, hence, to mitigate volcanic hazards. To pursue this aim, different geophysical techniques are utilized, that are sensitive to different properties of the rocks (elastic, electrical, density). In most cases, these techniques do not allow to achieve the spatial resolution needed to characterize the shallowest part of the plumbing system and may require dense measurements in active zones, implying a high level of risk. Volcano imaging through cosmic-ray muons is a promising technique that allows to overcome the above shortcomings. Muons constantly bombard the Earth's surface and can travel through large thicknesses of rock, with an energy loss depending on the amount of crossed matter. By measuring the absorption of muons through a solid body, one can deduce the density distribution inside the target. To date, muon imaging of volcanic structures has been mainly achieved with scintillation detectors. They are sensitive to noise sourced from (i) the accidental coincidence of vertical EM shower particles, (ii) the fake tracks initiated from horizontal high-energy electrons and low-energy muons (not crossing the target) and (iii) the flux of upward going muons. A possible alternative to scintillation detectors is given by Cherenkov telescopes. They exploit the Cherenkov light emitted when charged particles (like muons) travel through a dielectric medium, with velocity higher than the speed of light. Cherenkov detectors are not significantly affected by the above noise sources. Furthermore, contrarily to scintillator-based detectors, Cherenkov telescopes permit a measurement of the energy spectrum of the incident muon flux at the installation site, an issue that is indeed relevant for deducing the density distribution inside the target. In 2014, a prototype Cherenkov telescope was installed at the Astrophysical Observatory of Serra

Modern radionuclide content of the underground water and soils near the epicentral zone of cratering explosion at the Semipalatinsk test site

International Nuclear Information System (INIS)

Gordeev, S.K.; Kvasnikova, E.V.

2004-01-01

The investigation wells for a control of the underground water contamination were bored after the cratering explosions at the Semipalatinsk Test Site, now they are restored partially. The analysis of the retrospective information of the Institute of Global Climate and Ecology (Moscow, Russia) give a possibility to choose wells and terrains for the successful study of radionuclide migration with the underground water. The epicentral zone, the crater and the territory with radius 1,5 km around the underground cratering explosion '1003' were investigated under the ISTC project K-810. Underground water and soil samples were taken at the two expeditions of 2003. The chemical extraction methods taking into account the water mineral composition, gamma-spectrum methods, methods of the liquid scintillation spectrometry and methods of alpha-spectrometry were used. The modern radionuclide content ( 3 H, 90 Sr, 137 Cs, 239+240 Pu, 241 Am) of the underground water will be presented and compare with a radionuclide content of soils around crater. The retrospective information will be added by these modern data. The vertical radionuclide distribution in soils will be presented. (author)

Countermeasures planned for reducing water inflow into deep shafts at the Mizunami Underground Research Laboratory. Research for post-excavation grouting

International Nuclear Information System (INIS)

Kuji, Masayoshi; Matsui, Hiroya; Hara, Masato; Mikake, Shinichiro; Takeuchi, Shinji; Asai, Hideaki; Minamide, Masashi; Sato, Toshinori

2009-01-01

A large amount of water inflow is frequently occurs during the excavation of an underground cavern, such as road and railway tunnels, and underground electric facilities etc. The reduction of water inflow is sometimes quite important for the cost reduction for the water treatment and pumping during the construction of an underground cavern. The Mizunami Underground Research Laboratory (MIU) is currently being constructed by Japan Atomic Energy Agency. During its excavation, a large amount of water inflow into the shafts has been increasing and affecting the project progress. Therefore, a field experiment of post-excavation grouting around the Ventilation Shaft in a sedimentary formation carried out to confirm the effect of existing grouting technology for sedimentary formations in MIU project. The result shows that the applied methods in this field experiment are effective to prevent water inflow. This report describes the summary of the field experiment and the knowledge obtained through the experiment. (author)

Development of a SiPM Camera for a Schwarzschild-Couder Cherenkov Telescope for the Cherenkov Telescope Array

CERN Document Server

Otte, A N; Dickinson, H.; Funk, S.; Jogler, T.; Johnson, C.A.; Karn, P.; Meagher, K.; Naoya, H.; Nguyen, T.; Okumura, A.; Santander, M.; Sapozhnikov, L.; Stier, A.; Tajima, H.; Tibaldo, L.; Vandenbroucke, J.; Wakely, S.; Weinstein, A.; Williams, D.A.

2015-01-01

We present the development of a novel 11328 pixel silicon photomultiplier (SiPM) camera for use with a ground-based Cherenkov telescope with Schwarzschild-Couder optics as a possible medium-sized telescope for the Cherenkov Telescope Array (CTA). The finely pixelated camera samples air-shower images with more than twice the optical resolution of cameras that are used in current Cherenkov telescopes. Advantages of the higher resolution will be a better event reconstruction yielding improved background suppression and angular resolution of the reconstructed gamma-ray events, which is crucial in morphology studies of, for example, Galactic particle accelerators and the search for gamma-ray halos around extragalactic sources. Packing such a large number of pixels into an area of only half a square meter and having a fast readout directly attached to the back of the sensors is a challenging task. For the prototype camera development, SiPMs from Hamamatsu with through silicon via (TSV) technology are used. We give ...

Low-Noise Operation of All-Fiber Femtosecond Cherenkov Laser

DEFF Research Database (Denmark)

Liu, Xiaomin; Villanueva Ibáñez, Guillermo Eduardo; Lægsgaard, Jesper

2013-01-01

We investigate the noise properties of a femtosecond all-fiber Cherenkov radiation source with emission wavelength around 600 nm, based on an Yb-fiber laser and a highly-nonlinear photonic crystal fiber. A relative intensity noise as low as - 103 dBc/Hz, corresponding to 2.48 % pulse-to-pulse...... fluctuation in energy, was observed at the Cherenkov radiation output power of 4.3 mW, or 150 pJ pulse energy. This pulse-to-pulse fluctuation is at least 10.6 dB lower compared to spectrally-sliced supercontinuum sources traditionally used for ultrafast fiberbased generation at visible wavelengths. Low noise...... makes allfiber Cherenkov sources promising for biophotonics applications such as multi-photon microscopy, where minimum pulse-to-pulse energy fluctuation is required. We present the dependency of the noise figure on both the Cherenkov radiation output power and its spectrum....

Hydrogeology, water chemistry, and subsidence of underground coal mines at Huntsville, Missouri, July 1987 to December 1988. Water Resources Investigation

International Nuclear Information System (INIS)

Blevins, D.W.; Ziegler, A.C.

1992-01-01

Underground coal mining in and near Huntsville, in Randolph County in north-central Missouri, began soon after 1831. Mining in the Huntsville area was at its peak during 1903 and continued until 1966 when the last underground mine was closed and the economically recoverable coals under Huntsville had been mostly, if not completely, removed. The now abandoned mines are of concern to the public and to various State and Federal agencies for two reasons: (1) mine drainage acidifies streams and leaves large, soft, dangerous deposits of iron oxyhydroxides at mine springs and on streambeds (data on file at the Missouri Department of Natural Resources, Land Reclamation Commission), and (2) collapse of mine cavities sometimes causes surface subsidence resulting in property damage or personal injury. To address these concerns, the U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, in 1987 initiated a study to: determine the location of mine springs, the seasonal variation of stream-water chemistry, and the effects of underground-mine water on flow and water quality of nearby ground water and receiving streams; and identify areas susceptible to surface subsidence because of mine collapse. The purpose of the report is to present the findings and data collected for the study

Restoration of parameters of high-energy cascades in Cherenkov water calorimeter with a dense array of quasispherical modules

International Nuclear Information System (INIS)

Khomyakov, V. A.; Bogdanov, A. G.; Kindin, V. V.; Kokoulin, R. P.; Petrukhin, A. A.; Khokhlov, S. S.; Shutenko, V. V.; Yashin, I. I.

2015-01-01

A problem concerning the restoration of the parameters of a cascade shower with an unknown axis originating by muons in a Cherenkov water calorimeter is considered. A method for estimating the direction and geometric position of the cascade’s axis, which is based on the analysis of responses of quasispherical modules, and the criteria of selection of the events with cascades among the events with a large energy liberation are proposed. The method and the criteria are tested on events with cascades generated by near-horizontal muons of high energies detected by a DECOR coordinate-track detector. The preliminary results of measurements of the energy spectrum of cascade showers are presented

Hydrogeochemistry and Isotopic Study of the Origin of Underground Mine Water at Golden Star Bogoso/Prestea Limited (New Century Mines)

International Nuclear Information System (INIS)

Innosah, Gibrilla

2014-07-01

Hydrogeochemical study of the origin of underground mine water at Golden Star Bogoso/ Prestea Limited (New Century Mines) was carried out to determine the geochemical processes controlling surface water, groundwater and underground mine water and to identify the source of recharge to the underground water in the mines; investigate the hydrochemical facies of groundwater in the various aquifers (gallaries), and identify the relationship between surface water and groundwater, and underground mine water using hydrogeochemistry and stable isotope technique. Water from seventeen (17) surface water bodies, ten (10) hand-dug wells, eleven (11) boreholes and twenty-one (21) underground mine water samples were collected within Prestea in the Prestea-Huni Valley district of Western Region of Ghana between October 2013 and March 2014.The objectives of the study was achieved through the determination of pH, temperature, TDS, salinity, alkalinity, electrical conductivity, anions (SO_4"2-, HCO_3"-, Cl"-, PO_4"3"-, NO_3"-), major cations (Ca"2"+, Mg"2"+, Na"+, K"+) and trace elements (As, Cd, Cu, Fe, Mn, Pb and Zn). Arsenic,(As), was determined by Hydride Generation Atomic Absorption Spectrometry (HG-AAS). Levels of Cd, Cu, Fe, Mn, Mg, Pb and Zn were determined by Flame Atomic Absorption Spectrometry (FASS). The contents of Na"+ and K"+ were determined by Flame Photometry. Measurement of the levels of SO_4"2"-, PO_4"3"- and NO_3"- were achieved by UV-Visible spectrophotometry. Titrimetry was used for the determination of alkalinity, HCO_3"- and Cl"-. Temperature, pH, Conductivity, Salinity and Total Dissolved Solids (TDS) of the surface water, groundwater and underground mine water were all assessed. The stable isotopes (δ"2H and δ"1"8O) compositions of the waters were determined using the Liquid-Water Isotope Analyzer [based on Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) via laser absorption]. The determined Levels of major cations (in ranges, meq/L) for the

UNDERGROUND

Energy Technology Data Exchange (ETDEWEB)

Anon.

1993-11-15

Full text: Cossetted deep underground, sheltered from cosmic ray noise, has always been a favourite haunt of neutrino physicists. Already in the 1930s, significant limits were obtained by taking a geiger counter down in Holborn 'tube' station, one of the deepest in London's underground system. Since then, neutrino physicists have popped up in many unlikely places - gold mines, salt mines, and road tunnels deep under mountain chains. Two such locations - the 1MB (Irvine/ Michigan/Brookhaven) detector 600 metres below ground in an Ohio salt mine, and the Kamiokande apparatus 1000m underground 300 km west of Tokyo - picked up neutrinos on 23 February 1987 from the famous 1987A supernova. Purpose-built underground laboratories have made life easier, notably the Italian Gran Sasso Laboratory near Rome, 1.4 kilometres below the surface, and the Russian Baksan Neutrino Observatory under Mount Andyrchi in the Caucasus range. Gran Sasso houses ICARUS (April, page 15), Gallex, Borexino, Macro and the LVD Large Volume Detector, while Baksan is the home of the SAGE gallium-based solar neutrino experiment. Elsewhere, important ongoing underground neutrino experiments include Soudan II in the US (April, page 16), the Canadian Sudbury Neutrino Observatory with its heavy water target (January 1990, page 23), and Superkamiokande in Japan (May 1991, page 8)

CLASSiC: Cherenkov light detection with silicon carbide

Energy Technology Data Exchange (ETDEWEB)

Adriani, Oscar [Physics Dept., University of Florence, Via Sansone 1, 50019, Sesto Fiorentino (Italy); INFN dep. of Florence, Via Bruno Rossi 1, 50019 Sesto Fiorentino (Italy); Albergo, Sebastiano [Physics Dept., University of Catania, Via Santa Sofia 64, 95123 Catania (Italy); INFN dep. of Catania, Via Santa Sofia 64, 95123 Catania (Italy); D' Alessandro, Raffaello [Physics Dept., University of Florence, Via Sansone 1, 50019, Sesto Fiorentino (Italy); INFN dep. of Florence, Via Bruno Rossi 1, 50019 Sesto Fiorentino (Italy); Lenzi, Piergiulio [INFN dep. of Florence, Via Bruno Rossi 1, 50019 Sesto Fiorentino (Italy); Sciuto, Antonella [CNR-IMM, VIII Strada 5, Zona Industriale, Catania (Italy); INFN dep. of Catania, Via Santa Sofia 64, 95123 Catania (Italy); Starodubtsev, Oleksandr [INFN dep. of Florence, Via Bruno Rossi 1, 50019 Sesto Fiorentino (Italy); Tricomi, Alessia [Physics Dept., University of Catania, Via Santa Sofia 64, 95123 Catania (Italy); INFN dep. of Catania, Via Santa Sofia 64, 95123 Catania (Italy)

2017-02-11

We present the CLASSiC R&D for the development of a silicon carbide (SiC) based avalanche photodiode for the detection of Cherenkov light. SiC is a wide-bandgap semiconductor material, which can be used to make photodetectors that are insensitive to visible light. A SiC based light detection device has a peak sensitivity in the deep UV, making it ideal for Cherenkov light. Moreover, the visible blindness allows such a device to disentangle Cherenkov light and scintillation light in all those materials that scintillate above 400 nm. Within CLASSiC, we aim at developing a device with single photon sensitivity, having in mind two main applications. One is the use of the SiC APD in a new generation ToF PET scanner concept, using the Cherenov light emitted by the electrons following 511 keV gamma ray absorption as a time-stamp. Cherenkov is intrinsically faster than scintillation and could provide an unprecedentedly precise time-stamp. The second application concerns the use of SiC APD in a dual readout crystal based hadronic calorimeter, where the Cherenkov component is used to measure the electromagnetic fraction on an event by event basis. We will report on our progress towards the realization of the SiC APD devices, the strategies that are being pursued toward the realization of these devices and the preliminary results on prototypes in terms of spectral response, quantum efficiency, noise figures and multiplication.

Modern radionuclide content of the underground water and soils near the epicentral zone of cratering explosion at the Semipalatinsk test site

Energy Technology Data Exchange (ETDEWEB)

Gordeev, S.K.; Kvasnikova, E.V. [Institute of Global Climate and Ecology, Moscow (Russian Federation)

2004-07-01

The investigation wells for a control of the underground water contamination were bored after the cratering explosions at the Semipalatinsk Test Site, now they are restored partially. The analysis of the retrospective information of the Institute of Global Climate and Ecology (Moscow, Russia) give a possibility to choose wells and terrains for the successful study of radionuclide migration with the underground water. The epicentral zone, the crater and the territory with radius 1,5 km around the underground cratering explosion '1003' were investigated under the ISTC project K-810. Underground water and soil samples were taken at the two expeditions of 2003. The chemical extraction methods taking into account the water mineral composition, gamma-spectrum methods, methods of the liquid scintillation spectrometry and methods of alpha-spectrometry were used. The modern radionuclide content ({sup 3}H, {sup 90}Sr, {sup 137}Cs, {sup 239+240}Pu, {sup 241}Am) of the underground water will be presented and compare with a radionuclide content of soils around crater. The retrospective information will be added by these modern data. The vertical radionuclide distribution in soils will be presented. (author)

Simulation study of a hydrostat design for detecting underground leakage of water supply using neutron backscattering

International Nuclear Information System (INIS)

Kurosawa, Tadahiro; Nakamura, Takashi; Suzuki, Takashi; Okano, Yasuhiro; Chisaka, Haruo

1998-01-01

We have embarked upon the development of a new detection method for underground water leakage using a neutron backscattering system. We have estimated the performance capabilities of such a system using Monte Carlo simulation. It is indicated that a leak which results in 40% water content in the surrounding soils could be detected at depths of up to 40 cm from the surface to the center of the source of leakage. This new detection system could be useful as a hydrostat of underground water supply in noisy areas such as Tokyo, in place of presently-used hydrostats which are based on detection of changes in sound

Quenching the scintillation in CF4 Cherenkov gas radiator

International Nuclear Information System (INIS)

Blake, T.; D'Ambrosio, C.; Easo, S.; Eisenhardt, S.; Fitzpatrick, C.; Forty, R.; Frei, C.; Gibson, V.; Gys, T.; Harnew, N.; Hunt, P.; Jones, C.R.; Lambert, R.W.; Matteuzzi, C.; Muheim, F.; Papanestis, A.; Perego, D.L.; Piedigrossi, D.; Plackett, R.; Powell, A.

2015-01-01

CF 4 is used as a Cherenkov gas radiator in one of the Ring Imaging Cherenkov detectors at the LHCb experiment at the CERN Large Hadron Collider. CF 4 is well known to have a high scintillation photon yield in the near and far VUV, UV and in the visible wavelength range. A large flux of scintillation photons in our photon detection acceptance between 200 and 800 nm could compromise the particle identification efficiency. We will show that this scintillation photon emission system can be effectively quenched, consistent with radiationless transitions, with no significant impact on the photons resulting from Cherenkov radiation

In situ, high sensitivity, measurement of sup 9 sup 0 strontium in ground water using Cherenkov light

CERN Document Server

Bowyer, T W; Hossbach, T W; Hansen, R; Wilcox, W A

2000-01-01

The measurement of sup 9 sup 0 Sr in soils and ground water is important for characterization and remediation of radioactively contaminated sites. Measuring the sup 9 sup 0 Sr content to a few pCi/g of soil has been accomplished based on a design of scintillating fibers in a multilayered configuration measuring the high-energy beta emitted from sup 9 sup 0 Y decay (when in secular equilibrium with sup 9 sup 0 Sr), but has not been applied to water because the technique is sensitive to only the first few mm of soil. The volume of the source to which the detector is sensitive limits the theoretical sensitivity of such a detector, unless chemical preprocessing to strip the sup 9 sup 0 Sr from the water is performed. sup 9 sup 0 Sr activity in water can be quantified by detecting the high-energy beta particle by the Cherenkov light it produces when the high-energy beta from sup 9 sup 0 Y passes through the medium. We have used this phenomenon to sensitively measure sup 9 sup 0 Sr ( sup 9 sup 0 Y) from a volume of...

The Cherenkov Surface Detector of the Pierre Auger Observatory

Science.gov (United States)

Billoir, Pierre

2014-12-01

The Pierre Auger Observatory detects the atmospheric showers induced by cosmic rays of ultra-high energy (UHE). It is the first one to use the hybrid technique. A set of telescopes observes the fluorescence of the nitrogen molecules on clear moonless nights, giving access to the longitudinal profile of the shower. These telescopes surround a giant array of 1600 water Cherenkov tanks (covering more than 3000 km2), which works continuously and samples the particles reaching the ground (mainly muons, photons and electrons/positrons); the light produced within the water is recorded into FADC (Fast Analog to Digital Convertes) traces. A subsample of hybrid events provides a cross calibration of the two components. We describe the structure of the Cherenkov detectors, their sensitivity to different particles and the information they can give on the direction of origin, the energy and the nature of the primary UHE object; we discuss also their discrimination power for rare events (UHE photons or neutrinos). To cope with the variability of weather conditions and the limitations of the communication system, the procedures for trigger and real time calibration have been shared between local processors and a central acquisition system. The overall system has been working almost continuously for 10 years, while being progressively completed and increased by the creation of a dense "infill" subarray.

Assessment of Underground Water Contamination and Effect of Textile Effluents on Noyyal River Basin In and Around Tiruppur Town, Tamilnadu

Directory of Open Access Journals (Sweden)

A. Geetha

2008-01-01

Full Text Available A systematic study has been carried out to assess the underground water contamination and the effect of textile effluents on Noyyal River basin in and around Tiruppur Town. Twenty six sampling locations were selected at random and the ground water samples were collected mostly from tube wells at Noyyal River basin in and around Tiruppur area. The samples were analyzed for major physical and chemical water quality parameters like pH, alkalinity, electrical conductivity (EC, total dissolved solids (TDS, total hardness (TH, Ca, Mg, Na, K, Cl & SO42-. It was found that the underground water quality was contaminated at few sampling sites due to the industrial discharge of the effluents on to the river or land from the Tiruppur town. The sampling sites namely Orathupalayam, Karuvapalayam, Kulathupalayam, Uttukuli and Kodumanalpudur showed high deviations in total alkalinity, total hardness, Ca, Mg and chloride concentrations. Hence our study concludes that the underground water quality study in this region shows a constant variation in different parameters in different periods (before and after monsoon. So it is highly important to take periodical monitoring of the underground water quality in this region for our future sustainability

Context of surveillance of underground and surface waters; Contexte de la surveillance des eaux souterraines et superficielles

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

This document briefly describes the evolutions of regulations on site liquid effluents and of guideline values concerning radioactive wastes, briefly presents the surveillance of underground and surface waters of CEA sites, comments the guideline values of the radiological quality of waters aimed at human consumption, and gives an overview of information which are brought to public's attention. Then, for different CEA sites (Cadarache, Marcoule, Saclay, Grenoble, Fontenay-aux-Roses, Valduc, DIF), this document proposes a presentation of the hydrological context, regulatory context, the surface and underground water surveillance process and values, the storing zones of old wastes.

SU-F-T-684: Analysis of Cherenkov Excitation in Tissue and the Feasibility of Cherenkov Excited Photodynamic Therapy

International Nuclear Information System (INIS)

Saunders, Sara L; Andreozzi, Jacqueline M; Pogue, Brian W; Glaser, Adam K

2016-01-01

Purpose: The irradiation of photodynamic agents with radiotherapy beams has been demonstrated to enhance tumor killing in various studies, and one proposed mechanism is the optical fluence of Cherenkov emission activating the photosensitizer. This mechanism is explored in Monte Carlo simulations of fluence as well as laboratory measurements of fluence and radical oxygen species. Methods: Simulations were completed using GAMOS/GEANT4 with a 6 MV photon beam in tissue. The effects of blood vessel diameter, blood oxygen saturation, and beam size were examined, recording spectral fluence. Experiments were carried out in solutions of photosensitizer and phantoms. Results: Cherenkov produced by a 100×100um"2 6 MV beam resulted in fluence of less than 1 nJ/cm"2/Gy per 1 nm wavelength. At this microscopic level, differences in absorption of blood and water in the tissue affected the fluence spectrum, but variation in blood oxygenation had little effect. Light in tissue resulting from larger (10mm ×10mm) 6 MV beams had greater fluence due to light transport and elastic scattering of optical photons, but this transport process also resulted in higher absorption shifts. Therefore, the spectrum produced by a microscopic beam was weighted more heavily in UV/blue wavelengths than the spectrum at the macroscopic level. At the macroscopic level, the total fluence available for absorption by Verteporfin (BPD) in tissue approached uJ/cm"2 for a high radiation dose, indicating that photodynamic activation seems unlikely. Tissue phantom confirmation of these light levels supported this observation, and photosensitization measurements with a radical oxygen species reporter are ongoing. Conclusion: Simulations demonstrated that fluence produced by Cherenkov in tissue by 6 MV photon beams at typical radiotherapy doses appears insufficient to activate photosensitizers to the level required for threshold effects, yet this disagrees with published biological experiments. Experimental

SU-F-T-684: Analysis of Cherenkov Excitation in Tissue and the Feasibility of Cherenkov Excited Photodynamic Therapy

Energy Technology Data Exchange (ETDEWEB)

Saunders, Sara L; Andreozzi, Jacqueline M; Pogue, Brian W [Dartmouth College, Hanover, NH (United States); Glaser, Adam K [University of Washington, Seattle, WA (United States)

2016-06-15

Purpose: The irradiation of photodynamic agents with radiotherapy beams has been demonstrated to enhance tumor killing in various studies, and one proposed mechanism is the optical fluence of Cherenkov emission activating the photosensitizer. This mechanism is explored in Monte Carlo simulations of fluence as well as laboratory measurements of fluence and radical oxygen species. Methods: Simulations were completed using GAMOS/GEANT4 with a 6 MV photon beam in tissue. The effects of blood vessel diameter, blood oxygen saturation, and beam size were examined, recording spectral fluence. Experiments were carried out in solutions of photosensitizer and phantoms. Results: Cherenkov produced by a 100×100um{sup 2} 6 MV beam resulted in fluence of less than 1 nJ/cm{sup 2}/Gy per 1 nm wavelength. At this microscopic level, differences in absorption of blood and water in the tissue affected the fluence spectrum, but variation in blood oxygenation had little effect. Light in tissue resulting from larger (10mm ×10mm) 6 MV beams had greater fluence due to light transport and elastic scattering of optical photons, but this transport process also resulted in higher absorption shifts. Therefore, the spectrum produced by a microscopic beam was weighted more heavily in UV/blue wavelengths than the spectrum at the macroscopic level. At the macroscopic level, the total fluence available for absorption by Verteporfin (BPD) in tissue approached uJ/cm{sup 2} for a high radiation dose, indicating that photodynamic activation seems unlikely. Tissue phantom confirmation of these light levels supported this observation, and photosensitization measurements with a radical oxygen species reporter are ongoing. Conclusion: Simulations demonstrated that fluence produced by Cherenkov in tissue by 6 MV photon beams at typical radiotherapy doses appears insufficient to activate photosensitizers to the level required for threshold effects, yet this disagrees with published biological experiments

UNDERGROUND

International Nuclear Information System (INIS)

Anon.

1993-01-01

Full text: Cossetted deep underground, sheltered from cosmic ray noise, has always been a favourite haunt of neutrino physicists. Already in the 1930s, significant limits were obtained by taking a geiger counter down in Holborn 'tube' station, one of the deepest in London's underground system. Since then, neutrino physicists have popped up in many unlikely places - gold mines, salt mines, and road tunnels deep under mountain chains. Two such locations - the 1MB (Irvine/ Michigan/Brookhaven) detector 600 metres below ground in an Ohio salt mine, and the Kamiokande apparatus 1000m underground 300 km west of Tokyo - picked up neutrinos on 23 February 1987 from the famous 1987A supernova. Purpose-built underground laboratories have made life easier, notably the Italian Gran Sasso Laboratory near Rome, 1.4 kilometres below the surface, and the Russian Baksan Neutrino Observatory under Mount Andyrchi in the Caucasus range. Gran Sasso houses ICARUS (April, page 15), Gallex, Borexino, Macro and the LVD Large Volume Detector, while Baksan is the home of the SAGE gallium-based solar neutrino experiment. Elsewhere, important ongoing underground neutrino experiments include Soudan II in the US (April, page 16), the Canadian Sudbury Neutrino Observatory with its heavy water target (January 1990, page 23), and Superkamiokande in Japan (May 1991, page 8)

CHerenkov detectors In mine PitS (CHIPS) Letter of Intent to FNAL

Energy Technology Data Exchange (ETDEWEB)

Adamson, P. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Austin, J. [Univ. of Minnesota, Duluth, MN (United States); Cao, S. V. [Univ. of Texas, Austin, TX (United States); Coelho, J. A. B. [Tufts Univ., Medford, MA (United States); Davies, G. S. [Iowa State Univ., Ames, IA (United States); Evans, J. J. [Univ. of Manchester (United Kingdom); Guzowski, P. [Univ. of Manchester (United Kingdom); Habig, A. [Univ. of Minnesota, Duluth, MN (United States); Holin, A. [Univ. College London, London (United Kingdom); Huang, J. [Univ. of Texas, Austin, TX (United States); Johnson, R. [Univ. of Cincinnati, OH (United States); St. John, J. [Univ. of Cincinnati, OH (United States); Kreymer, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Kordosky, M. [College of William and Mary, Williamsburg, VA (United States); Lang, K. [Univ. of Texas, Austin, TX (United States); Marshak, M. L. [Univ. of Minnesota, Minneapolis, MN (United States); Mehdiyev, R. [Univ. of Texas, Austin, TX (United States); Meier, J. [Univ. of Minnesota, Minneapolis, MN (United States); Miller, W. [Univ. of Minnesota, Minneapolis, MN (United States); Naples, D. [Univ. of Pittsburgh, PA (United States); Nelson, J. K. [College of William and Mary, Williamsburg, VA (United States); Nichol, R. J. [Univ. College London, London (United Kingdom); Patterson, R. B. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Paolone, V. [Univ. of Pittsburgh, PA (United States); Pawloski, G. [Univ. of Minnesota, Minneapolis, MN (United States); Perch, A. [Univ. College London, London (United Kingdom); Pfutzner, M. [Univ. College London, London (United Kingdom); Proga, M. [Univ. of Texas, Austin, TX (United States); Qian, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Radovic, A. [Univ. College London, London (United Kingdom); Sanchez, M. C. [Iowa State Univ., Ames, IA (United States); Schreiner, S. [Univ. of Minnesota, Minneapolis, MN (United States); Soldner-Rembold, S. [Univ. of Manchester (United Kingdom); Sousa, A. [Univ. of Cincinnati, OH (United States); Thomas, J. [Univ. College London, London (United Kingdom); Vahle, P. [College of William and Mary, Williamsburg, VA (United States); Wendt, C. [Univ. of Wisconsin, Madison, WI (United States); Whitehead, L. H. [Univ. College London, London (United Kingdom); Wojcicki, S. [Stanford Univ., CA (United States)

2013-12-30

This Letter of Intent outlines a proposal to build a large, yet cost-effective, 100 kton fiducial mass water Cherenkov detector that will initially run in the NuMI beam line. The CHIPS detector (CHerenkov detector In Mine PitS) will be deployed in a flooded mine pit, removing the necessity and expense of a substantial external structure capable of supporting a large detector mass. There are a number of mine pits in northern Minnesota along the NuMI beam that could be used to deploy such a detector. In particular, the Wentworth Pit 2W is at the ideal off-axis angle to contribute to the measurement of the CP violating phase. The detector is designed so that it can be moved to a mine pit in the LBNE beam line once that becomes operational.

CHERENKOV RADIATION DETECTOR

African Journals Online (AJOL)

ES Obe

1981-03-01

Mar 1, 1981 ... to measure the Cherenkov angles for natural radioactivity from sources as. Cs137 ... at 435 Mev in their proton-proton ..... (ii) Use is made of Table 5A Jelley ..... charge and rest mass in units of electron rest mass is shown in the table ... Proton e+. 1836. 322. Neutron. 0. 1839. 325. Alpha e2+. 7344. 1600.

DIRC, the internally reflecting ring imaging Cherenkov detector for BABAR

International Nuclear Information System (INIS)

Adam, I.; Aston, D.

1997-11-01

The DIRC is a new type of Cherenkov imaging device that will be used for the first time in the BABAR detector at the asymmetric B-factory, PEP-II. It is based on total internal reflection and uses long, rectangular bars made from synthetic fused silica as Cherenkov radiator and light guide. The principles of the DIRC ring imaging Cherenkov technique are explained and results from the prototype program are presented. Its choice for the BABAR detector particle identification system is motivated, followed by a discussion of the quartz radiator properties and the detector design

Operating performance of the gamma-ray Cherenkov telescope: An end-to-end Schwarzschild–Couder telescope prototype for the Cherenkov Telescope Array

Energy Technology Data Exchange (ETDEWEB)

Dournaux, J.L., E-mail: jean-laurent.dournaux@obspm.fr [GEPI, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Paris Cité, Université Paris Diderot, Place J. Janssen, 92190 Meudon (France); De Franco, A. [Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Laporte, P. [GEPI, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Paris Cité, Université Paris Diderot, Place J. Janssen, 92190 Meudon (France); White, R. [Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Greenshaw, T. [University of Liverpool, Oliver Lodge Laboratory, P.O. Box 147, Oxford Street, Liverpool L69 3BX (United Kingdom); Sol, H. [LUTH, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Place J. Janssen, 92190 Meudon (France); Abchiche, A. [CNRS, Division technique DT-INSU, 1 Place Aristide Briand, 92190 Meudon (France); Allan, D. [Department of Physics and Centre for Advanced Instrumentation, Durham University, South Road, Durham DH1 3LE (United Kingdom); Amans, J.P. [GEPI, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Paris Cité, Université Paris Diderot, Place J. Janssen, 92190 Meudon (France); Armstrong, T.P. [Department of Physics and Centre for Advanced Instrumentation, Durham University, South Road, Durham DH1 3LE (United Kingdom); Balzer, A.; Berge, D. [GRAPPA, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Boisson, C. [LUTH, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Place J. Janssen, 92190 Meudon (France); and others

2017-02-11

The Cherenkov Telescope Array (CTA) consortium aims to build the next-generation ground-based very-high-energy gamma-ray observatory. The array will feature different sizes of telescopes allowing it to cover a wide gamma-ray energy band from about 20 GeV to above 100 TeV. The highest energies, above 5 TeV, will be covered by a large number of Small-Sized Telescopes (SSTs) with a field-of-view of around 9°. The Gamma-ray Cherenkov Telescope (GCT), based on Schwarzschild–Couder dual-mirror optics, is one of the three proposed SST designs. The GCT is described in this contribution and the first images of Cherenkov showers obtained using the telescope and its camera are presented. These were obtained in November 2015 in Meudon, France.

Selective Filtration of Gadolinium Trichloride for Use in Neutron Detection in Large Water Cherenkov Detectors

International Nuclear Information System (INIS)

Vagins, Mark R.

2013-01-01

Super-??Kamiokande Water Cherenkov detectors have been used for many years as inexpensive, effective detectors for neutrino interactions and nucleon decay searches. While many important measurements have been made with these detectors a major drawback has been their inability to detect the absorption of thermal neutrons. We believe an inexpensive, effective technique could be developed to overcome this situation via the addition to water of a solute with a large neutron cross section and energetic gamma daughters which would make neutrons detectable. Gadolinium seems an excellent candidate especially since in recent years it has become very inexpensive, now less than $8 per kilogram in the form of commercially-available gadolinium trichloride, GdCl 3 . This non-toxic, non-reactive substance is highly soluble in water. Neutron capture on gadolinium yields a gamma cascade which would be easily seen in detectors like Super-Kamiokande. We have been investigating the use of GdCl 3 as a possible upgrade for the Super-Kamiokande detector with a view toward improving its performance as a detector for atmospheric neutrinos, supernova neutrinos, wrong-sign solar neutrinos, reactor neutrinos, proton decay, and also as a target for the coming T2K long-baseline neutrino experiment. This focused study of selective water filtration and GdCl 3 extraction techniques, conducted at UC Irvine, followed up on highly promising benchtop-scale and kiloton-scale work previously carried out with the assistance of 2003 and 2005 Advanced Detector Research Program grants

Research for Preseismic Phenomena on the Underground Water Level and Temperature in Selected Areas of Greece

Science.gov (United States)

Contadakis, M. E.; Asteriadis, G.

1997-08-01

A comprehensive study of the tectonic activity require the contribution of a variety of methods, geological, seismic, geodetic, satellite etc., being currently available in our days. On the other hand, the risk evaluation in areas of high seismicity, like this one of the South Balkan Peninsula, is of vital importance. To this purpose an interdisciplinary following up of the tectonic activity in the area may provide the best provision to the administration for an effective confrontation and intervention for the elimination of the possible disastrous effects in human life cost, financial and social cost of the communities, to which may result a strong earthquake. Among the various methods of indirect monitoring of the tectonic activity in an area, which in addition is of a low cost, is that of the following up of the underground water level and temperature changes in the area of interest. This method is based on the fact that tectonic activity is expected to result to tectonic stresses producing alterations to the local water table which in its turn is expected is expected to be observed as variation of the underground water level and temperature. The method of the following up of the underground water and temperature changes has been applied, among others by the Department of Geodesy and Surveying of the University of Thessaloniki in two areas of high seismicity in Greece: (a) The seismic zone of the lake Volvi in North Greece (40.5 deg N and 23.5 deg E) for ten years (1983-1992) and (b) the area of South Thessaly (39.2 deg N and 21 deg E) for three years (1994-1996). The statistical analysis of the observations, shows that the low frequency constituent (Sa,Ssa,Mf,Mm) of the earth tides and the barometric pressure have a small influence on the water level measurements. The shallow underground water network of South Thessaly is more sensitive to the non tectonic factors than the network of Volvi. Tentative correlation of the underground wat! er and temperature

Bio-chemical remediation of under-ground water contaminated by uranium in-situ leaching

International Nuclear Information System (INIS)

Wang Qingliang; Li Qian; Zhang Hongcan; Hu Eming; Chen Yongbo

2014-01-01

In the process of uranium in-situ leaching, it was serious that strong acid, uranium and heavy metals, and SO_4"2"-, NO_3"- could contaminate underground water. To remedy these pollutants, conventional methods are high-cost and low-efficient, so a bio-chemical remediation method was proposed to cope with the under-ground water pollution in this study. The results showed, in the chemical treatment with Ca(OH)_2 neutralization, pH went up from 2.0 to 7.0, the removal rates of U, Mn"2"+, Zn"2"+, Pb"2"+, SO_4"2"-, NO_3"- were 91.5%, 78.3%, 85.1%, 100%, 71.4% and 2.6% respectively, SO_4"2"- and NO_3"- need to be treated again by bio-method. In the biological process, the Hydraulic Retention Time (HRT) of bioreactor was controlled at 42 h, and 100% NO_3"- and 70% SO_4"2"- in the contaminated water were removed; Acidithiobacillus ferrooxidans (A. f) liquid to H_2S showed better absorption effect, can fully meet the process requirements of H_2S removal. (authors)

Cherenkov Radiation Control via Self-accelerating Wave-packets.

Science.gov (United States)

Hu, Yi; Li, Zhili; Wetzel, Benjamin; Morandotti, Roberto; Chen, Zhigang; Xu, Jingjun

2017-08-18

Cherenkov radiation is a ubiquitous phenomenon in nature. It describes electromagnetic radiation from a charged particle moving in a medium with a uniform velocity larger than the phase velocity of light in the same medium. Such a picture is typically adopted in the investigation of traditional Cherenkov radiation as well as its counterparts in different branches of physics, including nonlinear optics, spintronics and plasmonics. In these cases, the radiation emitted spreads along a "cone", making it impractical for most applications. Here, we employ a self-accelerating optical pump wave-packet to demonstrate controlled shaping of one type of generalized Cherenkov radiation - dispersive waves in optical fibers. We show that, by tuning the parameters of the wave-packet, the emitted waves can be judiciously compressed and focused at desired locations, paving the way to such control in any physical system.

High-Energy Neutron Backgrounds for Underground Dark Matter Experiments

Energy Technology Data Exchange (ETDEWEB)

Chen, Yu [Syracuse Univ., NY (United States)

2016-01-01

Direct dark matter detection experiments usually have excellent capability to distinguish nuclear recoils, expected interactions with Weakly Interacting Massive Particle (WIMP) dark matter, and electronic recoils, so that they can efficiently reject background events such as gamma-rays and charged particles. However, both WIMPs and neutrons can induce nuclear recoils. Neutrons are then the most crucial background for direct dark matter detection. It is important to understand and account for all sources of neutron backgrounds when claiming a discovery of dark matter detection or reporting limits on the WIMP-nucleon cross section. One type of neutron background that is not well understood is the cosmogenic neutrons from muons interacting with the underground cavern rock and materials surrounding a dark matter detector. The Neutron Multiplicity Meter (NMM) is a water Cherenkov detector capable of measuring the cosmogenic neutron flux at the Soudan Underground Laboratory, which has an overburden of 2090 meters water equivalent. The NMM consists of two 2.2-tonne gadolinium-doped water tanks situated atop a 20-tonne lead target. It detects a high-energy (>~ 50 MeV) neutron via moderation and capture of the multiple secondary neutrons released when the former interacts in the lead target. The multiplicity of secondary neutrons for the high-energy neutron provides a benchmark for comparison to the current Monte Carlo predictions. Combining with the Monte Carlo simulation, the muon-induced high-energy neutron flux above 50 MeV is measured to be (1.3 ± 0.2) ~ 10-9 cm-2s-1, in reasonable agreement with the model prediction. The measured multiplicity spectrum agrees well with that of Monte Carlo simulation for multiplicity below 10, but shows an excess of approximately a factor of three over Monte Carlo prediction for multiplicities ~ 10 - 20. In an effort to reduce neutron backgrounds for the dark matter experiment SuperCDMS SNO- LAB, an active neutron veto was developed

Behaviors of radionuclides in wet underground soil

International Nuclear Information System (INIS)

Inoue, Y.; Morisawa, S.

Experimental studies were made of the variations of the distribution coefficient of 65 Zn, 60 Co, and /sup 110 m/Ag with Ca ion contents in sand--water and resin--water systems. It is concluded that: (1) The distribution coefficient of a radionuclide is not constant but varies greatly especially with calcium ion concentration in underground water. (2) The Saturation Index I=pH-pHs can be used as a parameter to indicate such variations. (3) Some radionuclides, existing as radiocolloids like (sup 110m/Ag and 59 Fe, are inactive toward ion exchange reactions as with hydroxide. In such cases, the nuclides migrate underground as fast as underground water

Cherenkov rings from aerogel detected by four large-area hybrid photodiodes

International Nuclear Information System (INIS)

Bellunato, T.; Braem, A.; Buzykaev, A.R.; Calvi, M.; Chesi, E.; Danilyuk, A.F.; Easo, S.; Jolly, S.; Joram, C.; Kravchenko, E.A.; Liko, D.; Matteuzzi, C.; Musy, M.; Negri, P.; Neufeld, N.; Onuchin, A.P.; Seguinot, J.; Wotton, S.

2003-01-01

We report on the results obtained using thick samples of silica aerogel as radiators for a Ring Imaging Cherenkov counter. Four large-diameter hybrid photodiodes with 2048 channels have been used as photon detectors. Pions and protons with momenta ranging from 6 to 10 GeV/c were separated and identified. The number of photoelectrons and the radius of the Cherenkov rings together with the Cherenkov angle resolution were measured. A comparison with a simulation program based on GEANT4 is discussed

Volcanoes muon imaging using Cherenkov telescopes

Energy Technology Data Exchange (ETDEWEB)

Catalano, O. [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Del Santo, M., E-mail: melania@ifc.inaf.it [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Mineo, T.; Cusumano, G.; Maccarone, M.C. [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Pareschi, G. [INAF Osservatorio Astronomico di Brera, Via E. Bianchi 46, I-23807, Merate (Italy)

2016-01-21

A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

Volcanoes muon imaging using Cherenkov telescopes

International Nuclear Information System (INIS)

Catalano, O.; Del Santo, M.; Mineo, T.; Cusumano, G.; Maccarone, M.C.; Pareschi, G.

2016-01-01

A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

Micellar Enhanced Ultrafiltration for the Removal of Polycyclic Aromatic Hydrocarbons (PAHs Mixtures in Underground Contaminated Water in Oman

Directory of Open Access Journals (Sweden)

Mohamed Aoudia

2011-12-01

Full Text Available In an attempt to analyze polycyclic aromatic hydrocarbons (PAHs in diesel contaminated underground water in Oman (Rustaq, Gas chromatography-Mass spectrometry was first used to determine the different concentrations in a standard mixture containing 16 PAHs. Retention time and calibration curves were obtained for all aromatic compounds and were used to identify a given analyte as well as its concentration in the contaminated underground water. Micellar enhanced ultrafiltration (MEUF was then used to treat standard aqueous solution of PAHs at low concentration (~ 1 ppb using an edible nonionic surfactant (Tween 80. The totality of the mixture components was completely rejected. Within the experimental detection limit (± 0.01 ppb, the residual PAH concentrations were less than 0.01 ppb in accord with the allowed concentrations in drinking water. Likewise, excellent rejections of PAHs in MEUF treatment of diesel contaminated underground water at an Omani site (Rustaq were observed. The concentration of PAHs was reduced to less than 0.01 ppb, the accepted limit for the most toxic member of the PAH group (benzo(apyrene.

[Arsenic levels in drinking water supplies from underground sources in the community of Madrid].

Science.gov (United States)

Aragonés Sanz, N; Palacios Diez, M; Avello de Miguel, A; Gómez Rodríguez, P; Martínez Cortés, M; Rodríguez Bernabeu, M J

2001-01-01

In 1998, arsenic concentrations of more than 50 micrograms/l were detected in some drinking water supplies from underground sources in the Autonomous Community of Madrid, which is the maximum permissible concentration for drinking water in Spain. These two facts have meant the getting under way of a specific plan for monitoring arsenic in the drinking water in the Autonomous Community of Madrid. The results of the first two sampling processes conducted in the arsenic level monitoring plan set out are presented. In the initial phase, water samples from 353 water supplies comprised within the census of the Public Health Administration of the Autonomous Community of Madrid were analyzed. A water supply risk classification was made based on these initial results. In a second phase, six months later, the analyses were repeated on those 35 water supplies which were considered to possibly pose a risk to public health. Seventy-four percent (74%) of the water supplies studied in the initial phase were revealed to have an arsenic concentration of less than 10 micrograms/l, 22.6% containing levels of 10 micrograms/l-50 micrograms/l, and 3.7% over 50 micrograms/l. Most of the water supplies showing arsenic levels of more than 10 micrograms/l are located in the same geographical area. In the second sampling process (six months later), the 35 water supplies classified as posing a risk were included. Twenty-six (26) of these supplies were revealed to have the same arsenic level ((10-50 micrograms/l), and nine changed category, six of which had less than 10 micrograms/l and three more than 50 micrograms/l. In the Autonomous Community of Madrid, less than 2% of the population drinks water coming from supplies which are from underground sources. The regular water quality monitoring conducted by the Public Health Administration has led to detecting the presence of more than 50 micrograms/l of arsenic in sixteen drinking water supplies from underground sources, which is the maximum

An assessment study of septic tank based sewage disposal system on quality of underground water

International Nuclear Information System (INIS)

Khawaja, A.A.; Lisa, M.; Boustani, M.; Jaffar, M.; Masud, K.

1999-01-01

An assessment of septic tank based sewage disposal system made on the basis of quality of underground water is presented. Machrala village is selected as the case study area where an ever-increasing number of septic tanks are posing great health threat to the inhabitants. Both hand pump and tube well water samples are analyzed for toxic trace metals (Mn, Fe, Cd and Co), physico-chemical parameters (pH, turbidity, conductance, total dissolved salts, Ca, Mg, Cl/sup-/ and SO/sub 4//sup -2/) and micro-organism population in terms of total viable count, coliform count, MPN coliform. The metals were analyzed by the flame atomic absorption method using standard procedure. The study shows that the local underground water of the village is being adversely affected by toxic metals and coliform bacteria. In most cases, the latter parameter exceeds 240 counts/ml. Besides, tube well water were found to have higher Pb concentration (0.200 mg/ml) and the overall assessment renders more than 50% of the water samples as unsatisfactory for human consumption. (author)

Results of the radon concentration survey in Sibiu county underground water

International Nuclear Information System (INIS)

Chicea, Dan; Cosma, Constantin

2002-01-01

In November 2000 a survey of radon ( 222 Rn) concentration in Sibiu county underground water was conducted. The radon concentration was measured with a A LUK 3A. The radon gas was extracted from water using the LUK VR device that works with LUK 3A. All samples were taken in 0.5 l recipients that were filled and sealed. Samples from eighteen cities and villages were taken. Special care was taken for the samples to be carefully brought to room temperature and not to be agitated or stirred before measuring the radon concentration. In measuring the radon concentration corrections like the solubility coefficient variation with temperature, the radon concentration increase in air in time and the background correction were applied. Results reveal that the underground water radon concentration is bigger in wells located in mountainous area, has an average value in wells from hilly region and is considerable lower in wells located in plain area. Another thing we noticed is that the samples taken from the city water pipe system present lower radon concentration values than the samples taken from home drilled wells. The minimum radon concentration value was found in the drinking water of Sibiu city, 1.6 Bq/l and in Sadu village, 1.965 Bq/l. The highest measured values are 28.1 Bq/l in Rasinari, a village located at the bottom of the mountains and 26.4 Bq/l, in Sibiel, a village 30 km away from the first one. These results reveal that the radon concentration values measured in Sibiu county are comparable with the measured values reported in literature and well below the maximum acceptable values. (authors)

The GCT camera for the Cherenkov Telescope Array

Science.gov (United States)

Lapington, J. S.; Abchiche, A.; Allan, D.; Amans, J.-P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J.-J.; Bose, R.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Buckley, J.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Daniel, M. K.; De Franco, A.; De Frondat, F.; Dournaux, J.-L.; Dumas, D.; Ernenwein, J.-P.; Fasola, G.; Funk, S.; Gironnet, J.; Graham, J. A.; Greenshaw, T.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J.-M.; Jankowsky, D.; Jegouzo, I.; Jogler, T.; Kawashima, T.; Kraus, M.; Laporte, P.; Leach, S.; Lefaucheur, J.; Markoff, S.; Melse, T.; Minaya, I. A.; Mohrmann, L.; Molyneux, P.; Moore, P.; Nolan, S. J.; Okumura, A.; Osborne, J. P.; Parsons, R. D.; Rosen, S.; Ross, D.; Rowell, G.; Rulten, C. B.; Sato, Y.; Sayede, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Sol, H.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Trichard, C.; Varner, G.; Vink, J.; Watson, J. J.; White, R.; Yamane, N.; Zech, A.; Zink, A.; Zorn, J.; CTA Consortium

2017-12-01

The Gamma Cherenkov Telescope (GCT) is one of the designs proposed for the Small Sized Telescope (SST) section of the Cherenkov Telescope Array (CTA). The GCT uses dual-mirror optics, resulting in a compact telescope with good image quality and a large field of view with a smaller, more economical, camera than is achievable with conventional single mirror solutions. The photon counting GCT camera is designed to record the flashes of atmospheric Cherenkov light from gamma and cosmic ray initiated cascades, which last only a few tens of nanoseconds. The GCT optics require that the camera detectors follow a convex surface with a radius of curvature of 1 m and a diameter of 35 cm, which is approximated by tiling the focal plane with 32 modules. The first camera prototype is equipped with multi-anode photomultipliers, each comprising an 8×8 array of 6×6 mm2 pixels to provide the required angular scale, adding up to 2048 pixels in total. Detector signals are shaped, amplified and digitised by electronics based on custom ASICs that provide digitisation at 1 GSample/s. The camera is self-triggering, retaining images where the focal plane light distribution matches predefined spatial and temporal criteria. The electronics are housed in the liquid-cooled, sealed camera enclosure. LED flashers at the corners of the focal plane provide a calibration source via reflection from the secondary mirror. The first GCT camera prototype underwent preliminary laboratory tests last year. In November 2015, the camera was installed on a prototype GCT telescope (SST-GATE) in Paris and was used to successfully record the first Cherenkov light of any CTA prototype, and the first Cherenkov light seen with such a dual-mirror optical system. A second full-camera prototype based on Silicon Photomultipliers is under construction. Up to 35 GCTs are envisaged for CTA.

Tritium dating of underground water from the Jian River valley and Houjialiang loess platform in the basin side-band of the East-Mountain Region of Taiyuan

International Nuclear Information System (INIS)

Yu Songsheng; Wu Qinghua

1991-01-01

The tritium content is measured in underground water from the basin side-band of the East-Mountain Region of Taiyuan, Shanxi Province, and hence the age, i.e. resident time, of underground water is estimated. The region belongs to deep water-poor zone in a long loess ridge situated in a loess hill plateau. The level of underground water is 40-80 m deep hidden. In the runway and the scouring channel the aqueous bed is of river pebble and cobble, with a level of 2-10 m in depth. The age of underground water from different wells were determined to be 23a, 14a, 25a, 41a and 53a respectively

Quenching the scintillation in CF{sub 4} Cherenkov gas radiator

Energy Technology Data Exchange (ETDEWEB)

Blake, T. [Department of Physics, University of Warwick, Coventry (United Kingdom); D' Ambrosio, C. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Easo, S. [STFC Rutherford Appleton Laboratory, Didcot (United Kingdom); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Eisenhardt, S. [School of Physics and Astronomy, University of Edinburgh, Edinburgh (United Kingdom); Fitzpatrick, C. [Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Forty, R.; Frei, C. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Gibson, V. [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom); Gys, T. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Harnew, N.; Hunt, P. [Department of Physics, University of Oxford, Oxford (United Kingdom); Jones, C.R. [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom); Lambert, R.W. [Nikhef National Institute for Subatomic Physics and VU University Amsterdam, Amsterdam (Netherlands); Matteuzzi, C. [Sezione INFN di Milano Bicocca, Milano (Italy); Muheim, F. [School of Physics and Astronomy, University of Edinburgh, Edinburgh (United Kingdom); Papanestis, A., E-mail: antonis.papanestis@stfc.ac.uk [STFC Rutherford Appleton Laboratory, Didcot (United Kingdom); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Perego, D.L. [Sezione INFN di Milano Bicocca, Milano (Italy); Università di Milano Bicocca, Milano (Italy); Piedigrossi, D. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Plackett, R. [Imperial College London, London (United Kingdom); Powell, A. [Department of Physics, University of Oxford, Oxford (United Kingdom); and others

2015-08-11

CF{sub 4} is used as a Cherenkov gas radiator in one of the Ring Imaging Cherenkov detectors at the LHCb experiment at the CERN Large Hadron Collider. CF{sub 4} is well known to have a high scintillation photon yield in the near and far VUV, UV and in the visible wavelength range. A large flux of scintillation photons in our photon detection acceptance between 200 and 800 nm could compromise the particle identification efficiency. We will show that this scintillation photon emission system can be effectively quenched, consistent with radiationless transitions, with no significant impact on the photons resulting from Cherenkov radiation.

Silica aerogel Cherenkov counter for the KEK B-factory experiment

CERN Document Server

Sumiyoshi, T; Enomoto, R; Iijima, T; Suda, R; Leonidopoulos, C; Marlow, D R; Prebys, E; Kawabata, R; Kawai, H; Ooba, T; Nanao, M; Suzuki, K; Ogawa, S; Murakami, A; Khan, M H R

1999-01-01

Low-refractive-index silica aerogel is a convenient radiator for threshold-type Cherenkov counters, which are used for particle identification in high-energy physics experiments. For the BELLE detector at the KEK B-Factory we have produced about 2 m sup 3 of hydrophobic silica aerogels of n=1.01-1.03 using a new production method. The particle identification capability of the aerogel Cherenkov counters was tested and 3 sigma pion/proton separation has been achieved at 3.5 GeV/c. Radiation hardness of the aerogels was confirmed up to 9.8 Mrad. The Aerogel Cherenkov counter system (ACC) was successfully installed in the BELLE just before this conference.

In-beam test of a DIRC Cherenkov radiator with SiPM

International Nuclear Information System (INIS)

Kroeck, B.; Hayrapetyan, A.; Foehl, K.; Merle, O.; Dueren, M.; Roy, B.J.; Peters, K.

2009-01-01

One of the crucial points for any high energy physics experiment is to obtain a good pion/kaon separation i.e. particle identification (PID). For particles in minimum ionising range, the conventional methods of PID using energy loss and time of flight become insufficient. In such a situation, the measurement of velocity of particles using Cherenkov radiation is an effective tool for PID in combination with momentum information from a tracking detector. The PANDA experiment at FAIR/ GSI plans to use a novel technique for PID with detection of internally reflected Cherenkov (DIRC) light. DIRC uses, in contrast to the conventional gas Cherenkov detectors, a solid radiator and total internal reflection to guide Cherenkov photons onto a detection plane where it will be detected by advanced photon counters. A SiPM is a very new generation photon counter that has several advantages over conventional PMTs. Several prototype Cherenkov detectors with different readout systems are being developed for R and D studies. One such prototype detector with Geiger-APD readout has been built at Giessen and was tested in-beam at GSI. The present report provides details of the very first test measurement

Geostatistical analysis of space variation in underground water various quality parameters in Kłodzko water intake area (SW part of Poland

Directory of Open Access Journals (Sweden)

Namysłowska-Wilczyńska Barbara

2016-09-01

Full Text Available This paper presents selected results of research connected with the development of a (3D geostatistical hydrogeochemical model of the Kłodzko Drainage Basin, dedicated to the spatial variation in the different quality parameters of underground water in the water intake area (SW part of Poland. The research covers the period 2011-2012. Spatial analyses of the variation in various quality parameters, i.e., contents of: iron, manganese, ammonium ion, nitrate ion, phosphate ion, total organic carbon, pH redox potential and temperature, were carried out on the basis of the chemical determinations of the quality parameters of underground water samples taken from the wells in the water intake area. Spatial variation in the parameters was analyzed on the basis of data obtained (November 2011 from tests of water taken from 14 existing wells with a depth ranging from 9.5 to 38.0 m b.g.l. The latest data (January 2012 were obtained (gained from 3 new piezometers, made in other locations in the relevant area. A depth of these piezometers amounts to 9-10 m.

Color quench correction for low level Cherenkov counting.

Science.gov (United States)

Tsroya, S; Pelled, O; German, U; Marco, R; Katorza, E; Alfassi, Z B

2009-05-01

The Cherenkov counting efficiency varies strongly with color quenching, thus correction curves must be used to obtain correct results. The external (152)Eu source of a Quantulus 1220 liquid scintillation counting (LSC) system was used to obtain a quench indicative parameter based on spectra area ratio. A color quench correction curve for aqueous samples containing (90)Sr/(90)Y was prepared. The main advantage of this method over the common spectra indicators is its usefulness also for low level Cherenkov counting.

The Cherenkov correlated timing detector: beam test results from quartz and acrylic bars

International Nuclear Information System (INIS)

Kichimi, H.; Sugaya, Y.; Yamaguchi, H.; Yoshimura, Y.; Kanda, S.; Olsen, S.; Ueno, K.; Varner, G.; Bergfeld, T.; Bialek, J.; Lorenc, J.; Palmer, M.; Rudnick, G.; Selen, M.; Auran, T.; Boyer, V.; Honscheid, K.; Tamura, N.; Yoshimura, K.; Lu, C.; Marlow, D.; Mindas, C.; Prebys, E.; Asai, M.; Kimura, A.; Hayashi, S.

1996-01-01

Several prototypes of a Cherenkov correlated timing (CCT) detector have been tested at the KEK-PS test beam line. We describe the results for Cherenkov light yields and timing characteristics from quartz and acrylic bar prototypes. A Cherenkov angle resolution is found to be 15 mrad at a propagation distance of 100 cm with a 2 cm thick quartz bar prototype. (orig.)

Reducing drinking water supply chemical contamination: risks from underground storage tanks.

Science.gov (United States)

Enander, Richard T; Hanumara, R Choudary; Kobayashi, Hisanori; Gagnon, Ronald N; Park, Eugene; Vallot, Christopher; Genovesi, Richard

2012-12-01

Drinking water supplies are at risk of contamination from a variety of physical, chemical, and biological sources. Ranked among these threats are hazardous material releases from leaking or improperly managed underground storage tanks located at municipal, commercial, and industrial facilities. To reduce human health and environmental risks associated with the subsurface storage of hazardous materials, government agencies have taken a variety of legislative and regulatory actions--which date back more than 25 years and include the establishment of rigorous equipment/technology/operational requirements and facility-by-facility inspection and enforcement programs. Given a history of more than 470,000 underground storage tank releases nationwide, the U.S. Environmental Protection Agency continues to report that 7,300 new leaks were found in federal fiscal year 2008, while nearly 103,000 old leaks remain to be cleaned up. In this article, we report on an alternate evidence-based intervention approach for reducing potential releases from the storage of petroleum products (gasoline, diesel, kerosene, heating/fuel oil, and waste oil) in underground tanks at commercial facilities located in Rhode Island. The objective of this study was to evaluate whether a new regulatory model can be used as a cost-effective alternative to traditional facility-by-facility inspection and enforcement programs for underground storage tanks. We conclude that the alternative model, using an emphasis on technical assistance tools, can produce measurable improvements in compliance performance, is a cost-effective adjunct to traditional facility-by-facility inspection and enforcement programs, and has the potential to allow regulatory agencies to decrease their frequency of inspections among low risk facilities without sacrificing compliance performance or increasing public health risks. © 2012 Society for Risk Analysis.

Cherenkov luminescence measurements with digital silicon photomultipliers: a feasibility study

Energy Technology Data Exchange (ETDEWEB)

Ciarrocchi, Esther; Belcari, Nicola; Guerra, Alberto Del [Department of Physics, University of Pisa, Pisa (Italy); INFN, section of Pisa, Pisa (Italy); Cherry, Simon R. [Department of Biomedical Engineering, University of California, Davis, CA (United States); Lehnert, Adrienne; Hunter, William C. J.; McDougald, Wendy; Miyaoka, Robert S.; Kinahan, Paul E. [Department of Radiology, University of Washington, Seattle, WA (United States)

2015-11-16

A feasibility study was done to assess the capability of digital silicon photomultipliers to measure the Cherenkov luminescence emitted by a β source. Cherenkov luminescence imaging (CLI) is possible with a charge coupled device (CCD) based technology, but a stand-alone technique for quantitative activity measurements based on Cherenkov luminescence has not yet been developed. Silicon photomultipliers (SiPMs) are photon counting devices with a fast impulse response and can potentially be used to quantify β-emitting radiotracer distributions by CLI. In this study, a Philips digital photon counting (PDPC) silicon photomultiplier detector was evaluated for measuring Cherenkov luminescence. The PDPC detector is a matrix of avalanche photodiodes, which were read one at a time in a dark count map (DCM) measurement mode (much like a CCD). This reduces the device active area but allows the information from a single avalanche photodiode to be preserved, which is not possible with analog SiPMs. An algorithm to reject the noisiest photodiodes and to correct the measured count rate for the dark current was developed. The results show that, in DCM mode and at (10–13) °C, the PDPC has a dynamic response to different levels of Cherenkov luminescence emitted by a β source and transmitted through an opaque medium. This suggests the potential for this approach to provide quantitative activity measurements. Interestingly, the potential use of the PDPC in DCM mode for direct imaging of Cherenkov luminescence, as a opposed to a scalar measurement device, was also apparent. We showed that a PDPC tile in DCM mode is able to detect and image a β source through its Cherenkov radiation emission. The detector’s dynamic response to different levels of radiation suggests its potential quantitative capabilities, and the DCM mode allows imaging with a better spatial resolution than the conventional event-triggered mode. Finally, the same acquisition procedure and data processing could

Cherenkov luminescence measurements with digital silicon photomultipliers: a feasibility study

International Nuclear Information System (INIS)

Ciarrocchi, Esther; Belcari, Nicola; Guerra, Alberto Del; Cherry, Simon R.; Lehnert, Adrienne; Hunter, William C. J.; McDougald, Wendy; Miyaoka, Robert S.; Kinahan, Paul E.

2015-01-01

A feasibility study was done to assess the capability of digital silicon photomultipliers to measure the Cherenkov luminescence emitted by a β source. Cherenkov luminescence imaging (CLI) is possible with a charge coupled device (CCD) based technology, but a stand-alone technique for quantitative activity measurements based on Cherenkov luminescence has not yet been developed. Silicon photomultipliers (SiPMs) are photon counting devices with a fast impulse response and can potentially be used to quantify β-emitting radiotracer distributions by CLI. In this study, a Philips digital photon counting (PDPC) silicon photomultiplier detector was evaluated for measuring Cherenkov luminescence. The PDPC detector is a matrix of avalanche photodiodes, which were read one at a time in a dark count map (DCM) measurement mode (much like a CCD). This reduces the device active area but allows the information from a single avalanche photodiode to be preserved, which is not possible with analog SiPMs. An algorithm to reject the noisiest photodiodes and to correct the measured count rate for the dark current was developed. The results show that, in DCM mode and at (10–13) °C, the PDPC has a dynamic response to different levels of Cherenkov luminescence emitted by a β source and transmitted through an opaque medium. This suggests the potential for this approach to provide quantitative activity measurements. Interestingly, the potential use of the PDPC in DCM mode for direct imaging of Cherenkov luminescence, as a opposed to a scalar measurement device, was also apparent. We showed that a PDPC tile in DCM mode is able to detect and image a β source through its Cherenkov radiation emission. The detector’s dynamic response to different levels of radiation suggests its potential quantitative capabilities, and the DCM mode allows imaging with a better spatial resolution than the conventional event-triggered mode. Finally, the same acquisition procedure and data processing could

El Nino and ground/underground water decreasing effects on coffee cultivation in DakNong Province, Vietnam by using GIS.

Science.gov (United States)

Duong, Anh Quan; Quy Bui, Ngoc; Luu, The Anh; Kainz, Wolfgang

2014-05-01

El Nino is one of most common climatic events which are widely spread over the world. In case of Vietnam, the El Nino or ENSO event has various effects on agricultural cultivation over whole country; in the Central Highlands area, the coffee cultivation also has been affected heavily. The coffee is one of most important products of this area. Our study area, the Dak Nong province located in the Central Highlands, the mountainous and highlands in central of Vietnam. The coffee production contributes roughly 40% of total GDP of the province. This province climate is influenced by tropical monsoon and high altitude terrain. The area has two seasons in which dry season from November to end of March and the wet season cover the rest. There is 80-90% of precipitation concentrated in wet season. In El Nino years, the dry season is longer and drier than normal which affects the agricultural cultivation especially coffee. The effects of El Nino phenomenon on coffee cultivation need to clarify in order to help farmers and decision makers making their solutions. The ground/underground water has been decreased by over watering of coffee growers as well as deforestation making water shortage in dry season. The over watering of coffee cultivation wasted more than 80% water resources especially underground water use. In years of 1997-1998, coffee productivity decreased 30%; in years of 2003, the coffee productivity was downed by 25%; both examples show the relation between the combination of ENSO and decreasing of Ground/underground water and the coffee production in Dak Nong province. This is a necessary research to evaluate the effects of the combination. This paper using GIS tools to estimate the effects of El Nino phenomenon combined with ground/underground water and the coffee cultivation in Dak Nong province

Light-weight spherical mirrors for Cherenkov detectors

CERN Document Server

Cisbani, E; Colilli, S; Crateri, R; Cusanno, F; De Leo, R; Fratoni, R; Frullani, S; Garibaldi, F; Giuliani, F; Gricia, M; Iodice, M; Iommi, R; Lagamba, L; Lucentini, M; Mostarda, A; Nappi, E; Pierangeli, L; Santavenere, F; Urciuoli, G M; Vernin, P

2003-01-01

Light-weight spherical mirrors have been appositely designed and built for the gas threshold Cherenkov detectors of the two Hall A spectrometers. The mirrors are made of a 1 mm thick aluminized plexiglass sheet, reinforced by a rigid backing consisting of a phenolic honeycomb sandwiched between two carbon fiber mats epoxy glued. The produced mirrors have a thickness equivalent to 0.55% of radiation length, and an optical slope error of about 5.5 mrad. These characteristics make these mirrors suitable for the implementation in Cherenkov threshold detectors. Ways to improve the mirror features are also discussed in view of their possible employment in RICH detectors.

On the kinematics of the two-photon Cherenkov effect

International Nuclear Information System (INIS)

Afanas'ev, G.N.; Stepanovskij, Yu.P.

2003-01-01

We study the kinematics of the two-photon Cherenkov effect. In the general case, the emission angles of two photons satisfy certain inequalities and the corresponding radiation intensities are rather diffused. In special cases, when the above inequalities reduce to equalities, the emission angles of two photons are fixed and the corresponding radiation intensities should have sharp maxima at these angles. This makes easier the experimental study of the two-photon Cherenkov effect

Groundwater and underground coal gasification in Alberta

International Nuclear Information System (INIS)

Haluszka, A.; MacMillan, G.; Maev, S.

2010-01-01

Underground coal gasification has potential in Alberta. This presentation provided background information on underground coal gasification and discussed groundwater and the Laurus Energy demonstration project. A multi-disciplined approach to project assessment was described with particular reference to geologic and hydrogeologic setting; geologic mapping; and a hydrogeologic numerical model. Underground coal gasification involves the conversion of coal into synthesis gas or syngas. It can be applied to mined coal at the surface or applied to non-mined coal seams using injection and production wells. Underground coal gasification can effect groundwater as the rate of water influx into the coal seams influences the quality and composition of the syngas. Byproducts created include heat as well as water with dissolved concentrations of ammonia, phenols, salts, polyaromatic hydrocarbons, and liquid organic products from the pyrolysis of coal. A process overview of underground coal gasification was also illustrated. It was concluded that underground coal gasification has the potential in Alberta and risks to groundwater could be minimized by a properly designed project. refs., figs.

Management of an Underground River to Overcome Water Scarcity in the Gunung Sewu Karst Area, Indonesia

Directory of Open Access Journals (Sweden)

Choirul Amin

2017-07-01

Full Text Available Since people living in a karst area periodically face a crisis due to a lack of fresh water, it is necessary to re-evaluate the ability to use water resources. An appropriate and effective management is required to use available water resource sustainably. We describe a management process of exploring underground river in karst region as water resources. The activities completed included four phases, namely exploration, pre-lifting activities, the water lifting and post-lifting activities. The exploration phase included speleological surveys and data collection for the cave mouth using remote sensing instrument. The pre-lifting was done to prepare various requirements before the lifting process was completed. The water lifting phase consisted of the construction of an underground river dam, the installation of submersible pumps, the construction of reservoirs and the installation of piping to connect to the public hydrant. The post-lifting phase was mainly conducted to organise water distribution evenly. This management model was evidenced to successfully overcome drought in Pucung village by providing fresh water to the local community. Moreover, this model promoted residents’ cost savings by reducing their expenses for buying water from IDR 50,000/m3 to IDR 3,500/m3 (1,300 percent.

Cosmic Ray Astrophysics using The High Altitude Water Cherenkov (HAWC Observatory in México

Directory of Open Access Journals (Sweden)

de la Fuente Eduardo

2017-01-01

Full Text Available The High-Altitude Water Cherenkov (HAWC TeV gamma–ray Observatory in México is ready to search and study gamma-ray emission regions, extremely high-energy cosmic-ray sources, and to identify transient phenomena. With a better Gamma/Hadron rejection method than other similar experiments, it will play a key role in triggering multi–wavelength and multi–messenger studies of active galaxies (AGN, gamma-ray bursts (GRB, supernova remnants (SNR, pulsar wind nebulae (PWN, Galactic Plane Sources, and Cosmic Ray Anisotropies. It has an instantaneous field-of-view of ∼2 str, equivalent to 15% of the whole sky and continuous operation (24 hours per day. The results obtained by HAWC–111 (111 detectors in operation were presented on the proceedings of the International Cosmic Ray Conference 2015 and in [1]. The results obtained by HAWC–300 (full operation are now under analysis and will be published in forthcoming papers starting in 2017 (see preliminary results on http://www.hawc-observatory.org/news/. Here we present the HAWC contributions on cosmic ray astrophysics via anisotropies studies, summarizing the HAWC detector and its upgrading by the installation of “outriggers”.

Indian primacy procedures handbook for the public water system supervision (PWSS) program and the underground injection control (UIC) program

International Nuclear Information System (INIS)

1993-03-01

The handbook defines primacy, the responsibilities of primacy, primacy's advantages and limitations, and how to seek primacy. Primacy is a provision in the 1986 Amendments to the Safe Drinking Water Act (SDWA). It allows Indian Tribes the opportunity to assume principal responsibility in the enforcement of public drinking water and/or underground injection control (UIC) regulations within the Indian Tribe's jurisdiction. To attain primacy a Tribe must have drinking water and underground injection control regulations which are at least as strict as EPA regulations, and must have an independent agency or organization within the Tribal government that has the power to enforce its regulations

Instrumentation development for an array of water Cherenkov detectors for extensive air shower experiments

Science.gov (United States)

Sheidaei, F.; Bahmanabadi, M.; Keivani, A.; Samimi, J.

2009-11-01

A new small array of Cherenkov detectors has been deployed in Tehran, 1200 m above sea level. This array contains four tanks of distilled water with a diameter of 64 cm and a height of 130 cm. The effective area of each tank is about 1382 cm2. They are used to detect air showers and to record the arrival time of the secondary particles. We have collected about 640 000 extensive air showers (EAS) in 8298 h of observation time from November 2006 to October 2007. The distribution of air showers in zenith and azimuth angles has been studied and a cosnθ distribution with n = 6.02 ± 0.01 was obtained for the zenith angle distribution. An asymmetry has been observed in the azimuthal distribution of EAS of cosmic rays due to geomagnetic field. The first and second amplitudes of the asymmetry are AI = 0.183 ± 0.001 and AII = 0.038 ± 0.001. Since the recent results are in good agreement with our previous results of scintillation detectors, and tanks of distilled water are cheaper, we prefer to use them instead of scintillators in a future larger array. By simulation, we have improved the size of the detectors to yield the highest efficiency. The best dimensions for each tank with a photomultiplier tube in the center of its lid are 40 cm in diameter and 60 cm in height.

The first GCT camera for the Cherenkov Telescope Array

CERN Document Server

De Franco, A.; Allan, D.; Armstrong, T.; Ashton, T.; Balzer, A.; Berge, D.; Bose, R.; Brown, A.M.; Buckley, J.; Chadwick, P.M.; Cooke, P.; Cotter, G.; Daniel, M.K.; Funk, S.; Greenshaw, T.; Hinton, J.; Kraus, M.; Lapington, J.; Molyneux, P.; Moore, P.; Nolan, S.; Okumura, A.; Ross, D.; Rulten, C.; Schmoll, J.; Schoorlemmer, H.; Stephan, M.; Sutcliffe, P.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Varner, G.; Watson, J.; Zink, A.

2015-01-01

The Gamma Cherenkov Telescope (GCT) is proposed to be part of the Small Size Telescope (SST) array of the Cherenkov Telescope Array (CTA). The GCT dual-mirror optical design allows the use of a compact camera of diameter roughly 0.4 m. The curved focal plane is equipped with 2048 pixels of ~0.2{\\deg} angular size, resulting in a field of view of ~9{\\deg}. The GCT camera is designed to record the flashes of Cherenkov light from electromagnetic cascades, which last only a few tens of nanoseconds. Modules based on custom ASICs provide the required fast electronics, facilitating sampling and digitisation as well as first level of triggering. The first GCT camera prototype is currently being commissioned in the UK. On-telescope tests are planned later this year. Here we give a detailed description of the camera prototype and present recent progress with testing and commissioning.

Mirror position determination for the alignment of Cherenkov Telescopes

Energy Technology Data Exchange (ETDEWEB)

Adam, J. [TU Dortmund, Experimental Physics 5 Otto-Hahn-Str. 4, 44221 Dortmund (Germany); Ahnen, M.L. [ETH Zurich, Institute for Particle Physics Otto-Stern-Weg 5, 8093 Zurich (Switzerland); Baack, D. [TU Dortmund, Experimental Physics 5 Otto-Hahn-Str. 4, 44221 Dortmund (Germany); Balbo, M. [University of Geneva, ISDC Data Center for Astrophysics Chemin Ecogia 16, 1290 Versoix (Switzerland); Bergmann, M. [Universität Würzburg, Institute for Theoretical Physics and Astrophysics Emil-Fischer-Str. 31, 97074 Würzburg (Germany); Biland, A. [ETH Zurich, Institute for Particle Physics Otto-Stern-Weg 5, 8093 Zurich (Switzerland); Blank, M. [Universität Würzburg, Institute for Theoretical Physics and Astrophysics Emil-Fischer-Str. 31, 97074 Würzburg (Germany); Bretz, T. [ETH Zurich, Institute for Particle Physics Otto-Stern-Weg 5, 8093 Zurich (Switzerland); RWTH Aachen (Germany); Bruegge, K.A.; Buss, J. [TU Dortmund, Experimental Physics 5 Otto-Hahn-Str. 4, 44221 Dortmund (Germany); Dmytriiev, A. [University of Geneva, ISDC Data Center for Astrophysics Chemin Ecogia 16, 1290 Versoix (Switzerland); Domke, M. [TU Dortmund, Experimental Physics 5 Otto-Hahn-Str. 4, 44221 Dortmund (Germany); Dorner, D. [Universität Würzburg, Institute for Theoretical Physics and Astrophysics Emil-Fischer-Str. 31, 97074 Würzburg (Germany); FAU Erlangen (Germany); Einecke, S. [TU Dortmund, Experimental Physics 5 Otto-Hahn-Str. 4, 44221 Dortmund (Germany); Hempfling, C. [Universität Würzburg, Institute for Theoretical Physics and Astrophysics Emil-Fischer-Str. 31, 97074 Würzburg (Germany); and others

2017-07-11

Imaging Atmospheric Cherenkov Telescopes (IACTs) need imaging optics with large apertures to map the faint Cherenkov light emitted in extensive air showers onto their image sensors. Segmented reflectors fulfill these needs using mass produced and light weight mirror facets. However, as the overall image is the sum of the individual mirror facet images, alignment is important. Here we present a method to determine the mirror facet positions on a segmented reflector in a very direct way. Our method reconstructs the mirror facet positions from photographs and a laser distance meter measurement which goes from the center of the image sensor plane to the center of each mirror facet. We use our method to both align the mirror facet positions and to feed the measured positions into our IACT simulation. We demonstrate our implementation on the 4 m First Geiger-mode Avalanche Cherenkov Telescope (FACT).

The performance of silicon photomultipliers in Cherenkov TOF PET

International Nuclear Information System (INIS)

Dolenec, Rok; Korpar, Samo; Krizan, Peter; Pestotink, Rok

2015-01-01

In time-of-flight positron emission tomography (TOF PET) one of the main factors limiting the time resolution is the time evolution of the scintillation process. This can be avoided by using exclusively the Cherenkov light produced in a suitable material. Sub 100 ps FWHM timing has already been experimentally demonstrated but with a drawback of relatively low detection efficiency due to the photodetectors used. In this work silicon photomultipliers (SiPMs) are considered as a photodetector in Cherenkov TOF PET. The detection efficiency can be significantly improved by using SiPMs, however, at room temperature the SiPM dark counts introduce a significant source of fake coincidences. SiPM samples from different producers were tested in a simple back-to-back setup in combination with lead fluoride Cherenkov radiators. Results for coincidence timing, detection efficiency and effects of dark counts at different temperatures and SiPM overvoltages are presented.

Study of a Cherenkov TOF-PET module

Science.gov (United States)

Korpar, S.; Dolenec, R.; Križan, P.; Pestotnik, R.; Stanovnik, A.

2013-12-01

An apparatus, consisting of two PbF2 crystals, each coupled to a multichannel plate photomultiplier (MCP-PMT), has been constructed in order to measure the time-of-flight (TOF) of the two 511 keV annihilation photons produced in positron emission tomography (PET). Excellent timing is achieved by detecting the prompt Cherenkov photons produced by the absorption of the 511 keV gamma photons. The present work describes the measurement and image reconstruction of two 22Na point sources. In addition, the influence of the radiator thickness and the Cherenkov light absorption cut-off of the crystal on the efficiency and the timing resolution have been studied by Monte Carlo simulation.

Research on mutual influence of Cherenkov-type probes within the ISTTOK tokamak chamber

Energy Technology Data Exchange (ETDEWEB)

Jakubowski, L., E-mail: lech.jakubowski@ncbj.gov.pl [National Centre for Nuclear Research (NCBJ), 05-400 Otwock (Poland); Plyusnin, V.V. [Association Euratom/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Malinowski, K.; Sadowski, M.J.; Zebrowski, J.; Rabinski, M. [National Centre for Nuclear Research (NCBJ), 05-400 Otwock (Poland); Fernandes, H.; Silva, C.; Figueiredo, H. [Association Euratom/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Jakubowski, M.J. [National Centre for Nuclear Research (NCBJ), 05-400 Otwock (Poland)

2014-12-11

The paper describes an influence of a Cherenkov-type probe, which is used for measurements of fast electron streams inside the ISTTOK chamber, on other probes and behaviour of a plasma ring. The reported study shows that such a probe situated near the plasma column has a strong influence on signals from another Cherenkov probe, and can cause a considerable reduction of electron-induced signals. This effect does not depend on positions of the probes in relation to the limiter. Measurements of hard X-ray (HXR) emission show that the deeply immersed Cherenkov probe can also influence on the limiter . Under specific experimental conditions such a Cherenkov probe can play the role of a new limiter and change the plasma configuration.

First studies of 500-nm Cherenkov radiation from 255-MeV electrons in a diamond crystal

Energy Technology Data Exchange (ETDEWEB)

Takabayashi, Y., E-mail: takabayashi@saga-ls.jp [SAGA Light Source, 8-7 Yayoigaoka, Tosu, Saga 841-0005 (Japan); Fiks, E.I. [National Research Tomsk Polytechnic University, 634050 Tomsk (Russian Federation); Pivovarov, Yu.L. [National Research Tomsk Polytechnic University, 634050 Tomsk (Russian Federation); National Research Tomsk State University, 634050 Tomsk (Russian Federation)

2015-06-12

The first experiment on Cherenkov light from 255-MeV electrons passing through a 50-μm-thick diamond crystal in a special geometry allowing extraction of 500-nm Cherenkov light at a right angle with respect to the electron beam direction has been performed at the injector linac of SAGA Light Source accelerator facility. The dependence of 500-nm Cherenkov light intensity (separated by a band-pass filter) on the crystal rotation angle was measured by a CCD detector. The experimentally obtained rocking curve with an intense maximum is theoretically explained as the projector effect of Cherenkov light deflected by the exit surface of the crystal. The width of the rocking curve is explained by the convolution of the standard Tamm–Frank angular distribution of Cherenkov radiation with chromatic aberration, the multiple scattering of electrons in a crystal, and initial electron beam angular divergence. In addition, it is found that the Cherenkov light intensity did not change under the (220) planar channeling condition, which is consistent with a recent theory. - Highlights: • Cherenkov light from 255-MeV electrons in a diamond crystal has been investigated. • The Cherenkov light from channeled electrons has been observed for the first time. • The experimental results are in good agreement with theory.

Impact of climate change on the stability of underground cavities. Status of knowledge. Investigation report

International Nuclear Information System (INIS)

Didier, C.; Al Heib, M.; Gombert, P.; Charmoille, A.; Watelet, Jean-Marc

2010-01-01

After having described the impact of global warming on climate parameters (possible climate evolution, impact on temperatures and precipitations in France) and presented underground cavities in France (nature and localisation, expected instability), this report discusses the impact of climate change on underground waters: impact on water cycle, on underground water level variation, and on the power of dissolution by underground waters. Then, it more particularly addresses the impact of water on underground cavity stability: impact of water on the behaviour of underground works, examples (iron mines, water sheet rising, quarry collapsing, and so on, in France, Belgium and USA), development of natural cavities. It finally outlines the perspectives, knowledge gaps, and required researches

76 FR 51970 - Agency Information Collection Activities; Proposed Collection; Comment Request; Underground...

Science.gov (United States)

2011-08-19

... Underground Injection Control (UIC) Program under the Safe Drinking Water Act established a Federal and State... Activities; Proposed Collection; Comment Request; Underground Injection Control (UIC) Program AGENCY... Water Protection Division/Underground Injection Control Program, Mailcode: 4606M, Environmental...

Measurement of aerogel performance for ring image Cherenkov detector of HERMES

International Nuclear Information System (INIS)

Kanesaka, Jiro; Zhang Linfeng; Sato, Fumiko; Suetsugu, Kentaro; Sakami, Yasuhiro; Shibata, Toshiaki

1999-01-01

The first experiment of ring image Cherenkov detector (RICH) used aerogel in the world was reported in this paper. We built RICH using aerogel as illuminant for HERMES. The refractive index and size of all aerogel tiles were measured in order to select them for construction of RICH. The select conditions of tile were 113.1 -4 , the dispersion of refractive index of aerogel tile, which condition was fitted to the accuracy of Cherenkov light emission angle of RICH. The mean thickness, transmission and reflection of tile, the thickness of corner of tile (thickness of surface), the refractive index dependence on position and temperature were measured. The effect of thickness of tile on the shift of Cherenkov emission angle was 6.1% the maximum value per one tile and 0.18% mean value of center. The effect of position dependence of refractive index on the Cherenkov light emission angle was agreed with the effect of dispersion of thickness of tile. The transmission and reflection of tile were almost same as the theoretical value. (S.Y.)

FACT. Normalized and asynchronous mirror alignment for Cherenkov telescopes

Energy Technology Data Exchange (ETDEWEB)

Mueller, Sebastian Achim [ETH Zurich (Switzerland); Buss, Jens [TU Dortmund (Germany)

2016-07-01

Imaging Atmospheric Cherenkov Telescopes (IACTs) need fast and large imaging optics to map the faint Cherenkov light emitted in cosmic ray air showers onto their image sensors. Segmented reflectors are inexpensive, lightweight and offer good image quality. However, alignment of the mirror facets remains a challenge. A good alignment is crucial in IACT observations to separate gamma rays from hadronic cosmic rays. We present a star tracking alignment method which is not restricted to clear nights. It normalizes the mirror facet reflections to be independent of the reference star or the cloud coverage. It records asynchronously of the telescope drive which makes the method easy to integrate in existing telescopes. It can be combined with remote facet actuation, but it does not need one to work. Furthermore, it can reconstruct all individual mirror facet point spread functions. We present the method and alignment results on the First Geiger-mode Photo Diode Avalanche Cherenkov Telescope (FACT) on the Canary Island of La Palma, Spain.

High water level installation of monitoring wells for underground storage tanks

International Nuclear Information System (INIS)

Treadway, C.

1990-01-01

This paper briefly describes a common monitoring well installation design for shallow ground water contamination resulting from leaky underground storage tanks. The paper describes drilling techniques used in unconsolidated Florida aquifers using hollow-stem augers. It describes methods for the prevention of heaving sands and sand-locking problems. It then goes on to describe the proper well casing placement and sealing techniques using neat cements. The proper sell screen level is also discussed to maximize the detection of floating hydrocarbons

An anti-Cherenkov photomultiplier tube

International Nuclear Information System (INIS)

Selove, W.; Cormell, L.R.; Dris, M.; Kononenko, W.; Robinson, B.; Yost, B.T.

1982-01-01

We have designed a special photomultiplier tube (PMT), with very much reduced sensitivity to Cherenkov light produced in the end window. These PMTs have been produced for us by EMI, and have been used in a modular calorimeter array. The design eliminates a 'hot-spot' problem which was of intolerable magnitude in our application. (orig.)

Camera selection for real-time in vivo radiation treatment verification systems using Cherenkov imaging.

Science.gov (United States)

Andreozzi, Jacqueline M; Zhang, Rongxiao; Glaser, Adam K; Jarvis, Lesley A; Pogue, Brian W; Gladstone, David J

2015-02-01

To identify achievable camera performance and hardware needs in a clinical Cherenkov imaging system for real-time, in vivo monitoring of the surface beam profile on patients, as novel visual information, documentation, and possible treatment verification for clinicians. Complementary metal-oxide-semiconductor (CMOS), charge-coupled device (CCD), intensified charge-coupled device (ICCD), and electron multiplying-intensified charge coupled device (EM-ICCD) cameras were investigated to determine Cherenkov imaging performance in a clinical radiotherapy setting, with one emphasis on the maximum supportable frame rate. Where possible, the image intensifier was synchronized using a pulse signal from the Linac in order to image with room lighting conditions comparable to patient treatment scenarios. A solid water phantom irradiated with a 6 MV photon beam was imaged by the cameras to evaluate the maximum frame rate for adequate Cherenkov detection. Adequate detection was defined as an average electron count in the background-subtracted Cherenkov image region of interest in excess of 0.5% (327 counts) of the 16-bit maximum electron count value. Additionally, an ICCD and an EM-ICCD were each used clinically to image two patients undergoing whole-breast radiotherapy to compare clinical advantages and limitations of each system. Intensifier-coupled cameras were required for imaging Cherenkov emission on the phantom surface with ambient room lighting; standalone CMOS and CCD cameras were not viable. The EM-ICCD was able to collect images from a single Linac pulse delivering less than 0.05 cGy of dose at 30 frames/s (fps) and pixel resolution of 512 × 512, compared to an ICCD which was limited to 4.7 fps at 1024 × 1024 resolution. An intensifier with higher quantum efficiency at the entrance photocathode in the red wavelengths [30% quantum efficiency (QE) vs previous 19%] promises at least 8.6 fps at a resolution of 1024 × 1024 and lower monetary cost than the EM-ICCD. The

Radionuclide concentrations in underground waters of Mururoa and Fangataufa Atolls.

Science.gov (United States)

Mulsow, S; Coquery, M; Dovlete, C; Gastaud, J; Ikeuchi, Y; Pham, M K; Povinec, P P

1999-09-30

In 1997 an expedition to Mururoa and Fangataufa Atolls was carried out to sample underground waters from cavity-chimneys and carbonate monitoring wells. The aim of this study was to determine the prevailing concentration and distribution status of radionuclides. Elemental analysis of interstitial waters was carried out in the water fraction as well as in particles collected at 11 underground monitoring wells. 238Pu, 239,240Pu, 241Am, 137Cs, 90Sr, 3H, 125Sb, 155Eu and 60Co were analyzed in both fractions by alpha-, beta- and gamma-spectrometry. Measurements showed that at 60% of the sites, pH and Eh seemed to be related to tidal cycles; in contrast HTO was constant during the sampling time. Interstitial waters from carbonates and transition zones shared similar chemical composition that were not different from that of the surrounding seawater. Waters collected from basalt cavities left after nuclear tests, (Aristee and Ceto) have a different chemical signature characterized by a deficiency in Mg, K and SO4 as well as enrichment in Sr, Si, Al and Cl compared to the rest of the stations. Radionuclide concentrations present in both, water and particulate fractions, were significantly higher at Ceto and Aristee than at any other monitoring wells, except for Fuseau and Mitre monitoring wells (Fangataufa) where values similar to Ceto were found (e.g. 239,240Pu: > 20 mBq g-1). Considering that Pu isotopes showed high Kd values compared to non-sorbing radionuclides such as 3H, 90Sr and 137Cs it is very unlikely that migration from cavities to monitoring wells accounts for the concentration of Pu isotopes and Am at Fuseau 30 and Mitre 27. Perhaps the contact of lagoon waters with the well before sealing could be a possible source of the transuranics found at these sites. The 238Pu/239,240Pu ratios measured in the particles were similar to that of the lagoon (0.38), thus supporting this hypothesis. The fact that transuranics were found only in the particle fraction, in the

The first telescope of the HEGRA air Cherenkov imaging telescope array

International Nuclear Information System (INIS)

Mirzoyan, R.; Kankanian, R.; Krennrich, F.; Mueller, N.; Sander, H.; Sawallisch, P.; Aharonian, F.; Akhperjanian, A.; Beglarian, A.; Fernandez, J.; Fonseca, V.; Grewe, W.; Heusler, A.; Konopelko, A.K.; Lorenz, E.; Merck, M.; Plyasheshnikov, A.V.; Renker, D.; Samorski, M.; Sauerland, K.; Smarsch, E.; Stamm, W.; Ulrich, M.; Wiedner, C.A.; Wirth, H.

1994-01-01

In search of VHE γ ray emission from cosmic point sources a system of imaging Cherenkov telescopes is constructed at present on the Canarian island of La Palma; the first telescope has been operational since 1992. The Cherenkov light from air shower particles is collected by a 5 m 2 reflector. The camera at the focus contains 37 photomultipliers which sample the images of the Cherenkov flashes. The subsequent image analysis allows the discrimination of γ ray induced events from the much more abundant charged cosmic ray induced showers. The telescope has an effective energy threshold for γ showers of about 1.5 TeV. During the first year of operation a signal from the Crab nebula was detected. ((orig.))

Study of TeV range cosmic ray detection with Cherenkov imaging techniques

International Nuclear Information System (INIS)

Ansari, R.; Gaillard, J.M.; Parrour, G.

1992-03-01

The Monte Carlo study of cosmic ray detection in the TeV energy range has been triggered by the authors' interest in the ARTEMIS (Antimatter Research Through the Earth Moon Ion Spectrometer) proposal. The properties of cosmic ray showers detected by Cherenkov imaging in the visible domain are studied. The detection sensitivity and the accuracy of the reconstruction of the parent particle direction using Cherenkov imaging are discussed. The backbone of the study is the atmospheric shower Monte Carlo generator developed by A.M. Hillas. A comparison between nucleon and photon induced showers of Cherenkov detection is also included. (R.P.) 14 refs., 48 figs., 3 tabs

First observations of tritium in ground water outside chimneys of underground nuclear explosions, Yucca Flat, Nevada Test Site

International Nuclear Information System (INIS)

Crow, N.B.

1976-01-01

Abnormal levels of radionuclides had not been detected in ground water at the Nevada Test Site beyond the immediate vicinity of underground nuclear explosions until April 1974, when above-background tritium activity levels were detected in ground-water inflow from the tuff beneath Yucca Flat to an emplacement chamber being mined in hole U2aw in the east-central part of Area 2. No other radionuclides were detected in a sample of water from the chamber. In comparison with the amount of tritium estimated to be present in the ground water in nearby nuclear chimneys, the activity level at U2aw is very low. To put the tritium activity levels at U2aw into proper perspective, the maximum tritium activity level observed was significantly less than the maximum permissible concentration (MPC) for a restricted area, though from mid-April 1974 until the emplacement chamber was expended in September 1974, the tritium activity exceeded the MPC for the general public. Above-background tritium activity was also detected in ground water from the adjacent exploratory hole, Ue2aw. The nearest underground nuclear explosion detonated beneath the water table, believed to be the source of the tritium observed, is Commodore (U2am), located 465 m southeast of the emplacement chamber in U2aw. Commodore was detonated in May 1967. In May 1975, tritium activity May significantly higher than regional background. was detected in ground water from hole Ue2ar, 980 m south of the emplacement chamber in U2aw and 361 m from a second underground nuclear explosion, Agile (U2v), also detonated below the water table, in February 1967. This paper describes these occurrences of tritium in the ground water. A mechanism to account for the movement of tritium is postulated

Investigating the Cherenkov light lateral distribution function for primary proton and iron nuclei in extensive air showers

International Nuclear Information System (INIS)

Al-Rubaiee, A.A.; Hashim, U.; Al-Douri, Y.

2015-01-01

The lateral distribution function (LDF) of Cherenkov radiation in extensive air showers (EAS) was simulated by CORSIKA program for the conditions of Yakutsk Cherenkov array at high energy range (10 13 -10 16 eV) for two primary particles (p and Fe) for different zenith angles. Using Breit-Wigner function for analyzing Cherenkov light LDF, a parameterization of Cherenkov light LDF was reconstructed by depending on CORSIKA simulation as a function of primary energy. The comparison between the estimated Cherenkov light LDF and the LDF that was measured on the Yakutsk EAS array gives the ability of particle identification that initiated the shower and determination of particle's energy around the knee region. The extrapolation of approximated Cherenkov light LDF for energies 20 and 30 PeV was obtained for primary particles (p and Fe)

Concept of underground nuclear power plant

International Nuclear Information System (INIS)

Onishi, Sotoaki

1976-01-01

The concept of constructing nuclear power plants on the sea or underground as the future sitting is based on moving the present power plants on the ground with actual results to the sea or underground without changing the design. The underground nuclear power plants have many similar points to underground hydro-electric power stations with many achievements in the construction viewpoint, though they have their proper difficult problems. Of course, it requires to excavate larger underground caves than the case of underground hydro-electric power plants. The maximum dimensions of the caves have been determined through experience in practice. Therefore the developments of design theory and construction technique are desirable in this field. In discussing underground construction, two evaluating methods are considered for the shielding effect of base rocks. The minimum vertical distance up to ground surface from the center of the cave differs depending upon the in-cave pressure, and the conditions of base rock, soil and underground water in case of the accident assumed in the design, and is approximately 60m, if the cave is assumed to be an indefinite cylindrical shape, by the safer side calculation in the above two evaluations. (Wakatsuki, Y.)

Cherenkov-type diagnostics of fast electrons beams escaping from MCF facilities

Energy Technology Data Exchange (ETDEWEB)

Jakubowski, L.; Malinowski, K.; Mirowski, R.; Rabinski, M.; Sadowski, M.J.; Zebrowski, J. [Institute for Nuclear Studies - IPJ, 05-400 Otwock-Swierk (Poland)

2011-07-01

The paper presents the feasibility study, the measuring system and the first experimental results of a new method developed for direct detection of high-energy (super-thermal, ripple-born and runaway) electrons generated in magnetic confinement fusion (MCF) facilities. The technique in question is based on registration of the Cherenkov radiation, emitted by energetic electrons, moving through a transparent medium (radiator) with a velocity higher than the velocity of light in this material. The main aim of our studies was to develop a diagnostic technique applicable for measurements of fast electron beams within MCF devices. The IPJ team proposed Cherenkov-type probes because of their high spatial- and temporal-resolutions. The most important results of applications of the presented Cherenkov-type diagnostics have proved that the one- and four-channel versions of the detecting head are useful for studies of the fast (ripple-born and runaway) electrons in different MCF experiments. Experience collected during the described studies allows to introduce some changes in the radiator configuration and to modify the Cherenkov probe design. This document is composed of a paper followed by a poster

Stability numerical analysis of soil cave in karst area to drawdown of underground water level

Science.gov (United States)

Mo, Yizheng; Xiao, Rencheng; Deng, Zongwei

2018-05-01

With the underground water level falling, the reliable estimates of the stability and deformation characteristics of soil caves in karst region area are required for analysis used for engineering design. Aimed at this goal, combined with practical engineering and field geotechnical test, detail analysis on vertical maximum displacement of top, vertical maximum displacement of surface, maximum principal stress and maximum shear stress were conducted by finite element software, with an emphasis on two varying factors: the size and the depth of soil cave. The calculations on the soil cave show that, its stability of soil cave is affected by both the size and depth, and only when extending a certain limit, the collapse occurred along with the falling of underground water; Additionally, its maximum shear stress is in arch toes, and its deformation curve trend of maximum displacement is similar to the maximum shear stress, which further verified that the collapse of soil cave was mainly due to shear-failure.

The water Cherenkov detector array for studies of cosmic rays at the University of Puebla

International Nuclear Information System (INIS)

Cotzomi, J.; Moreno, E.; Murrieta, T.; Palma, B.; Perez, E.; Salazar, H.; Villasenor, L.

2005-01-01

We describe the design and performance of a hybrid extensive air shower detector array built on the Campus of the University of Puebla (19 - bar N, 90 - bar W, 800g/cm 2 ) to measure the energy, arrival direction and composition of primary cosmic rays with energies around 1PeV, i.e., around the knee of the cosmic ray spectrum. The array consists of 3 water Cherenkov detectors of 1.86m 2 cross-section and 12 liquid scintillator detectors of 1m 2 distributed in a square grid with a detector spacing of 20m over an area of 4000m 2 . We discuss the calibration and stability of the array for both sets of detectors and report on preliminary measurements and reconstruction of the lateral distributions for the electromagnetic (EM) and muonic components of extensive air showers. We also discuss how the hybrid character of the array can be used to measure mass composition of the primary cosmic rays by estimating the relative contents of muons with respect to the EM component of extensive air showers. This facility is also used to train students interested in the field of cosmic rays

Measurable difference in Cherenkov light between gamma and hadron induced EAS

Energy Technology Data Exchange (ETDEWEB)

Cabot, H.; Meynadier, Ch. [Universite de Perpignan, Groupe de Physique Fondamentale, Perpignan (France); Sobczynska, D. [Experimental Physics Department, University of Lodz, Lodz (Poland); Szabelska, B. [Soltan Institute for Nuclear Studies, Lodz (Poland); Szabelski, J. [Universite de Perpignan, Groupe de Physique Fondamentale, Perpignan (France)]|[Soltan Institute for Nuclear Studies, Lodz (Poland); Wibig, T. [Experimental Physics Department, University of Lodz, Lodz (Poland)

1997-12-31

We describe the possibly measurable difference in the Cherenkov light component of EAS induced by en electromagnetic particle (i.e. e{sup +}, e{sup -} or {gamma}) and induced by a hadron (i.e. proton or heavier nuclei) in TeV range. The method can be applied in experiments which use wavefront sampling method of EAS Cherenkov light detection (e.g. THEMISTOCLE, ASGAT). (author) 16 refs, 9 figs

Cherenkov radiation in a plasma-filled, dielectric coaxial waveguide

International Nuclear Information System (INIS)

Wu Jianqiang

2004-01-01

Using the self-consistent linear field theory, Cherenkov radiation excitated by the beam-wave interaction of a thin annular relativistic electron beam in a plasma-filled, dielectric coaxial cylindrical waveguide was analyzed. The dispersion equation of the interaction, the synchronized condition and the wave growth rate were derived. The energy exchange between the wave and the electron beam in the presence of background plasma was discussed, and the effects of plasma density on the dispersion characteristics, the wave growth rate and the beam-wave energy exchange were calculated and discussed. It was clear that the Cherenkov radiation results from the coupling between the slow TM mode propagated along the waveguide and the negative-energy space-charge mode propagated along the beam, and the coupling strength is proportional to the beam density. It was theoretically demonstrated that due to the background plasma, the plasma-filled coaxial cylindrical Cherenkov maser could operate at higher frequency, get higher wave growth rate, or have higher beam current at the same operating frequency, leading to higher microwave output power. (authors)

SU-G-IeP4-06: Feasibility of External Beam Treatment Field Verification Using Cherenkov Imaging

Energy Technology Data Exchange (ETDEWEB)

Black, P; Na, Y; Wuu, C [Columbia University, New York, NY (United States)

2016-06-15

Purpose: Cherenkov light emission has been shown to correlate with ionizing radiation (IR) dose delivery in solid tissue. In order to properly correlate Cherenkov light images with real time dose delivery in a patient, we must account for geometric and intensity distortions arising from observation angle, as well as the effect of monitor units (MU) and field size on Cherenkov light emission. To test the feasibility of treatment field verification, we first focused on Cherenkov light emission efficiency based on MU and known field size (FS). Methods: Cherenkov light emission was captured using a PI-MAX4 intensified charge coupled device(ICCD) system (Princeton Instruments), positioned at a fixed angle of 40° relative to the beam central axis. A Varian TrueBeam linear accelerator (linac) was operated at 6MV and 600MU/min to deliver an Anterior-Posterior beam to a 5cm thick block phantom positioned at 100cm Source-to-Surface-Distance(SSD). FS of 10×10, 5×5, and 2×2cm{sup 2} were used. Before beam delivery projected light field images were acquired, ensuring that geometric distortions were consistent when measuring Cherenkov field discrepancies. Cherenkov image acquisition was triggered by linac target current. 500 frames were acquired for each FS. Composite images were created through summation of frames and background subtraction. MU per image was calculated based on linac pulse delay of 2.8ms. Cherenkov and projected light FS were evaluated using ImageJ software. Results: Mean Cherenkov FS discrepancies compared to light field were <0.5cm for 5.6, 2.8, and 8.6 MU for 10×10, 5×5, and 2×2cm{sup 2} FS, respectably. Discrepancies were reduced with increasing field size and MU. We predict a minimum of 100 frames is needed for reliable confirmation of delivered FS. Conclusion: Current discrepancies in Cherenkov field sizes are within a usable range to confirm treatment delivery in standard and respiratory gated clinical scenarios at MU levels appropriate to

Multielement neutron activation analysis of underground water samples

International Nuclear Information System (INIS)

Kusaka, Yuzuru; Tsuji, Haruo; Fujimoto, Yuzo; Ishida, Keiko; Mamuro, Tetsuo.

1980-01-01

An instrumental neutron activation analysis by gamma-ray spectrometry with high resolution and large volume Ge (Li) detectors followed by data processing with an electronic computer was applied to the multielemental analysis to elucidate the chemical qualities of the underground water which has been widely used in the sake brewing industries in Mikage, Uozaki and Nishinomiya districts, called as miyamizu. The evaporated residues of the water samples were subjected to the neutron irradiations in reactor for 1 min at a thermal flux of 1.5 x 10 12 n.cm -2 .sec -1 and for 30 hrs at a thermal flux of 9.3 x 10 11 n.cm -2 .sec -1 or for 5 hrs at a thermal flux of 3.9 x 10 12 n.cm -2 .sec -1 . Thus, 11 elements in the former short irradiation and 38 elements in the latter two kinds of long irradiation can be analyzed. Conventional chemical analysis including atomic absorption method and others are also applied on the same samples, and putting the all results together, some considerations concerning the geochemical meaning of the analytical values are made. (author)

Data of groundwater from boreholes, river water and precipitation for the Horonobe Underground Research Laboratory project. 2011-2010

Energy Technology Data Exchange (ETDEWEB)

Amano, Yuki; Yamamoto, Yoichi; Nanjyo, Isao; Murakami, Hiroaki; Yokota, Hideharu; Yamazaki, Masanori; Iwatsuki, Teruki [Japan Atomic Energy Agency, Geological Isolation Research and Development Directorate, Horonobe, Hokkaido (Japan); Kunimaru, Takanori [Japan Atomic Energy Agency, Geological Isolation Research and Development Directorate, Mizunami, Gifu (Japan); Oyama, Takahiro [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

2012-02-15

In the Horonobe Underground Research Laboratory (URL) Project, groundwater from boreholes, river water and precipitation have been analyzed for the environmental monitoring since the fiscal year 2001. This report shows the data set of water chemistry since the fiscal year 2001 to the fiscal year 2010. (author)

Data of groundwater from boreholes, river water and precipitation for the Horonobe Underground Research Laboratory project. 2011-2010

International Nuclear Information System (INIS)

Amano, Yuki; Yamamoto, Yoichi; Nanjyo, Isao; Murakami, Hiroaki; Yokota, Hideharu; Yamazaki, Masanori; Iwatsuki, Teruki; Kunimaru, Takanori; Oyama, Takahiro

2012-02-01

In the Horonobe Underground Research Laboratory (URL) Project, groundwater from boreholes, river water and precipitation have been analyzed for the environmental monitoring since the fiscal year 2001. This report shows the data set of water chemistry since the fiscal year 2001 to the fiscal year 2010. (author)

Extensive air showers and diffused Cherenkov light detection: The ULTRA experiment

International Nuclear Information System (INIS)

Agnetta, G.; Assis, P.; Biondo, B.

2007-01-01

The Uv Light Transmission and Reflection in the Atmosphere (ULTRA) experiment has been designed to provide quantitative measurements of the backscattered Cherenkov signal associated to the Extensive Air Showers (EAS) at the impact point on the Earth surface. The knowledge of such information will test the possibility to detect the diffused Cherenkov light spot from space within the Ultra high-energy cosmic ray observation. The Cherenkov signal is necessary to give an absolute reference for the track, allowing the measurement of the shower maximum and easing the separation between neutrino and hadronic showers. In this paper we discuss the experimental set-up with detailed information on the detection method; the in situ and laboratory calibrations; the simulation of the expected detector response and finally the preliminary results on the detector performance

Conceptual history of the Vavilov-Cherenkov radiation

International Nuclear Information System (INIS)

Frank, I.M.

1984-01-01

The evolution of ideas on the nature of the Vavilov-Cherenkov radiation is discussed. The period between Vavilov's ideas, advanced in 1934, and the formulation of a quantitative theory of the phenomenon in 1937 is surveyed

Contamination of surface and underground waters owing to the disaster of the Sasa mine tailing pond

OpenAIRE

Mircovski, Vojo; Spasovski, Orce

2003-01-01

The uncontrolled run off of flotation waste from the Sasa Mine causes contamination of the flows of the Rivers Kamenicka and Bregalnica as well as the water of Kalimanci Lake and further afield. Boundary, fracture and karst type of aquifers formed depending on the structural type of porosity along the marginal parts of the terrain. The aquifers are recharged mostly by the above mentioned rivers that results in contamination of their waters. Contamination of underground waters is particularly ...

G-APDs in Cherenkov astronomy: The FACT camera

International Nuclear Information System (INIS)

Krähenbühl, T.; Anderhub, H.; Backes, M.; Biland, A.; Boller, A.; Braun, I.; Bretz, T.; Commichau, V.; Djambazov, L.; Dorner, D.; Farnier, C.; Gendotti, A.; Grimm, O.; Gunten, H. von; Hildebrand, D.; Horisberger, U.; Huber, B.; Kim, K.-S.; Köhne, J.-H.; Krumm, B.

2012-01-01

Geiger-mode avalanche photodiodes (G-APD, SiPM) are a much discussed alternative to photomultiplier tubes in Cherenkov astronomy. The First G-APD Cherenkov Telescope (FACT) collaboration builds a camera based on a hexagonal array of 1440 G-APDs and has now finalized its construction phase. A light-collecting solid PMMA cone is glued to each G-APD to eliminate dead space between the G-APDs by increasing the active area, and to restrict the light collection angle of the sensor to the reflector area in order to reduce the amount of background light. The processing of the signals is integrated in the camera and includes the digitization using the domino ring sampling chip DRS4.

Theoretical study of Cherenkov radiation emission in anisotropic uniaxial crystals

Energy Technology Data Exchange (ETDEWEB)

Delbart, A; Derre, J

1996-04-01

A theoretical review of the Cherenkov radiation emission in uniaxial crystals is presented. The formalism of C. Muzicar in terms of energetic properties of the emitted waves are corrected. This formalism is used to simulate the Cherenkov radiation emission in a strongly birefringent sodium nitrate crystal (NaNO{sub 3}) and to investigate the consequences of the slight anisotropy of sapphire (Al{sub 2}O{sub 3}) on the design of the Optical Trigger. (author). 12 refs. Submitted to Physical Review, D (US).

Neutrino superluminality without Cherenkov-like processes in Finslerian special relativity

International Nuclear Information System (INIS)

Chang Zhe; Li Xin; Wang Sai

2012-01-01

Recently, Cohen and Glashow [A.G. Cohen, S.L. Glashow, Phys. Rev. Lett. 107 (2011) 181803] pointed out that the superluminal neutrinos reported by the OPERA would lose their energy rapidly via the Cherenkov-like process. The Cherenkov-like process for the superluminal particles would be forbidden if the principle of special relativity holds in any frame instead violated with a preferred frame. We have proposed that the Finslerian special relativity could account for the data of the neutrino superluminality ( (arXiv:1110.6673 [hep-ph])). The Finslerian special relativity preserves the principle of special relativity and involves a preferred direction while consists with the causality. In this Letter, we prove that the energy-momentum conservation is preserved and the energy-momentum is well defined in Finslerian special relativity. The Cherenkov-like process is forbidden in the Finslerian special relativity. Thus, the superluminal neutrinos would not lose energy in their distant propagation.

Characteristics of the forerunner field of underground water regime during the Tangshan earthquake and its focal evolution process

Energy Technology Data Exchange (ETDEWEB)

Wu, J.; Wang, Y.; Li, S.

1980-03-01

On the basis of data obtained from long-term observations of groundwater regime and taking the Tangshan earthquake as an example, the authors proposed first the principles and approaches for recognizing the precursory anomalies of earthquakes and classified the subsurface water regime into underground water, interlayer water and confined water. For the Tangshan earthquake, the forerunner field of underground water is characterized by its spatial distribution (limited to a certain quadrant), its stages of development in time and the synchronism of anomaly-changes during and after a shock. In addition, this study stresses the importance of the principles mentioned above in predicting the space, time, and magnitude of future earthquakes and discusses the relationship between the focal stress field and regional stress field and the indicator to distinguish them. It is suggested that the former develops progressively and its principal axis of compression stress changes in direction just before an earthquake, thus enabling us to divide the focal process into two basically different stages - brewing and originating stages.

Investigation of surface and underground waters about the Blayais nuclear site - 2010

International Nuclear Information System (INIS)

Migeon, A.; Bernollin, A.; Dunand, E.; Barbey, P.; Boilley, D.; Josset, M.

2011-01-01

This investigation aims at proposing a first assessment of the impact of releases on surface and underground waters around the Blayais nuclear power station, i.e. the assessment of the (mainly radiological) quality of waters. The report identifies the various pollution sources: old sources (like atmospheric nuclear tests, nuclear accidents), incidents in the Blayais station, and potential sources for the present contamination. Different radionuclides are searched like tritium, carbon 14, gamma radioactivity (from different elements), some beta emitters, radon as well as some chemicals related to the station activity (hydrazine, boric acid, EDTA, lithium, morpholine). Sampling sites are presented (estuary, canals, reservoirs). Radiological and chemical analysis are reported and commented. Significant presence of Tritium and Nickel-63 are noticed

The nonlinear CWFA [Cherenkov Wakefield Accelerator

International Nuclear Information System (INIS)

Schoessow, P.

1989-01-01

The possible use of nonlinear media to enhance the performance of the Cherenkov Wakefield Accelerator (CWFA) is considered. Numerical experiments have been performed using a new wakefield code which demonstrate larger gradients and transformer ratios in the nonlinear CWFA than are obtained in the linear case. 7 refs., 3 figs

In situ water and gas injection experiments performed in the Hades Underground Research Facility

Energy Technology Data Exchange (ETDEWEB)

Volckaert, G.; Ortiz, L.; Put, M. [SCK-CEN, Mol (Belgium). Geological Waste Disposal Unit

1995-12-31

The movement of water and gas through plastic clay is an important subject in the research at SCK-CEN on the possible disposal of high level radioactive waste in the Boom clay layer at Mol. Since the construction of the Hades underground research facility in 1983, SCK-CEN has developed and installed numerous piezometers for the geohydrologic characterization and for in situ radionuclide migration experiments. In situ gas and water injection experiments have been performed at two different locations in the underground laboratory. The first location is a multi filter piezometer installed vertically at the bottom of the shaft in 1986. The second location is a three dimensional configuration of four horizontal multi piezometers installed from the gallery. This piezometer configuration was designed for the MEGAS (Modelling and Experiments on GAS migration through argillaceous rocks) project and installed in 1992. It contains 29 filters at distances between 10 m and 15 m from the gallery in the clay. Gas injection experiments show that gas breakthrough occurs at a gas overpressure of about 0.6 MPa. The breakthrough occurs by the creation of gas pathways along the direction of lowest resistance i.e. the zone of low effective stress resulting from the drilling of the borehole. The water injections performed in a filter -- not used for gas injection -- show that the flow of water is also influenced by the mechanical stress conditions. Low effective stress leads to higher hydraulic conductivity. However, water overpressures up to 1.3 MPa did not cause hydrofracturing. Water injections performed in a filter previously used for gas injections, show that the occluded gas hinders the water flow and reduces the hydraulic conductivity by a factor two.

Calibration strategies for the Cherenkov Telescope Array

NARCIS (Netherlands)

Gaug, M.; Berge, D.; Daniel, M.; Doro, M.; Förster, A.; Hofmann, W.; Maccarone, M.C.; Parsons, D.; de los Reyes Lopez, R.; van Eldik, C.

2014-01-01

The Central Calibration Facilities workpackage of the Cherenkov Telescope Array (CTA) observatory for very high energy gamma ray astronomy defines the overall calibration strategy of the array, develops dedicated hardware and software for the overall array calibration and coordinates the calibration

Cherenkov angle and charge reconstruction with the RICH detector of the AMS experiment

CERN Document Server

Barão, F; Borges, J; Gonçalves, P; Pimenta, M; Pérez, I

2003-01-01

The Alpha Magnetic Spectrometer experiment to be installed on the International Space Station will be equipped with a proximity focusing Ring Imaging Cherenkov (RICH) detector, for measurements of particle electric charge and velocity. In this note, two possible methods for reconstructing the Cherenkov angle and the electric charge with the RICH are discussed. A Likelihood method for the Cherenkov angle reconstruction was applied leading to a velocity determination for protons with a resolution of around 0.1%. The existence of a large fraction of background photons which can vary from event to event implied a charge reconstruction method based on an overall efficiency estimation on an event-by-event basis.

Characterization of Multianode Photomultiplier Tubes for a Cherenkov Detector

Science.gov (United States)

Benninghoff, Morgen; Turisini, Matteo; Kim, Andrey; Benmokhtar, Fatiha; Kubarovsky, Valery; Duquesne University Collaboration; Jefferson Lab Collaboration

2017-09-01

In the Fall of 2017, Jefferson Lab's CLAS12 (CEBAF Large Acceptance Spectrometer) detector is expecting the addition of a RICH (ring imaging Cherenkov) detector which will allow enhanced particle identification in the momentum range of 3 to 8 GeV/c. RICH detectors measure the velocity of charged particles through the detection of produced Cherenkov radiation and the reconstruction of the angle of emission. The emitted Cherenkov photons are detected by a triangular-shaped grid of 391 multianode photomultiplier tubes (MAPMTs) made by Hamamatsu. The custom readout electronics consist of MAROC (multianode read out chip) boards controlled by FPGA (Field Programmable Gate Array) boards, and adapters used to connect the MAROC boards and MAPMTs. The focus of this project is the characterization of the MAPMTs with the new front end electronics. To perform these tests, a black box setup with a picosecond diode laser was constructed with low and high voltage supplies. A highly automated procedure was developed to acquire data at different combinations of high voltage values, light intensities and readout electronics settings. Future work involves using the collected data in calibration procedures and analyzing that data to resolve the best location for each MAPMT. SULI, NSF.

The Atmospheric Monitoring Strategy for the Cherenkov Telescope Array

Science.gov (United States)

Daniel, M. K.; CTA Consortium

2015-04-01

The Imaging Atmospheric Cherenkov Technique (IACT) is unusual in astronomy as the atmosphere actually forms an intrinsic part of the detector system, with telescopes indirectly detecting very high energy particles by the generation and transport of Cherenkov photons deep within the atmosphere. This means that accurate measurement, characterisation and monitoring of the atmosphere is at the very heart of successfully operating an IACT system. The Cherenkov Telescope Array (CTA) will be the next generation IACT observatory with an ambitious aim to improve the sensitivity of an order of magnitude over current facilities, along with corresponding improvements in angular and energy resolution and extended energy coverage, through an array of Large (23 m), Medium (12 m) and Small (4 m) sized telescopes spread over an area of order ~km2. Whole sky coverage will be achieved by operating at two sites: one in the northern hemisphere and one in the southern hemisphere. This proceedings will cover the characterisation of the candidate sites and the atmospheric calibration strategy. CTA will utilise a suite of instrumentation and analysis techniques for atmospheric modelling and monitoring regarding pointing forecasts, intelligent pointing selection for the observatory operations and for offline data correction.

A G-APD based Camera for Imaging Atmospheric Cherenkov Telescopes

International Nuclear Information System (INIS)

Anderhub, H.; Backes, M.; Biland, A.; Boller, A.; Braun, I.; Bretz, T.; Commichau, S.; Commichau, V.; Dorner, D.; Gendotti, A.; Grimm, O.; Gunten, H. von; Hildebrand, D.; Horisberger, U.; Koehne, J.-H.; Kraehenbuehl, T.; Kranich, D.; Lorenz, E.; Lustermann, W.; Mannheim, K.

2011-01-01

Imaging Atmospheric Cherenkov Telescopes (IACT) for Gamma-ray astronomy are presently using photomultiplier tubes as photo sensors. Geiger-mode avalanche photodiodes (G-APD) promise an improvement in sensitivity and, important for this application, ease of construction, operation and ruggedness. G-APDs have proven many of their features in the laboratory, but a qualified assessment of their performance in an IACT camera is best undertaken with a prototype. This paper describes the design and construction of a full-scale camera based on G-APDs realized within the FACT project (First G-APD Cherenkov Telescope).

Status and Results from DarkSide-50

OpenAIRE

Fan, Alden; Collaboration, for the DarkSide

2015-01-01

DarkSide-50 is the first physics detector of the DarkSide dark matter search program. The detector features a dual-phase underground-argon Time Projection Chamber (TPC) of 50 kg active mass surrounded by an organic liquid-scintillator neutron veto (30 tons) and a water-Cherenkov muon detector (1000 tons). The TPC is currently fully shielded and operating underground at Gran Sasso National Laboratory. A first run of 1422 kg-day exposure with atmospheric argon represents the most sensitive dark...

Determining origin of underground water in coal mines by means of natural isotopes and other geochemical parameters

Energy Technology Data Exchange (ETDEWEB)

Dolenec, T; Pezdic, J; Herlec, U; Kuscer, D; Mitrevski, G [Institut Josef Stefan, Ljubljana (Yugoslavia)

1989-07-01

Presents a preliminary report on origin of water in Slovenian brown coal mines. Water, coal and strata samples from the Hrastnik and Ojstro mines were analyzed for changes in chemical composition. Water samples were also analyzed for changes in isotopic composition and inorganic carbon and sulfur contents. Chemical, isotopic and geochemical techniques are described and results are presented with 21 diagrams. An attempt is made to explain the origin and age of water flowing from mine aquifers into mine rooms, and to explain the interdependence of surface and underground water flow. 10 refs.

Development of aerogel Cherenkov detectors at Novosibirsk

International Nuclear Information System (INIS)

Barnyakov, A.Yu.; Barnyakov, M.Yu.; Baehr, J.; Bellunato, T.; Beloborodov, K.I.; Bobrovnikov, V.S.; Buzykaev, A.R.; Calvi, M.; Danilyuk, A.F.; Djordjadze, V.; Golubev, V.B.; Kononov, S.A.; Kravchenko, E.A.; Lipka, D.; Matteuzzi, C.; Musy, M.; Onuchin, A.P.; Perego, D.; Rodiakin, V.A.; Savinov, G.A.; Serednyakov, S.I.; Shamov, A.G.; Stephan, F.; Tayursky, V.A.; Vorobiov, A.I.

2005-01-01

The development of aerogel Cherenkov counters with the light collection using a wavelength shifter is described. 80 counters of this type are working in the KEDR detector. A project of similar counters for the SND detector based on 'heavy' aerogel with n=1.13 has been developed. Aerogel with a refractive index of 1.006-1.13 and dimensions of blocks up to 200x200x50mm 3 is produced by the Novosibirsk group for use in Cherenkov counters of different types. The Novosibirsk group is participating in the development of LHCb RICH as well as a beam diagnostics for a photo-injector test facility at DESY-Zeuthen. Recently we started development of RICH based on focusing aerogel (FARICH) for the endcap of the SuperBaBar. For the first time in the world the focusing aerogel with layers of different refractive indices has been produced

Bypassing and tightening of an underground water retention system in permeable karst: case study of the hydropower plant (HPP) Bribin, Indonesia

Science.gov (United States)

Kudella, Peter; Loges, Iryna; Mutschler, Thomas; Eiche, Elisabeth; Ruppert, Julia; Neumann, Thomas

2016-09-01

In the framework of the Integrated Water Resources Management (IWRM) joint research project in the karst area of Gunung Kidul, Province of Yogyakarta Special Region on the Java Island, Indonesia, an underground hydropower driven water extraction facility in the cave "Bribin" was developed using pump-as-turbine-driven systems for freshwater supply of the rural area. As numerous other caves in the Gunung Kidul area, Bribin is part of a ramified system of all-season water-bearing subterraneous rivers and natural caves in karstic limestone. The elliptic cross section of the cave was completely closed with a concrete barrage, thus creating a year-round underground retention volume with an operational storage level of approx. 15 m. This contribution highlights the geotechnical and geohydraulic challenges handled within the sub-project "Short-time and long-time behaviour of karst rock surrounding pressure-bearing underground water-retaining structures". One key to the feasibility of an artificial water retention scheme in a natural cave is to ensure the mechanical stability of the cave roof and sidewalls. The necessary geotechnical investigations are described. Another key to the effectiveness of such a water retention concept is the control and minimization of "lost" seepage water bypassing the barrage structure through the karst rock mass. Measures to monitor and to explain the seepage phenomena are presented as well as grouting efforts to minimize them. The limitations of improving the overall tightness will be discussed. Interpretation includes the use of analytical and numerical methods.

[Assessment of Cyto- and Genotoxicity of Underground Waters from the Far Eastern Center on Radioactive Waste Treatment Site].

Science.gov (United States)

Oudalova, A A; Pyatkova, S V; Geras'kin, S A; Kiselev, S M; Akhromeev, S V

2016-01-01

This study has been completed in the frames of activities on the environment assessment in the vicinity of the Far Eastern center (FEC) on radioactive waste treatment (a branch of Fokino, Sysoev Bay). Underground waters collected at the FEC technical site were surveyed both with instrumental techniques and bioassays. Concentrations of some chemicals (ranged to the third hazard category) in the samples collected are over the permitted limits. Activities of 137Cs and 90Sr in waters amount up to 3.8 and 16.2 Bq/l, correspondingly. The integral pollution index is over 1 in all the samples and could amount up to 165. The Allium-test application allows the detection of the sample points where underground waters have an enhanced mutagenic potential. Dependencies between biological effects and pollution levels are analyzed. The findings obtained could be used for the monitoring optimized and decision making on rehabilitation measures to decrease negative influence of the enterprise on the environment.

Water quality changes of a closed underground coal mine in Korea.

Science.gov (United States)

Cheong, Young Wook; Yim, Gil-Jae; Ji, Sang Woo; Kang, Sang Soo; Skousen, Jeffery

2012-01-01

The objective of this study was to assess the changes in mine water quality as an underground mine flooded from July 2005 to October 2008. The effect of air injection with a blower into the water was used to evaluate the potential to convert ferrous to ferric iron and to provide in situ treatment and precipitation. Mine flooding averaged 31 cm/day with a linear shape until November 2007, when it flattened out due to outflow. During flooding, mine water pH remained around 6, but Eh shifted from 200 to -150 mV. After the mine water level stabilized, contents of elements such as Fe and SO(4) tended to decrease as time passed. Air was injected by diffusers (150 L/min/each) at three different depths of 2, 3, and 5 m below the water level in the shaft. Dissolved oxygen eventually increased to 4 or 5 mg/L depending on the depth of the diffusers. Aeration caused conversion of ferrous iron to ferric iron and about 30 mg/l of iron was removed from the mine water. Therefore, air injection shows potential as a semi-active treatment or part of conventional treatment to precipitate iron in the mine pool.

Cherenkov Radiation from a Pseudospark-sourced Electron Beam

International Nuclear Information System (INIS)

Phelps, A.D.R.; Yin, H.; Cross, A.W.; He, W.; Ronald, K.

2003-01-01

Electron beam generation from a multi-gap pseudospark discharge was investigated. A pseudospark-sourced electron beam has two phases, an initial hollow cathode phase (HCP) beam followed by a conductive phase (CP) beam. The beam brightness was measured by a field-free collimator to be 109 and 1011 Am-2rad-2 for the hollow cathode phase (HCP) beam and the conductive phase (CP) beam respectively. The initial HCP beam from an eight-gap pseudospark discharge was applied in a Cherenkov interaction between the electron beam and the TM01 mode of a 60-cm long alumina-lined waveguide. It was found experimentally that significant microwave radiation was generated only when the dielectric was present in the interaction space. If there was no dielectric in the cylindrical waveguide, then a very small background microwave output was detected even when the guide B-field was absent. This demonstrated, in conjunction with the observation that the microwave output signal was independent of the guide magnetic field over the range 0.13 to 0.26 T, that the radiation from the experiment was due to the Cherenkov interaction mechanism. In addition, two components of the microwave pulse were observed corresponding to the two energy components of the electron beam during the pseudospark discharge breakdown. These results demonstrated that the microwave radiation was generated by Cherenkov amplification of the broadband emission from the pseudospark discharge itself. A background signal level of around 100 W was measured in the frequency range 20 - 50 GHz with a percentage of (2.7 ± 0.6)% in the frequency range 25.5 - 28.6 GHz, when the dielectric lining was removed from the maser. The frequency of the microwave output after the Cherenkov maser interaction was measured to be mainly around 25.5 GHz and the dominating mode was identified as being TM01. The duration of the microwave pulse was approximately 80 ns, with a peak power of around 2 ± 0.2 kW. The gain of this amplifier was measured

A quartz Cherenkov detector for polarimetry at the ILC

International Nuclear Information System (INIS)

Vauth, Annika

2014-09-01

At the proposed International Linear Collider (ILC), the use of polarised electron and positron beams is a key ingredient of the physics program. A measurement of the polarisation with a yet unprecedented precision of δP / P =0.25% is required. To achieve this, Compton polarimeter measurements in front of and behind the collision point are foreseen. In this thesis, a novel concept for a detector for ILC polarimetry is introduced to eliminate one of the dominating systematics limiting the previous best measurement of beam polarisation: a detector using quartz as Cherenkov medium could increase the tolerance against non-linear photodetector responses. The high refractive index of quartz results in a higher Cherenkov light yield compared to conventional Cherenkov gases. This could allow single-peak resolution in the Cherenkov photon spectra produced by the Compton electrons at the polarimeters. The detailed simulation studies presented in this work imply that such single-peak resolution is possible. Considerations for the choice of a suitable detector geometry are discussed. A four-channel prototype has been constructed and successfully operated in a first testbeam campaign at the DESY testbeam, confirming simulation predictions. Although further studies have to be considered to quantify all aspects of the detector response, the findings of the analysis of the data from the first testbeam are promising with regards to reaching the desired light yield. In the final part of this thesis, the application of a detector concept allowing single-peak resolution to the polarisation measurement at the ILC is examined. Two of the main sources of systematic uncertainties on the polarimeter measurements are detector non-linearities and misalignments. The performance of the suggested quartz detector concept in Monte Carlo studies promises a control of these systematics which meets the precision requirements for ILC polarimetry.

Underground gasification and combustion brown with the use of groundwater

Directory of Open Access Journals (Sweden)

Zholudyev S.V.

2011-11-01

Full Text Available The problems of coal excavation and environement protection are priority for Ukraine. Underground coal gasification (UCG and underground coal incineration (UCI are combining excavation with simultaneous underground processing in entire technological process, capable to solve this problem. Using an intermediate heat carrier - ground water may optimisating of these processes.

Cherenkov radiation as a means of radio isotope diagnosis of eyeball tumors

International Nuclear Information System (INIS)

Moshnikov, O.S.; Kolesnichenko, V.N.

1986-01-01

Radiophosphorus indication of eye new-growths can be accomplished through registration of beta-particle or Cherenkov radiation. In both cases the criterion for the conclusion to be drawn from the experimental results is the relative increment of the count rate. The article analyses the specific features of the equipment aimed at recording Cherenkov radiation in the process of radiophosphorus studied in ophthalmology, and discusses the method for these studies. (orig.)

FACT light collection - solid light concentrators in Cherenkov Astronomy

Energy Technology Data Exchange (ETDEWEB)

Braun, Isabel [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Collaboration: FACT-Collaboration

2011-07-01

Pixelized cameras of Imaging Atmospheric Cherenkov Telescopes use hollow light guides with reflective surfaces based on the Winston cone design. These cones minimize insensitive spaces between the photo sensors and shield the camera from stray background light by limiting the angular acceptance to the primary reflector area. FACT (First G-APD Cherenkov Telescope) will be the first IACT with Geiger-mode avalanche photodiodes as light sensors. Solid light concentrators complementing these sensors will be used instead of hollow Winston cones. We will present simulations and measurements of our light collector design, which was optimized for the requirements of the FACT telescope and detector, and discuss the specific differences to more traditional solutions.

High speed decision electronics combined to a beam Cherenkov counter

International Nuclear Information System (INIS)

Sghaier, H.

1993-01-01

The Hypolit detector for identification of particles in high energy physics using the Cherenkov radiation, is based on an intensifier tube coupled to photomultipliers via a fiber-optic matrix. Cherenkov photons are focused into a ring; particle identification consists in calculating the ring radius. A fast and high level electronic system is associated to Hypolit. Besides deriving the radius, it allows a background rejection and achieves a momentum correction. This on line tagging contributes to build the WA89 trigger. Tuning is controlled with a micro-computer which makes the access to the heart of the system friendly-user

A new approach to the theory of Cherenkov radiation based on relativistic generalization of the Landau criterion

International Nuclear Information System (INIS)

Chefranov, S.G.

2004-01-01

Relativistic generalization of the Landau criterion is obtained which, in contrast to the classical Tamm-Frank and Ginzburg theories, determines the primary energy mechanism of emission of nonbremsstrahlung Cherenkov radiation. It is shown that Cherenkov radiation may correspond to a threshold energetically favorable conversion of the condensate (ultimately long-wavelength) elementary Bose perturbations of a medium into transverse Cherenkov photons emitted by the medium proper during its interaction with a sufficiently fast charged particle. The threshold conditions of emission are determined for a medium with an arbitrary refractive index n, including the case of isotropic plasma with n < 1 for which the classical theory of Cherenkov radiation prohibits such direct and effective nonbremsstrahlung emission of these particular transverse high-frequency electromagnetic waves. It is established that these conditions of emission agree with the data of well-known experiments on the threshold for observation of Cherenkov radiation, whereas the classical theory only corresponds to the conditions of observation of the interference maximum of this radiation. The possibility of direct effective emission of nonbremsstrahlung Cherenkov radiation, not taken into account in the classical theory, is considered for many observed astrophysical phenomena (type III solar radio bursts, particle acceleration by radiation, etc.)

Time and charge calibration of Cherenkov telescope data acquired by Domino Ring Sampler 4 chips

Energy Technology Data Exchange (ETDEWEB)

Hoerbe, Mario; Doert, Marlene [Ruhr-Universitaet Bochum (Germany); Bruegge, Kai; Buss, Jens; Bockermann, Christian; Egorov, Alexej [TU Dortmund (Germany)

2016-07-01

Very-high-energy gamma-ray astronomy aims to give an insight into the most energetic phenomena in our Universe. Earthbound Cherenkov telescopes can measure Cherenkov light emitted by atmospheric particle showers which are produced by incoming cosmic particles at high energies. Current Cherenkov telescopes, e.g. operated in the FACT and the MAGIC experiments, utilize Domino Ring Sampler 4 (DRS4) chips for recording signals at high speed coming from the telescopes' cameras. DRS4 chips will also be used in the cameras of the Large-Size telescopes of the projected Cherenkov Telescope Array (CTA). We aim at developing a software solution for the calibration of DRS4 data based on the streams-framework, a software tool for streaming analysis which has been developed within the Collaborative Research Center SFB 876. The objectives and the current status of the project are presented.

Integral study of the quantity and quality of the underground water in the Santa Lucia basin in Uruguay

International Nuclear Information System (INIS)

1990-01-01

This work study different aspects about the underground water in the Santa Lucia sedimentary basin in Uruguay. It is situated between the San Jose and Santa Lucia river as well as the adyacent Rio de La Plata coast.

The application of alpha-card measurement to search underground water resources in bedrock

International Nuclear Information System (INIS)

Xiong Fulin; Liang Jinhua

1986-01-01

The alpha-card measurement is a new kind of nuclear technique to evaluate the concentration of the radium and thorium emanations with a short-time accumulation. It has shown the wonderful characteristics of higher sensitivity, greater detective depth, less interference and shorter work period when applied to search underground water resources in bedrock. The satisfactory result of its application in Pingyin limestone area is described. The principle of the alpha-card measurement and the foundation of its application are briefly discussed

MO-AB-BRA-08: Rapid Treatment Field Uniformity Optimization for Total Skin Electron Beam Therapy Using Cherenkov Imaging

International Nuclear Information System (INIS)

Andreozzi, J; Zhang, R; Glaser, A; Pogue, B; Jarvis, L; Williams, B; Gladstone, D

2015-01-01

Purpose: To evaluate treatment field heterogeneity resulting from gantry angle choice in total skin electron beam therapy (TSEBT) following a modified Stanford dual-field technique, and determine a relationship between source to surface distance (SSD) and optimized gantry angle spread. Methods: Cherenkov imaging was used to image 62 treatment fields on a sheet of 1.2m x 2.2m x 1.2cm polyethylene following standard TSEBT setup at our institution (6 MeV, 888 MU/min, no spoiler, SSD=441cm), where gantry angles spanned from 239.5° to 300.5° at 1° increments. Average Cherenkov intensity and coefficient of variation in the region of interest were compared for the set of composite Cherenkov images created by summing all unique combinations of angle pairs to simulate dual-field treatment. The angle pair which produced the lowest coefficient of variation was further studied using an ionization chamber. The experiment was repeated at SSD=300cm, and SSD=370.5cm. Cherenkov imaging was also implemented during TSEBT of three patients. Results: The most uniform treatment region from a symmetric angle spread was achieved using gantry angles +/−17.5° about the horizontal axis at SSD=441cm, +/−18.5° at SSD=370.5cm, and +/−19.5° at SSD=300cm. Ionization chamber measurements comparing the original treatment spread (+/−14.5°) and the optimized angle pair (+/−17.5°) at SSD=441cm showed no significant deviation (r=0.999) in percent depth dose curves, and chamber measurements from nine locations within the field showed an improvement in dose uniformity from 24.41% to 9.75%. Ionization chamber measurements correlated strongly (r=0.981) with Cherenkov intensity measured concurrently on the flat Plastic Water phantom. Patient images and TLD results also showed modest uniformity improvements. Conclusion: A decreasing linear relationship between optimal angle spread and SSD was observed. Cherenkov imaging offers a new method of rapidly analyzing and optimizing TSEBT setup

Cherenkov ring imaging using a television digitizer

International Nuclear Information System (INIS)

Charpak, G.; Peisert, A.; Sauli, F.; Cavestro, A.; Vascon, M.; Zanella, G.

1981-01-01

A Cherenkov ring imaging device using as photon detector a multistep spark chamber coupled to a television digitizer is described. Results of a test run using triethylamine as photo-ionizing vapour are presented, as well as preliminary results obtained with a new vapour having an extremely low ionization potential. (orig.)

The Tunka-133 EAS Cherenkov light array: Status of 2011

International Nuclear Information System (INIS)

Berezhnev, S.F.; Besson, D.; Budnev, N.M.; Chiavassa, A.; Chvalaev, O.A.; Gress, O.A.; Dyachok, A.N.; Epimakhov, S.N.; Haungs, A.; Karpov, N.I.; Kalmykov, N.N.; Konstantinov, E.N.; Korobchenko, A.V.; Korosteleva, E.E.; Kozhin, V.A.; Kuzmichev, L.A.; Lubsandorzhiev, B.K.; Lubsandorzhiev, N.B.; Mirgazov, R.R.; Panasyuk, M.I.

2012-01-01

A new EAS Cherenkov light array, Tunka-133, with ∼1km 2 geometrical area has been installed at the Tunka Valley (50 km from Lake Baikal) in 2009. The array permits a detailed study of cosmic ray energy spectrum and mass composition in the energy range 10 16 –10 18 eV with a uniform method. We describe the array construction, DAQ and methods of the array calibration. The method of energy reconstruction and absolute calibration of measurements are discussed. The analysis of spatial and time structure of EAS Cherenkov light allows to estimate the depth of the EAS maximum X max . The results on the all particles energy spectrum and the mean depth of the EAS maximum X max vs. primary energy derived from the data of two winter seasons (2009–2011) are presented. Preliminary results of joint operation of the Cherenkov array with antennas for the detection of EAS radio signals are shown. Plans for future upgrades – deployment of remote clusters, radioantennas and a scintillator detector network and a prototype of the HiSCORE gamma-telescope – are discussed.

Logistics background study: underground mining

Energy Technology Data Exchange (ETDEWEB)

Hanslovan, J. J.; Visovsky, R. G.

1982-02-01

Logistical functions that are normally associated with US underground coal mining are investigated and analyzed. These functions imply all activities and services that support the producing sections of the mine. The report provides a better understanding of how these functions impact coal production in terms of time, cost, and safety. Major underground logistics activities are analyzed and include: transportation and personnel, supplies and equipment; transportation of coal and rock; electrical distribution and communications systems; water handling; hydraulics; and ventilation systems. Recommended areas for future research are identified and prioritized.

SU-C-201-07: Towards Clinical Cherenkov Emission Dosimetry: Stopping Power-To-Cherenkov Power Ratios and Beam Quality Specification of Clinical Electron Beams

International Nuclear Information System (INIS)

Zlateva, Y; Seuntjens, J; El Naqa, I

2016-01-01

Purpose: We propose a Cherenkov emission (CE)-based reference dosimetry method, which in contrast to ionization chamber-based dosimetry, employs spectrum-averaged electron restricted mass collision stopping power-to-Cherenkov power ratios (SCRs), and we examine Monte Carlo-calculated SCRs and beam quality specification of clinical electron beams. Methods: The EGSnrc user code SPRRZnrc was modified to compute SCRs instead of stopping-power ratios (single medium: water; cut-off: CE threshold (observing Spencer-Attix conditions); CE power: Frank-Tamm). SCRs are calculated with BEAMnrc for realistic electron beams with nominal energies of 6–22 MeV from three Varian accelerators (TrueBeam Clinac 21EX, Clinac 2100C/D) and for mono-energetic beams of energies equal to the mean electron energy at the water surface. Sources of deviation between clinical and mono-energetic SCRs are analyzed quantitatively. A universal fit for the beam-quality index R_5_0 in terms of the depth of 50% CE C_5_0 is carried out. Results: SCRs at reference depth are overestimated by mono-energetic values by up to 0.2% for a 6-MeV beam and underestimated by up to 2.3% for a 22-MeV beam. The variation is mainly due to the clinical beam spectrum and photon contamination. Beam angular spread has a small effect across all depths and energies. The influence of the electron spectrum becomes increasingly significant at large depths, while at shallow depths and high beam energies photon contamination is predominant (up to 2.0%). The universal data fit reveals a strong linear correlation between R_5_0 and C_5_0 (ρ > 0.99999). Conclusion: CE is inherent to radiotherapy beams and can be detected outside the beam with available optical technologies, which makes it an ideal candidate for out-of-beam high-resolution 3D dosimetry. Successful clinical implementation of CE dosimetry hinges on the development of robust protocols for converting measured CE to radiation dose. Our findings constitute a key step

A quartz Cherenkov detector for Compton-polarimetry at future e+e- colliders

International Nuclear Information System (INIS)

List, Jenny; Vauth, Annika; Vormwald, Benedikt; Hamburg Univ.

2015-02-01

Precision polarimetry is essential for future e + e - colliders and requires Compton polarimeters designed for negligible statistical uncertainties. In this paper, we discuss the design and construction of a quartz Cherenkov detector for such Compton polarimeters. The detector concept has been developed with regard to the main systematic uncertainties of the polarisation measurements, namely the linearity of the detector response and detector alignment. Simulation studies presented here imply that the light yield reachable by using quartz as Cherenkov medium allows to resolve in the Cherenkov photon spectra individual peaks corresponding to different numbers of Compton electrons. The benefits of the application of a detector with such single-peak resolution to the polarisation measurement are shown for the example of the upstream polarimeters foreseen at the International Linear Collider. Results of a first testbeam campaign with a four-channel prototype confirming simulation predictions for single electrons are presented.

Cherenkov detectors for spatial imaging applications using discrete-energy photons

Energy Technology Data Exchange (ETDEWEB)

Rose, Paul B.; Erickson, Anna S., E-mail: erickson@gatech.edu [Georgia Institute of Technology, Nuclear and Radiological Engineering, G.W. Woodruff School of Mechanical Engineering, 770 State St., Atlanta, Georgia 30332 (United States)

2016-08-14

Cherenkov detectors can offer a significant advantage in spatial imaging applications when excellent timing response, low noise and cross talk, large area coverage, and the ability to operate in magnetic fields are required. We show that an array of Cherenkov detectors with crude energy resolution coupled with monochromatic photons resulting from a low-energy nuclear reaction can be used to produce a sharp image of material while providing large and inexpensive detector coverage. The analysis of the detector response to relative transmission of photons with various energies allows for reconstruction of material's effective atomic number further aiding in high-Z material identification.

Pilot-scale study of the radiation-induced silica removal from underground brackish water in Saudi Arabia

Energy Technology Data Exchange (ETDEWEB)

Aljohani, Mohammed S. [King Abdulaziz Univ., Jeddah (Saudi Arabia). Nuclear Engineering Dept.

2017-08-01

Silica scaling deposition in industrial water systems is one of the biggest challenges facing the water treatment industry due the low solubility of the scalants in the feed waters. In this preliminary work, we investigated the effectiveness of the ionizing radiation induced removal of silica in water sample from the Salbukh, Saudi Arabia, water treatment plant by using metallic iron as the source of ferric hydroxide to co-precipitate the silica. The influence of several reaction parameters, i.e. iron powder dosage, radiation dose, initial pH and equilibrium pH effect were investigated. In the optimum conditions, up to 75% of silica was removed. This preliminary study showed that this environmentally friendly process is effective in silica removal from underground water.

Silica aerogel threshold Cherenkov counters for the JLab Hall A spectrometers: improvements and proposed modifications

CERN Document Server

Lagamba, L; Colilli, S; Crateri, R; De Leo, R; Frullani, S; Garibaldi, F; Giuliani, F; Gricia, M; Iodice, M; Iommi, R; Leone, A; Lucentini, M; Mostarda, A; Nappi, E; Perrino, R; Pierangeli, L; Santavenere, F; Urciuoli, G M

2001-01-01

Recently approved experiments at Jefferson Lab Hall A require a clean kaon identification in a large electron, pion, and proton background environment. To this end, improved performance is required of the silica aerogel threshold Cherenkov counters installed in the focal plane of the two Hall A spectrometers. In this paper we propose two strategies to improve the performance of the Cherenkov counters which presently use a hydrophilic aerogel radiator, and convey Cherenkov photons towards the photomultipliers by means of mirrors with a parabolic shape in one direction and flat in the other. The first strategy is aerogel baking. In the second strategy we propose a modification of the counter geometry by replacing the mirrors with a planar diffusing surface and by displacing in a different way the photomultipliers. Tests at CERN with a 5 GeV/c multiparticle beam revealed that both the strategies are able to increase significantly the number of the detected Cherenkov photons and, therefore, the detector performan...

Investigation of the connection between surface water and underground water from mine Cacova-Ierii, using activable tracers

International Nuclear Information System (INIS)

Dinescu, L.; Domocos, V.; Craciun, St.

1985-01-01

Two tracers, indium in the form of In-EDTA complex and 82 Br were simultaneously used in mining hydrology studies. The water samples were passed through an ion exchange column retaining the other disturbing elements, such as Mn, Cl, Na, K etc. Indium was coprecipitated with bismuth hydroxide and determined by NAA. Ten samples of precipitate in plastic bags, wrapped in Al foil, and the standard were irradiated simultaneously for 20 minutes by 10 13 n/cm 2 s neutron flux in the VVR-S reactor, and measured immeadiately after irradiation. Measurements were performed with a Ge(Li) detector and ND-6620 data acquisition and processing system. Measuring time was 200 s. The desintegration correction was taken into account for concentration calculations. Bromine 82 was determined by ''in situ'' measurements with scintillation probe. The connection between surface water and underground Cacova-Ierii mine water was proved, and data regarding the velocity and circulation were obtained

Wavelet imaging cleaning method for atmospheric Cherenkov telescopes

Science.gov (United States)

Lessard, R. W.; Cayón, L.; Sembroski, G. H.; Gaidos, J. A.

2002-07-01

We present a new method of image cleaning for imaging atmospheric Cherenkov telescopes. The method is based on the utilization of wavelets to identify noise pixels in images of gamma-ray and hadronic induced air showers. This method selects more signal pixels with Cherenkov photons than traditional image processing techniques. In addition, the method is equally efficient at rejecting pixels with noise alone. The inclusion of more signal pixels in an image of an air shower allows for a more accurate reconstruction, especially at lower gamma-ray energies that produce low levels of light. We present the results of Monte Carlo simulations of gamma-ray and hadronic air showers which show improved angular resolution using this cleaning procedure. Data from the Whipple Observatory's 10-m telescope are utilized to show the efficacy of the method for extracting a gamma-ray signal from the background of hadronic generated images.

Observation of Cherenkov rings using a low-pressure parallel-plate chamber and a solid cesium-iodide photocathode

International Nuclear Information System (INIS)

Lockyer, N.S.; Millan, J.E.; Lu, C.; McDonald, K.T.; Lopez, A.

1993-01-01

We have observed Cherenkov rings from minimum-ionizing particles using a low-pressure, parallel-plate pad-chamber with a cesium-iodide solid photocathode. This detector is blind to minimum-ionizing particles, and sensitive to Cherenkov photons of wavelengths 170-210 nm. An average of 5 photoelectrons per Cherenkov ring were detected using a 2-cm-thick radiator of liquid C 6 F 14 . This paper reports on the chamber construction, photocathode preparation and testbeam results. (orig.)

Calculational model for condensation of water vapor during an underground nuclear detonation

International Nuclear Information System (INIS)

Knox, R.J.

1975-01-01

An empirally derived mathematical model was developed to calculate the pressure and temperature history during condensation of water vapor in an underground-nuclear-explosion cavity. The condensation process is non-isothermal. Use has been made of the Clapeyron-Clausius equation as a basis for development of the model. Analytic fits to the vapor pressure and the latent heat of vaporization for saturated-water vapor, together with an estimated value for the heat-transfer coefficient, have been used to describe the phenomena. The calculated pressure-history during condensation has been determined to be exponential, with a time constant somewhat less than that observed during the cooling of the superheated steam from the explosion. The behavior of the calculated condensation-pressure compares well with the observed-pressure record (until just prior to cavity collapse) for a particular nuclear-detonation event for which data is available

Noise simulation and rejection for the DELPHI Barrel Ring Imaging Cherenkov detector

International Nuclear Information System (INIS)

Bloch, D.

1996-01-01

The performance of Ring Imaging Cherenkov detectors is severely affected by the background noise due to the necessity of detecting single electrons. Furthermore, in the majority of the existing RICHs, the charged particles to be identified also cross the sensitive area of the apparatus thus creating secondary effects. The different noise sources and the background behaviour have been studied for the DELPHI RICH in order to efficiently clean the Cherenkov rings from the background while preserving the majority of the signal. Particular care has been taken to optimize the parameters of the Cherenkov image ''cleaning'' for the gas and the liquid radiators separately. For Z 0 hadronic decays 70% background rejection has been achieved, whilst 85% of the signal has been retained. This paper also presents a simulation of the noise producing mechanisms where ionization electrons, δ-rays, feedback electrons created during avalanches and electronic noise are modeled according to the measured parameters. Good agreement between data and simulation has been achieved. (orig.)

Development of aerogel Cherenkov counters at Novosibirsk

International Nuclear Information System (INIS)

Barnyakov, A.Yu.; Barnyakov, M.Yu.; Baehr, J.; Bellunato, T.; Beloborodov, K.I.; Bobrovnikov, V.S.; Buzykaev, A.R.; Calvi, M.; Danilyuk, A.F.; Djordjadze, V.; Golubev, V.B.; Kononov, S.A.; Kravchenko, E.A.; Lipka, D.; Matteuzzi, C.; Musy, M.; Onuchin, A.P.; Perego, D.; Rodiakin, V.A.; Savinov, G.A.; Serednyakov, S.I.; Shamov, A.G.; Stephan, F.; Tayursky, V.A.; Vorobiov, A.I.

2006-01-01

The work on aerogel Cherenkov counters was started in Novosibirsk in 1986. Production of aerogels with refractive indices of 1.006-1.13 and thicknesses of blocks up to 50mm was developed. The light absorption length at 400nm is 5-7m, the scattering length is 4-5cm. By these parameters, the Novosibirsk aerogel is one of the best in the world. The ASHIPH Cherenkov counters with light collection on wavelength shifters have been developed. The ASHIPH system of the KEDR detector contains 1000l of aerogel. The π/K separation is 4.5σ. A project of ASHIPH counters for the SND detector has been developed. Aerogel RICH for LHCb gives a possibility to identify hadrons in the momentum range of 2-10GeV/c. The Novosibirsk group is developing an aerogel RICH for the endcap for the SuperBaBar project. Calculations performed by a group of physicists from Novosibirsk and DESY-Zeuthen have shown that aerogel radiators enable to achieve time resolution up to 20fs

The establishment of a method for evaluating the long-term water-tightness durability of underground concrete structure taking into account some deteriorations

International Nuclear Information System (INIS)

Hironaga, Michihiko; Kawanishi, Motoi

1996-01-01

To establish a method of evaluating the long-term water-tightness durability of underground concrete structures, the authors firstly studied a deterioration evaluation model to express the deterioration condition of concrete structures and constructed, on the basis of this model, a function evaluation model to estimate the lowering of functions due to deterioration, consequently indicating a 'concept for evaluating the deterioration and functions of concrete structures' which will make it possible to perform the functional evaluation of concrete structures. Based on this concept, the authors then discusses a technique for evaluating the long-term water-tightness durability of underground concrete structures, specifically indicating the technique by means of illustrations. (author)

Monitor and control systems for the SLD Cherenkov Ring Imaging Detector

International Nuclear Information System (INIS)

Antilogus, P.; Aston, D.; Bienz, T.; Boston Univ., MA; California Univ., Santa Barbara, CA; California Univ., Santa Cruz, CA; Cincinnati Univ., OH; Rutgers--the State Univ., Piscataway, NJ; Tohoku Univ., Sendai

1989-10-01

To help ensure the stable long-term operation of a Cherenkov Ring Detector at high efficiency, a comprehensive monitor and control system is being developed. This system will continuously monitor and maintain the correct operating temperatures, and will provide an on-line monitor and maintain the correct operating temperatures, and will provide an on-line monitor of the pressures, flows, mixing, and purity of the various fluids. In addition the velocities and trajectories of Cherenkov photoelectrons drifting within the imaging chambers will be measured using a pulsed uv lamp and a fiberoptic light injection system. 9 refs., 6 figs

Design and construction of a Cherenkov detector for Compton polarimetry at the ILC

International Nuclear Information System (INIS)

Bartels, Christoph

2010-11-01

This paper describes the design and construction of a Cherenkov detector conceived with regard to high energy Compton polarimeters for the International Linear Collider, where beam diagnostic systems of unprecedented precision must complement the interaction region detectors to pursue an ambitious physics programme. Besides the design of the Cherenkov detector, detailed simulation studies and first testbeam results are presented. Good agreement of beam data with expectations from Monte Carlo simulations is observed. (orig.)

Design and construction of a Cherenkov detector for Compton polarimetry at the ILC

Energy Technology Data Exchange (ETDEWEB)

Bartels, Christoph [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hamburg Univ. (Germany). Inst. fuer Experimentalphysik; Ebert, Joachim; Hartin, Anthony; Helebrant, Christian; Kaefer, Daniela; List, Jenny [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2010-11-15

This paper describes the design and construction of a Cherenkov detector conceived with regard to high energy Compton polarimeters for the International Linear Collider, where beam diagnostic systems of unprecedented precision must complement the interaction region detectors to pursue an ambitious physics programme. Besides the design of the Cherenkov detector, detailed simulation studies and first testbeam results are presented. Good agreement of beam data with expectations from Monte Carlo simulations is observed. (orig.)

Recent results from the DELPHI barrel ring imaging Cherenkov counter

International Nuclear Information System (INIS)

Anassontzis, E.G.; Ioannou, P.; Kalkanis, G.; Katsanevas, S.; Kontaxis, I.; Kourkoumelis, C.; Nounos, S.; Preve, P.; Resvanis, L.K.; Brunet, J.M.; Dolbeau, J.; Guglielmo, L.; Ledroit, F.; Poutot, D.; Tristram, G.

1991-01-01

The DELPHI detector, installed at LEP, is equipped with RICH (Ring Imaging Cherenkov) counters. The Barrel part incorporates a liquid (C 6 F 14 ) and a gaseous (C 5 F 12 ) radiator providing particle identification up to 20GeV/c. The Cherenkov protons of both radiators are detected by TPC-like photon detectors. The drift gas (75% CH 4 + 25% C 2 H 6 ) is doped with TMAE, but which the UV Cherenkov photons are converted into single free photo-electrons. These are drifted towards MWPC's at the end of the drift tubes and the space coordinates of the conversion point are determined. One half of the Barrel RICH is now equipped with drift tubes and has provided results from the liquid radiator since spring 1990. The gas radiator has been tested with C 2 F 6 as a preliminary filling since August 1990. The data obtained demonstrate the good particle identification potential. For the liquid radiator the number of detected photons per ring in hadron jets is N=8, whereas for muon pairs (single tracks) N=10 has been obtained. For the gas radiator 2.1 photons per track were observed, which demonstrates the good functioning of the focussing mirrors, as the C 2 F 6 this is close to the expected value

Workshop on Non-Imaging Cherenkov at High Energy

CERN Document Server

2013-01-01

The non-Imaging Cherenkov air shower measurement technique holds great promise in furthering our understanding the Knee-to-Ankle region of the cosmic ray spectrum. In particular, this technique offers a unique way to determine the evolution of the cosmic ray nuclear composition, and an example is given by the recent spectrum results of the Tunka Collaboration. With this in mind, we are organizing a workshop, to be held at the University of Utah, to bring together the various practitioners of this cosmic ray measurement technique to share simulations, analyses, detector designs, and past experimental results amongst the community. The workshop will also be in support of our effort, NICHE, to extend the reach of the TA/TALE detector systems down to the Knee. We anticipate that the workshop will result in a white paper on the scientific importance of these high-energy cosmic ray measurements and on using the Cherenkov technique to accomplish them. Our goal is to have contributions from members of the previous ge...

Spectrometer of Cherenkov radiation rings with hodoscopic photomultipliers

International Nuclear Information System (INIS)

Abramov, V.V.; Alekseev, A.V.; Baldin, B.Yu.

1983-01-01

Characteristics of SKOCH Cherenkov radiation ring spectrometer intended for identification of π- and K-mesons and protons in a wide divergent beam in the pulse range of 5.5-30 GeV/s are investigated. The spectrometer detecting system is based on using the hodoscopic photoelectron multipliers (HPEM). The HPEM specific feature is that they have an extended cathode and permit to determine the coordinate of an incident photon by measuring the time of photoelectron drift to a dinode system. The spectrometer has been tested at the FODS facility in the secondary particle beam with angular divergence equal to 16x6 mrad and aperture of 400x200 mm in the pulse range of 6-20 GeV/s. The range of Cherenkov radiation angle detection is 40-100 mrad which corresponds to the particle velocity range of 0.996-1. The angular and radial aperture is 30 mrad, the diameter is 420 mm. The obtained velocity resolution is 6x10 -5

A Cherenkov-emission Microwave Source*

Science.gov (United States)

Lai, C. H.; Yoshii, J.; Katsouleas, T.; Hairapetian1, G.; Joshi, C.; Mori, W.

1996-11-01

In an unmagnetized plasma, there is no Cherenkov emission because the phase velocity vf of light is greater than c. In a magnetized plasma, the situation is completely changed. There is a rich variety of plasma modes with phase velocities vf 2 c which can couple to a fast particle. In the magnetized plasma, a fast particle, a particle beam, or even a short laser pulse excites a Cherenkov wake that has both electrostatic and electromagnetic components. Preliminary simulations indicate that at the vacuum/plasma boundary, the wake couples to a vacuum microwave with an amplitude equal to the electromagnetic component in the plasma. For a weakly magnetized plasma, the amplitude of the out-coupled radiation is approximately wc/wp times the amplitude of the wake excited in the plasma by the beam, and the frequency is approximately wp. Since plasma wakes as high as a few GeV/m are produced in current experiments, the potential for a high-power (i.e., GWatt) coherent microwave to THz source exists. In this talk, a brief overview of the scaling laws will be presented, followed by 1-D and 2-D PIC simulations. Prospects for a tuneable microwave source experiment based on this mechanism at the UCLA plasma wakefield accelerator facility will be discussed. *Work supported by AFOSR Grant #F4 96200-95-0248 and DOE Grant # DE-FG03-92ER40745. 1Now at Hughes Research Laboratories, Malibu, CA 90265

Underground dams for irrigation supplies in coastal limestone aquifer, Okinawa, Japan

Science.gov (United States)

Yasumoto, J.; Nakano, T.; Nawa, N.

2011-12-01

The use of underground dams to store water in regions with arid or tropical climates is a method that has received considerable attention in the last few decades. And now, for the tropical and subtropical islands that are highly vulnerable to climate change underground dams have been attracting attention again as a method of groundwater management. Okinawa Prefecture is Japan's southernmost prefecture, which consists of hundreds of islands in a chain over 1,000 km long, called the Ryukyu Islands which extend southwest from Kyushu to Taiwan. The national irrigation project of the Ryukyu Islands has been carried out, and several underground dams have been constructed. The Komesu and Giiza underground dams are first full scale underground dam facilities constructed for irrigation in Japan. The Komesu underground dam is a salt-water proof type. It prevents salt-water intrusion and provides storage fresh-water for irrigation in coastal limestone aquifer. Giiza underground dam is a dam up type for storage of fresh-water. These groundwater reservoirs are located in the coastal region of southern part of Okinawa (main island), where Ryukyu limestone is extensively distributed. We studied the behaviour of groundwater flow, saltwater intrusion and nitrate nitrogen (NO3-N) in groundwater in this region by using observation data of groundwater and springs through long term (from 1993 to 2010) monitoring. And, a groundwater flow and salt-water intrusion analysis have been conducted with three dimensional numerical model applied to these dam reservoir areas. The MODFLOW-NWT with SWI code and PEST was used to simulate the complex groundwater flow patterns. Through the comparison with simulation and observed data, it was concluded that the cut off wall of underground dams effectively stores the groundwater and prevents the salt-water intrusion in the reservoir areas. The observed groundwater levels at the reservoir areas were almost reproduced by the numerical model, but there

Evaluation of antibiotic resistant bacteria in underground drinking water and transfer of their resistant character to normal flora of the body.

Science.gov (United States)

Alam, Mehboob; Khan, Naqab; Rehman, Khurram; Khan, Samiullah; Niazi, Zahid Rasul; Shah, Kifayatullah; Baloch, Natasha; Khan, Barkat Ali

2018-03-01

The untreated surface water for drinking and domestic use is an alarming situation to public health especially in prevalence of antibiotics resistant bacteria. This investigation aimed to isolate and identify the antibiotic resistance bacteria in underground water samples in district Dera Ismail Khan, Pakistan. The underground water samples were collected from four different places using hand pumps (Khyber town, riverside, Gomal University and united town). Cultured on nutrient agar media, identified by Gam staining and biochemical tests. There after antibiotic resistance assay were performed by measuring zone of inhibition of different antibiotics by disc diffusion method. Six different bacterial colonies were isolated and identified as Enterobacteriaceae, Serriata specie, Proteues, Pseudomonas, all these bacterial colonies were 33% resistant to chloramphenicol with and 100% resistant to amoxicillin. Some colonies were also considered as resistant, according to the criteria of National Committee for Clinical Records (NCCL) that less than 10mm zone of inhibition are considered as resistant. Subsequently, the chloramphenicol resistance bacteria were analyzed for their ability to transfer resistant gene to sensitive bacteria. In in-vitro method, an isolate M1b (resistant) was found capable to transfer resistance gene to M1a isolate (sensitive) in nutrient rich environment. It was concluded that antibiotics resistance bacteria found in underground water, moreover capable of transferring the antibiotic resistant character to suitable recipient i.e. normal flora of the body or to other pathogens by conjugation.

Evaluation of new 5 inch photomultiplier for use in threshold Cherenkov detectors with aerogel radiator

International Nuclear Information System (INIS)

Wojtsekhowski, B.; Zorn, C.; Flyckt, S.O.

2000-01-01

A cost effective alternative to UV-sensitive 5 inch PMTs often used with threshold Aerogel Cherenkov detectors has been developed and tested. The photomultiplier -XP4572-is a variation of the Photonis XP4512 glass window tube with improved electron collection efficiency. Fast timing and high gain were only moderately compromised. The effective quantum efficiency has been measured as twice that of a Burle 8854 Quantacon when exposed to a Cherenkov spectrum generated by Ru-106 electrons (les;3.54 MeV) through 1 cm of high index, high transparency Matsushita Electric aerogel (n=1.05). This new phototube is being installed in an aerogel-based Cherenkov detector for Hall A at Jefferson Lab

The influence of the mining activity in the Oltenia region on the underground water resources and their quality

International Nuclear Information System (INIS)

Baican, G.; Fodor, D.; Rotunjanu, I.

1998-01-01

The mining activity in Oltenia's area has affected both the hydro-geographical network and underground water resources, the regime and their quality. Due to mining and dewatering works resulted depression areas with negative effects on environment and water feeding for localities as well as for economic-social objectives in area. The measures that have been taken in order to decrease negative effects as well as results obtained, can be found in the paper

WE-AB-303-04: A Tissue Model of Cherenkov Emission From the Skin Surface During Megavoltage X-Ray Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Wiles, A. N.; Loyalka, S. K. [University of Missouri, Columbia, MO (United States); Izaguirre, E. W. [University of Missouri, Columbia, MO (United States); Baylor Scott & White Health, Temple, TX (United States)

2015-06-15

Purpose: To develop a tissue model of Cherenkov radiation emitted from the skin surface during external beam radiotherapy. Imaging Cherenkov radiation emitted from human skin allows visualization of the beam position and potentially surface dose estimates, and our goal is to characterize the optical properties of these emissions. Methods: We developed a Monte Carlo model of Cherenkov radiation generated in a semi-infinite tissue slab by megavoltage x-ray beams with optical transmission properties determined by a two-layered skin model. We separate the skin into a dermal and an epidermal layer in our model, where distinct molecular absorbers modify the Cherenkov intensity spectrum in each layer while we approximate the scattering properties with Mie and Rayleigh scattering from the highly structured molecular organization found in human skin. Results: We report on the estimated distributions of the Cherenkov wavelength spectrum, emission angles, and surface distribution for the modeled irradiated skin surface. The expected intensity distribution of Cherenkov radiation emitted from skin shows a distinct intensity peak around 475 nm, the blue region of the visible spectrum, between a pair of optical absorption bands in hemoglobin and a broad plateau beginning near 600 nm and extending to at least 700 nm where melanin and hemoglobin absorption are both low. We also find that the Cherenkov intensity decreases with increasing angle from the surface normal, the majority being emitted within 20 degrees of the surface normal. Conclusion: Our estimate of the spectral distribution of Cherenkov radiation emitted from skin indicates an advantage to using imaging devices with long wavelength spectral responsivity. We also expect the most efficient imaging to be near the surface normal where the intensity is greatest; although for contoured surfaces, the relative intensity across the surface may appear to vary due to decreasing Cherenkov intensity with increased angle from the

Performance study of wavelength shifting acrylic plastic for Cherenkov light detection

Energy Technology Data Exchange (ETDEWEB)

Beckford, B., E-mail: beckford@aps.org [American Physical Society, One Physics Ellipse, College Park, MD 20740 (United States); De la Puente, A. [TRIUMF Laboratory, 4004 Wesbrook Mall, Vancouver, BC, Canada V6T 2A3 (Canada); Fujii, Y.; Hashimoto, O.; Kaneta, M.; Kanda, H.; Maeda, K.; Matsumura, A.; Nakamura, S.N. [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Perez, N.; Reinhold, J. [Department of Physics, Florida International University, Miami, FL 33199 (United States); Tang, L. [Department of Physics, Hampton University, Hampton, VA 23668 (United States); Tsukada, K. [Department of Physics, Tohoku University, Sendai 980-8578 (Japan)

2014-01-21

The collection efficiency for Cherenkov light incident on a wavelength shifting plate (WLS) has been determined during a beam test at the Proton Synchrotron facility located in the National Laboratory for High Energy Physics (KEK), Tsukuba, Japan. The experiment was conducted in order to determine the detector's response to photoelectrons converted from photons produced by a fused silica radiator; this allows for an approximation of the detector's quality. The yield of the photoelectrons produced through internally generated Cherenkov light as well as light incident from the radiator was measured as a function of the momentum of the incident hadron beam. The yield is proportional to sin{sup 2}θ{sub c}, where θ{sub c} is the opening angle of the Cherenkov light created. Based on estimations and results from similar conducted tests, where the collection efficiency was roughly 39%, the experimental result was expected to be around 40% for internally produced light from the WLS. The results of the experiment determined the photon collection response efficiency of the WLS to be roughly 62% for photons created in a fused silica radiator and 41% for light created in the WLS.

Underground gasification in Britain

Energy Technology Data Exchange (ETDEWEB)

1952-08-29

A report of the discussion held on the paper Underground Gasification in Britain, by C.A. Masterman (Iron and Coal Trades Rev., Vol. 165, Aug. 22, 1952, pp. 413-422). The water question, preheating the air, controlling the gas, using the product, choosing the site, thickness of seam and faulted areas are discussed.

The Cherenkov correlated timing detector: materials, geometry and timing constraints

International Nuclear Information System (INIS)

Aronstein, D.; Bergfeld, T.; Horton, D.; Palmer, M.; Selen, M.; Thayer, G.; Boyer, V.; Honscheid, K.; Kichimi, H.; Sugaya, Y.; Yamaguchi, H.; Yoshimura, Y.; Kanda, S.; Olsen, S.; Ueno, K.; Tamura, N.; Yoshimura, K.; Lu, C.; Marlow, D.; Mindas, C.; Prebys, E.; Pomianowski, P.

1996-01-01

The key parameters of Cherenkov correlated timing (CCT) detectors are discussed. Measurements of radiator geometry, optical properties of radiator and coupling materials, and photon detector timing performance are presented. (orig.)

Construction and maintenance of underground mine roads

Energy Technology Data Exchange (ETDEWEB)

Logan, A.S.; Seedsman, R.W. [Coffey Partners International Pty. Ltd. (Australia)

1995-12-31

Good roads are essential in moving men and materials to and from the underground workplace. An underground coal industry funded project was recently completed on underground mine road construction and maintenance. This paper discusses practical approaches to construction and maintenance of underground mine roads using transferable civil technologies and innovative techniques. Mine pavements are generally low-cost (relative to civil roads), constructed to varying standards using locally available materials to best meet the mobility needs of the mine. Performance of pavements is thus largely dependent on the environmental conditions, quality of the available road making materials, maintenance policies and available resources. This paper explains the causes of bad roads in various underground environments. It details available management strategies, construction and water control techniques, road maintenance and vehicle considerations. It concludes that the trend to larger rubber tires mining equipment needs to be matched with construction and maintenance of high quality road surfaces. For large operations, the total cost due to poor roads may equate to in excess of $A1 million per annum. The strategies outlined in this paper provide the basis for construction and maintenance of underground mine roads to help achieve desired production targets. (author). 2 tabs., 4 figs., 7 refs.

Moura tragedy the model for this year's underground exercise

Energy Technology Data Exchange (ETDEWEB)

1991-10-01

Mines Rescue teams in the 1991 E.K. Healy cup competition handled an underground exercise based on the Moura No. 4 colliery explosion which killed 12 miners on July 16, 1986. The contest organisers and hosts went to great lengths to achieve realism. This included underground water barriers and ventilation tubes being tossed around, meat, offal and bullock's blood being strewn and using trickel dusters to produce a smoke effect restricting visibility to 20 metres. The other exercises in the contest were: a theory test; and exercise involving gas monitoring, power isolation and fire fighting; and a first aid section dealt with an electrical accident near water. The task in the underground exercise was to retrieve information. The Chairman of the Assessors reported that the theory and fire fighting were handled fairly well. Handling of the electrical incident was not too bad, with the life saving techniques being very well done. The underground exercise revealed different ways of gathering information. While leadership styles and team member interaction varied this was not detrimental to efficiency. 9 photos.

Cherenkov detectors and a new effective-mass spectrometer method

Czech Academy of Sciences Publication Activity Database

Hladký, Jan

2006-01-01

Roč. 75, - (2006), s. 854-855 ISSN 0969-806X Institutional research plan: CEZ:AV0Z10100502 Keywords : Cherenkov radiation * spectrometer * effective mass method Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.868, year: 2006

LUCID A Cherenkov Tube Based Detector for Monitoring the ATLAS Experiment Luminosity

CERN Document Server

Sbrizzi, A

2007-01-01

The LUCID (LUminosity Cherenkov Integrating Detector) apparatus is composed by two symmetric arms deployed at about 17 m from the ATLAS interaction point. The purpose of this detector, which will be installed in january 2008, is to monitor the luminosity delivered by the LHC machine to the ATLAS experiment. An absolute luminosity calibration is needed and it will be provided by a Roman Pot type detector with the two arms placed at about 240 m from the interaction point. Each arm of the LUCID detector is based on an aluminum vessel containing 20 Cherenkov tubes, 15 mm diameter and 1500 mm length, filled with C4F10 radiator gas at 1.5 bar. The Cherenkov light generated by charged particles above the threshold is collected by photomultiplier tubes (PMT) directly placed at the tubes end. The challenging aspect of this detector is its readout in an environment characterized by the high dose of radiation (about 0.7 Mrad/year at 10^33cm^2 s^-1) it must withstand. In order to fulfill these radiation hardness requirem...

Modeling the Effects of Mirror Misalignment in a Ring Imaging Cherenkov Detector

Science.gov (United States)

Hitchcock, Tawanda; Harton, Austin; Garcia, Edmundo

2012-03-01

The Very High Momentum Particle Identification Detector (VHMPID) has been proposed for the ALICE experiment at the Large Hadron Collider (LHC). This detector upgrade is considered necessary to study jet-matter interaction at high energies. The VHMPID identifies charged hadrons in the 5 GeV/c to 25 GeV/c momentum range. The Cherenkov photons emitted in the VHMPID radiator are collected by spherical mirrors and focused onto a photo-detector plane forming a ring image. The radius of this ring is related to the Cherenkov angle, this information coupled with the particle momentum allows the particle identification. A major issue in the RICH detector is that environmental conditions can cause movements in mirror position. In addition, chromatic dispersion causes the refractive index to shift, altering the Cherenkov angle. We are modeling a twelve mirror RICH detector taking into account the effects of mirror misalignment and chromatic dispersion using a commercial optical software package. This will include quantifying the effects of both rotational and translational mirror misalignment for the initial assembly of the module and later on particle identification.

Calibration of Cherenkov detectors for monoenergetic photon imaging in active interrogation applications

Energy Technology Data Exchange (ETDEWEB)

Rose, P.B., E-mail: prose6@gatech.edu; Erickson, A.S., E-mail: anna.erickson@me.gatech.edu

2015-11-01

Active interrogation of cargo containers using monoenergetic photons offers a rapid and low-dose approach to search for shielded special nuclear materials. Cherenkov detectors can be used for imaging of the cargo provided that gamma ray energies used in interrogation are well resolved, as the case in {sup 11}B(d,n-γ){sup 12}C reaction resulting in 4.4 MeV and 15.1 MeV photons. While an array of Cherenkov threshold detectors reduces low energy background from scatter while providing the ability of high contrast transmission imaging, thus confirming the presence of high-Z materials, these detectors require a special approach to energy calibration due to the lack of resolution. In this paper, we discuss the utility of Cherenkov detectors for active interrogation with monoenergetic photons as well as the results of computational and experimental studies of their energy calibration. The results of the studies with sources emitting monoenergetic photons as well as complex gamma ray spectrum sources, for example {sup 232}Th, show that calibration is possible as long as the energies of photons of interest are distinct.

Cherenkov radiation imaging of beta emitters: in vitro and in vivo results

International Nuclear Information System (INIS)

Spinelli, Antonello E.; Boschi, Federico; D'Ambrosio, Daniela; Calderan, Laura; Marengo, Mario; Fenzi, Alberto; Menegazzi, Marta; Sbarbati, Andrea; Del Vecchio, Antonella; Calandrino, Riccardo

2011-01-01

The main purpose of this work was to investigate both in vitro and in vivo Cherenkov radiation (CR) emission coming from 18 F and 32 P. The main difference between 18 F and 32 P is mainly the number of the emitted light photons, more precisely the same activity of 32 P emits more CR photons with respect to 18 F. In vitro results obtained by comparing beta counter measurements with photons average radiance showed that Cherenkov luminescence imaging (CLI) allows quantitative tracer activity measurements. In order to investigate in vivo the CLI approach, we studied an experimental xenograft tumor model of mammary carcinoma (BB1 tumor cells). Cherenkov in vivo dynamic whole body images of tumor bearing mice were acquired and the tumor tissue time activity curves reflected the well-known physiological accumulation of 18 F-FDG in malignant tissues with respect to normal tissues. The results presented here show that it is possible to use conventional optical imaging devices for in vitro or in vivo study of beta emitters.

Cherenkov radiation imaging of beta emitters: in vitro and in vivo results

Energy Technology Data Exchange (ETDEWEB)

Spinelli, Antonello E., E-mail: spinelli.antonello@hsr.it [Medical Physics Department, S. Raffaele Scientific Institute, Via Olgettina N. 60, Milan (Italy); Boschi, Federico [Department of Morphological-Biomedical Sciences, University of Verona, Strada Le Grazie N. 8, Verona (Italy); D' Ambrosio, Daniela [Medical Physics Department, S. Orsola-Malpighi University Hospital, via Massarenti N. 9, Bologna (Italy); Calderan, Laura [Department of Morphological-Biomedical Sciences, University of Verona, Strada Le Grazie N. 8, Verona (Italy); Marengo, Mario [Medical Physics Department, S. Orsola-Malpighi University Hospital, via Massarenti N. 9, Bologna (Italy); Fenzi, Alberto [Department of Morphological-Biomedical Sciences, University of Verona, Strada Le Grazie N. 8, Verona (Italy); Menegazzi, Marta [Department of Life and Reproduction Sciences, University of Verona, Strada Le Grazie N. 8, Verona (Italy); Sbarbati, Andrea [Department of Morphological-Biomedical Sciences, University of Verona, Strada Le Grazie N. 8, Verona (Italy); Del Vecchio, Antonella; Calandrino, Riccardo [Medical Physics Department, S. Raffaele Scientific Institute, Via Olgettina N. 60, Milan (Italy)

2011-08-21

The main purpose of this work was to investigate both in vitro and in vivo Cherenkov radiation (CR) emission coming from {sup 18}F and {sup 32}P. The main difference between {sup 18}F and {sup 32}P is mainly the number of the emitted light photons, more precisely the same activity of {sup 32}P emits more CR photons with respect to {sup 18}F. In vitro results obtained by comparing beta counter measurements with photons average radiance showed that Cherenkov luminescence imaging (CLI) allows quantitative tracer activity measurements. In order to investigate in vivo the CLI approach, we studied an experimental xenograft tumor model of mammary carcinoma (BB1 tumor cells). Cherenkov in vivo dynamic whole body images of tumor bearing mice were acquired and the tumor tissue time activity curves reflected the well-known physiological accumulation of {sup 18}F-FDG in malignant tissues with respect to normal tissues. The results presented here show that it is possible to use conventional optical imaging devices for in vitro or in vivo study of beta emitters.

Photon counting with a FDIRC Cherenkov prototype readout by SiPM arrays

Energy Technology Data Exchange (ETDEWEB)

Marrocchesi, P.S., E-mail: marrocchesi@pi.infn.it [Department of Physical Sciences, Earth and Environment, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy); Bagliesi, M.G. [Department of Physical Sciences, Earth and Environment, Via Roma 56, I-53100 Siena (Italy); Basti, A. [Department of Physics, University of Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy); INFN Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy); Bigongiari, G.; Bonechi, S.; Brogi, P. [Department of Physical Sciences, Earth and Environment, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy); Checchia, C.; Collazuol, G. [Department of Physics and Astronomy, University of Padova, Padova, Italy, and INFN-Padova, 35131 Padova (Italy); Maestro, P. [Department of Physical Sciences, Earth and Environment, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy); Morsani, F. [INFN Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy); Piemonte, C. [Fondazione Bruno Kessler (FBK), I-38122 Trento (Italy); Stolzi, F.; Suh, J.E; Sulaj, A. [Department of Physical Sciences, Earth and Environment, Via Roma 56, I-53100 Siena (Italy); INFN Sezione di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa (Italy)

2017-02-11

A prototype of a Focused Internal Reflection Cherenkov, equipped with 16 arrays of NUV-SiPM, was tested at CERN SPS in March 2015 with beams of relativistic ions at 13, 19 and 30 GeV/n obtained from fragmentation of an Ar primary beam. The detector, designed to identify cosmic nuclei, features a Fused Silica radiator bar optically connected to a cylindrical mirror of the same material and an imaging focal plane of dimensions ∼4 cm×3 cm covered with a total of 1024 SiPM photosensors. Thanks to the outstanding performance of the SiPM arrays, the detector could be operated in photon counting mode as a fully digital device. The Cherenkov pattern was recorded together with the total number of detected photoelectrons increasing as Z{sup 2} as a function of the atomic number Z of the beam particle. In this paper, we report on the characterization and test of the SiPM arrays and the performance of the Cherenkov prototype for the charge identification of the beam particles.

30 CFR 784.25 - Return of coal processing waste to abandoned underground workings.

Science.gov (United States)

2010-07-01

... water underground, treatment of water if released to surface streams, and the effect on the hydrologic... the regulatory authority and the Mine Safety and Health Administration under 30 CFR 817.81(f). (b... of the mine void to be filled, method of constructing underground retaining walls, influence of the...

Signal intensity analysis and optimization for in vivo imaging of Cherenkov and excited luminescence

Science.gov (United States)

LaRochelle, Ethan P. M.; Shell, Jennifer R.; Gunn, Jason R.; Davis, Scott C.; Pogue, Brian W.

2018-04-01

During external beam radiotherapy (EBRT), in vivo Cherenkov optical emissions can be used as a dosimetry tool or to excite luminescence, termed Cherenkov-excited luminescence (CEL) with microsecond-level time-gated cameras. The goal of this work was to develop a complete theoretical foundation for the detectable signal strength, in order to provide guidance on optimization of the limits of detection and how to optimize near real time imaging. The key parameters affecting photon production, propagation and detection were considered and experimental validation with both tissue phantoms and a murine model are shown. Both the theoretical analysis and experimental data indicate that the detection level is near a single photon-per-pixel for the detection geometry and frame rates commonly used, with the strongest factor being the signal decrease with the square of distance from tissue to camera. Experimental data demonstrates how the SNR improves with increasing integration time, but only up to the point where the dominance of camera read noise is overcome by stray photon noise that cannot be suppressed. For the current camera in a fixed geometry, the signal to background ratio limits the detection of light signals, and the observed in vivo Cherenkov emission is on the order of 100×  stronger than CEL signals. As a result, imaging signals from depths  <15 mm is reasonable for Cherenkov light, and depths  <3 mm is reasonable for CEL imaging. The current investigation modeled Cherenkov and CEL imaging of two oxygen sensing phosphorescent compounds, but the modularity of the code allows for easy comparison of different agents or alternative cameras, geometries or tissues.

Development of a diagnostic technique based on Cherenkov effect for measurements of fast electrons in fusion devices

Energy Technology Data Exchange (ETDEWEB)

Plyusnin, V. V.; Duarte, P.; Fernandes, H.; Silva, C. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Jakubowski, L.; Zebrowski, J.; Malinowski, K.; Rabinski, M.; Sadowski, M. J. [National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock (Poland)

2012-08-15

A diagnostic technique based on the Cherenkov effect is proposed for detection and characterization of fast (super-thermal and runaway) electrons in fusion devices. The detectors of Cherenkov radiation have been specially designed for measurements in the ISTTOK tokamak. Properties of several materials have been studied to determine the most appropriate one to be used as a radiator of Cherenkov emission in the detector. This technique has enabled the detection of energetic electrons (70 keV and higher) and the determination of their spatial and temporal variations in the ISTTOK discharges. Measurement of hard x-ray emission has also been carried out in experiments for validation of the measuring capabilities of the Cherenkov-type detector and a high correlation was found between the data of both diagnostics. A reasonable agreement was found between experimental data and the results of numerical modeling of the runaway electron generation in ISTTOK.

Prediction of underground argon content for dark matter experiments

International Nuclear Information System (INIS)

Mei, D.-M.; Spaans, J.; Keller, C.; Yin, Z.-B.; Koppang, M.; Hime, A.; Gehman, V. M.

2010-01-01

In this paper, we demonstrate the use of physical models to evaluate the production of 39 Ar and 40 Ar underground. Considering both cosmogenic 39 Ar production and radiogenic 40 Ar production in situ and from external sources, we can derive the ratio of 39 Ar to 40 Ar in underground sources. We show for the first time that the 39 Ar production underground is dominated by stopping negative muon capture on 39 K and (α,n) induced subsequent 39 K(n,p) 39 Ar reactions. The production of 39 Ar is shown as a function of depth. We demonstrate that argon depleted in 39 Ar can be obtained only if the depth of the underground resources is greater than 500 m.w.e. below the surface. Stopping negative muon capture on 39 K dominates over radiogenic production at depths of less than 2000 m.w.e., and that production by muon-induced neutrons is subdominant at any depth. The depletion factor depends strongly on both radioactivity level and potassium content in the rock. We measure the radioactivity concentration and potassium concentration in the rock for a potential site of an underground argon source in South Dakota. Depending on the probability of 39 Ar and 40 Ar produced underground being dissolved in the water, the upper limit of the concentration of 39 Ar in the underground water at this site is estimated to be in a range of a factor of 1.6 to 155 less than the 39 Ar concentration in the atmosphere. The calculation tools presented in this paper are also critical to the dating method with 39 Ar.

Cherenkov imaging method for rapid optimization of clinical treatment geometry in total skin electron beam therapy

Energy Technology Data Exchange (ETDEWEB)

Andreozzi, Jacqueline M., E-mail: Jacqueline.M.Andreozzi.th@dartmouth.edu, E-mail: Lesley.A.Jarvis@hitchcock.org; Glaser, Adam K. [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Zhang, Rongxiao [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Gladstone, David J.; Williams, Benjamin B.; Jarvis, Lesley A., E-mail: Jacqueline.M.Andreozzi.th@dartmouth.edu, E-mail: Lesley.A.Jarvis@hitchcock.org [Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766 (United States); Pogue, Brian W. [Thayer School of Engineering and Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)

2016-02-15

Purpose: A method was developed utilizing Cherenkov imaging for rapid and thorough determination of the two gantry angles that produce the most uniform treatment plane during dual-field total skin electron beam therapy (TSET). Methods: Cherenkov imaging was implemented to gather 2D measurements of relative surface dose from 6 MeV electron beams on a white polyethylene sheet. An intensified charge-coupled device camera time-gated to the Linac was used for Cherenkov emission imaging at sixty-two different gantry angles (1° increments, from 239.5° to 300.5°). Following a modified Stanford TSET technique, which uses two fields per patient position for full body coverage, composite images were created as the sum of two beam images on the sheet; each angle pair was evaluated for minimum variation across the patient region of interest. Cherenkov versus dose correlation was verified with ionization chamber measurements. The process was repeated at source to surface distance (SSD) = 441, 370.5, and 300 cm to determine optimal angle spread for varying room geometries. In addition, three patients receiving TSET using a modified Stanford six-dual field technique with 6 MeV electron beams at SSD = 441 cm were imaged during treatment. Results: As in previous studies, Cherenkov intensity was shown to directly correlate with dose for homogenous flat phantoms (R{sup 2} = 0.93), making Cherenkov imaging an appropriate candidate to assess and optimize TSET setup geometry. This method provided dense 2D images allowing 1891 possible treatment geometries to be comprehensively analyzed from one data set of 62 single images. Gantry angles historically used for TSET at their institution were 255.5° and 284.5° at SSD = 441 cm; however, the angles optimized for maximum homogeneity were found to be 252.5° and 287.5° (+6° increase in angle spread). Ionization chamber measurements confirmed improvement in dose homogeneity across the treatment field from a range of 24.4% at the initial

Photon detection in ring imaging Cherenkov counters

International Nuclear Information System (INIS)

Jansen, H.

1988-01-01

One of the parts of DELPHI (a detector at the CERN LEP) is the barrel-RICH which uses Cherenkov radiation to determine the velocity of charged particles; together with the measured momentum this information yields the mass of each particle. The performance of the photon detector, which determines to a large extent the analyzing power of the barrel-RICH, is studied. 98 refs.; 40 figs.; 6 tabs

Test of aerogel as Cherenkov radiator

CERN Document Server

Alemi, M; Calvi, M; Matteuzzi, C; Negri, P; Paganoni, M; Liko, D; Neufeld, N; Chesi, Enrico Guido; Joram, C; Séguinot, Jacques; Ypsilantis, Thomas

2001-01-01

Two different stacks of aerogel were tested in a pion/proton beam of momentum between 3 and 10 GeV/c. The optical characteristics of the aerogel samples were different: one sample was hygroscopic while the other was hydrophobic. Two HPD tubes were used as photodetectors, and different thicknesses of the stacks were used, in order to determine the photoelectron yield, the Cherenkov angle and its precision. Pion/proton separation has been demonstrated at momenta up to 10 GeV/c.

NECTAR: New electronics for the Cherenkov Telescope Array

Science.gov (United States)

Naumann, Christopher Lindsay; Bolmont, J.; Corona, P.; Delagnes, E.; Dzahini, D.; Feinstein, F.; Gascon, D.; Glicenstein, J.-F.; Nayman, P.; Rarbi, F.; Ribo, M.; Sanuy, A.; Siero, X.; Tavernet, J.-P.; Toussenel, F.; Vincent, P.; Vorobiov, S.

2012-12-01

The international CTA consortium is currently in the preparatory phase for the development of the next-generation Cherenkov Telescope Array (CTA [1]), based on the return of experience from the three major current-generation arrays H.E.S.S., MAGIC and VERITAS. To achieve an unprecedented sensitivity and energy range for TeV gamma rays, a new kind of flexible and powerful yet inexpensive front-end hardware will be required for the order of 105 channels of photodetectors in up to 100 telescopes. One possible solution is the NECTAr (New Electronics for the Cherenkov Telescope Array) system, based on the integration of as much as possible of the front-end electronics (amplifiers, fast analogue samplers, memory and ADCs) into a single ASIC for very fast readout performance and a significant reduction of the cost and the lower consumption per channel, while offering a high degree of flexibility both for the triggering and the readout of the telescope. The current status of its development is presented, along with newest results from measurements and simulation studies.

INFN Camera demonstrator for the Cherenkov Telescope Array

CERN Document Server

Ambrosi, G; Aramo, C.; Bertucci, B.; Bissaldi, E.; Bitossi, M.; Brasolin, S.; Busetto, G.; Carosi, R.; Catalanotti, S.; Ciocci, M.A.; Consoletti, R.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; de Palma, F.; Desiante, R.; Di Girolamo, T.; Di Giulio, C.; Doro, M.; D'Urso, D.; Ferraro, G.; Ferrarotto, F.; Gargano, F.; Giglietto, N.; Giordano, F.; Giraudo, G.; Iacovacci, M.; Ionica, M.; Iori, M.; Longo, F.; Mariotti, M.; Mastroianni, S.; Minuti, M.; Morselli, A.; Paoletti, R.; Pauletta, G.; Rando, R.; Fernandez, G. Rodriguez; Rugliancich, A.; Simone, D.; Stella, C.; Tonachini, A.; Vallania, P.; Valore, L.; Vagelli, V.; Verzi, V.; Vigorito, C.

2015-01-01

The Cherenkov Telescope Array is a world-wide project for a new generation of ground-based Cherenkov telescopes of the Imaging class with the aim of exploring the highest energy region of the electromagnetic spectrum. With two planned arrays, one for each hemisphere, it will guarantee a good sky coverage in the energy range from a few tens of GeV to hundreds of TeV, with improved angular resolution and a sensitivity in the TeV energy region better by one order of magnitude than the currently operating arrays. In order to cover this wide energy range, three different telescope types are envisaged, with different mirror sizes and focal plane features. In particular, for the highest energies a possible design is a dual-mirror Schwarzschild-Couder optical scheme, with a compact focal plane. A silicon photomultiplier (SiPM) based camera is being proposed as a solution to match the dimensions of the pixel (angular size of ~ 0.17 degrees). INFN is developing a camera demonstrator made by 9 Photo Sensor Modules (PSMs...

Realisation and tests of a compressed gas Cherenkov counter. Study of the pollution of a beam (1961); Realisation et essais d'un compteur cherenkov a gaz comprime etude de la pollution d'un faisceau (1961)

Energy Technology Data Exchange (ETDEWEB)

Duboc, J; Banaigs, J; Detoeuf, J F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

The realisation of a compressed as Cherenkov counter permits the study of the pollution of a beam of {pi} mesons with momentum varying from 220 to 11000 MeV/c. (authors) [French] La realisation d'un compteur Cherenkov a gaz sous pression permet l'etude de la pollution d'un faisceau de mesons {pi} d'impulsions comprise entre 220 et 1100 MeV/c. (auteurs)

Measurement of high-energy electrons by means of a Cherenkov detector in ISTTOK tokamak

Energy Technology Data Exchange (ETDEWEB)

Jakubowski, L., E-mail: lech.Jjakubowski@ipj.gov.p [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Zebrowski, J. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Plyusnin, V.V. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Av. Rovisco Pais, 1049 - 001 Lisboa (Portugal); Malinowski, K.; Sadowski, M.J.; Rabinski, M. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Fernandes, H.; Silva, C.; Duarte, P. [Association Euratom/IST, Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Av. Rovisco Pais, 1049 - 001 Lisboa (Portugal)

2010-10-15

The paper concerns detectors of the Cherenkov radiation which can be used to measure high-energy electrons escaping from short-living plasma. Such detectors have high temporal (about 1 ns) and spatial (about 1 mm) resolution. The paper describes a Cherenkov-type detector which was designed, manufactured and installed in the ISTTOK tokamak in order to measure fast runaway electrons. The radiator of that detector was made of an aluminium nitride (AlN) tablet with a light-tight filter on its front surface. Cherenkov signals from the radiator were transmitted through an optical cable to a fast photomultiplier. It made possible to perform direct measurements of the runaway electrons of energy above 80 keV. The measured energy values and spatial characteristics of the recorded electrons appeared to be consistent with results of numerical modelling of the runaway electron generation process in the ISTTOK tokamak.

Gamma ray astronomy with atmospheric Cherenkov telescopes: the future

International Nuclear Information System (INIS)

Krennrich, Frank

2009-01-01

Atmospheric Cherenkov telescopes have been key to the recent discoveries in teraelectronvolt (TeV) γ-ray astronomy. The detection of TeV γ rays from more than 90 galactic and extragalactic sources provides a wealth of data for probing physical phenomena that pertain to some of the big questions in astrophysics. These include the understanding of the origin of cosmic rays, unveiling the connection between relativistic jets and black holes, shedding light on dark matter and its relation to supersymmetric particles and estimating the brightness of cosmological diffuse radiation fields in the optical/infrared waveband. While these recent advances were made with instruments designed in the 1990s, the present paper is concerned with a next generation of imaging atmospheric Cherenkov telescopes (IACTs) that are currently in the conceptual planning stage. We discuss the basic ideas, the required technology and expected performance of a ≥1 square-kilometer array, which is poised to yield the most dramatic step yet to come in TeV astronomy.

Extremely frequency-widened terahertz wave generation using Cherenkov-type radiation.

Science.gov (United States)

Suizu, Koji; Koketsu, Kaoru; Shibuya, Takayuki; Tsutsui, Toshihiro; Akiba, Takuya; Kawase, Kodo

2009-04-13

Terahertz (THz) wave generation based on nonlinear frequency conversion is promising way for realizing a tunable monochromatic bright THz-wave source. Such a development of efficient and wide tunable THz-wave source depends on discovery of novel brilliant nonlinear crystal. Important factors of a nonlinear crystal for THz-wave generation are, 1. High nonlinearity and 2. Good transparency at THz frequency region. Unfortunately, many nonlinear crystals have strong absorption at THz frequency region. The fact limits efficient and wide tunable THz-wave generation. Here, we show that Cherenkov radiation with waveguide structure is an effective strategy for achieving efficient and extremely wide tunable THz-wave source. We fabricated MgO-doped lithium niobate slab waveguide with 3.8 microm of thickness and demonstrated difference frequency generation of THz-wave generation with Cherenkov phase matching. Extremely frequency-widened THz-wave generation, from 0.1 to 7.2 THz, without no structural dips successfully obtained. The tuning frequency range of waveguided Cherenkov radiation source was extremely widened compare to that of injection seeded-Terahertz Parametric Generator. The tuning range obtained in this work for THz-wave generation using lithium niobate crystal was the widest value in our knowledge. The highest THz-wave energy obtained was about 3.2 pJ, and the energy conversion efficiency was about 10(-5) %. The method can be easily applied for many conventional nonlinear crystals, results in realizing simple, reasonable, compact, high efficient and ultra broad band THz-wave sources.

Cherenkov light as a source of photochemical reactions in irradiated solutions of nitrile of malachite green

Energy Technology Data Exchange (ETDEWEB)

Stuglik, Z; Grodkowski, J

1986-10-01

Experimental data on photochemical activity of Cherenkov light are presented. Malachite green leucocyanide was used to detect the photochemical effects. The G value of Cherenkov light from the region 200-330 nm (number of quanta formed per 100 eV absorbed energy of ionizing radiation) in ethanol was estimated to be in the range of 0.0027-0.049. 14 references.

Cherenkov light as a source of photochemical reactions in irradiated solutions of nitrile of malachite green

International Nuclear Information System (INIS)

Stuglik, Z.; Grodkowski, J.

1986-01-01

Experimental data on photochemical activity of Cherenkov light are presented. Malachite green leucocyanide was used to detect the photochemical effects. The G value of Cherenkov light from the region 200-330 nm (number of quanta formed per 100 eV absorbed energy of ionizing radiation) in ethanol was estimated to be in the range of 0.0027-0.049. (author)

Regulatory mechanisms for underground waste disposal in Nigeria ...

African Journals Online (AJOL)

Michael Horsfall

Environmental Pollution Control in Nigeria, National Guidelines on Waste Disposal through Underground ... dead, domestic waste and, excrement in this manner. The soil and geological formations that are the waste ... waste water daily is presently seeking partnerships with the ... role in ground water quality protection from.

Aerogel Cherenkov detector for characterizing the intense flash x-ray source, Cygnus, spectrum

Energy Technology Data Exchange (ETDEWEB)

Kim, Y., E-mail: yhkim@lanl.gov; Herrmann, H. W.; McEvoy, A. M.; Young, C. S.; Hamilton, C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Schwellenbach, D. D.; Malone, R. M.; Kaufman, M. I.; Smith, A. S. [National Security Technologies, LLC, Los Alamos, New Mexico 87544 (United States)

2016-11-15

An aerogel Cherenkov detector is proposed to measure the X-ray energy spectrum from the Cygnus—intense flash X-ray source operated at the Nevada National Security Site. An array of aerogels set at a variety of thresholds between 1 and 3 MeV will be adequate to map out the bremsstrahlung X-ray production of the Cygnus, where the maximum energy of the spectrum is normally around 2.5 MeV. In addition to the Cherenkov radiation from aerogels, one possible competing light-production mechanism is optical transition radiation (OTR), which may be significant in aerogels due to the large number of transitions from SiO{sub 2} clusters to vacuum voids. To examine whether OTR is a problem, four aerogel samples were tested using a mono-energetic electron beam (varied in the range of 1–3 MeV) at NSTec Los Alamos Operations. It was demonstrated that aerogels can be used as a Cherenkov medium, where the rate of the light production is about two orders magnitude higher when the electron beam energy is above threshold.

Using of ozone and UV in the treatment of N'djamena's municipal underground water

International Nuclear Information System (INIS)

Mohagir, A. M.; New, M. Tchadanaye; Nanadoum, M.; Tchadanaye, M.; Kapseu, C.; Kamga, R.; Tchiegang, C.; Bup, N. D.

2008-01-01

The presence of some epidemics such as cholera typhoid and renal failure were reported frequently in the last 3 years. Since the quality of potable water might be responsible for those diseases. this research work was focused on underground water of N'djamena's municipal on which almost all population of this capital used it as drinking water without purifications samples from 3 different locations were analysed for pH, Ca ++ , Fe ++ , Na + , C1 - , NO 3 - , and SO 4 2- . In addition some microbial analyses before and after treatment were done. Ozone and UV as oxidative and destructive agents were used among the procedure of treatment. The result revealed that filtration process has a significant at P> 0.01 for the removal of total hardness. On the other hand, using of ozone and UV showed a significant difference at P> 0.001 for overcoming the presence of bacteria and aerobic germs. Intensive research works were recommended to minimize the risk that could be associated with drinking water. (author)

Extension of Cherenkov Light LDF Parametrization for Tunka and ...

Indian Academy of Sciences (India)

2016-01-27

Jan 27, 2016 ... The Cherenkov light Lateral Distribution Function (LDF) from particles initiated Extensive Air Showers (EAS) with ultrahigh energies ( > 1016 eV) was simulated using CORSIKA program for configuration of Tunka and Yakutsk EAS arrays for different primary particles (p, Fe and O2) and different zenith ...

Radionuclides in an underground environment

International Nuclear Information System (INIS)

Thompson, J.L.

1996-01-01

In the 100 years since Becquerel recognized radioactivity, mankind has been very successful in producing large amounts of radioactive materials. We have been less successful in reaching a consensus on how to dispose of the billions of curies of fission products and transuranics resulting from nuclear weapons testing, electrical power generation, medical research, and a variety of other human endeavors. Many countries, including the United States, favor underground burial as a means of disposing of radioactive wastes. There are, however, serious questions about how such buried wastes may behave in the underground environment and particularly how they might eventually contaminate water, air and soil resources on which we are dependent. This paper describes research done in the United States in the state of Nevada on the behavior of radioactive materials placed underground. During the last thirty years, a series of ''experiments'' conducted for other purposes (testing of nuclear weapons) have resulted in a wide variety of fission products and actinides being injected in rock strata both above and below the water table. Variables which seem to control the movement of these radionuclides include the physical form (occlusion versus surface deposition), the chemical oxidation state, sorption by mineral phases of the host rock, and the hydrologic properties of the medium. The information gained from these studies should be relevant to planning for remediation of nuclear facilities elsewhere in the world and for long-term storage of nuclear wastes

Underground infrastructure damage for a Chicago scenario

Energy Technology Data Exchange (ETDEWEB)

Dey, Thomas N [Los Alamos National Laboratory; Bos, Rabdall J [Los Alamos National Laboratory

2011-01-25

Estimating effects due to an urban IND (improvised nuclear device) on underground structures and underground utilities is a challenging task. Nuclear effects tests performed at the Nevada Test Site (NTS) during the era of nuclear weapons testing provides much information on how underground military structures respond. Transferring this knowledge to answer questions about the urban civilian environment is needed to help plan responses to IND scenarios. Explosions just above the ground surface can only couple a small fraction of the blast energy into an underground shock. The various forms of nuclear radiation have limited penetration into the ground. While the shock transmitted into the ground carries only a small fraction of the blast energy, peak stresses are generally higher and peak ground displacement is lower than in the air blast. While underground military structures are often designed to resist stresses substantially higher than due to the overlying rocks and soils (overburden), civilian structures such as subways and tunnels would generally only need to resist overburden conditions with a suitable safety factor. Just as we expect the buildings themselves to channel and shield air blast above ground, basements and other underground openings as well as changes of geology will channel and shield the underground shock wave. While a weaker shock is expected in an urban environment, small displacements on very close-by faults, and more likely, soils being displaced past building foundations where utility lines enter could readily damaged or disable these services. Immediately near an explosion, the blast can 'liquefy' a saturated soil creating a quicksand-like condition for a period of time. We extrapolate the nuclear effects experience to a Chicago-based scenario. We consider the TARP (Tunnel and Reservoir Project) and subway system and the underground lifeline (electric, gas, water, etc) system and provide guidance for planning this scenario.

The cosmic ray proton, helium and CNO fluxes in the 100 TeV energy region from TeV muons and EAS atmospheric Cherenkov light observations of MACRO and EAS-TOP

CERN Document Server

Aglietta, M; Ambrosio, M; Antolini, R; Antonioli, P; Arneodo, F; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bergamasco, L; Bernardini, P; Bertaina, M; Bilokon, H; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Castagnoli, C; Castellina, A; Cecchini, S; Cei, F; Chiarella, V; Chiarusi, T; Chiavassa, A; Choudhary, B C; Cini, G; Coutu, S; Cozzi, M; De Cataldo, G; De Marzo, C; De Mitri, I; De Vincenzi, M; Dekhissi, H; Derkaoui, J; Di Credico, A; Di Sciascio, G; Erriquez, O; Favuzzi, C; Forti, C; Fulgione, W; Fusco, P; Galeotti, P; Ghia, P L; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iacovacci, M; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Mannocchi, G; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Morello, C; Mufson, S; Musser, J; Navarra, G; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; D'Ettorre-Piazzoli, B; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Saavedra, O; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Stamerra, A; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Trinchero, G C; Vakili, M; Valchierotti, S; Vallania, P; Vernetto, S; Vigorito, C; Walter, C W; Webb, R; 10.1016/j.astropartphys.2004.01.005

2004-01-01

The primary cosmic ray (CR) proton, helium and CNO fluxes in the energy range 80-300 TeV are studied at the National Gran Sasso Laboratories by means of EAS-TOP (Campo Imperatore, 2005 m a.s.l.) and MACRO (deep underground, 3100 m w.e., the surface energy threshold for a muon reaching the detector being E/sub mu //sup th/ approximately=1.3 TeV). The measurement is based on: (a) the selection of primaries based on their energy/nucleon (i.e., with energy/nucleon sufficient to produce a muon with energy larger than 1.3 TeV) and the reconstruction of the shower geometry by means of the muons recorded by MACRO in the deep underground laboratories; (b) the detection of the associated atmospheric Cherenkov light (C.l.) signals by means of the C.l. detector of EAS-TOP. The C.l. density at core distance r>100 m is directly related to the total primary energy E/sub 0/. Proton and helium ("p+He") and proton, helium and CNO ("p +He+CNO") primaries are thus selected at E/sub 0/ approximately=80 Te V, and at E/sub 0/ appro...

The AMIGA enhancement of the Pierre Auger Observatory

Science.gov (United States)

Maldera, S.

2014-06-01

The AMIGA (Auger Muons and Infill for the Ground Array) enhancement of the Auger Surface Detector consists of a 23.5 km2 infill area instrumented with water-Cherenkov detector stations accompanied by 30 m2 of scintillator counters, buried 2.3 m underground. The spacing of 750 m between the surface detectors extends the energy range as low as 3 × 1017 eV, thus allowing the study of the energy region where the transition between galactic and extra-galactic cosmic rays is expected to take place. We describe the reconstruction of the events observed with the infill water-Cherenkov detector array and the derived energy spectrum. We also discuss the basic properties of the muon detector modules obtained from measurements and tests during the construction phase and from the first data in the field.

Water-Tree Modelling and Detection for Underground Cables

Science.gov (United States)

Chen, Qi

In recent years, aging infrastructure has become a major concern for the power industry. Since its inception in early 20th century, the electrical system has been the cornerstone of an industrial society. Stable and uninterrupted delivery of electrical power is now a base necessity for the modern world. As the times march-on, however, the electrical infrastructure ages and there is the inevitable need to renew and replace the existing system. Unfortunately, due to time and financial constraints, many electrical systems today are forced to operate beyond their original design and power utilities must find ways to prolong the lifespan of older equipment. Thus, the concept of preventative maintenance arises. Preventative maintenance allows old equipment to operate longer and at better efficiency, but in order to implement preventative maintenance, the operators must know minute details of the electrical system, especially some of the harder to assess issues such water-tree. Water-tree induced insulation degradation is a problem typically associated with older cable systems. It is a very high impedance phenomenon and it is difficult to detect using traditional methods such as Tan-Delta or Partial Discharge. The proposed dissertation studies water-tree development in underground cables, potential methods to detect water-tree location and water-tree severity estimation. The dissertation begins by developing mathematical models of water-tree using finite element analysis. The method focuses on surface-originated vented tree, the most prominent type of water-tree fault in the field. Using the standard operation parameters of North American electrical systems, the water-tree boundary conditions are defined. By applying finite element analysis technique, the complex water-tree structure is broken down to homogeneous components. The result is a generalized representation of water-tree capacitance at different stages of development. The result from the finite element analysis

Using Deep Learning for Gamma Ray Source Detection at the First G-APD Cherenkov Telescope (FACT)

Science.gov (United States)

Bieker, Jacob

2018-06-01

Finding gamma-ray sources is of paramount importance for Imaging Air Cherenkov Telescopes (IACT). This study looks at using deep neural networks on data from the First G-APD Cherenkov Telescope (FACT) as a proof-of-concept of finding gamma-ray sources with deep learning for the upcoming Cherenkov Telescope Array (CTA). In this study, FACT’s individual photon level observation data from the last 5 years was used with convolutional neural networks to determine if one or more sources were present. The neural networks used various architectures to determine which architectures were most successful in finding sources. Neural networks offer a promising method for finding faint and extended gamma-ray sources for IACTs. With further improvement and modifications, they offer a compelling method for source detection for the next generation of IACTs.

NECTAr: New electronics for the Cherenkov Telescope Array

International Nuclear Information System (INIS)

Vorobiov, S.; Bolmont, J.; Corona, P.; Delagnes, E.; Feinstein, F.; Gascon, D.; Glicenstein, J.-F.; Naumann, C.L.; Nayman, P.; Sanuy, A.; Toussenel, F.; Vincent, P.

2011-01-01

The European astroparticle physics community aims to design and build the next generation array of Imaging Atmospheric Cherenkov Telescopes (IACTs), that will benefit from the experience of the existing H.E.S.S. and MAGIC detectors, and further expand the very-high energy astronomy domain. In order to gain an order of magnitude in sensitivity in the 10 GeV to >100TeV range, the Cherenkov Telescope Array (CTA) will employ 50-100 mirrors of various sizes equipped with 1000-4000 channels per camera, to be compared with the 6000 channels of the final H.E.S.S. array. A 3-year program, started in 2009, aims to build and test a demonstrator module of a generic CTA camera. We present here the NECTAr design of front-end electronics for the CTA, adapted to the trigger and data acquisition of a large IACTs array, with simple production and maintenance. Cost and camera performances are optimized by maximizing integration of the front-end electronics (amplifiers, fast analog samplers, ADCs) in an ASIC, achieving several GS/s and a few μs readout dead-time. We present preliminary results and extrapolated performances from Monte Carlo simulations.

NECTAr: New electronics for the Cherenkov Telescope Array

Energy Technology Data Exchange (ETDEWEB)

Vorobiov, S., E-mail: vorobiov@lpta.in2p3.f [LPTA, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Bolmont, J.; Corona, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France); Delagnes, E. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Feinstein, F. [LPTA, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Gascon, D. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Glicenstein, J.-F. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Naumann, C.L.; Nayman, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France); Sanuy, A. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Toussenel, F.; Vincent, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France)

2011-05-21

The European astroparticle physics community aims to design and build the next generation array of Imaging Atmospheric Cherenkov Telescopes (IACTs), that will benefit from the experience of the existing H.E.S.S. and MAGIC detectors, and further expand the very-high energy astronomy domain. In order to gain an order of magnitude in sensitivity in the 10 GeV to >100TeV range, the Cherenkov Telescope Array (CTA) will employ 50-100 mirrors of various sizes equipped with 1000-4000 channels per camera, to be compared with the 6000 channels of the final H.E.S.S. array. A 3-year program, started in 2009, aims to build and test a demonstrator module of a generic CTA camera. We present here the NECTAr design of front-end electronics for the CTA, adapted to the trigger and data acquisition of a large IACTs array, with simple production and maintenance. Cost and camera performances are optimized by maximizing integration of the front-end electronics (amplifiers, fast analog samplers, ADCs) in an ASIC, achieving several GS/s and a few {mu}s readout dead-time. We present preliminary results and extrapolated performances from Monte Carlo simulations.

The use the a high intensity neutrino beam from the ESS proton linac for measurement of neutrino CP violation and mass hierarchy

CERN Document Server

Baussan, E.; Ekelof, T.; Martinez, E.Fernandez; Ohman, H.; Vassilopoulos, N.

2012-01-01

It is proposed to complement the ESS proton linac with equipment that would enable the production, concurrently with the production of the planned ESS beam used for neutron production, of a 5 MW beam of 10$^{23}$ 2.5 GeV protons per year in microsecond short pulses to produce a neutrino Super Beam, and to install a megaton underground water Cherenkov detector in a mine to detect $\

Development of an underwater high sensitivity Cherenkov detector: Sea Urchin

International Nuclear Information System (INIS)

Camerini, U.; McGibney, D.; Roberts, A.

1982-01-01

The need for a high gain, high sensitivity Cherenkov light sensor to be used in a deep underwater muon and neutrino detector (DUMAND) array has led to the design of the Sea Urchin detector. In this design a spherical photocathode PMTis optically coupled through a glass hemisphere to a large number of glass spines, each of which is filled with a wavelength-shifting (WLS) solution of a high quantum efficiency phosphor. The Cherenkov radiation is absorbed in the spine, isotropically re-radiated at a longer wavelength, and a fraction of the fluorescent light is internally reflected in the spine, and guided to the photomultiplier concentrically located in the glass hemisphere. Experiments measuring the optical characteristics of the spines and computer programs simulating light transformation and detection cross sections are described. Overall optical gains in the range 5-10 are achieved. The WLS solution is inexpensive, and may have other applications. (orig.)

MO-A-BRD-06: In Vivo Cherenkov Video Imaging to Verify Whole Breast Irradiation Treatment

Energy Technology Data Exchange (ETDEWEB)

Zhang, R; Glaser, A [Dartmouth College, Hanover, NH - New Hampshire (United States); Jarvis, L [Dartmouth-Hitchcock Medical Center, City Of Lebanon, New Hampshire (United States); Gladstone, D [Dartmouth-Hitchcock Medical Center, Hanover, City of Lebanon (Lebanon); Andreozzi, J; Hitchcock, W; Pogue, B [Dartmouth College, Hanover, NH (United States)

2014-06-15

Purpose: To show in vivo video imaging of Cherenkov emission (Cherenkoscopy) can be acquired in the clinical treatment room without affecting the normal process of external beam radiation therapy (EBRT). Applications of Cherenkoscopy, such as patient positioning, movement tracking, treatment monitoring and superficial dose estimation, were examined. Methods: In a phase 1 clinical trial, including 12 patients undergoing post-lumpectomy whole breast irradiation, Cherenkov emission was imaged with a time-gated ICCD camera synchronized to the radiation pulses, during 10 fractions of the treatment. Images from different treatment days were compared by calculating the 2-D correlations corresponding to the averaged image. An edge detection algorithm was utilized to highlight biological features, such as the blood vessels. Superficial dose deposited at the sampling depth were derived from the Eclipse treatment planning system (TPS) and compared with the Cherenkov images. Skin reactions were graded weekly according to the Common Toxicity Criteria and digital photographs were obtained for comparison. Results: Real time (fps = 4.8) imaging of Cherenkov emission was feasible and feasibility tests indicated that it could be improved to video rate (fps = 30) with system improvements. Dynamic field changes due to fast MLC motion were imaged in real time. The average 2-D correlation was about 0.99, suggesting the stability of this imaging technique and repeatability of patient positioning was outstanding. Edge enhanced images of blood vessels were observed, and could serve as unique biological markers for patient positioning and movement tracking (breathing). Small discrepancies exists between the Cherenkov images and the superficial dose predicted from the TPS but the former agreed better with actual skin reactions than did the latter. Conclusion: Real time Cherenkoscopy imaging during EBRT is a novel imaging tool that could be utilized for patient positioning, movement tracking

Stability and linearity control of spectrometric channels of the Cherenkov counters using controllable units

International Nuclear Information System (INIS)

Kollar, D.; Kollarova, L.; Khorvat, P.

1976-01-01

A system is elaborated to control stability and linearity of the Cherenkov counter spectrometric channels in an experiment on a magnetic monopole search. Linearity of a light characteristic of a photoelectric multiplier is checked with the help of the calibrated light-strikings of light emitting diodes with flare intensity adjusted by controlling generator voltage across the mercury body. A program algorithm is presented for checking stability and linearity of the Cherenkov counter spectrometric channels which helps to consider the fatigue effects of the photoelectric multiplier resulting from the considerable loads

Lunar imaging and ionospheric calibration for the Lunar Cherenkov technique

NARCIS (Netherlands)

McFadden, R.; Scholten, O.; Mevius, M.

2013-01-01

The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the

Optical Cherenkov radiation by cascaded nonlinear interaction: an efficient source of few-cycle energetic near- to mid-IR pulses

DEFF Research Database (Denmark)

Bache, Morten; Bang, Ole; Zhou, Binbin

2011-01-01

When ultrafast noncritical cascaded second-harmonic generation of energetic femtosecond pulses occur in a bulk lithium niobate crystal optical Cherenkov waves are formed in the near- to mid-IR. Numerical simulations show that the few-cycle solitons radiate Cherenkov (dispersive) waves in the λ = 2...

[Impact of Rocky Desertification Treatment on Underground Water Chemistry and Dissolved Inorganic Carbon Isotope in Karst Areas].

Science.gov (United States)

Xiao, Shi-zhen; Xiong, Kang-ning; Lan, Jia-cheng; Zhang, Hui; Yang, Long

2015-05-01

Five springs representing different land-use types and different karst rocky desertification treatment models were chosen at the Huajiang Karst Rocky Desertification Treatment Demonstration Site in Guanling-Zhenfeng Counties in Guizhou, to analyze the features of underground water chemistry and dissolved inorganic carbon isotopes (δ13C(DIC)) and reveal the effect of rocky desertification treatment on karstification and water quality. It was found that, the underground water type of the research area was HCO3-Ca; the water quality of the springs which were relatively less affected by human activities including Shuijingwan Spring (SJW) , Gebei Spring (GB), and Maojiawan Spring (MJW) was better than those relatively more affected by human activities including Diaojing Spring (DJ) and Tanjiazhai Spring (TJZ) , the main ion concentrations and electrical conductivity of which were higher; pH, SIc and pCO2 were sensitive to land-use types and rocky desertification treatment, which could be shown by the higher pH and SIc and lower pCO2 in MJW than those in the other four springs; (Ca(2+) + Mg2+)/HCO(3-) of SJW, MJW and GB were nearly 1:1, dominated by carbonate rock weathering by carbon acid, while the (Ca(2+) + Mg2+) of DJ and TJZ was much higher than HCO3-, suggesting that sulfate and nitrate might also dissolve carbonate rock because of the agricultural activities; δ13C(DIC) was lighter in wet season because of the higher biological activities; the average δ13C(DIC) was in the order of DJ (-12.79 per thousand) desertification and lighter after the rocky desertification are treated and controlled.

Dynamic underground stripping. Innovative technology summary report

International Nuclear Information System (INIS)

1995-04-01

Dynamic Underground Stripping (DUS) is a combination of technologies targeted to remediate soil and ground water contaminated with organic compounds. DUS is effective both above and below the water table and is especially well suited for sites with interbedded sand and clay layers. The main technologies comprising DUS are steam injection at the periphery of a contaminated area to heat permeable subsurface areas, vaporize volatile compounds bound to the soil, and drive contaminants to centrally located vacuum extraction wells; electrical heating of less permeable sediments to vaporize contaminants and drive them into the steam zone; and underground imaging such as Electrical Resistance Tomography to delineate heated areas to ensure total cleanup and process control. A full-scale demonstration was conducted on a gasoline spill site at Lawrence Livermore National Laboratory in Livermore, California from November 1992 through December 1993

The On-Site Analysis of the Cherenkov Telescope Array

CERN Document Server

Bulgarelli, Andrea; Zoli, Andrea; Aboudan, Alessio; Rodríguez-Vázquez, Juan José; De Cesare, Giovanni; De Rosa, Adriano; Maier, Gernot; Lyard, Etienne; Bastieri, Denis; Lombardi, Saverio; Tosti, Gino; Bergamaschi, Sonia; Beneventano, Domenico; Lamanna, Giovanni; Jacquemier, Jean; Kosack, Karl; Antonelli, Lucio Angelo; Boisson, Catherine; Borkowski, Jerzy; Buson, Sara; Carosi, Alessandro; Conforti, Vito; Colomé, Pep; Reyes, Raquel de los; Dumm, Jon; Evans, Phil; Fortson, Lucy; Fuessling, Matthias; Gotz, Diego; Graciani, Ricardo; Gianotti, Fulvio; Grandi, Paola; Hinton, Jim; Humensky, Brian; Inoue, Susumu; Knödlseder, Jürgen; Flour, Thierry Le; Lindemann, Rico; Malaguti, Giuseppe; Markoff, Sera; Marisaldi, Martino; Neyroud, Nadine; Nicastro, Luciano; Ohm, Stefan; Osborne, Julian; Oya, Igor; Rodriguez, Jerome; Rosen, Simon; Ribo, Marc; Tacchini, Alessandro; Schüssler, Fabian; Stolarczyk, Thierry; Torresi, Eleonora; Testa, Vincenzo; Wegner, Peter

2015-01-01

The Cherenkov Telescope Array (CTA) observatory will be one of the largest ground-based very high-energy gamma-ray observatories. The On-Site Analysis will be the first CTA scientific analysis of data acquired from the array of telescopes, in both northern and southern sites. The On-Site Analysis will have two pipelines: the Level-A pipeline (also known as Real-Time Analysis, RTA) and the level-B one. The RTA performs data quality monitoring and must be able to issue automated alerts on variable and transient astrophysical sources within 30 seconds from the last acquired Cherenkov event that contributes to the alert, with a sensitivity not worse than the one achieved by the final pipeline by more than a factor of 3. The Level-B Analysis has a better sensitivity (not be worse than the final one by a factor of 2) and the results should be available within 10 hours from the acquisition of the data: for this reason this analysis could be performed at the end of an observation or next morning. The latency (in part...

Moura tragedy the model for this year's underground exercise

Energy Technology Data Exchange (ETDEWEB)

1991-10-01

Mines Rescue teams in the 1991 E.K. Healy cup competition handled an underground exercise based on the Moura No. 4 colliery explosion which killed 12 miners on July 16, 1986. The contest organisers and hosts went to great lengths to achieve realism. This included underground water barriers and ventilation tubes being tossed around, meat, offal and bullock's blood being strewn and using trickel dusters to produce a smoke effect restricting visibility to 20 metres. The other exercises in the contest were: a theory test; and exercise involving gas monitoring, power isolation and fire fighting; and a first aid section dealt with an electrical accident near water. The task in the underground exercise was to retrieve information. The Chairman of the Assessors reported that the theory and fire fighting were handled fairly well. Handling of the electrical incident was not too bad, with the life saving techniques being very well done. The underground exercise revealed different ways of gathering information. While leadership styles and team member interaction varied this was not detrimental to efficiency. 9 photos.

Single-Cycle Terahertz Pulse Generation from OH1 Crystal via Cherenkov Phase Matching

Science.gov (United States)

Uchida, Hirohisa; Oota, Kengo; Okimura, Koutarou; Kawase, Kodo; Takeya, Kei

2018-06-01

OH1 crystal is an organic nonlinear optical crystal with a large nonlinear optical constant. However, it has dispersion of refractive indices in the terahertz (THz) frequency. This limits the frequencies that satisfy the phase matching conditions for THz wave generation. In this study, we addressed the phase matching conditions for THz wave generation by combining an OH1 crystal with prism-coupled Cherenkov phase matching. We observed the generation of single-cycle THz pulses with a spectrum covering a frequency range of 3 THz. These results prove that combining prism-coupled Cherenkov phase matching with nonlinear optical crystals yields a THz wave generation method that is insusceptible to crystal dispersion.

Underground storage tanks

International Nuclear Information System (INIS)

Anon.

1993-01-01

Environmental contamination from leaking underground storage tanks poses a significant threat to human health and the environment. An estimated five to six million underground storage tanks containing hazardous substances or petroleum products are in use in the US. Originally placed underground as a fire prevention measure, these tanks have substantially reduced the damages from stored flammable liquids. However, an estimated 400,000 underground tanks are thought to be leaking now, and many more will begin to leak in the near future. Products released from these leaking tanks can threaten groundwater supplies, damage sewer lines and buried cables, poison crops, and lead to fires and explosions. As required by the Hazardous and Solid Waste Amendments (HSWA), the EPA has been developing a comprehensive regulatory program for underground storage tanks. The EPA proposed three sets of regulations pertaining to underground tanks. The first addressed technical requirements for petroleum and hazardous substance tanks, including new tank performance standards, release detection, release reporting and investigation, corrective action, and tank closure. The second proposed regulation addresses financial responsibility requirements for underground petroleum tanks. The third addressed standards for approval of state tank programs

Underground pipeline corrosion

CERN Document Server

Orazem, Mark

2014-01-01

Underground pipelines transporting liquid petroleum products and natural gas are critical components of civil infrastructure, making corrosion prevention an essential part of asset-protection strategy. Underground Pipeline Corrosion provides a basic understanding of the problems associated with corrosion detection and mitigation, and of the state of the art in corrosion prevention. The topics covered in part one include: basic principles for corrosion in underground pipelines, AC-induced corrosion of underground pipelines, significance of corrosion in onshore oil and gas pipelines, n

Hydrogeologic study and underground drainage test; Estudio Hidrogeologico y Ensayo de Drenaje de Labores

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

Pauline mine belongs to the company Minero Siderurgica de Ponferrada, S. A., and is an underground mountain mine located in west area of Villablino colliery, in the north of Spain. Water invasion caused serious troubles in faces when the working level went deeper, in the new mining areas. In order to get control on this problems, the present HYDROGEOLOGIC STUDY AND UNDERGROUND DRAINAGE TEST was carry out, with the double aim of quantifying the amount of water to be pumped in future and of minimizing the undesirable effects of water invasions in underground mining. The development of the hydrogeologic study states some alternative solutions for draining, focusing on a reliable forecasting of the quantity of water to be exhausted and the means to be undertaken in order to minimize pump costs. These options were technically and economically evaluated and the more feasible recommended.

Horonobe underground research program. Research report of 2002 FY investigation

International Nuclear Information System (INIS)

2003-06-01

Main results of investigation about Horonobe deep underground research center in 2002 FY were reported. It consists of six chapters: introduction, main results, selection of research center area, underground science research, R and D of geological disposal, and the environmental survey and research center on the ground. The research center area at about 3 km north of Horonobe (B1) was selected in the four areas: A, B1, B2 and C on the basis of data, researches in the sky, aboveground and underground and other conditions. The model of geological environment was constructed by physical, geological, surface water supply researches. Development of geological environment monitoring techniques, investigation of long stabilization of geological environment and design of underground facilities are reported. The basic design of preparation of research center was investigated. (S.Y.)

Parametric Cherenkov radiation (development of idea)

International Nuclear Information System (INIS)

Buts, V.A.

2004-01-01

Some physical results of researches about charged particles radiation in mediums with a periodic heterogeneity and in periodic potential are reported. The development of ideas Parametric Cherenkov Radiation has shown, that in mediums, which have even a weak degree of a periodic heterogeneity of an permittivity or potential, the nonrelativistic oscillators can radiated as relativistic. They effectively radiate the high numbers of harmonics. In particular, in the carried out experiments the ultra-violet radiation was excited at action on a crystal of intensive ten-centimetric radiation. These results give the reasons to hope for making of nonrelativistic lasers on free electrons

Laboratory study on streaming potential for exploring underground water flow; Shitsunai jikken ni yoru ryudo den`i wo mochiita mizu michi tansa no kanosei no kento

Energy Technology Data Exchange (ETDEWEB)

Sato, H; Shima, H [Oyo Corp., Tokyo (Japan)

1997-05-27

To investigate a possibility of exploration of underground water flow as well as to grasp the underground fluid flow by measuring streaming potential at the ground surface, some experiments were conducted using a model unit by considering the difference of permeability. For this experimental unit, water is driven by adding head difference between the polyethylene vessel filled with water and the experimental water tank. The size of water tank is 350{times}160 mm with a height of 160 mm. Twenty platinum electrodes are set on the cover of water tank. Toyoura standard sand and Kanto loam were used for the experiments. For the experiments, fluid was injected in various combined models by considering the permeability, to measure the streaming potential. As a result, it was explained by the streaming potential that the fluid flows in a form of laminar flow in the experimental water tank, and that the movement of fluid in the Kanto loam is quite slow. It was also confirmed that the streaming potential method is an effective technique for grasping the movement of fluid. 3 refs., 8 figs.

Large-area atmospheric Cherenkov detectors for high-energy gamma-ray astronomy

International Nuclear Information System (INIS)

Ong, R.A.

1996-01-01

This paper describes the development of new ground-based gamma-ray detectors to explore the energy region between 20 and 200 GeV. This region in energy is interesting because it is currently unexplored by any experiment. The proposed detectors use the atmospheric Cherenkov technique, in which Cherenkov radiation produced in the gamma-ray air showers is detected using mirrors and light-sensitive devices. The important feature of the proposed experiments is the use of large mirror collection areas, which should allow for a significant improvement (i.e. reduction) in energy threshold over existing experiments. Large mirror areas are available for relatively low cost at central tower solar power plants, and there are two groups developing gamma-ray experiments using solar heliostat arrays. This paper summarizes the progress in the design of experiments using this novel approach

Cherenkov radiation-based three-dimensional position-sensitive PET detector: A Monte Carlo study.

Science.gov (United States)

Ota, Ryosuke; Yamada, Ryoko; Moriya, Takahiro; Hasegawa, Tomoyuki

2018-05-01

Cherenkov radiation has recently received attention due to its prompt emission phenomenon, which has the potential to improve the timing performance of radiation detectors dedicated to positron emission tomography (PET). In this study, a Cherenkov-based three-dimensional (3D) position-sensitive radiation detector was proposed, which is composed of a monolithic lead fluoride (PbF 2 ) crystal and a photodetector array of which the signals can be readout independently. Monte Carlo simulations were performed to estimate the performance of the proposed detector. The position- and time resolution were evaluated under various practical conditions. The radiator size and various properties of the photodetector, e.g., readout pitch and single photon timing resolution (SPTR), were parameterized. The single photon time response of the photodetector was assumed to be a single Gaussian for the simplification. The photo detection efficiency of the photodetector was ideally 100% for all wavelengths. Compton scattering was included in simulations, but partly analyzed. To estimate the position at which a γ-ray interacted in the Cherenkov radiator, the center-of-gravity (COG) method was employed. In addition, to estimate the depth-of-interaction (DOI) principal component analysis (PCA), which is a multivariate analysis method and has been used to identify the patterns in data, was employed. The time-space distribution of Cherenkov photons was quantified to perform PCA. To evaluate coincidence time resolution (CTR), the time difference of two independent γ-ray events was calculated. The detection time was defined as the first photon time after the SPTR of the photodetector was taken into account. The position resolution on the photodetector plane could be estimated with high accuracy, by using a small number of Cherenkov photons. Moreover, PCA showed an ability to estimate the DOI. The position resolution heavily depends on the pitch of the photodetector array and the radiator

Measuring the emulsion stability in Cherenkov radiation with insignificant modification of a liquid scintillation spectrometer

International Nuclear Information System (INIS)

Wiechen, A.; Lorenzen, P.Ch.; Reimerdes, E.H.

1984-01-01

A method is described by which the stability of emulsions can be measured by a modified liquid scintillation counter. The 226 Ra external standard source of a commercially available equipment, fixed in the measuring position, is used for the production of Cherenkov radiation in a sample of an emulsion. This Cherenkov radiation is absorbed by the sample due to its turbidity. The turbidity of emulsions follows a typical course with time designated as creaming-up-curve. These curves can be registered automatically in digital form. (author)

Hydrogeologic study and underground drainage test; Estudio hidrogeologico y ensayo de drenaje de labores

Energy Technology Data Exchange (ETDEWEB)

1999-09-01

Pauline mine belongs to the company Minero Siderurgica de Ponferrada, S. A., and is an underground mountain mine located in west area of Villablino colliery, in the north of Spain. Water invasion caused serious troubles in faces when the working level went deeper, in the new mining areas. Water invasion caused serious troubles in faces the working level went deeper, in the new mining areas. In order to get control on this problems, the present Hydrogeologic Study and Underground Drainage Test was carry out, with the double aim of quantifying the amount of water to be pumped in future and of minimizing the undesirable effects of water invasions in underground mining. The development of the hydrogeologic study states some alternative solutions for draining, focussing on a reliable forecasting of the quantity of water to be exhausted and the means to be undertaken in order to minimize pump costs. These options were technically and economically evaluated and the more feasible recommended. (Author)

Quality Assurance of Pixel Hybrid Photon Detectors for the LHCb Ring Imaging Cherenkov Counters

CERN Document Server

Carson, Laurence

Pion/kaon discrimination in the LHCb experiment will be provided by two Ring Imaging Cherenkov (RICH) counters. These use arrays of 484 Hybrid Photon Detectors (HPDs) to detect the Cherenkov photons emitted by charged particles traversing the RICH. The results from comprehensive quality assurance tests on the 550 HPDs manufactured for LHCb are described. Leakage currents, dead channel probabilities, dark count rates and ion feedback rates are reported. Furthermore, measurements carried out on a sample of tubes to determine the efficiency of the HPD pixel chip by measuring the summed analogue response from the backplane of the silicon sensor are described.

COSTEAU - preheating and cooling by means of underground collectors with water circulation - case study (Perret building at Satigny, Geneva) and generalisation; COSTEAU. Prechauffage et rafraichissement par collecteurs souterrains a eau. Etude de cas (batiment Perret a Satigny, Geneve) et generalisation

Energy Technology Data Exchange (ETDEWEB)

Hollmuller, P.; Lachal, B.

2003-07-01

Since a couple of years, underground collectors with air circulation have been becoming increasingly popular as a simple means for preheating (at winter time) and cooling (at summer time) of outdoor air ahead of a ventilation system for well insulated buildings. This report considers underground collectors with water circulation used for similar purposes. They are connected to the ventilation system via an air/water heat exchanger. Starting from a case study - one-year detailed in-situ measurements and data analysis from an air-heated office building near Geneva, Switzerland - computerised simulations have been performed as a sensitivity analysis tool as well as to establish recommendations and sizing rules for planners, including cost considerations. In the case study it turned out that the water-circulated underground collector, which is installed right under the basement of this well insulated building, is in thermal contact with the basement. Its main function is to damp the daily temperature oscillation of the inlet ventilation air, bringing the expected thermal comfort improvement in the summer time. However, this underground collector is unable to collect seasonally stored heat from the ground. Hence, in the winter time the main preheating contribution arises from the series-connected heat-recovery unit from the exit air. Numerical simulations show that optimal sizing of underground collectors is essential, and that both the underground collector and the well insulated building as a physical system with thermal inertia have to be simultaneously considered in the optimization process. Optimization also has to include parasitic energy (electricity) needed by fans and pumps. As outdoor air inlet can never be flooded in the case of underground collectors with water circulation the sanitary risk encountered with air-circulated underground collectors does not exist for them. Initial investment cost for water-circulated underground collectors is higher than for a

Application of tritium content isotopic measurements to the investigation of underground water circulations and mixing in different porous media

International Nuclear Information System (INIS)

Leguy, C.

1979-06-01

This research thesis aims at investigating actual and potential mixing of underground waters in different soil types, and more particularly different porous media. Tritium content measurements of these waters have been performed by liquid scintillation after enrichment. The first part of this report addresses the physical aspect of these measurements. The second one deals with the interpretation of the acquired data, of circulation or mixing schemes which can be deduced with respect to the concerned soils. It highlights the importance of geo-morphological factors for the studied flows

TH-CD-201-04: A Study of Cherenkov Light Generated and Collected in Plastic Scintillation Detector

Energy Technology Data Exchange (ETDEWEB)

Archambault, L [CHUQ Pavillon Hotel-Dieu de Quebec, Quebec, QC (Canada); Papaconstadopoulos, P [McGill Montreal General Hospital, Montreal, QC (Canada); Seuntjens, J [McGill Montreal General Hospital, Montreal, QC (Canada); McGill University, Montreal, Quebec (Canada); Bouchard, H [CHUM-Hospital Notre-Dame, Montreal, QC (Canada)

2016-06-15

Purpose: To study Cherenkov light emission in plastic scintillation detectors (PSDs) from a theoretical point of view to identify situations that may arise where the calibration coefficient obtained in one condition is not applicable to another condition. By identifying problematic situations, we hope to provide guidance on how to confidently use PSDs. Methods: Cherenkov light emission in PSD was modelled using basic physical principles. In particular, changes in refractive index as a function of wavelength were accounted for using the Sellmeier empirical equation. Both electron and photon beams were considered. For photons, realistic distributions of secondary charged particles were calculated using Klein-Nishina’s formula. Cherenkov production and collection in PSDs were studied for a range of parameters including beam energy, charged particle momentum distribution, detector orientation and material composition. Finally, experimental validation was made using a commercial plastic scintillation detector. Results: In specific situations, results show that the Cherenkov spectrum coupled in the PSD can deviate from its expected behaviour (i.e. one over the square of the wavelength). In these cases were the model is realistic it is possible to see a peak wavelength instead of a monotonically decreasing function. Consequences of this phenomenon are negligible when the momentum of charged particle is distributed randomly, but in some clinically relevant cases, such as an electron beam at depth close to R50 or for photon beams with minimal scatter component, the value of the calibration coefficient can be altered. Experimental tests with electron beams showed changes in the Cherenkov light ratio, the parameter used in the calibration of PSDs, up to 2–3% depending on the PSD orientation. Conclusion: This work is the first providing a physical explanation for apparent change in PSD calibration coefficient. With this new information at hand, it will be possible to

The Canfranc Underground Laboratory

International Nuclear Information System (INIS)

Amare, J.; Beltran, B.; Carmona, J.M.; Cebrian, S.; Garcia, E.; Irastorza, I.G.; Gomez, H.; Luzon, G.; Martinez, M.; Morales, J.; Ortiz de Solorzano, A.; Pobes, C.; Puimedon, J.; Rodriguez, A.; Ruz, J.; Sarsa, M.L.; Torres, L.; Villar, J.A.

2005-01-01

This paper describes the forthcoming enlargement of the Canfranc Underground Laboratory (LSC) which will allow to host new international Astroparticle Physics experiments and therefore to broaden the European underground research area. The new Canfranc Underground Laboratory will operate in coordination (through the ILIAS Project) with the Gran Sasso (Italy), Modane (France) and Boulby (UK) underground laboratories

CELESTE: an atmospheric Cherenkov telescope for high energy gamma astrophysics

Czech Academy of Sciences Publication Activity Database

Paré, E.; Balauge, B.; Bazer-Bachi, R.; Bergeret, H.; Berny, F.; Briand, N.; Bruel, P.; Cerutti, M.; Collon, J.; Cordier, A.; Cornbise, P.; Debiais, G.; Dezalay, J. P.; Dumora, D.; Durand, E.; Eschstruth, P.; Espigat, P.; Fabre, B.; Fleury, P.; Gilly, J.; Gouillaud, J. C.; Gregory, C.; Hérault, N.; Holder, J.; Hrabovský, Miroslav; Incerti, S.; Jouenne, A.; Kalt, L.; LeGallou, R.; Lott, B.; Manigot, P.; Neveu, J.; Olive, J. F.; Palatka, Miroslav; Perez, A.; Rebii, A.; Rob, L.; Sans, J. L.; Schovánek, Petr; Villard, G.

2002-01-01

Roč. 490, - (2002), s. 71-89 ISSN 0168-9002 R&D Projects: GA MŠk LN00A006 Institutional research plan: CEZ:AV0Z1010920 Keywords : gamma-ray astronopy * atmospheric Cherenkov detector Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.167, year: 2002

Development of a mid-sized Schwarzschild-Couder Telescope for the Cherenkov Telescope Array

Energy Technology Data Exchange (ETDEWEB)

Cameron, Robert A.

2012-06-28

The Cherenkov Telescope Array (CTA) is a ground-based observatory for very high-energy (10 GeV to 100 TeV) gamma rays, planned for operation starting in 2018. It will be an array of dozens of optical telescopes, known as Atmospheric Cherenkov Telescopes (ACTs), of 8 m to 24 m diameter, deployed over an area of more than 1 square km, to detect flashes of Cherenkov light from showers initiated in the Earth's atmosphere by gamma rays. CTA will have improved angular resolution, a wider energy range, larger fields of view and an order of magnitude improvement in sensitivity over current ACT arrays such as H.E.S.S., MAGIC and VERITAS. Several institutions have proposed a research and development program to eventually contribute 36 medium-sized telescopes (9 m to 12 m diameter) to CTA to enhance and optimize its science performance. The program aims to construct a prototype of an innovative, Schwarzschild-Couder telescope (SCT) design that will allow much smaller and less expensive cameras and much larger fields of view than conventional Davies-Cotton designs, and will also include design and testing of camera electronics for the necessary advances in performance, reliability and cost. We report on the progress of the mid-sized SCT development program.

R and D on high momentum particle identification with a pressurized Cherenkov radiator

Energy Technology Data Exchange (ETDEWEB)

Agócs, A.G. [Wigner RCP of the HAS, Budapest (Hungary); Barile, F. [INFN Sezione di Bari and Universit´a degli Studi di Bari, Dipartimento Interateneo di Fisica M. Merlin, Bari (Italy); Barnaföldi, G.G. [Wigner RCP of the HAS, Budapest (Hungary); Bellwied, R. [University of Houston, Houston (United States); Bencédi, G.; Bencze, G.; Berényi, D.; Boldizsár, L. [Wigner RCP of the HAS, Budapest (Hungary); Chattopadhyay, S. [Saha Institute of Nuclear Physics, Kolkata (India); Chinellato, D.D. [University of Houston, Houston (United States); Cindolo, F. [University of Salerno, Salerno (Italy); Cossyleon, K. [Chicago State University, Chicago, IL (United States); Das, D.; Das, K.; Das-Bose, L. [Saha Institute of Nuclear Physics, Kolkata (India); De Cataldo, G.; Di Bari, D. [INFN Sezione di Bari and Universit´a degli Studi di Bari, Dipartimento Interateneo di Fisica M. Merlin, Bari (Italy); Di Mauro, A. [CERN, CH1211 Geneva 23 (Switzerland); Futó, E. [Wigner RCP of the HAS, Budapest (Hungary); Garcia-Solis, E. [Chicago State University, Chicago, IL (United States); and others

2014-12-01

We report on the R and D results for a Very High Momentum Particle Identification (VHMPID) detector, which was proposed to extend the charged hadron track-by-track identification in the momentum range from 5 to 25 GeV/c in the ALICE experiment at CERN. It is a RICH detector with focusing geometry using pressurized perfluorobutane (C{sub 4}F{sub 8}O) as a Cherenkov radiator. A MWPC with a CsI photocathode was investigated as the baseline option for the photon detector. The results of beam tests performed on RICH prototypes using both liquid C{sub 6}F{sub 14} radiator (in proximity focusing geometry for reference measurements) and pressurized C{sub 4}F{sub 8}O gaseous radiator will be shown in this paper. In addition, we present studies of a CsI based gaseous photon detector equipped with a MWPC having an adjustable anode–cathode gap, aiming at the optimization of the chamber layout and performance in the detection of single photoelectrons. - Highlights: • Pressurized and heated C{sub 4}F{sub 8}O was used as Cherenkov radiator gas. • A Cherenkov angle resolution of 1.5 mrad was achieved. • The separation of electrons, pions, and kaons in a large momentum range is shown.

Design and fabrication of a window for the gas Cherenkov detector 3

Energy Technology Data Exchange (ETDEWEB)

Fatherley, V. E., E-mail: vef@lanl.gov; Bingham, D. A.; Cartelli, M. D.; Griego, J. R.; Herrmann, H. W.; Lopez, F. E.; Oertel, J. A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); DiDomizio, R. A.; Pollack, M. J. [EnvirOptics, Inc., Colmar, Pennsylvania 18915 (United States)

2016-11-15

The gas Cherenkov detector 3 was designed at Los Alamos National Laboratory for use in inertial confinement fusion experiments at both the Omega Laser Facility and the National Ignition Facility. This instrument uses a low-Z gamma-to-electron convertor plate and high pressure gas to convert MeV gammas into UV/visible Cherenkov photons for fast optical detection. This is a follow-on diagnostic from previous versions, with two notable differences: the pressure of the gas is four times higher, and it allows the use of fluorinated gas, requiring metal seals. These changes force significant changes in the window component, having a unique set of requirements and footprint limitations. The selected solution for this component, a sapphire window brazed into a stainless steel flange housing, is described.

Design study of underground facility of the Underground Research Laboratory

International Nuclear Information System (INIS)

Hibiya, Keisuke; Akiyoshi, Kenji; Ishizuka, Mineo; Anezaki, Susumu

1998-03-01

Geoscientific research program to study deep geological environment has been performed by Power Reactor and Nuclear Fuel Development Corporation (PNC). This research is supported by 'Long-Term Program for Research, Development and Utilization of Nuclear Energy'. An Underground Research Laboratory is planned to be constructed at Shoma-sama Hora in the research area belonging to PNC. A wide range of geoscientific research and development activities which have been previously studied at the Tono Area is planned in the laboratory. The Underground Research Laboratory is consisted of Surface Laboratory and Underground Research Facility located from the surface down to depth between several hundreds and 1,000 meters. Based on the results of design study in last year, the design study performed in this year is to investigate the followings in advance of studies for basic design and practical design: concept, design procedure, design flow and total layout. As a study for the concept of the underground facility, items required for the facility are investigated and factors to design the primary form of the underground facility are extracted. Continuously, design methods for the vault and the underground facility are summarized. Furthermore, design procedures of the extracted factors are summarized and total layout is studied considering the results to be obtained from the laboratory. (author)

Light output optimization for the Cherenkov strips of the Barrel detector of FOPI

Energy Technology Data Exchange (ETDEWEB)

Petrovici, M; Gobbi, A; Hildenbrand, K D [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Kirejczyk, M; Sikora, B [Warsaw Univ. (Poland); Chelepov, V; Dulin, M; Frolov, S; Judentsov, A; Krylov, V; Nikitin, A; Smolyankin, V; Zhilin, A [Institute for Theoretical and Expermental Physics - ITEP, B. Chermushkinskaya ulitsa 25, RU-117 259 Moskva, (Russian Federation); Mgebrishvili, G; Vasiliev, M [I.V. Kurchatov Institute of Atomic Energy, Ulitsa Kurchatova 46, RU-123 182 Moskva, (Russian Federation)

1994-12-31

Available as short communication only. A systematic study on how to increase the number of the photoelectrons (PE) in the phototubes at the end of the bent light guides has been undertaken prior to the final assembly of the Cherenkov strips of the Barrel detector for the 4{pi} facility FOPI at GSI-Darmstadt. This was motivated by the observation that with the mass-produced strips only 0.8 PE were found for cosmic rays incident at the center of the 240 cm long strips, a value too low to ensure a decent detection of even {beta}=1 particles. The method used was based on a careful calibration of the amplitude spectra by means of measuring single-electron peaks in the attached tubes. As the consequence of these studies the wave-length shifter (amino G salt) concentration in the distilled water of strips was optimized and a cell of 1000 mm with a mirror on one side has been used. These changes brought a improvement factor of 9 in the number of PE at 85 cm distance from the light guide. This results led to the decision of changing the former design of the Cherenkov layer. In addition during production of these final modules it has been observed that variances between different strips in terms of the number of PE could be minimized by an outer polishing of the plexiglas cells. Finally, during mounting of the detectors the used phototubes were selected according to their performance in peak to valley ratio of the single electron peaks spectrum. (Author) 3 Figs., 2 Refs.

Quality of underground water and hydro-geological situation caused by oil exploitation in the area of Kikinda

Directory of Open Access Journals (Sweden)

Pašić Milana

2010-01-01

Full Text Available Numerous oil fields were discovered in the area of North Banat and its regional centre, the city of Kikinda. These oil fields were explored and exploited in the second half of the XX century. Oil rigs in the area of the city zone can endanger the environment, as well as the quality of life of the citizens. In order to discover the presence of polycyclic aromatic hydrocarbon we have applied GC/MSD technique, whereas we have applied GC/MSD Purge and trap. technique to discover the presence of aromatic hydrocarbon. Chemical analyses of water samples from the area of Kikinda did nit prove that underground water was polluted with oil. .

BGO as a hybrid scintillator / Cherenkov radiator for cost-effective time-of-flight PET

Science.gov (United States)

Brunner, S. E.; Schaart, D. R.

2017-06-01

Due to detector developments in the last decade, the time-of-flight (TOF) method is now commonly used to improve the quality of positron emission tomography (PET) images. Clinical TOF-PET systems based on L(Y)SO:Ce crystals and silicon photomultipliers (SiPMs) with coincidence resolving times (CRT) between 325 ps and 400 ps FWHM have recently been developed. Before the introduction of L(Y)SO:Ce, BGO was used in many PET systems. In addition to a lower price, BGO offers a superior attenuation coefficient and a higher photoelectric fraction than L(Y)SO:Ce. However, BGO is generally considered an inferior TOF-PET scintillator. In recent years, TOF-PET detectors based on the Cherenkov effect have been proposed. However, the low Cherenkov photon yield in the order of  ˜10 photons per event complicates energy discrimination-a severe disadvantage in clinical PET. The optical characteristics of BGO, in particular its high transparency down to 310 nm and its high refractive index of  ˜2.15, are expected to make it a good Cherenkov radiator. Here, we study the feasibility of combining event timing based on Cherenkov emission with energy discrimination based on scintillation in BGO, as a potential approach towards a cost-effective TOF-PET detector. Rise time measurements were performed using a time-correlated single photon counting (TCSPC) setup implemented on a digital photon counter (DPC) array, revealing a prompt luminescent component likely to be due to Cherenkov emission. Coincidence timing measurements were performed using BGO crystals with a cross-section of 3 mm  ×  3 mm and five different lengths between 3 mm and 20 mm, coupled to DPC arrays. Non-Gaussian coincidence spectra with a FWHM of 200 ps were obtained with the 27 mm3 BGO cubes, while FWHM values as good as 330 ps were achieved with the 20 mm long crystals. The FWHM value was found to improve with decreasing temperature, while the FWTM value showed the opposite trend.

BGO as a hybrid scintillator / Cherenkov radiator for cost-effective time-of-flight PET.

Science.gov (United States)

Brunner, S E; Schaart, D R

2017-06-07

Due to detector developments in the last decade, the time-of-flight (TOF) method is now commonly used to improve the quality of positron emission tomography (PET) images. Clinical TOF-PET systems based on L(Y)SO:Ce crystals and silicon photomultipliers (SiPMs) with coincidence resolving times (CRT) between 325 ps and 400 ps FWHM have recently been developed. Before the introduction of L(Y)SO:Ce, BGO was used in many PET systems. In addition to a lower price, BGO offers a superior attenuation coefficient and a higher photoelectric fraction than L(Y)SO:Ce. However, BGO is generally considered an inferior TOF-PET scintillator. In recent years, TOF-PET detectors based on the Cherenkov effect have been proposed. However, the low Cherenkov photon yield in the order of  ∼10 photons per event complicates energy discrimination-a severe disadvantage in clinical PET. The optical characteristics of BGO, in particular its high transparency down to 310 nm and its high refractive index of  ∼2.15, are expected to make it a good Cherenkov radiator. Here, we study the feasibility of combining event timing based on Cherenkov emission with energy discrimination based on scintillation in BGO, as a potential approach towards a cost-effective TOF-PET detector. Rise time measurements were performed using a time-correlated single photon counting (TCSPC) setup implemented on a digital photon counter (DPC) array, revealing a prompt luminescent component likely to be due to Cherenkov emission. Coincidence timing measurements were performed using BGO crystals with a cross-section of 3 mm  ×  3 mm and five different lengths between 3 mm and 20 mm, coupled to DPC arrays. Non-Gaussian coincidence spectra with a FWHM of 200 ps were obtained with the 27 mm 3 BGO cubes, while FWHM values as good as 330 ps were achieved with the 20 mm long crystals. The FWHM value was found to improve with decreasing temperature, while the FWTM value showed the opposite

30 CFR 57.20031 - Blasting underground in hazardous areas.

Science.gov (United States)

2010-07-01

... METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL... dangerous accumulations of water, gas, mud, or fire atmosphere could be encountered, persons shall be...

First observation of Cherenkov rings with a large area CsI-TGEM-based RICH prototype

CERN Document Server

Peskov, V; Di Mauro, A; Martinengo, P; Mayani, D; Molnar, L; Nappi, E; Paic, G; Smirnov, N; Anand, H; Shukla, I

2012-01-01

We have built a RICH detector prototype consisting of a liquid C6F14 radiator and six triple Thick Gaseous Electron Multipliers (TGEMs), each of them having an active area of 10x10 cm2. One triple TGEM has been placed behind the liquid radiator in order to detect the beam particles, whereas the other five have been positioned around the central one at a distance to collect the Cherenkov photons. The upstream electrode of each of the TGEM stacks has been coated with a 0.4 micron thick CsI layer. In this paper, we will present the results from a series of laboratory tests with this prototype carried out using UV light, 6 keV photons from 55Fe and electrons from 90Sr as well as recent results of tests with a beam of charged pions where for the first time Cherenkov Ring images have been successfully recorded with TGEM photodetectors. The achieved results prove the feasibility of building a large area Cherenkov detector consisting of a matrix of TGEMs.

A Cherenkov imager for the charge measurement of the elements of nuclear cosmic radiation

International Nuclear Information System (INIS)

Sallaz-Damaz, Y.

2008-10-01

A Cherenkov imager, CHERCAM (Cherenkov Camera) has been designed and built for the CREAM (Cosmic Ray Energetics and Mass) balloon-borne experiment. The instrument will perform charge measurements of nuclear cosmic-ray over a range extending from proton to iron in the energy domain from 10 10 to 10 15 eV. This work has focused on the development of CHERCAM by creating a simulation of the detector and on the aerogel plan characterization for the radiator. But it has also expanded on the technical aspects of the construction of the detector and its various tests, as well as the development of calibration software and data analysis. (author)

Gaseous photomultipliers for the readout of scintillators and detection Cherenkov radiation

International Nuclear Information System (INIS)

Peskov, V.; Borovik-Romanov, A.

1993-11-01

The latest achievements in the development of gaseous detectors for registering UV and visible photons are described. Possible modifications of their design for some particular applications such as the readout of crystal scintillators. noble liquids, fibers and for large area Cherenkov detectors are discussed

Research on application of mobile diesel equipment in underground mines (IV)

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-01

This research commenced in 1994 for the purpose of providing safety and environmental measures of underground mines where the mobile diesel equipment are operating. In this last research year, researches on filtering of diesel particulate matter, design of underground layout and disaster prevention have been carried out. 1) A study to reduce DPM(Diesel Particulate Matter) emission: It was known that water scrubber is only one practical way to reduce DPM emission as of now. There are several kinds of the sophisticated DPM filters, but it is not practical yet to be used in underground equipment due to the many adverse effects of the devices such as tremendous increase of SOx, NOx and back pressure etc. 2) Design of underground layout and their maintenance: Layout of underground structure has to be designed based on rock mechanical analysis and the concept of active support has to be adopted considering the large openings are requested to accommodate heavy duty diesel equipment in underground. Rock bolt and shotcrete will be the most applicable method to support such a large dimensional tunnels. 3) A study for disaster prevention in the case of the underground fire: There are two categories of possible disaster or hazard in workings where diesel equipment are operating. One is the disasters by exhaust pollutants and the other is the underground fire. (author). 35 refs., 27 tabs., 56 figs.

The Cherenkov Telescope Array For Very High-Energy Astrophysics

Science.gov (United States)

Kaaret, Philip

2015-08-01

The field of very high energy (VHE) astrophysics had been revolutionized by the results from ground-based gamma-ray telescopes, including the current imaging atmospheric Cherenkov telescope (IACT) arrays: HESS, MAGIC and VERITAS. A worldwide consortium of scientists from 29 countries has formed to propose the Cherenkov Telescope Array (CTA) that will capitalize on the power of this technique to greatly expand the scientific reach of ground-based gamma-ray telescopes. CTA science will include key topics such as the origin of cosmic rays and cosmic particle acceleration, understanding extreme environments in regions close to neutron stars and black holes, and exploring physics frontiers through, e.g., the search for WIMP dark matter, axion-like particles and Lorentz invariance violation. CTA is envisioned to consist of two large arrays of Cherenkov telescopes, one in the southern hemisphere and one in the north. Each array will contain telescopes of different sizes to provide a balance between cost and array performance over an energy range from below 100 GeV to above 100 TeV. Compared to the existing IACT arrays, CTA will have substantially better angular resolution and energy resolution, will cover a much wider energy range, and will have up to an order of magnitude better sensitivity. CTA will also be operated as an open observatory and high-level CTA data will be placed into the public domain; these aspects will enable broad participation in CTA science from the worldwide scientific community to fully capitalize on CTA's potential. This talk will: 1) review the scientific motivation and capabilities of CTA, 2) provide an overview of the technical design and the status of prototype development, and 3) summarize the current status of the project in terms of its proposed organization and timeline. The plans for access to CTA data and opportunities to propose for CTA observing time will be highlighed.Presented on behalf of the CTA Consortium.

New air Cherenkov light detectors to study mass composition of cosmic rays with energies above knee region

Energy Technology Data Exchange (ETDEWEB)

Tsunesada, Yoshiki, E-mail: tsunesada@cr.phys.titech.ac.jp [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8550 Japan (Japan); Katsuya, Ryoichi, E-mail: katsuya@cr.phys.titech.ac.jp [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8550 Japan (Japan); Mitsumori, Yu; Nakayama, Keisuke; Kakimoto, Fumio; Tokuno, Hisao [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8550 Japan (Japan); Tajima, Norio [RIKEN, Wako, Saitama 351-0198 (Japan); Miranda, Pedro; Salinas, Juan; Tavera, Wilfredo [Instituto de Investigaciones Físicas, Universidad Mayor de San Andrés, La Paz (Bolivia, Plurinational State of)

2014-11-01

We have installed a hybrid detection system for air showers generated by cosmic rays with energies greater than 3×10{sup 15}eV at Mount Chacaltaya (5200 m above the sea level), in order to study the mass composition of cosmic rays above the knee region. This detection system comprises an air shower array with 49 scintillation counters in an area of 500 m×650 m, and seven new Cherenkov light detectors installed in a radial direction from the center of the air shower array with a separation of 50 m. It is known that the longitudinal development of a particle cascade in the atmosphere strongly depends on the type of the primary nucleus, and an air shower initiated by a heavier nucleus develops faster than that by a lighter primary of the same energy, because of the differences in the interaction cross-section and the energy per nucleon. This can be measured by detecting the Cherenkov radiation emitted from charged particles in air showers at higher altitudes. In this paper we describe the design and performance of our new non-imaging Cherenkov light detectors at Mount Chacaltaya that are operated in conjunction with the air shower array. The arrival directions and energies of air showers are determined by the shower array, and information about the primary masses is obtained from the Cherenkov light data including the time profiles and lateral distributions. The detector consists of photomultiplier tube (PMT), high-speed ADCs, other control modules, and data storage device. The Cherenkov light signals from an air shower are typically 10–100 ns long, and the waveforms are digitized with a sampling frequency of 1 GHz and recorded in situ without long-distance analog signal transfers. All the Cherenkov light detectors record their time-series data by receiving a triggering signal transmitted from the trigger module of the air shower array, which is fired by a coincidence of shower signals in four neighboring scintillation counters. The optical characteristics of the

A Web-Based GIS for Reporting Water Usage in the High Plains Underground Water Conservation District

Science.gov (United States)

Jia, M.; Deeds, N.; Winckler, M.

2012-12-01

The High Plains Underground Water Conservation District (HPWD) is the largest and oldest of the Texas water conservation districts, and oversees approximately 1.7 million irrigated acres. Recent rule changes have motivated HPWD to develop a more automated system to allow owners and operators to report well locations, meter locations, meter readings, the association between meters and wells, and contiguous acres. INTERA, Inc. has developed a web-based interactive system for HPWD water users to report water usage and for the district to better manage its water resources. The HPWD web management system utilizes state-of-the-art GIS techniques, including cloud-based Amazon EC2 virtual machine, ArcGIS Server, ArcSDE and ArcGIS Viewer for Flex, to support web-based water use management. The system enables users to navigate to their area of interest using a well-established base-map and perform a variety of operations and inquiries against their spatial features. The application currently has six components: user privilege management, property management, water meter registration, area registration, meter-well association and water use report. The system is composed of two main databases: spatial database and non-spatial database. With the help of Adobe Flex application at the front end and ArcGIS Server as the middle-ware, the spatial feature geometry and attributes update will be reflected immediately in the back end. As a result, property owners, along with the HPWD staff, collaborate together to weave the fabric of the spatial database. Interactions between the spatial and non-spatial databases are established by Windows Communication Foundation (WCF) services to record water-use report, user-property associations, owner-area associations, as well as meter-well associations. Mobile capabilities will be enabled in the near future for field workers to collect data and synchronize them to the spatial database. The entire solution is built on a highly scalable cloud

Imaging of underground karst water channels using an improved multichannel transient Rayleigh wave detecting method.

Science.gov (United States)

Zheng, Xuhui; Liu, Lei; Sun, Jinzhong; Li, Gao; Zhou, Fubiao; Xu, Jiemin

2018-01-01

Geological and hydrogeological conditions in karst areas are complicated from the viewpoint of engineering. The construction of underground structures in these areas is often disturbed by the gushing of karst water, which may delay the construction schedule, result in economic losses, and even cause heavy casualties. In this paper, an innovative method of multichannel transient Rayleigh wave detecting is proposed by introducing the concept of arrival time difference phase between channels (TDP). Overcoming the restriction of the space-sampling law, the proposed method can extract the phase velocities of different frequency components from only two channels of transient Rayleigh wave recorded on two adjacent detecting points. This feature greatly improves the work efficiency and lateral resolution of transient Rayleigh wave detecting. The improved multichannel transient Rayleigh wave detecting method is applied to the detection of karst caves and fractures in rock mass of the foundation pit of Yan'an Road Station of Guiyang Metro. The imaging of the detecting results clearly reveals the distribution of karst water inflow channels, which provided significant guidance for water plugging and enabled good control over karst water gushing in the foundation pit.

The atmospheric Cherenkov technique in searches for exploding primordial black holes

International Nuclear Information System (INIS)

Danaher, S.; Fegan, D.J.; Porter, N.A.; Weekes, T.C.

1981-01-01

The Cherenkov technique has been used with a number of detectors, ranging from 1.5 m 2 mirrors to the Central Receiver Test Facility of 8400 m 2 . Limits have been set to the flux of primordial black holes for various models of the evaporation process. (author)

Simple method of determining induced 32P activity following burning of sulfur tablets by measuring Cherenkov radiation

International Nuclear Information System (INIS)

Kubicek, I.

1986-01-01

A method is described allowing the detemination of induced beta activity of phosphorus-32 using Cherenkov radiation, following the burning of sulfur tablets in the measuring vesels. A mixture of phosphoric acid and sodium phosphate solutions was used as the medium for the production of Cherenkov radiation. The losses of activity during sulfur tablet burning, the detection efficiency and the minimum detectable activity for which the minimum determinable dose was estimated, were determined. The results obtained by measurement with Cherenkov radiation are compared with other techniques of phosphorus-32 detection. The method was tested at VUPL Bratislava on detectors irradited using a 252 Cf fast neutron source. From Caswell's data, the fluence-to-kerma conversin factor was determined for a neutron spectrum calculated by the Monte Carlo method. Tissue kerma was estimated from the neutron fluence corresponding to the appropriate values of saturated activity per 1 sulfur-32 nucleus. (author)

Development of new photon detection device for Cherenkov and fluorescence radiation

Directory of Open Access Journals (Sweden)

Tinti A.

2013-06-01

Full Text Available Recent progress on the development of a new solid state detector allowed the use of finely pixelled photocathodes obtained from silicon semiconductors. SiPM detectors seem to be an ideal tool for the detection of Cherenkov and fluorescence light in spite of their not yet resolved criticism for operating temperature and intrinsic noise. The main disadvantage of SiPM in this case is the poor sensitivity in the wavelength range 300-400 nm, where the Cherenkov light and fluorescence radiation are generated. We report on the possibility to realize a new kind of pixelled photodetector based on the use of silicon substrate with carbon nanotube compounds, more sensitive to the near UV radiation. Also if at the very beginning, the development of such detector appears very promising and useful for astroparticle physics, both in the ground based arrays and in the space experiments. The detectors are ready to be operated in conditions of measurements without signal amplification.

Prototype of a production system for Cherenkov Telescope Array with DIRAC

CERN Document Server

Arrabito, L; Haupt, A; Graciani Diaz, R; Stagni, F; Tsaregorodtsev, A

2015-01-01

The Cherenkov Telescope Array (CTA) — an array of many tens of Imaging Atmospheric Cherenkov Telescopes deployed on an unprecedented scale — is the next generation instrument in the field of very high energy gamma-ray astronomy. CTA will operate as an open observatory providing data products to the scientific community. An average data stream of about 10 GB/s for about 1000 hours of observation per year, thus producing several PB/year, is expected. Large CPU time is required for data-processing as well for massive Monte Carlo simulations needed for detector calibration purposes. The current CTA computing model is based on a distributed infrastructure for the archive and the data off-line processing. In order to manage the off-line data-processing in a distributed environment, CTA has evaluated the DIRAC (Distributed Infrastructure with Remote Agent Control) system, which is a general framework for the management of tasks over distributed heterogeneous computing environments. In particular, a production sy...

Construction experiences from underground works at Forsmark. Compilation Report

Energy Technology Data Exchange (ETDEWEB)

Carlsson, Anders [Vattenfall Power Consultant AB, Stockholm (Sweden); Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

2007-02-15

The main objective with this report, the Construction Experience Compilation Report (CECR), is to compile experiences from the underground works carried out at Forsmark, primarily construction experiences from the tunnelling of the two cooling water tunnels of the Forsmark nuclear power units 1, 2 and 3, and from the underground excavations of the undersea repository for low and intermediate reactor waste, SFR. In addition, a brief account is given of the operational experience of the SFR on primarily rock support solutions. The authors of this report have separately participated throughout the entire construction periods of the Forsmark units and the SFR in the capacity of engineering geologists performing geotechnical mapping of the underground excavations and acted as advisors on tunnel support; Anders Carlsson participated in the construction works of the cooling water tunnels and the open cut excavations for Forsmark 1, 2 and 3 (geotechnical mapping) and the Forsmark 3 tunnel (advise on tunnel support). Rolf Christiansson participated in the underground works for the SFR (geotechnical mapping, principal investigator for various measurements and advise on tunnel support and grouting). The report is to a great extent based on earlier published material as presented in the list of references. But it stands to reason that, during the course of the work with this report, unpublished notes, diaries, drawings, photos and personal recollections of the two authors have been utilised in order to obtain such a complete compilation of the construction experiences as possible.

Construction experiences from underground works at Forsmark. Compilation Report

International Nuclear Information System (INIS)

Carlsson, Anders; Christiansson, Rolf

2007-02-01

The main objective with this report, the Construction Experience Compilation Report (CECR), is to compile experiences from the underground works carried out at Forsmark, primarily construction experiences from the tunnelling of the two cooling water tunnels of the Forsmark nuclear power units 1, 2 and 3, and from the underground excavations of the undersea repository for low and intermediate reactor waste, SFR. In addition, a brief account is given of the operational experience of the SFR on primarily rock support solutions. The authors of this report have separately participated throughout the entire construction periods of the Forsmark units and the SFR in the capacity of engineering geologists performing geotechnical mapping of the underground excavations and acted as advisors on tunnel support; Anders Carlsson participated in the construction works of the cooling water tunnels and the open cut excavations for Forsmark 1, 2 and 3 (geotechnical mapping) and the Forsmark 3 tunnel (advise on tunnel support). Rolf Christiansson participated in the underground works for the SFR (geotechnical mapping, principal investigator for various measurements and advise on tunnel support and grouting). The report is to a great extent based on earlier published material as presented in the list of references. But it stands to reason that, during the course of the work with this report, unpublished notes, diaries, drawings, photos and personal recollections of the two authors have been utilised in order to obtain such a complete compilation of the construction experiences as possible

Urban underground infrastructure mapping and assessment

Science.gov (United States)

Huston, Dryver; Xia, Tian; Zhang, Yu; Fan, Taian; Orfeo, Dan; Razinger, Jonathan

2017-04-01

This paper outlines and discusses a few associated details of a smart cities approach to the mapping and condition assessment of urban underground infrastructure. Underground utilities are critical infrastructure for all modern cities. They carry drinking water, storm water, sewage, natural gas, electric power, telecommunications, steam, etc. In most cities, the underground infrastructure reflects the growth and history of the city. Many components are aging, in unknown locations with congested configurations, and in unknown condition. The technique uses sensing and information technology to determine the state of infrastructure and provide it in an appropriate, timely and secure format for managers, planners and users. The sensors include ground penetrating radar and buried sensors for persistent sensing of localized conditions. Signal processing and pattern recognition techniques convert the data in information-laden databases for use in analytics, graphical presentations, metering and planning. The presented data are from construction of the St. Paul St. CCTA Bus Station Project in Burlington, VT; utility replacement sites in Winooski, VT; and laboratory tests of smart phone position registration and magnetic signaling. The soil conditions encountered are favorable for GPR sensing and make it possible to locate buried pipes and soil layers. The present state of the art is that the data collection and processing procedures are manual and somewhat tedious, but that solutions for automating these procedures appear to be viable. Magnetic signaling with moving permanent magnets has the potential for sending lowfrequency telemetry signals through soils that are largely impenetrable by other electromagnetic waves.

First observation of Cherenkov ring images using hybrid photon detectors

International Nuclear Information System (INIS)

Albrecht, E.; Wilkinson, G.; Bibby, J.H.; Giles, R.; Harnew, N.; Smale, N.; Brook, N.H.; Halley, A.W.; O'Shea, V.; French, M.; Gibson, V.; Wotton, S.A.; Schomaker, R.

1998-01-01

A ring-imaging Cherenkov detector, equipped with hybrid photon detectors, has been operated in a charged-particle beam. Focussed ring images from various particle types were detected using silica aerogel, air and C 4 F 10 gas radiators. The detector, a prototype for the CERN LHC-B experiment, is described and first observations are reported. (orig.)

First observation of Cherenkov ring images using hybrid photon detectors

Energy Technology Data Exchange (ETDEWEB)

Albrecht, E.; Wilkinson, G. [European Organization for Nuclear Research, Geneva (Switzerland). Div. Particle Physics Experiments; Barber, G.; Duane, A.; John, M.; Miller, D.G.; Websdale, D. [Imperial College of Science Technology and Medicine, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom); Bibby, J.H.; Giles, R.; Harnew, N.; Smale, N. [University of Oxford, Department of Nuclear Physics, Keble Road, Oxford OX1 3RH (United Kingdom); Brook, N.H.; Halley, A.W.; O`Shea, V. [University of Glasgow, Department of Physics, Glasgow G12 8QQ (United Kingdom); French, M. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Gibson, V.; Wotton, S.A. [University of Cambridge, Cavendish Laboratory, Madingley Road, Cambridge CB3 0HE (United Kingdom); Schomaker, R. [Delft Electronic Products BV, 9300 AB Roden (Netherlands)

1998-07-11

A ring-imaging Cherenkov detector, equipped with hybrid photon detectors, has been operated in a charged-particle beam. Focussed ring images from various particle types were detected using silica aerogel, air and C{sub 4}F{sub 10} gas radiators. The detector, a prototype for the CERN LHC-B experiment, is described and first observations are reported. (orig.)

An algorithm for leak point detection of underground pipelines

International Nuclear Information System (INIS)

Lee, Young Sup; Yoon, Dong Jin

2004-01-01

Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband noise from a leak location and can be propagated to both directions of water pipes. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than 300 m.

Wireless Underground Sensor Networks: Channel Modeling and Operation Analysis in the Terahertz Band

Directory of Open Access Journals (Sweden)

Mustafa Alper Akkaş

2015-01-01

Full Text Available Wireless underground sensor networks (WUSNs are networks of sensor nodes operating below the ground surface, which are envisioned to provide real-time monitoring capabilities in the complex underground environments consisting of soil, water, oil, and other components. In this paper, we investigate the possibilities and limitations of using WUSNs for increasing the efficiency of oil recovery processes. To realize this, millimeter scale sensor nodes with antennas at the same scale should be deployed in the confined oil reservoir fractures. This necessitates the sensor nodes to be operating in the terahertz (THz range and the main challenge is establishing reliable underground communication despite the hostile environment which does not allow the direct use of most existing wireless solutions. The major problems are extremely high path loss, small communication range, and high dynamics of the electromagnetic (EM waves when penetrating through soil, sand, and water and through the very specific crude oil medium. The objective of the paper is to address these issues in order to propose a novel communication channel model considering the propagation properties of terahertz EM waves in the complex underground environment of the oil reservoirs and to investigate the feasible transmission distances between nodes for different water-crude-oil-soil-CO2 compositions.

Experimental and numerical investigations of a Cherenkov plasma maser

International Nuclear Information System (INIS)

Huet, D.; Pompier, F.; Vezinet, R.; Courtois, L.; Cubaynes, F.; Lalle, B.; Laporte, P.

2005-01-01

We are investigating the performances of a new tunable and low frequency (2-6 GHz band) Cherenkov plasma master driven by a 600 kV, 100 ns Tesla generator. We present experimental results in terms of energy and spectrum and their comparison with 2D computer simulations results versus voltage, plasma density and B field levels. The accelerator is presented in the first part of the paper [ru

Development of the fast and efficient gamma detector using Cherenkov light for TOF-PET

Science.gov (United States)

Canot, C.; Alokhina, M.; Abbon, P.; Bard, J. P.; Tauzin, G.; Yvon, D.; Sharyy, V.

2017-12-01

In this paper we present two configurations of innovative gamma detectors using Cherenkov light for time-of-flight—Positron Emission Tomography (PET). The first uses heavy crystals as a Cherenkov radiator to develop a demonstrator for a whole body PET scanner with high detection efficiency. We demonstrated a 30% detection efficiency and a 180 ps (FWHM) time resolution, mainly limited by the time transit spread of the photomultiplier. The second configuration uses an innovative liquid, the TriMethyl Bismuth, to develop a high precision brain-scanning PET device with time-of-flight capability. According to Geant4 simulation, we expect to reach a precision of 150 ps (FWHM) and an efficiency of about 25%.

Refilling material for underground disposal of radioactive waste

International Nuclear Information System (INIS)

Yajima, Tatsuya; Kato, Hiroyasu.

1995-01-01

Generally, the underground circumstance where radioactive wastes are to be processed is in high pH and highly ionized state due to ingredients leached out of cement of a concrete pit and solidifying products. A refilling material for underground disposal are demanded to adsorb radioactive nuclides such as 137 Cs even in such a state. As the refilling material, a mixture of bentonite and sintered vermiculite, preferably, comprising 10 to 40wt% of vermiculite is used. The refilling material has a high water hold out barrier performance of bentonite and a high radioactive nuclide adsorbing performance of vermiculite. In a state of highly ionized state when the adsorbing performance of bentonite is reduced, the nuclide-absorbing performance is improved by vermiculite and since the content of the vermiculite is not more than 40wt%, the water hold out barrier performance of the bentonite is not deteriorated. (N.H.)

Ultra-high energy cosmic rays. Results and status of the Pierre Auger Observatory

Energy Technology Data Exchange (ETDEWEB)

Peters, Christine [III. Physikalisches Institut A, RWTH Aachen University (Germany); Collaboration: Pierre-Auger-Collaboration

2016-07-01

The Pierre Auger Observatory is the world's largest experiment detecting extensive air showers initiated by cosmic rays at the highest energies. An area of 3000 km{sup 2} is instrumented by 1660 water Cherenkov detector stations, and 27 fluorescence telescopes overlook the atmosphere above the surface detector array. A hybrid detection principle is achieved by utilizing information of both detectors. A major upgrade of the experiment (AugerPrime) has been decided adding a third detector type, scintillator detector stations located on the water Cherenkov tanks. Thereby, the composition sensitivity of the Pierre Auger Observatory is extended by an improved determination of the muonic shower component. Additionally, underground muon detectors (AMIGA) are deployed. The experiment has been further extended by antennas measuring the emission of radio signals from air showers (AERA). An overview about recent results and the current status of the experiment are given in this talk. Highlights are updated results, e.g. on the energy spectrum, chemical composition or proton-air cross section.

Cherenkov-like emission of Z bosons

Science.gov (United States)

Colladay, D.; Noordmans, J. P.; Potting, R.

2017-07-01

We study CPT and Lorentz violation in the electroweak gauge sector of the Standard Model in the context of the Standard-Model Extension (SME). In particular, we show that any non-zero value of a certain relevant Lorentz violation parameter that is thus far unbounded by experiment would imply that for sufficiently large energies one of the helicity modes of the Z boson should propagate with spacelike four-momentum and become stable against decay in vacuum. In this scenario, Cherenkov-like radiation of Z bosons by ultra-high-energy cosmic-ray protons becomes possible. We deduce a bound on the Lorentz violation parameter from the observational data on ultra-high energy cosmic rays.

Inferences on mass composition and tests of hadronic interactions from 0.3 to 100 EeV using the water-Cherenkov detectors of the Pierre Auger Observatory

NARCIS (Netherlands)

Aab, A.; Abreu, P.; Aglietta, M.; Al Samarai, I.; Albuquerque, I.F.M.; Allekotte, I.; Almela, M.; Zuccarello, F.; van den Berg, Adriaan; Scholten, Olaf

2017-01-01

We present a new method for probing the hadronic interaction models atultrahigh energy and extracting details about mass composition. This isdone using the time profiles of the signals recorded with thewater-Cherenkov detectors of the Pierre Auger Observatory. The profilesarise from a mix of the

Determining the primary cosmic ray energy from the total flux of Cherenkov light measured at the Yakutsk EAS array

International Nuclear Information System (INIS)

Ivanov, A. A.; Knurenko, S. P.; Sleptsov, I. E.

2007-01-01

We present a method for determining the energy of the primary particle that generates an extensive air shower (EAS) of comic rays based on measuring the total flux of Cherenkov light from the shower. Applying this method to Cherenkov light measurements at the Yakutsk EAS array has allowed us to construct the cosmic ray energy spectrum in the range 10 15 - 3 x 10 19 eV

Cherenkov Ring Imaging Detector front-end electronics

International Nuclear Information System (INIS)

Antilogus, P.; Aston, D.; Bienz, T.; Bird, F.; Dasu, S.; Dunwoodie, W.; Hallewell, G.; Kawahara, H.; Kwon, Y.; Leith, D.; Marshall, D.; Muller, D.; Nagamine, T.; Oxoby, G.; Ratcliff, B.; Rensing, P.; Schultz, D.; Shapiro, S.; Simopoulos, C.; Solodov, E.; Suekane, F.; Toge, N.; Va'Vra, J.; Williams, S.; Wilson, R.J.; Whitaker, J.S.; Bean, A.; Caldwell, D.; Duboscq, J.; Huber, J.; Lu, A.; Mathys, L.; McHugh, S.; Morrison, R.; Witherell, M.; Yellin, S.; Coyle, P.; Coyne, D.; Spencer, E.; d'Oliveira, A.; Johnson, R.A.; Martinez, J.; Nussbaum, M.; Santha, A.K.S.; Shoup, A.; Stockdale, I.; Jacques, P.; Plano, R.; Stamer, P.; Abe, K.; Hasegawa, K.; Yuta, H.

1990-10-01

The SLD Cherenkov Ring Imaging Detector use a proportional wire detector for which a single channel hybrid has been developed. It consists of a preamplifier, gain selectable amplifier, load driver amplifier, power switching, and precision calibrator. For this hybrid, a bipolar, semicustom integrated circuit has been designed which includes video operational amplifiers for two of the gain stages. This approach allows maximization of the detector volume, allows DC coupling, and enables gain selection. System tests show good noise performance, calibration precision, system linearity, and signal shape uniformity over the full dynamic range. 10 refs., 8 figs

Cherenkov radiation conversion and collection considerations for a gamma bang time/reaction history diagnostic for the NIF.

Science.gov (United States)

Herrmann, Hans W; Mack, Joseph M; Young, Carlton S; Malone, Robert M; Stoeffl, Wolfgang; Horsfield, Colin J

2008-10-01

Bang time and reaction history measurements are fundamental components of diagnosing inertial confinement fusion (ICF) implosions and will be essential contributors to diagnosing attempts at ignition on the National Ignition Facility (NIF). Fusion gammas provide a direct measure of fusion interaction rate without being compromised by Doppler spreading. Gamma-based gas Cherenkov detectors that convert fusion gamma rays to optical Cherenkov photons for collection by fast recording systems have been developed and fielded at Omega. These systems have established their usefulness in illuminating ICF physics in several experimental campaigns. Bang time precision better than 25 ps has been demonstrated, well below the 50 ps accuracy requirement defined by the NIF system design requirements. A comprehensive, validated numerical study of candidate systems is providing essential information needed to make a down selection based on optimization of sensitivity, bandwidth, dynamic range, cost, and NIF logistics. This paper presents basic design considerations arising from the two-step conversion process from gamma rays to relativistic electrons to UV/visible Cherenkov radiation.

Cherenkov radiation conversion and collection considerations for a gamma bang time/reaction history diagnostic for the NIF

International Nuclear Information System (INIS)

Herrmann, Hans W.; Mack, Joseph M.; Young, Carlton S.; Malone, Robert M.; Stoeffl, Wolfgang; Horsfield, Colin J.

2008-01-01

Bang time and reaction history measurements are fundamental components of diagnosing inertial confinement fusion (ICF) implosions and will be essential contributors to diagnosing attempts at ignition on the National Ignition Facility (NIF). Fusion gammas provide a direct measure of fusion interaction rate without being compromised by Doppler spreading. Gamma-based gas Cherenkov detectors that convert fusion gamma rays to optical Cherenkov photons for collection by fast recording systems have been developed and fielded at Omega. These systems have established their usefulness in illuminating ICF physics in several experimental campaigns. Bang time precision better than 25 ps has been demonstrated, well below the 50 ps accuracy requirement defined by the NIF system design requirements. A comprehensive, validated numerical study of candidate systems is providing essential information needed to make a down selection based on optimization of sensitivity, bandwidth, dynamic range, cost, and NIF logistics. This paper presents basic design considerations arising from the two-step conversion process from γ rays to relativistic electrons to UV/visible Cherenkov radiation.

Development of the optical system for the SST-1M telescope of the Cherenkov Telescope Array observatory

CERN Document Server

Ostrowski, Michael; Błocki, J.; Bogacz, L.; Bulik, T.; Cadoux, F.; Christov, A.; Curyło, M.; della Volpe, D.; Dyrda, M.; Favre, Y.; Frankowski, A.; Grudnik, Ł.; Grudzińska, M.; Heller, M.; Idźkowski, B.; Jamrozy, M.; Janiak, M.; Kasperek, J.; Lalik, K.; Lyard, E.; Mach, E.; Mandat, D.; Marszałek, A.; Michałowski, J.; Moderski, R.; Montaruli, T.; Neronov, A.; Niemiec, J.; Paśko, P.; Pech, M.; Porcelli, A.; Prandini, E.; Pueschel, E.; Rajda, P.; Rameez, M.; Schioppa, E. jr; Schovanek, P.; Skowron, K.; Sliusar, V.; Sowiński, M.; Stawarz, Ł.; Stodulska, M.; Stodulski, M.; Toscano, S.; Troyano Pujadas, I.; Walter, R.; Wiȩcek, M.; Zagdański, A.; Ziȩtara, K.; Żychowski, P.; Barciński, T.; Karczewski, M.; Kukliński, J. Nicolau; Płatos, Ł.; Rataj, M.; Wawer, P.; Wawrzaszek, R.

2016-01-01

The prototype of a Davies-Cotton small size telescope (SST-1M) has been designed and developed by a consortium of Polish and Swiss institutions and proposed for the Cherenkov Telescope Array (CTA) observatory. The main purpose of the optical system is to focus the Cherenkov light emitted by extensive air showers in the atmosphere onto the focal plane detectors. The main component of the system is a dish consisting of 18 hexagonal mirrors with a total effective collection area of 6.47 m2 (including the shadowing and estimated mirror reflectivity). Such a solution was chosen taking into account the analysis of the Cherenkov light propagation and based on optical simulations. The proper curvature and stability of the dish is ensured by the mirror alignment system and the isostatic interface to the telescope structure. Here we present the design of the optical subsystem together with the performance measurements of its components.

Treating mine water

Energy Technology Data Exchange (ETDEWEB)

Matlak, E S; Kochegarova, L V; Zaslavskaya, I Yu

1980-10-01

Taking into account the negative influence of mine waters with suspended matter on the natural environment on the surface, the maximum treatment of mine water underground, is proposed. It is noted that full treatment of mine water, using conventional filtration methods, would be rather expensive, but a limited treatment of mine water is possible. Such treated mine water can be used in dust suppression and fire fighting systems. Mine water treated underground should be free of any odor, with pH level ranging from 6 to 9.5, with suspended matter content not exceeding 50 mg/l and coli-titre not less than 300 cm$SUP$3. It is suggested that water treatment to produce water characterized by these parameters is possible and economical. Recommendations on construction of underground sedimentation tanks and channels, and a hydraulic system of cleaning sedimentation tanks are proposed. The settling would be stored underground in abandoned workings. (2 refs.) (In Russian)

The image camera of the 17 m diameter air Cherenkov telescope MAGIC

CERN Document Server

Ostankov, A P

2001-01-01

The image camera of the 17 m diameter MAGIC telescope, an air Cherenkov telescope currently under construction to be installed at the Canary island La Palma, is described. The main goal of the experiment is to cover the unexplored energy window from approx 10 to approx 300 GeV in gamma-ray astrophysics. In its first phase with a classical PMT camera the MAGIC telescope is expected to reach an energy threshold of approx 30 GeV. The operational conditions, the special characteristics of the developed PMTs and their use with light concentrators, the fast signal transfer scheme using analog optical links, the trigger and DAQ organization as well as image reconstruction strategy are described. The different paths being explored towards future camera improvements, in particular the constraints in using silicon avalanche photodiodes and GaAsP hybrid photodetectors in air Cherenkov telescopes are discussed.

Design study of the underground facilities, the Mizunami Underground Research Laboratory

International Nuclear Information System (INIS)

Ishizuka, Mineo; Noda, Masaru; Shiogama, Yukihiro; Adachi, Tetsuya

1999-02-01

Geoscientific research on the deep geological environment has been performed by Japan Nuclear Cycle Development Institute (JNC). This research is supported by the 'Long-Term Program for Research, Development and Utilization of Nuclear Energy'. The Mizunami Underground Research Laboratory (MIU) is planned to be constructed at the Shobasama-bora site belonging to JNC. A wide range of geoscientific research and development activities which have been previously performed in and around the Tono mine is planned to be expanded in the laboratory. The MIU consisted of surface and underground facilities excavated to a depth of about 1,000 meters. In this design study, the overall layout and basic design of the underground facility and the composition of the overall research program, includes the construction of the underground facility are studied. Based on the concept of the underground facility which have been developed in 1998, the research activities which will be performed in the MIU are selected and the overall research program is revised in this year. The basic construction method and the construction equipment are also estimated. (author)

Design study of underground facility of the Mizunami Underground Research Laboratory

International Nuclear Information System (INIS)

Ishizuka, Mineo; Noda, Masaru; Shiogama, Yukihiro; Adachi, Tetsuya

1999-02-01

Geoscientific research on deep geological environment has been performed by Japan Nuclear Cycle Development Institute (JNC). This research is supported by the 'Long-Term Program for Research, Development and Utilization of Nuclear Energy'. The Mizunami Underground Research Laboratory (MIU) is planned to be constructed at Shobasama-bora site belonging to JNC. A wide range of geoscientific research and development activities which have been previously performed in and around the Tono mine is planned to be expanded in the laboratory. The MIU is consisted of surface and underground facilities down to the depth of about 1,000 meters. In this design study, the overall layout and basic design of the underground facility and the composition of the overall research program which includes the construction of the underground facility are studied. Based on the concept of the underground facility which have been developed last year, the research activities which will be performed in the MIU are selected and the overall research program is revised in this year. The basic construction method and the construction equipment are also estimated. (author)

Underground laboratories in Asia

International Nuclear Information System (INIS)

Lin, Shin Ted; Yue, Qian

2015-01-01

Deep underground laboratories in Asia have been making huge progress recently because underground sites provide unique opportunities to explore the rare-event phenomena for the study of dark matter searches, neutrino physics and nuclear astrophysics as well as the multi-disciplinary researches based on the low radioactive environments. The status and perspectives of Kamioda underground observatories in Japan, the existing Y2L and the planned CUP in Korea, India-based Neutrino Observatory (INO) in India and China JinPing Underground Laboratory (CJPL) in China will be surveyed

Underground laboratories in Asia

Energy Technology Data Exchange (ETDEWEB)

Lin, Shin Ted, E-mail: linst@mails.phys.sinica.edu.tw [College of Physical Science and Technology, Sichuan University, Chengdu 610064 China (China); Yue, Qian, E-mail: yueq@mail.tsinghua.edu.cn [Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics, Tsinghua University, Beijing 100084 China (China)

2015-08-17

Deep underground laboratories in Asia have been making huge progress recently because underground sites provide unique opportunities to explore the rare-event phenomena for the study of dark matter searches, neutrino physics and nuclear astrophysics as well as the multi-disciplinary researches based on the low radioactive environments. The status and perspectives of Kamioda underground observatories in Japan, the existing Y2L and the planned CUP in Korea, India-based Neutrino Observatory (INO) in India and China JinPing Underground Laboratory (CJPL) in China will be surveyed.

Towards a network of atmospheric Cherenkov detectors 7

International Nuclear Information System (INIS)

Robin, M.; Weekes, T.C.; Mori, M.; Mariotti, M.; Hofmann, W.; Aharonian, F.; Sinitsyna, V.; Smith, D.; Marleau, P.; Sinnis, G.; Volk, H.; Jager, O. de; Harding, A.; Coppi, P.; Dermer, C.; Goldwurm, A.; Paul, J.; Puhlhofer, G.; Bernardini, E.; Swordy, S.; Yoshikoshi, T.; Punch, M.

2005-01-01

This document gathers the papers and transparencies presented at the conference. The main part of the conference was organized into 6 sessions: 1) the review of present experiments (Veritas, Cangaroo-3, Magic, Hess-1, Shalon, Cactus, Cygnus-X-3...), 2) calibration and analysis techniques in VHE (very high energy) astrophysics, 3) multi-wavelength observations and phenomenology of sources, 4) the future of ground-based VHE astronomy, 5) developments in instrumentation for Cherenkov telescopes, and 6) the evolution of the field and its link with mainstream astrophysics

The forward ring imaging Cherenkov detector of DELPHI

International Nuclear Information System (INIS)

Adam, W.; Albrecht, E.; Ambec, I.; Augustinus, A.; Barnoux, C.; Bostjancic, B.; Botner, O.; Budziak, A.P.; Caloba, L.P.; Carecchio, P.; Cavalli, P.; Ceelie, L.; Cereseto, R.; Cerutti, G.; Dahl-Jensen, E.; Dam, P.; Damgaard, G.; Koning, N. de; De la Vega, A.S.; Dimitriou, N.; Dulinski, W.; Eek, L.O.; Ekeloef, T.; Erikson, J.; Florek, A.; Florek, B.; Fontanelli, F.; Fontenille, A.; Galuszka, K.; Garcia, J.; Gracco, V.; Hallgren, A.; Hao, W.; Henkes, T.; Isenhower, D.; Johansson, H.; Karvelas, E.; Kindblom, P.; Koene, B.; Korporaal, A.; Kostarakis, P.; Lenzen, G.; Lindqvist, L.E.; Lorenz, P.; Loukas, D.; Lund-Jensen, B.; Maltezos, A.; Markou, A.; Mattsson, L.; Medbo, J.; Michalowski, J.; Montano, F.; Nielsen, B.S.; Ostler, J.M.; Pakonski, K.; Perdikis, C.; Polok, G.; Robohm, A.; Sajot, G.; Sannino, M.; Saragas, E.; Schyns, E.; Squarcia, S.; Stavropoulos, G.; Stodulski, M.; Stopa, Z.; Thadome, J.; Theodosiou, G.E.; Traspedini, L.; Turala, M.; Ullaland, O.; Waerm, A.; Werner, J.; Xyroutsikos, S.; Zavrtanik, M.; Zevgolatakos, E.

1994-01-01

The Forward Ring Imaging Cherenkov detector of the DELPHI experiment at LEP provides hadron identification at polar angles 15 6 F 14 and a volume of gaseous C 4 F 10 , in combination provide coverage of momenta up to 40 GeV/c. A single array of photosensitive Time Projection Chambers registers the impact points of ultraviolet photons from both radiators. The design of the detector and of its readout system is described. First results obtained with a partly installed detector are reported. (orig.)

Towards a network of atmospheric Cherenkov detectors 7

Energy Technology Data Exchange (ETDEWEB)

Robin, M. [Ecole Polytechnique, 91 - Palaiseau (France); Weekes, T.C. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Mori, M. [Tokyo Univ., Institute for Cosmic Ray Research (Japan); Mariotti, M. [Padova Univ., INFN (Italy); Hofmann, W.; Aharonian, F. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Sinitsyna, V. [P.N. Lebedev Physical Institute, Moscow (Russian Federation); Smith, D. [Centre d' Etudes Nucleaires de Bordeaux Gradignan, 33 - Gradignan (France); Marleau, P. [California Univ., Davis, CA (United States); Sinnis, G. [Los Alamos National Lab., NM (United States); Volk, H. [Max-Planck-Institut fur Kernphysik (Germany); Jager, O. de [South Africa Univ., North-West (South Africa); Harding, A. [NASA Goddard Space Flight Center (United States); Coppi, P. [Yale Univ., New Haven, CT (United States); Dermer, C. [Naval Research Laboratory (United States); Goldwurm, A.; Paul, J. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee, 91- Gif sur Yvette (France); Puhlhofer, G. [Landessternwarte Heidelberg (Germany); Bernardini, E. [DESy-Zeuthen (Germany); Swordy, S. [Chicago Univ., IL (United States); Yoshikoshi, T. [Tokyo Univ., Tanashi (Japan). Inst. for Cosmic Ray Research; Teshima, M. [Max-Planck-Institute for Physics, Munich (Germany); Punch, M. [Astrophysique et Cosmologie (APC), College de France, 75 - Paris (France)

2005-07-01

This document gathers the papers and transparencies presented at the conference. The main part of the conference was organized into 6 sessions: 1) the review of present experiments (Veritas, Cangaroo-3, Magic, Hess-1, Shalon, Cactus, Cygnus-X-3...), 2) calibration and analysis techniques in VHE (very high energy) astrophysics, 3) multi-wavelength observations and phenomenology of sources, 4) the future of ground-based VHE astronomy, 5) developments in instrumentation for Cherenkov telescopes, and 6) the evolution of the field and its link with mainstream astrophysics.

Energy and electrode consumption analysis of electrocoagulation for the removal of arsenic from underground water

Energy Technology Data Exchange (ETDEWEB)

Martinez-Villafane, J.F., E-mail: mvjfer@gmail.com [CINVESTAV-IPN Unidad Saltillo, Carretera Saltillo-Monterrey Km 13.5, A.P. 663, 25900 Saltillo, Coahuila (Mexico); Montero-Ocampo, C.; Garcia-Lara, A.M. [CINVESTAV-IPN Unidad Saltillo, Carretera Saltillo-Monterrey Km 13.5, A.P. 663, 25900 Saltillo, Coahuila (Mexico)

2009-12-30

A systematic study of the effect of design and operation conditions of an electrochemical reactor on the treatment time for arsenic (As) electro-removal from underground water (GW) was carried out to analyse the energy and electrode consumption. The effects of four factors-current density, interelectrode distance, electrode area-volume ratio, and liquid motion driving mode-were evaluated. The response variables were the energy and the electrode consumption and the treatment time to reduce the GW residual As concentration to 10 {mu}g L{sup -1}, which is the maximum contaminant level (MCL) established by the World Health Organization (WHO) in drinking water. The results obtained in this study showed that the factor that had the greatest effect on most of the response variables was the liquid motion driving mode. The best residence time was 20 s, which favoured low energy consumption (58.78 Wh m{sup -3}) and low electrode material loss (9.59 g m{sup -3}).

Energy and electrode consumption analysis of electrocoagulation for the removal of arsenic from underground water

International Nuclear Information System (INIS)

Martinez-Villafane, J.F.; Montero-Ocampo, C.; Garcia-Lara, A.M.

2009-01-01

A systematic study of the effect of design and operation conditions of an electrochemical reactor on the treatment time for arsenic (As) electro-removal from underground water (GW) was carried out to analyse the energy and electrode consumption. The effects of four factors-current density, interelectrode distance, electrode area-volume ratio, and liquid motion driving mode-were evaluated. The response variables were the energy and the electrode consumption and the treatment time to reduce the GW residual As concentration to 10 μg L -1 , which is the maximum contaminant level (MCL) established by the World Health Organization (WHO) in drinking water. The results obtained in this study showed that the factor that had the greatest effect on most of the response variables was the liquid motion driving mode. The best residence time was 20 s, which favoured low energy consumption (58.78 Wh m -3 ) and low electrode material loss (9.59 g m -3 ).

Orpheus in the Underground

Directory of Open Access Journals (Sweden)

Puskás Dániel

2015-12-01

Full Text Available In my study I deal with descents to the underworld and hell in literature in the 20th century and in contemporary literature. I will focus on modem literary reinterpretations of the myth of Orpheus, starting with Rilke’s Orpheus. Eurydice. Hermes. In Seamus Heaney’s The Underground. in the Hungarian Istvan Baka’s Descending to the Underground of Moscow and in Czesław Miłosz’s Orpheus and Eurydice underworld appears as underground, similarly to the contemporary Hungarian János Térey’s play entitled Jeramiah. where underground will also be a metaphorical underworld which is populated with the ghosts of the famous deceased people of Debrecen, and finally, in Péter Kárpáti’s Everywoman the grave of the final scene of the medieval Everyman will be replaced with a contemporary underground station. I analyse how an underground station could be parallel with the underworld and I deal with the role of musicality and sounds in the literary works based on the myth of Orpheus.

Underground Layout Configuration

International Nuclear Information System (INIS)

A. Linden

2003-01-01

The purpose of this analysis was to develop an underground layout to support the license application (LA) design effort. In addition, the analysis will be used as the technical basis for the underground layout general arrangement drawings

Light collection and its fluctuation in Cherenkov and scintillation spectrometers

International Nuclear Information System (INIS)

Kitaev, D.F.; Samedov, V.V.; Stolyarova, E.L.

1982-01-01

The GAMMA program for calculating light collection in the Cherenkov and scintillation counters is described. Together with the shower modelling program the GAMNA program can be used for evaluating the output signal and energy resolution of shower spectrometers. Principle formulae and block diagram of the program are given. Results of test calculations performed on the example of scintillation counters of culindrical and rectangular shapes were considered. Modelling of the radiation polarization envisaged in the program permits to take account of the effect of selective discrimination of photoelectron amplifier photocathode. The program analyzes, for the present situation, calculation errors which permits to plan in advance the calculation with the given accuracy. The program permits to use additional subprograms together with it where it is possible to take account of other peculiarities of light collection, for example, the presence of outer reflectors and focusing elements of light collection systems, particle slowing down in the spectrometer radiator expressed in the change of angle of semiaperture of the Cherenkov radiation cone. It is concluded on the basis of analyzing results of test calculations that the choosen technique and algorithms of light collection coefficient calculation in spectrometer radiators are correct

40 CFR 280.220 - Ownership of an underground storage tank or underground storage tank system or facility or...

Science.gov (United States)

2010-07-01

... tank or underground storage tank system or facility or property on which an underground storage tank or underground storage tank system is located. 280.220 Section 280.220 Protection of Environment ENVIRONMENTAL... underground storage tank or underground storage tank system or facility or property on which an underground...

Estimation of underground river water availability based on rainfall in the Maros karst region, South Sulawesi

Science.gov (United States)

Arsyad, Muhammad; Ihsan, Nasrul; Tiwow, Vistarani Arini

2016-02-01

Maros karst region, covering an area of 43.750 hectares, has water resources that determine the life around it. Water resources in Maros karst are in the rock layers or river underground in the cave. The data used in this study are primary and secondary data. Primary data includes characteristics of the medium. Secondary data is rainfall data from BMKG, water discharge data from the PSDA, South Sulawesi province in 1990-2010, and the other characteristics data Maros karst, namely cave, flora and fauna of the Bantimurung Bulusaraung National Park. Data analysis was conducted using laboratory test for medium characteristics Maros karst, rainfall and water discharge were analyzed using Minitab Program 1.5 to determine their profile. The average rainfall above 200 mm per year occurs in the range of 1999 to 2005. The availability of the water discharge at over 50 m3/s was happened in 1993 and 1995. Prediction was done by modeling Autoregressive Integrated Moving Average (ARIMA), with the rainfall data shows that the average precipitation for four years (2011-2014) will sharply fluctuate. The prediction of water discharge in Maros karst region was done for the period from January to August in 2011, including the type of 0. In 2012, the addition of the water discharge started up in early 2014.

A mobile detector for measurements of the atmospheric muon flux in underground sites

Energy Technology Data Exchange (ETDEWEB)

Mitrica, Bogdan, E-mail: mitrica@nipne.ro [Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O.B. MG-6, 077125 Magurele (Romania); Margineanu, Romul; Stoica, Sabin; Petcu, Mirel; Brancus, Iliana [Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O.B. MG-6, 077125 Magurele (Romania); Jipa, Alexandru; Lazanu, Ionel; Sima, Octavian [Department of Physics, University of Bucharest, P.O.B. MG-11 (Romania); Haungs, Andreas; Rebel, Heinigerd [Institut fur Kernphysik, Karlsruhe Institute of Technology - Campus North, 76021 Karlsruhe (Germany); Petre, Marian; Toma, Gabriel; Saftoiu, Alexandra; Stanca, Denis; Apostu, Ana; Gomoiu, Claudia [Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O.B. MG-6, 077125 Magurele (Romania)

2011-10-21

Muons comprise an important contribution of the natural radiation dose in air (approx. 30 nSv/h of a total dose rate of 65-130 nSv/h), as well as in underground sites even when the flux and relative contribution are significantly reduced. The flux of muons observed underground can be used as an estimator for the depth in mwe (meter water equivalent) of the underground site. The water equivalent depth is important information to devise physics experiments feasible for a specific site. A mobile detector for performing measurements of the muon flux was developed in IFIN-HH, Bucharest. Consisting of two scintillator plates (approx. 0.9 m{sup 2}) which measure in coincidence, the detector is installed on a van which facilitates measurements at different locations at the surface or underground. The detector was used to determine muon fluxes at different sites in Romania. In particular, data were taken and the values of meter water equivalents were assessed for several locations at the salt mine in Slanic-Prahova, Romania. The measurements have been performed in two different galleries of the Slanic mine at different depths. In order to test the stability of the method, also measurements of the muon flux at the surface at different elevations were performed. The results were compared with predictions of Monte-Carlo simulations using the CORSIKA and MUSIC codes.

A mobile detector for measurements of the atmospheric muon flux in underground sites

International Nuclear Information System (INIS)

Mitrica, Bogdan; Margineanu, Romul; Stoica, Sabin; Petcu, Mirel; Brancus, Iliana; Jipa, Alexandru; Lazanu, Ionel; Sima, Octavian; Haungs, Andreas; Rebel, Heinigerd; Petre, Marian; Toma, Gabriel; Saftoiu, Alexandra; Stanca, Denis; Apostu, Ana; Gomoiu, Claudia

2011-01-01

Muons comprise an important contribution of the natural radiation dose in air (approx. 30 nSv/h of a total dose rate of 65-130 nSv/h), as well as in underground sites even when the flux and relative contribution are significantly reduced. The flux of muons observed underground can be used as an estimator for the depth in mwe (meter water equivalent) of the underground site. The water equivalent depth is important information to devise physics experiments feasible for a specific site. A mobile detector for performing measurements of the muon flux was developed in IFIN-HH, Bucharest. Consisting of two scintillator plates (approx. 0.9 m 2 ) which measure in coincidence, the detector is installed on a van which facilitates measurements at different locations at the surface or underground. The detector was used to determine muon fluxes at different sites in Romania. In particular, data were taken and the values of meter water equivalents were assessed for several locations at the salt mine in Slanic-Prahova, Romania. The measurements have been performed in two different galleries of the Slanic mine at different depths. In order to test the stability of the method, also measurements of the muon flux at the surface at different elevations were performed. The results were compared with predictions of Monte-Carlo simulations using the CORSIKA and MUSIC codes.

A wide dynamic range experiment to measure high energy γ-showers in air by detecting Cherenkov light in the middle ultraviolet

International Nuclear Information System (INIS)

Apollinari, G.; Bedeschi, F.; Belforte, S.; Bellettini, G.; Bertolucci, E.; Cervelli, F.; Chiarelli, G.; Dell'Orso, M.; Giannetti, P.; Menzione, A.; Ristori, L.; Scribano, A.; Sestini, P.; Stefanini, A.; Zetti, F.; Pisa Univ.

1988-01-01

An experiment to study high energy γ rays from localized cosmic sources is described. A number of Al mirrors reflects the Cherenkov light emitted by the showers into photosensitive gas chambers on the mirror focal plane. The use of gas chambers with large active areas allows a sensitivity superior to existing experiments to be reached. Pad readout gives the required angular accuracy. The chamber is sensitive to the middle ultraviolet Cherenkov light produced by the showers in the atmosphere. Since the ozone in the upper atmosphere absorbs the direct ultraviolet light from any outer source, the lower level atmosphere provides a large dark volume in which the Cherenkov radiation from the showers can be isolated. (orig.)

New technological methods for protecting underground waters from agricultural pollution

Science.gov (United States)

Mavlyanov, Gani

2015-04-01

The agricultural production on the irrigated grounds can not carry on without mineral fertilizers, pesticides and herbicides. Especially it is shown in Uzbekistan, in cultivation of cotton. There is an increase in mineralization, rigidity, quantity of heavy metals, phenols and other pollutions in the cotton fields. Thus there is an exhaustion of stocks of fresh underground waters. In the year 2003 we were offered to create the ecological board to prevent pollution to get up to a level of subsoil waters in the top 30 centimeter layer of the ground. We carried out an accumulation and pollution processing. This layer possesses a high adsorbing ability for heavy metals, mineral oil, mineral fertilizers remnants, defoliants and pesticides. In order to remediate a biological pollution treatment processing should be take into account. The idea is consisted in the following. The adsorption properties of coal is all well-known that the Angren coal washing factories in Tashkent area have collected more than 10 million tons of the coal dust to mix with clays. We have picked up association of anaerobic microorganisms which, using for development, destroys nutrients of coal waste pollutions to a harmless content for people. Coal waste inoculation also are scattered by these microorganisms on the field before plowing. Deep (up to 30 cm) plowing brings them on depth from 5 up to 30 cm. Is created by a plough a layer with necessary protective properties. The norm of entering depends on the structure of ground and the intensity of pollutions. Laboratory experiments have shown that 50% of pollutions can be treated by the ecological board and are processed up to safe limit.

A case study to detect the leakage of underground pressureless cement sewage water pipe using GPR, electrical, and chemical data.

Science.gov (United States)

Liu, Guanqun; Jia, Yonggang; Liu, Hongjun; Qiu, Hanxue; Qiu, Dongling; Shan, Hongxian

2002-03-01

The exploration and determination of leakage of underground pressureless nonmetallic pipes is difficult to deal with. A comprehensive method combining Ground Penetrating Rader (GPR), electric potential survey and geochemical survey is introduced in the leakage detection of an underground pressureless nonmetallic sewage pipe in this paper. Theoretically, in the influencing scope of a leakage spot, the obvious changes of the electromagnetic properties and the physical-chemical properties of the underground media will be reflected as anomalies in GPR and electrical survey plots. The advantages of GPR and electrical survey are fast and accurate in detection of anomaly scope. In-situ analysis of the geophysical surveys can guide the geochemical survey. Then water and soil sampling and analyzing can be the evidence for judging the anomaly is caused by pipe leakage or not. On the basis of previous tests and practical surveys, the GPR waveforms, electric potential curves, contour maps, and chemical survey results are all classified into three types according to the extent or indexes of anomalies in orderto find out the leakage spots. When three survey methods all show their anomalies as type I in an anomalous spot, this spot is suspected as the most possible leakage location. Otherwise, it will be down grade suspected point. The suspect leakage spots should be confirmed by referring the site conditions because some anomalies are caused other factors. The excavation afterward proved that the method for determining the suspected location by anomaly type is effective and economic. Comprehensive method of GRP, electric potential survey, and geochemical survey is one of the effective methods in the leakage detection of underground nonmetallic pressureless pipe with its advantages of being fast and accurate.

Features and performance of a large gas Cherenkov detector with threshold regulation

Energy Technology Data Exchange (ETDEWEB)

Alberdi, J.; Alvarez-Taviel, J.; Asenjo, L.; Colino, N.; Diez-Hedo. F.; Duran, I.; Gonzalez, J.; Hernandez, J.J.; Ladron de Guevara, P.; Marquina, M.A.

1988-01-15

We present here the development, main features and calibration procedures for a new type of gas Cherenkov detector, based upon the ability to control its threshold by regulating the temperature of the gas used as radiator. We also include the performance of this detector in particle identification.

Underground laboratories in Europe

International Nuclear Information System (INIS)

Coccia, E

2006-01-01

The only clear evidence today for physics beyond the standard model comes from underground experiments and the future activity of underground laboratories appears challenging and rich. I review here the existing underground research facilities in Europe. I present briefly the main characteristics, scientific activity and perspectives of these Laboratories and discuss the present coordination actions in the framework of the European Union

Radon in underground waters as a natural analogue to study the escape of CO2 in geological repositories.

Science.gov (United States)

Martín Sánchez, A; Ruano Sánchez, A B; de la Torre Pérez, J; Jurado Vargas, M

2015-11-01

Activity concentrations of dissolved (222)Rn and (226)Ra were measured in several underground aquifers, which are candidates for repositories or for the study of analogue natural escapes of CO2. The concentration of both radionuclides in water was determined using liquid scintillation counting. The values obtained for the (222)Rn concentrations varied from 0 to 150 Bq l(-1), while the levels of (226)Ra were in general very low. This indicates that (222)Rn is coming from the decay of the undissolved (226)Ra existing in the rocks and deep layers of the aquifers, being later transported by diffusion in water. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Aerogel Cherenkov Counters of the KEDR Detector

CERN Document Server

Ovtin, I V; Barnyakov, M Y; Bobrovnikov, V S; Buzykaev, A R; Danilyuk, A F; Katcin, A A; Kononov, S A; Kravchenko, E A; Kuyanov, I A; Onuchin, A P; Rodiakin, V A

2017-01-01

The particle identification system of the KEDR detector is based on aerogel threshold Cherenkov counters called ASHIPH counters. The system consists of 160 counters arranged in two layers. An event reconstruction program for the ASHIPH system was developed. The position of each counter relative to the tracking system was determined using cosmic muons and Bhabha events. The geometric efficiency of the ASHIPH system was verified with Bhabha events. The efficiency of relativistic particle detection was measured with cosmic muons. A π/K separation of 4δ in the momentum range 0.95 −1.45 GeV/c was confirmed. A simulation program for the ASHIPH counters has been developed.

Underground test area subproject waste management plan. Revision No. 1

International Nuclear Information System (INIS)

1996-08-01

The Nevada Test Site (NTS), located in southern Nevada, was the site of 928 underground nuclear tests conducted between 1951 and 1992. The tests were performed as part of the Atomic Energy Commission and U.S. Department of Energy (DOE) nuclear weapons testing program. The NTS is managed by the DOE Nevada Operations Office (DOE/NV). Of the 928 tests conducted below ground surface at the NTS, approximately 200 were detonated below the water table. As an unavoidable consequence of these testing activities, radionuclides have been introduced into the subsurface environment, impacting groundwater. In the few instances of groundwater sampling, radionuclides have been detected in the groundwater; however, only a very limited investigation of the underground test sites and associated shot cavities has been conducted to date. The Underground Test Area (UGTA) Subproject was established to fill this void and to characterize the risk posed to human health and the environment as a result of underground nuclear testing activities at the NTS. One of its primary objectives is to gather data to characterize the deep aquifer underlying the NTS

Influence of thermal fluctuations on Cherenkov radiation from fluxons in dissipative Josephson systems

DEFF Research Database (Denmark)

Antonov, A. A.; Pankratov, A. L.; Yulin, A. V.

2000-01-01

The nonlinear dynamics of fluxons in Josephson systems with dispersion and thermal fluctuations is analyzed using the "quasiparticle" approach to investigate the influence of noise on the Cherenkov radiation effect. Analytical expressions for the stationary amplitude of the emitted radiation...

Proposal of coherent Cherenkov radiation matched to circular plane wave for intense terahertz light source

International Nuclear Information System (INIS)

Sei, Norihiro; Sakai, Takeshi; Hayakawa, Ken; Tanaka, Toshinari; Hayakawa, Yasushi; Nakao, Keisuke; Nogami, Kyoko; Inagaki, Manabu

2015-01-01

Highlights: • We proposed a new intense terahertz-wave source based on coherent Cherenkov radiation (CCR). • A hollow conical dielectric is used to generate the CCR beam. • The wave front of the CCR beam can be matched to the basal plane. • The peak-power of the CCR beam is above 1 MW per micropulse with a short interval of 350 ps. - Abstract: We propose a high-peak-power terahertz-wave source based on an electron accelerator. By passing an electron beam through a hollow conical dielectric with apex facing the incident electron beam, the wave front of coherent Cherenkov radiation generated on the inner surface of the hollow conical dielectric matches the basal plane. Using the electron beam generated at the Laboratory for Electron Beam Research and Application at Nihon University, the calculated power of coherent Cherenkov radiation that matched the circular plane (CCR-MCP) was above 1 MW per micropulse with a short interval of 350 ps, for wavelengths ranging from 0.5 to 5 mm. The electron beam is not lost for generating the CCR-MCP beam by using the hollow conical dielectric. It is possible to combine the CCR-MCP beams with other light sources based on an accelerator

The development of simulation and atmospheric shower reconstruction tools for the study of future Cherenkov Imaging telescopes

International Nuclear Information System (INIS)

Sajjad, S.

2007-09-01

The future of ground based gamma-ray astronomy lies in large arrays of Imaging Atmospheric Cherenkov Telescopes with better capabilities: lower energy threshold, higher sensitivity, better resolution and background rejection. The design of IACT systems and the optimisation of their parameters requires an understanding of the atmospheric showers as well as dedicated tools for the simulation of telescope systems and the evaluation of their performance. The first part of this dissertation deals with atmospheric showers, the various properties of the Cherenkov light they emit and their simulation. The second part presents the tools we have developed for the simulation of imaging atmospheric Cherenkov telescopes and the characteristics of the shower images obtained by them. The third part of this thesis contains a presentation of the tools developed for the reconstruction of the source position in the sky, core position on the ground and energy of the gamma-rays as well as ideas for gamma-hadron separation. In the end, we use these tools to study two large arrays of telescopes at two altitudes and evaluate their performance for gamma-ray detection. (author)

Underground space planning in Helsinki

Directory of Open Access Journals (Sweden)

Ilkka Vähäaho

2014-10-01

Full Text Available This paper gives insight into the use of underground space in Helsinki, Finland. The city has an underground master plan (UMP for its whole municipal area, not only for certain parts of the city. Further, the decision-making history of the UMP is described step-by-step. Some examples of underground space use in other cities are also given. The focus of this paper is on the sustainability issues related to urban underground space use, including its contribution to an environmentally sustainable and aesthetically acceptable landscape, anticipated structural longevity and maintaining the opportunity for urban development by future generations. Underground planning enhances overall safety and economy efficiency. The need for underground space use in city areas has grown rapidly since the 21st century; at the same time, the necessity to control construction work has also increased. The UMP of Helsinki reserves designated space for public and private utilities in various underground areas of bedrock over the long term. The plan also provides the framework for managing and controlling the city's underground construction work and allows suitable locations to be allocated for underground facilities. Tampere, the third most populated city in Finland and the biggest inland city in the Nordic countries, is also a good example of a city that is taking steps to utilise underground resources. Oulu, the capital city of northern Finland, has also started to ‘go underground’. An example of the possibility to combine two cities by an 80-km subsea tunnel is also discussed. A new fixed link would generate huge potential for the capital areas of Finland and Estonia to become a real Helsinki-Tallinn twin city.

Design and construction of a Cherenkov imager for charge measurement of nuclear cosmic rays

International Nuclear Information System (INIS)

Bourrion, O; Bernard, C; Bondoux, D; Bouly, J L; Bouvier, J; Boyer, B; Brinet, M; Buenerd, M; Damieux, G; Derome, L; Eraud, L; Foglio, R; Fombaron, D; Grondin, D; Marton, M; Pelissier, A; Lee, M H; Lutz, L; Menchaca-Rocha, A; Perie, J N

2011-01-01

A proximity focusing Cherenkov imager called CHERCAM, has been built for the charge measurement of nuclear cosmic rays with the CREAM instrument. It consists of a silica aerogel radiator plane across from a detector plane equipped with 1,600 1'' diameter photomultipliers. The two planes are separated by a ring expansion gap. The Cherenkov light yield is proportional to the charge squared of the incident particle. The expected relative light collection accuracy is in the few percents range. It leads to an expected single element separation over the range of nuclear charge Z of main interest 1 ≤ Z∼<26. CHERCAM is designed to fly with the CREAM balloon experiment. The design of the instrument and the implemented technical solutions allowing its safe operation in high altitude conditions (radiations, low pressure, cold) are presented.

Underground openings production line 2012. Design, production and initial state of the underground openings

International Nuclear Information System (INIS)

2013-08-01

The Underground Openings Line Production Line report describes the design requirements, the design principles, the methods of construction and the target properties for the underground rooms required for the final repository. It is one of five Production Line reports, namely the: Underground Openings Line report, Canister report, Buffer report, Backfill report, Closure report. Together, these reports cover the lifespan of the underground phases of the final repository from the start of construction of the underground rooms to their closure. Posiva has developed reference methods for constructing the underground rooms. Tunnels will be constructed using the drill and blast technique, shafts will be constructed using raise boring and the deposition holes will be constructed by reverse down reaming. Underground openings will be made safe by reinforcement by using rock bolts, net or shotcrete, depending on which type of opening is being considered, and groundwater inflows will be limited by grouting. Posiva's requirements management system (VAHA) sets out the specifications for the enactment of the disposal concept at Olkiluoto under five Levels - 1 to 5, from the most generic to the most specific. In this report, the focus is on Level 4 and 5 requirements, which provide practical guidance for the construction of the underground openings. The design requirements are presented in Level 4 and the design specification in Level 5 In addition to the long-term safety-related requirements included in VAHA, there are additional requirements regarding the operation of underground openings, e.g. space requirements due to the equipment used and its maintenance, operational and fire safety. The current reference design for the disposal facility is presented based on the design requirements and design specifications. During the lifespan of the repository the reference design will be revised and updated according to the design principles as new information is available. Reference

Study of reaction between water and exhaust gases from diesel engines used in underground mining

Energy Technology Data Exchange (ETDEWEB)

Mazukhina, S.I.; Kalabin, G.V.; Romanov, V.S.

1988-05-01

A method of mathematical simulation, based on the principle of local equilibrium of the kinetic components, was proposed for formulating and solving problems related to the combustion of fuel and the treatment of exhaust gases from a diesel engine in underground workings. Results of a study of the effects of exhaust gas quantity and composition on the reaction between the gases and water are presented. It is shown that the kinetic model correlates well with the equilibrium model, adequately describes the process, and gives a reliable picture of the changes over a period of time. The proposed method can be used to study the gas emission with different fuel mixtures and liquid neutralizing agents with a view to reducing the toxicity of diesel-engine exhaust gases.

Hydrologic and water quality characteristics of a partially-flooded, abandoned underground coal mine

International Nuclear Information System (INIS)

Aljoe, W.W.

1994-01-01

The hydrologic and water quality characteristics of a partially flooded, abandoned underground coal mine near Latrobe, PA, were studied to support the development of techniques for in situ abatement of its acidic discharge. A quantitative understanding of the conditions affecting discharge flow was considered to be very important in this regard. Statistical analysis of hydrologic data collected at the site shows that the flow rate of the main discharge (a borehole that penetrates the mine workings just behind a set of portal seals) is a linear function of the height of the mine pool above the borehole outlet. Seepage through or around the portal seals is collected by a set of french drains whose discharge rate is largely independent of the mine pool elevation. This seepage was enhanced after a breakthrough that occurred during a period of unusually high pool levels. The mine pool recharge rate during winter is about 2.5 times greater than that of any other season; recharge rates during spring, summer, and fall are approximately equal. Mine pool and discharge water quality information, along with bromide tracer tests, suggest that the original main entries discharge primarily to the french drains, while the borehole carries the discharge from an unmonitored set of entries northwest of the mains. The water quality of the east french drain discharge may have been improved substantially after seepage through the alkaline materials used to construct the portal seals

Study on the leach mechanism of 90-19/U glass form in underground water of disposal site

International Nuclear Information System (INIS)

Sheng Jiawei; Luo Shanggeng; Tang Baolong

1996-01-01

The leach behavior of 90-19/U glass form in underground water (UW) of disposal site and in the deionized water (DIW) is studied. The total mass losses of glass form and the normalized element mass losses of B, Li and Si in UW are presented and compared to DIW. It is found that the ions in UW affect the leach behavior of 90-19/U glass. At the beginning of the reaction the reaction rate of the glass is smaller in UW than in DIW due to the low glass dissolution affinity in UW which is defined as (1-c/K). The rate determining step of leach reaction of 90-19/U glass in UW during the entire reaction period is the ion-exchange reaction. The apparent activation energy of glass reaction in UW is 51.6 kJ/mol

Regulatory approaches to hydrocarbon contamination from underground storage tanks

International Nuclear Information System (INIS)

Daugherty, S.J.

1991-01-01

Action or lack of action by the appropriate regulatory agency is often the most important factor in determining remedial action or closure requirements for hydrocarbon contaminated sites. This paper reports that the diversity of regulatory criteria is well known statewide and well documented nationally. In California, the diversity of approaches is due to: that very lack of a clear understanding of the true impact of hydrocarbon contamination: lack of state or federal standards for soil cleanup, and state water quality objectives that are not always achievable; vagueness in the underground storage tank law; and the number and diversity of agencies enforcing the underground storage tank regulations

Transfer mechanisms in cultivated soils of waste radionuclides from electronuclear power plants in the system river--irrigated soil--underground water level

Energy Technology Data Exchange (ETDEWEB)

Saas, A; Grauby, A

1974-12-31

From symposinm on environmentl behavior of radionuclides released in the nuclear industry; Aix-en-Provence, France (14 May 1973). The location of nuclear power plants by rivers whose waters are used for irrigation and industrial and domestic consumption necessities a profound study of the river-irrigated soil- ground water system. Mechanisms of radionuclide transport in cultivated soil are considered under three principal aspects: the effect of the quality of the river water, of the irrigation channels, and of the ground water level on the mobility of the radionuclides in the soil; the influence of the type of soil (the four types of soils considered are acid brown soil, calcic brown soil, chalky brown soil, and chalky alluvial soil); and the distribution of radionuclides in the soil (hydrosoluble forms can contminate the ground water level and these are the forms in which they are taken up by plants. A study was made on the following nuclides: /sup 22/Na, /sup 137/Cs, /sup 85/Sr, /Sup 54/Mn, /Sup 59/Fe, /Sup 60/ Co, /sup 65/Zn, /sup 124/Sb, /sup 141 in the cultivated soils permit the evaluation of the risks of contmination of the food chain and of the underground water. This study also showed new perspectives of the behavior of radionuclides as a function of their contmination of the organo-mineral wastes of industrial and domestic origin. This pollution interfers largely with the formation of stble complexes carried by the river to irrigated soils. The quality of the water determines the distribution of the radionuclides in the profile. The hydrosoluble complex persists in the soil and migrates toward the underground water level if they are not biodegradable. The stability of these forms as a function of the soil pH and of its physicochemical characteristics, as well as that of the radionuclides considered, permit the formulation of a new balance of the radionuclides in soils. The formulation of new proposals for the contml of nuclear sites is discussed. (tr-auth)

Gamma/hadron segregation for a ground based imaging atmospheric Cherenkov telescope using machine learning methods: Random Forest leads

International Nuclear Information System (INIS)

Sharma Mradul; Koul Maharaj Krishna; Mitra Abhas; Nayak Jitadeepa; Bose Smarajit

2014-01-01

A detailed case study of γ-hadron segregation for a ground based atmospheric Cherenkov telescope is presented. We have evaluated and compared various supervised machine learning methods such as the Random Forest method, Artificial Neural Network, Linear Discriminant method, Naive Bayes Classifiers, Support Vector Machines as well as the conventional dynamic supercut method by simulating triggering events with the Monte Carlo method and applied the results to a Cherenkov telescope. It is demonstrated that the Random Forest method is the most sensitive machine learning method for γ-hadron segregation. (research papers)

Note: Measurements of fast electrons in the TORE-SUPRA tokamak by means of modified Cherenkov-type diamond detector

Energy Technology Data Exchange (ETDEWEB)

Jakubowski, L.; Sadowski, M. J.; Zebrowski, J.; Rabinski, M.; Jakubowski, M. J.; Malinowski, K.; Mirowski, R. [National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock (Poland); Lotte, Ph.; Goniche, M.; Gunn, J.; Colledani, G.; Pascal, J.-Y.; Basiuk, V. [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France)

2013-01-15

The Note reports on experimental studies of ripple born fast electrons within the TORE-SUPRA facility, which were performed by means of a modified measuring head equipped with diamond detectors designed especially for recording the electron-induced Cherenkov radiation. There are presented signals produced by fast electrons in the TORE-SUPRA machine, which were recorded during two experimental campaigns performed in 2010. Shapes of these electron-induced signals are considerably different from those observed during the first measurements carried out by the prototype Cherenkov probe in 2008. An explanation of the observed differences is given.

Note: Measurements of fast electrons in the TORE-SUPRA tokamak by means of modified Cherenkov-type diamond detector

International Nuclear Information System (INIS)

Jakubowski, L.; Sadowski, M. J.; Zebrowski, J.; Rabinski, M.; Jakubowski, M. J.; Malinowski, K.; Mirowski, R.; Lotte, Ph.; Goniche, M.; Gunn, J.; Colledani, G.; Pascal, J.-Y.; Basiuk, V.

2013-01-01

The Note reports on experimental studies of ripple born fast electrons within the TORE-SUPRA facility, which were performed by means of a modified measuring head equipped with diamond detectors designed especially for recording the electron-induced Cherenkov radiation. There are presented signals produced by fast electrons in the TORE-SUPRA machine, which were recorded during two experimental campaigns performed in 2010. Shapes of these electron-induced signals are considerably different from those observed during the first measurements carried out by the prototype Cherenkov probe in 2008. An explanation of the observed differences is given.

Evaluation of natural radioactivity in superficial and underground drinking water, from the Caetite region, BA

International Nuclear Information System (INIS)

Silva, Luciana Sousa

2011-01-01

Brazil has the seventh greatest geological uranium reserve in the world with approximately 310 thousand tons. The Lagoa Real Uranium Province, in the region of Caetite and Lagoa Real, situated in South Center Bahia, is considered the most important monomineralic province in Brazil. Urban population who lives in the uranium district in the cities of Caetite, Lagoa Real and Livramento de Nossa Senhora uses drinking water originated from public supply. In the rural area, characterized by frequent draughts, residents receive water from digged and drilled wells and from small dams and reservoirs, as well, which are supplied by the rains. This work determined the levels of total alpha and beta radioactivity and the uranium concentrations in several kinds of water consumed by urban and rural population from the Lagoa Real Uranium Province. Total α and β activities were determined with a low-level gas flow proportional detector. The uranium concentrations were determined with an inductive coupled plasma-mass spectrometer (ICP-MS). The results obtained were confronted with the latest World Health Organization's recommendations from 2011, the ordinance number 2914 of December 12 2011 from the Health Ministry and CONAMA's resolutions. Natural radiation levels varied from 0,0041 ± 0,0004 Bq.L -1 to 0,80 ± 0,04 Bq.L -1 for total alpha activity and from 0,045 ± 0,003 to 3,00 ± 0,2 Bq.L -1 for total beta activity. Having the WHO and the HM as parameter, just two underground water samples, one located in the city of Lagoa Real and the other in the city of Caetite presented total alpha concentration above the value of 0,5 Bq.L -1 described in its recommendations, 0,80 ± 0,040 Bq.L -1 and 0,57 ± 0,03 Bq.L -1 respectively. For total beta three samples presented radioactivity levels above the 1 Bq.L -1 limit recommended by the WHO and established by the Health Ministry; 3,00 ± 0,2 Bq.L -1 ; 1,63 ± 0,13 Bq.L -1 and 1,19 ± 0,07 Bq.L -1 ., all of them situated in the Lagoa

Simulation studies of an air Cherenkov telescope, IceACT, for future IceCube surface extensions

Energy Technology Data Exchange (ETDEWEB)

Hansmann, Bengt; Auffenberg, Jan; Bekman, Ilja; Kemp, Julian; Roegen, Martin; Schaufel, Merlin; Stahlberg, Martin; Wiebusch, Christopher [III. Physikalisches Institut B, RWTH Aachen, Aachen (Germany); Bretz, Thomas; Hebbeker, Thomas; Middendorf, Lukas; Niggemann, Tim; Schumacher, Johannes [III. Physikalisches Institut A, RWTH Aachen, Aachen (Germany); Collaboration: IceCube-Collaboration

2015-07-01

IceACT is a compact air Cherenkov telescope using silicon photomultipliers. The Fresnel lens based design has been adopted from the fluorescence telescope FAMOUS. The goal of IceACT is the efficient detection of cosmic ray induced air showers above the IceCube Neutrino Observatory at the geographic South Pole. This allows to distinguish cosmic ray induced muons and neutrinos in the southern sky from astrophysical neutrinos in the deep ice detector. This leads to an increase in low-background astrophysical neutrinos of several dozen events per year for a detection threshold of several 100 TeV cosmic ray primary energy. To determine the actual telescope performance, dedicated CORSIKA air shower simulations incorporating the full Cherenkov light information are performed.

Microbial Life in an Underground Gas Storage Reservoir

Science.gov (United States)

Bombach, Petra; van Almsick, Tobias; Richnow, Hans H.; Zenner, Matthias; Krüger, Martin

2015-04-01

While underground gas storage is technically well established for decades, the presence and activity of microorganisms in underground gas reservoirs have still hardly been explored today. Microbial life in underground gas reservoirs is controlled by moderate to high temperatures, elevated pressures, the availability of essential inorganic nutrients, and the availability of appropriate chemical energy sources. Microbial activity may affect the geochemical conditions and the gas composition in an underground reservoir by selective removal of anorganic and organic components from the stored gas and the formation water as well as by generation of metabolic products. From an economic point of view, microbial activities can lead to a loss of stored gas accompanied by a pressure decline in the reservoir, damage of technical equipment by biocorrosion, clogging processes through precipitates and biomass accumulation, and reservoir souring due to a deterioration of the gas quality. We present here results from molecular and cultivation-based methods to characterize microbial communities inhabiting a porous rock gas storage reservoir located in Southern Germany. Four reservoir water samples were obtained from three different geological horizons characterized by an ambient reservoir temperature of about 45 °C and an ambient reservoir pressure of about 92 bar at the time of sampling. A complementary water sample was taken at a water production well completed in a respective horizon but located outside the gas storage reservoir. Microbial community analysis by Illumina Sequencing of bacterial and archaeal 16S rRNA genes indicated the presence of phylogenetically diverse microbial communities of high compositional heterogeneity. In three out of four samples originating from the reservoir, the majority of bacterial sequences affiliated with members of the genera Eubacterium, Acetobacterium and Sporobacterium within Clostridiales, known for their fermenting capabilities. In

Ground-based gamma-ray astronomy with Cherenkov telescopes

International Nuclear Information System (INIS)

Hinton, Jim

2009-01-01

Very high-energy (>100 GeV) γ-ray astronomy is emerging as an important discipline in both high-energy astrophysics and astro-particle physics. This field is currently dominated by imaging atmospheric-Cherenkov telescopes (IACTs) and arrays of these telescopes. Such arrays have achieved the best angular resolution and energy flux sensitivity in the γ-ray domain and are still far from the fundamental limits of the technique. Here, I will summarize some key aspects of this technique and go on to review the current status of the major instruments and to highlight selected recent results.

Development of a smart rock bolt for underground monitoring operations

CSIR Research Space (South Africa)

Moema, JS

2003-07-01

Full Text Available of magnetic methods in measuring the stress or microstructural transformation in an individual bolt in both laboratory and underground environment. The corrosion performance of the smart bolt alloy was evaluated in synthetic mine water and compared...

JAPAN: Super-Kamiokande

International Nuclear Information System (INIS)

Anon.

1994-01-01

Excavation for the Japanese Super- KAMIOKANDE 50,000-ton water Cherenkov imaging detector was completed at the end of June. The goals include a search for nucleon decay up to a lifetime of 10 33-34 years, high-statistics studies of solar and atmospheric neutrinos, and detection of any nearby supernova explosions. The project was approved in 1991, with the official 'groundbreaking' in December of that year about 1,000 m underground in the Kamioka mine in Gifu Prefecture, about 250 km west of Tokyo

Measuring Dirac CP-violating phase with intermediate energy beta beam facility

Science.gov (United States)

Bakhti, P.; Farzan, Y.

2014-02-01

Taking the established nonzero value of , we study the possibility of extracting the Dirac CP-violating phase by a beta beam facility with a boost factor . We compare the performance of different setups with different baselines, boost factors, and detector technologies. We find that an antineutrino beam from He decay with a baseline of km has a very promising CP-discovery potential using a 500 kton water Cherenkov detector. Fortunately this baseline corresponds to the distance between FermiLAB to Sanford underground research facility in South Dakota.

Cherenkov Video Imaging Allows for the First Visualization of Radiation Therapy in Real Time

International Nuclear Information System (INIS)

Jarvis, Lesley A.; Zhang, Rongxiao; Gladstone, David J.; Jiang, Shudong; Hitchcock, Whitney; Friedman, Oscar D.; Glaser, Adam K.; Jermyn, Michael; Pogue, Brian W.

2014-01-01

Purpose: To determine whether Cherenkov light imaging can visualize radiation therapy in real time during breast radiation therapy. Methods and Materials: An intensified charge-coupled device (CCD) camera was synchronized to the 3.25-μs radiation pulses of the clinical linear accelerator with the intensifier set × 100. Cherenkov images were acquired continuously (2.8 frames/s) during fractionated whole breast irradiation with each frame an accumulation of 100 radiation pulses (approximately 5 monitor units). Results: The first patient images ever created are used to illustrate that Cherenkov emission can be visualized as a video during conditions typical for breast radiation therapy, even with complex treatment plans, mixed energies, and modulated treatment fields. Images were generated correlating to the superficial dose received by the patient and potentially the location of the resulting skin reactions. Major blood vessels are visible in the image, providing the potential to use these as biological landmarks for improved geometric accuracy. The potential for this system to detect radiation therapy misadministrations, which can result from hardware malfunction or patient positioning setup errors during individual fractions, is shown. Conclusions: Cherenkoscopy is a unique method for visualizing surface dose resulting in real-time quality control. We propose that this system could detect radiation therapy errors in everyday clinical practice at a time when these errors can be corrected to result in improved safety and quality of radiation therapy

Evaluation of earthquake resistance design for underground structures of nuclear power plant, (1)

International Nuclear Information System (INIS)

Tohma, Junichi; Kokusho, Kenji; Iwatate, Takahiro; Ohtomo, Keizo

1986-01-01

As to earthquake resistant design of underground civil engineering structures related with emergency cooling water system of nuclear power plant, it is required these structures must maintain the function of great important their own facilities during earthquakes, especially for design earthquake motion. In this study, shaft pipline, pit and duct for cooling sea water facilities were chosen as typical underground structures, and the authors deal with the seismic design method for calculation of the principal sectional force in these structures generated by design earthquake motion. Especially, comparative investigations concerned with response displacement method versus dynamic analysis methods (lumped mass analysis and finite element analysis) are discussed. (author)

The aerogel Ring Imaging Cherenkov system at the Belle II spectrometer

Science.gov (United States)

Pestotnik, R.; Adachi, I.; Dolenec, R.; Hataya, K.; Iori, S.; Iwata, S.; Kakuno, H.; Kataura, R.; Kawai, H.; Kindo, H.; Kobayashi, T.; Korpar, S.; Križan, P.; Kumita, T.; Mrvar, M.; Nishida, S.; Ogawa, K.; Ogawa, S.; Šantelj, L.; Sumiyoshi, T.; Tabata, M.; Yonenaga, M.; Yusa, Y.

2017-12-01

In the forward end-cap of the Belle II spectrometer, a proximity focusing Ring Imaging Cherenkov counter with an aerogel radiator will be installed. The detector will occupy a limited space inside solenoid magnet with longitudinal field of 1.5 T. It will consist of a double layer aerogel radiator, an expansion volume and a photon detector. 420 Hamamatsu hybrid avalanche photo sensors with 144 channels each will be used to read out single Cherenkov photons with high efficiency. More than 60,000 analog signals will be digitized and processed in the front end electronics and send to the unified experiment data acquisition system. The detector components have been successfully produced and are now being installed in the spectrometer. Tested before on the bench, they are currently being installed in the mechanical frame. Part of the detector have been commissioned and connected to the acquisition system to register the cosmic ray particles. The first preliminary results are in accordance with previous expectations. We expect an excellent performance of the device which will allow at least a 4σ separation of pions from kaons in the experiment kinematic region from 0.5 GeV/c to 4 GeV/c.

Global Pursuits: The Underground Railroad

Science.gov (United States)

School Arts: The Art Education Magazine for Teachers, 2004

2004-01-01

This brief article describes Charles T. Webber's oil on canvas painting, "The Underground Railroad, 1893." The subject of this painting is the Underground Railroad, which today has become an American legend. The Underground Railroad was not a systematic means of transportation, but rather a secretive process that allowed fugitive slaves…

Design and construction of a Cherenkov imager for charge measurement of nuclear cosmic rays

Energy Technology Data Exchange (ETDEWEB)

Bourrion, O; Bernard, C; Bondoux, D; Bouly, J L; Bouvier, J; Boyer, B; Brinet, M; Buenerd, M; Damieux, G; Derome, L; Eraud, L; Foglio, R; Fombaron, D; Grondin, D; Marton, M; Pelissier, A [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, 53, rue des Martyrs, Grenoble (France); Lee, M H; Lutz, L [University of Maryland, College Park MD 20742 (United States); Menchaca-Rocha, A [Instituto de Fisica, UNAM, A.P. 20-364, 01000 Mexico DF (Mexico); Perie, J N, E-mail: olivier.bourrion@lpsc.in2p3.fr [Universite de Toulouse, INSA, UPS, Mines Albi, ISAE, ICA (Institut Clement Ader), 133, avenue de Rangueil, F-31077 Toulouse (France)

2011-06-15

A proximity focusing Cherenkov imager called CHERCAM, has been built for the charge measurement of nuclear cosmic rays with the CREAM instrument. It consists of a silica aerogel radiator plane across from a detector plane equipped with 1,600 1'' diameter photomultipliers. The two planes are separated by a ring expansion gap. The Cherenkov light yield is proportional to the charge squared of the incident particle. The expected relative light collection accuracy is in the few percents range. It leads to an expected single element separation over the range of nuclear charge Z of main interest 1 {<=} Z{approx}<26. CHERCAM is designed to fly with the CREAM balloon experiment. The design of the instrument and the implemented technical solutions allowing its safe operation in high altitude conditions (radiations, low pressure, cold) are presented.

Cherenkov radiation by an electron bunch that moves in a vacuum above a left-handed material

International Nuclear Information System (INIS)

Averkov, Yu.O.; Yakovenko, V.M.

2005-01-01

Cherenkov radiation by a nonrelativistic electron bunch that moves above an interface of a vacuum-left-handed material has been investigated theoretically. The electron density of the bunch is described by a Gauss distribution. Cherenkov radiation for the frequency range where the refractive index is negative is shown to lead to simultaneous excitation of both bulk and surface electromagnetic waves over one and the same frequency range. In this case the wave vector magnitude in the plane of the interface of surface electromagnetic waves is larger than the corresponding wave vector magnitude of bulk electromagnetic waves. The energy flows in a left-handed material have been calculated. The spectral density and the radiation pattern have been investigated

The Vavilov-Cherenkov radiation in a medium with a nonzero absorption coefficient

International Nuclear Information System (INIS)

Beshtoev, Kh.M.

1997-01-01

Distribution of the field around a charged relativistic particle in a medium is discussed. It is shown that the Vavilov-Cherenkov radiation exists in the case when the velocity of the charged particle is equal to the velocity of light in the medium. A simple approach is proposed to avoid singularity in the medium Electrodynamics

Cherenkov and anomalous Doppler effects in the relaxation of an electron beam

International Nuclear Information System (INIS)

Muschietti, L.; Appert, K.; Vaclavik, J.

1981-01-01

The interplay between the Cherenkov and anomalous Doppler interactions in the relaxation of a warm electron beam is investigated by numerical means. The most important feature in the interplay is found to be a nonelastic isotropization. A simple semianalytical model which allows one to estimate various quantities relevant to the relaxation process is also presented

Reflection Phenomena in Underground Pumped Storage Reservoirs

Directory of Open Access Journals (Sweden)

Elena Pummer

2018-04-01

Full Text Available Energy storage through hydropower leads to free surface water waves in the connected reservoirs. The reason for this is the movement of water between reservoirs at different elevations, which is necessary for electrical energy storage. Currently, the expansion of renewable energies requires the development of fast and flexible energy storage systems, of which classical pumped storage plants are the only technically proven and cost-effective technology and are the most used. Instead of classical pumped storage plants, where reservoirs are located on the surface, underground pumped storage plants with subsurface reservoirs could be an alternative. They are independent of topography and have a low surface area requirement. This can be a great advantage for energy storage expansion in case of environmental issues, residents’ concerns and an unusable terrain surface. However, the reservoirs of underground pumped storage plants differ in design from classical ones for stability and space reasons. The hydraulic design is essential to ensure their satisfactory hydraulic performance. The paper presents a hybrid model study, which is defined here as a combination of physical and numerical modelling to use the advantages and to compensate for the disadvantages of the respective methods. It shows the analysis of waves in ventilated underground reservoir systems with a great length to height ratio, considering new operational aspects from energy supply systems with a great percentage of renewable energies. The multifaceted and narrow design of the reservoirs leads to complex free surface flows; for example, undular and breaking bores arise. The results show excessive wave heights through wave reflections, caused by the impermeable reservoir boundaries. Hence, their knowledge is essential for a successful operational and constructive design of the reservoirs.

Rokibaar Underground = Rock bar Underground

Index Scriptorium Estoniae

2008-01-01

Rokibaari Underground (Küütri 7, Tartu) sisekujundus, mis pälvis Eesti Sisearhitektide Liidu 2007. a. eripreemia. Sisearhitekt: Margus Mänd (Tammat OÜ). Margus Männist, tema tähtsamad tööd. Plaan, 5 värv. vaadet, foto M. Männist

The underground economy in Romania

Directory of Open Access Journals (Sweden)

Adriana Veronica LITRA

2016-07-01

Full Text Available The paper aims at covering issues related to the underground economy, activities that compound this phenomenon, its magnitude in Romania and reported to the European average. Underground economy in Romania consists of undeclared work (2/3 from the total and unreported income; it decreased from 33.6% of GDP in 2003 to 28% in 2014, but remained over EU-28 average with about 10 p.p. Among EU-28 countries, only Bulgaria exceeds the size of the underground economy of Romania. The underground economy is a challenge for the leadership of the state which must act simultaneously to stop illegal activities, and to discourage non-declaration of the legal activities. Corruption favours maintaining the underground economy, delays economic development, obstructs democratic processes and affects justice and the law state.

Locating underground uranium deposits

International Nuclear Information System (INIS)

Felice, P.E.

1979-01-01

Underground uranium deposits are located by placing wires of dosimeters each about 5 to 18 mg/cm 2 thick underground in a grid pattern. Each dosimeter contains a phosphor which is capable of storing the energy of alpha particles. In each pair one dosimeter is shielded from alpha particles with more than 18 mg/cm 2 thick opaque material but not gamma and beta rays and the other dosimeter is shielded with less than 1 mg/cm 2 thick opaque material to exclude dust. After a period underground the dosimeters are heated which releases the stored energy as light. The amount of light produced from the heavily shielded dosimeter is subtracted from the amount of light produced from the thinly shielded dosimeter to give an indication of the location and quantity of uranium underground

Effect of geological medium on seismic signals from underground ...

Indian Academy of Sciences (India)

underground nuclear explosion event in a composite media with faults and complex ... faults, in situ stresses and tectonic strains, location of the free surface with respect .... at the elastic radius are the local geological formations, porosity, water con- ... the problem for a longer duration Sommerfeld (1949) radiation boundary ...

Massive Cherenkov neutrino facilities?their evolution, their future: Twenty-five years at these International Neutrino Conferences

International Nuclear Information System (INIS)

Sulak, Lawrence R.

2005-01-01

This review traces the evolution of massive water Cherenkov tracking calorimeters. Pioneering concepts, first presented in this conference a quarter of a century ago, have led to 1) IMB, the first large detector (10kT), which was designed primarily to search for proton decay, and secondarily to be sensitive to supernova neutrinos and atmospheric oscillations, and 2) Dumand, an attempt to initiate the search for TeV astrophysical neutrinos with a prototype for a 1 km 3 telescope. The concepts and initial work on IMB influenced subsequent detectors: Kamiokande, Super-K, SNO, and, in part, Kamland. These detectors have to their credit the elucidation of the physics of atmospheric, solar, reactor and supernova neutrinos. With the advent of the K2K beam, controlled accelerator neutrinos confirm the atmospheric studies. The path breaking developments of Dumand now are incorporated in the high-volume Amanda and Antares detectors, as well as their sequels, IceCube and the proposed Cubic Kilometer detector. The future (ultimate?) facilities have new physics challenges: A high-resolution megaton detector, eventually coupled with an intense accelerator neutrino source, is critical for precision studies of neutrino oscillation parameters and for the potential discovery of CP violation in the lepton sector. The Gigaton TeV neutrino telescopes (IceCube and Cubic Kilometer) seek to open high-energy neutrino astronomy, still an elusive goal. (Amanda, IceCube, and UNO, as well as Minos, Icarus and other large neutrino facilities using non-Cherenkov technologies, are treated in other contributions to this volume.)

Construction and performance of two multicell Cherenkov counters used in FRAMM-NA1 spectrometer

International Nuclear Information System (INIS)

Amendolia, S.R.; Batignani, G.; Bedeschi, F.; Bertolucci, E.; Bettoni, D.; Bosisio, L.; Bottigli, U.; Bradaschia, C.; Budinich, M.; Dell'Orso, M.; Fidecaro, F.; Foa, L.; Focardi, E.; Giazotto, A.; Giorgi, M.A.; Liello, F.; Marrocchesi, P.S.; Mensa, A.; Menzione, A.; Ristori, L.; Rolandi, L.; Scribano, A.; Stanga, R.; Stefanini, A.; Tonelli, G.

1983-01-01

Two small dimension multicell Cherenkov counters have been built for FRAMM-NA1 multiparticle spectrometer to identify pions and kaons in the momentum range between 5 and 22 GeV/c. The performances achieved and the construction details are reported. (orig.)

Real-time Cherenkov emission portal imaging during CyberKnife® radiotherapy

International Nuclear Information System (INIS)

Roussakis, Yiannis; Mason, Suzannah; Dehghani, Hamid; Zhang, Rongxiao; Heyes, Geoff; Webster, Gareth; Green, Stuart; Pogue, Brian

2015-01-01

The feasibility of real-time portal imaging during radiation therapy, through the Cherenkov emission (CE) effect is investigated via a medical linear accelerator (CyberKnife ® ) irradiating a partially-filled water tank with a 60 mm circular beam. A graticule of lead/plywood and a number of tissue equivalent materials were alternatively placed at the beam entrance face while the induced CE at the exit face was imaged using a gated electron-multiplying-intensified-charged-coupled device (emICCD) for both stationary and dynamic scenarios. This was replicated on an Elekta Synergy ® linear accelerator with portal images acquired using the iViewGT ™ system. Profiles across the acquired portal images were analysed to reveal the potential resolution and contrast limits of this novel CE based portal imaging technique and compared against the current standard. The CE resolution study revealed that using the lead/plywood graticule, separations down to 3.4  ±  0.5 mm can be resolved. A 28 mm thick tissue-equivalent rod with electron density of 1.69 relative to water demonstrated a CE contrast of 15% through air and 14% through water sections, as compared to a corresponding contrast of 19% and 12% using the iViewGT ™ system. For dynamic scenarios, video rate imaging with 30 frames per second was achieved. It is demonstrated that CE-based portal imaging is feasible to identify both stationary and dynamic objects within a CyberKnife ® radiotherapy treatment field. (note)

PEP cooling water systems and underground piped utilities design criteria report

International Nuclear Information System (INIS)

Hall, F.; Robbins, D.

1975-10-01

This paper discusses the cooling systems required by the PEP Storage Ring. Particular topics discussed are: Cooling tower systems, RF cavity and vacuum chamber LCW cooling systems, klystron and ring magnet LLW cooling systems, Injection magnet LCW Cooling Systems; PEP interaction area detector LCW Cooling Systems; and underground piped utilities. 1 ref., 20 figs

Process for fracturing underground formations

Energy Technology Data Exchange (ETDEWEB)

Kiel, O M

1974-01-25

This invention concerns a process for fracturing underground formations and has as one object the mixing of viscous compositions. Through a borehole, a fluid is injected into the formation. This fluid contains a complex prepared by the reaction of an aliphatic quaternary ammonium compound with a water-soluble compound chosen from monosaccharides, disaccharides, trisaccharides, polysaccharides, and synthetic hydroxylated polymers with long chains. These complexes are formed at temperatures between 20/sup 0/ and 205/sup 0/C. The process also includes production of formation fluid into the borehole.

The fluid systems for the SLD Cherenkov ring imaging detector

International Nuclear Information System (INIS)

Abe, K.; Hasegawa, K.; Hasegawa, Y.; Iwasaki, Y.; Suekane, F.; Yuta, H.; Baird, K.; Jacques, P.; Kalelkar, M.; Plano, R.; Stamer, P.; Word, G.; Bean, A.; Caldwell, D.O.; Duboscq, J.; Huber, J.; Lu, A.; Mathys, L.; McHugh, S.; Yellin, S.; Ben-David, R.; Manly, S.; Snyder, J.; Turk, J.; Cavalli-Sforza, M.; Coyle, P.; Coyne, D.; Gagnon, P.; Liu, X.; Schneider, M.; Williams, D.A.; Coller, J.; Shank, J.T.; Whitaker, J.S.; d'Oliveira, A.; Johnson, R.A.; Martinez, J.; Nussbaum, M.; Santha, A.K.S.; Sokoloff, M.D.; Stockdale, I.; Wilson, R.J.

1992-10-01

We describe the design and operation of the fluid delivery, monitor and control systems for the SLD barrel Cherenkov Ring Imaging Detector (CRID). The systems deliver drift gas (C 2 H 6 + TMAE), radiator gas (C 5 F 12 + N 2 ) and radiator liquid (C 6 F 14 ). Measured critical quantities such as electron lifetime in the drift gas and ultra-violet (UV) transparencies of the radiator fluids, together with the operational experience, are also reported

The new Tunka-133 EAS Cherenkov array: Status of 2009

International Nuclear Information System (INIS)

Antokhonov, B.V.; Beregnev, S.F.; Budnev, N.M.; Chvalaev, O.B.; Chiavassa, A.; Gress, O.A.; Kalmykov, N.N.; Karpov, N.N.; Korosteleva, E.E.; Kozhin, V.A.; Kuzmichev, L.A.; Lubsandorzhiev, B.K.; Mirgazov, R.R.; Panasyuk, M.I.; Pankov, L.V.; Prosin, V.V.; Ptuskin, V.S.; Semeney, Yu.A.; Shaibonov, B.; Silaev, A.A.

2011-01-01

The deployment of the new Extensive air shower Cherenkov installation Tunka-133 with about 1 km 2 geometric acceptance area was completed in October 2009. The array will permit a detailed long-term study of the cosmic ray energy spectrum and mass composition in the energy range 10 15 -10 18 eV with a unique and more elaborate method. The array construction and data acquisition system, preliminary results and plans for future development are presented.

Cherenkov-type diamond detectors for measurements of fast electrons in the TORE-SUPRA tokamak

International Nuclear Information System (INIS)

Jakubowski, L.; Sadowski, M. J.; Zebrowski, J.; Rabinski, M.; Malinowski, K.; Mirowski, R.; Lotte, Ph.; Gunn, J.; Pascal, J-Y.; Colledani, G.; Basiuk, V.; Goniche, M.; Lipa, M.

2010-01-01

The paper presents a schematic design and tests of a system applicable for measurements of fast electron pulses emitted from high-temperature plasma generated inside magnetic confinement fusion machines, and particularly in the TORE-SUPRA facility. The diagnostic system based on the registration of the Cherenkov radiation induced by fast electrons within selected solid radiators is considered, and electron low-energy thresholds for different radiators are given. There are some estimates of high thermal loads, which might be deposited by intense electron beams upon parts of the diagnostic equipment within the TORE-SUPRA device. There are some proposed measures to overcome this difficulty by the selection of appropriate absorption filters and Cherenkov radiators, and particularly by the application of a fast-moving reciprocating probe. The paper describes the measuring system, its tests, as well as some results of the preliminary measurements of fast electrons within TORE-SUPRA facility.

Interference effects on guided Cherenkov emission in silicon from perpendicular, oblique, and parallel boundaries

Science.gov (United States)

Couillard, M.; Yurtsever, A.; Muller, D. A.

2010-05-01

Waveguide electromagnetic modes excited by swift electrons traversing Si slabs at normal and oblique incidence are analyzed using monochromated electron energy-loss spectroscopy and interpreted using a local dielectric theory that includes relativistic effects. At normal incidence, sharp spectral features in the visible/near-infrared optical domain are directly assigned to p -polarized modes. When the specimen is tilted, s -polarized modes, which are completely absent at normal incidence, become visible in the loss spectra. In the tilted configuration, the dispersion of p -polarized modes is also modified. For tilt angles higher than ˜50° , Cherenkov radiation, the phenomenon responsible for the excitation of waveguide modes, is expected to partially escape the silicon slab and the influence of this effect on experimental measurements is discussed. Finally, we find evidence for an interference effect at parallel Si/SiO2 interfaces, as well as a delocalized excitation of guided Cherenkov modes.

Interference effects on guided Cherenkov emission in silicon from perpendicular, oblique, and parallel boundaries

International Nuclear Information System (INIS)

Couillard, M.; Yurtsever, A.; Muller, D. A.

2010-01-01

Waveguide electromagnetic modes excited by swift electrons traversing Si slabs at normal and oblique incidence are analyzed using monochromated electron energy-loss spectroscopy and interpreted using a local dielectric theory that includes relativistic effects. At normal incidence, sharp spectral features in the visible/near-infrared optical domain are directly assigned to p-polarized modes. When the specimen is tilted, s-polarized modes, which are completely absent at normal incidence, become visible in the loss spectra. In the tilted configuration, the dispersion of p-polarized modes is also modified. For tilt angles higher than ∼50 deg. Cherenkov radiation, the phenomenon responsible for the excitation of waveguide modes, is expected to partially escape the silicon slab and the influence of this effect on experimental measurements is discussed. Finally, we find evidence for an interference effect at parallel Si/SiO 2 interfaces, as well as a delocalized excitation of guided Cherenkov modes.

Cherenkov-type diamond detectors for measurements of fast electrons in the TORE-SUPRA tokamak

Energy Technology Data Exchange (ETDEWEB)

Jakubowski, L.; Sadowski, M. J.; Zebrowski, J.; Rabinski, M.; Malinowski, K.; Mirowski, R. [Andrzej Soltan Institute for Nuclear Studies (IPJ), Otwock-Swierk 05-400 (Poland); Lotte, Ph.; Gunn, J.; Pascal, J-Y.; Colledani, G.; Basiuk, V.; Goniche, M.; Lipa, M. [CEA, IRFM, St Paul-lez-Durance F-13108 (France)

2010-01-15

The paper presents a schematic design and tests of a system applicable for measurements of fast electron pulses emitted from high-temperature plasma generated inside magnetic confinement fusion machines, and particularly in the TORE-SUPRA facility. The diagnostic system based on the registration of the Cherenkov radiation induced by fast electrons within selected solid radiators is considered, and electron low-energy thresholds for different radiators are given. There are some estimates of high thermal loads, which might be deposited by intense electron beams upon parts of the diagnostic equipment within the TORE-SUPRA device. There are some proposed measures to overcome this difficulty by the selection of appropriate absorption filters and Cherenkov radiators, and particularly by the application of a fast-moving reciprocating probe. The paper describes the measuring system, its tests, as well as some results of the preliminary measurements of fast electrons within TORE-SUPRA facility.

Study of atmospheric neutrino interactions and search for nucleon decay in Soudan 2

Energy Technology Data Exchange (ETDEWEB)

Leeson, William R. [Tufts Univ., Medford, MA (United States)

1995-12-14

Contained event samples, including 30 single-track muon-like events, 35 single-shower electron-like events, and 34 multiprong events, have been obtained from a 1.0 kiloton-year exposure of the Soudan 2 detector. A sample of 15 multiprong events which are partially contained has also been isolated. Properties of these events are used to examine the verity of the atmospheric neutrino flavor ratio anomaly as reported by the Kamiokande and IMB-3 water Cherenkov experiments. The compatibility of the Soudan data with each of two `new physics` explanations for the anomaly, namely proton decay and neutrino oscillations, is investigated. We examine background processes which have not been explicitly treated by the water Cherenkov detectors. Chapters discuss underground non-accelerator particle physics, the atmospheric neutrino anomaly and its interpretation, the Soudan 2 detector and event selection, reconstruction of neutrino events, rock event contamination in Soudan `quasi-elastic` samples, contained multiprong events in Soudan 2, neutrino flavor composition of the multiprong sample, partially contained events in Soudan 2, nucleon decay in Soudan 2, and a summary and discussion.

Cherenkov effect as a probe of photonic nanostructures

International Nuclear Information System (INIS)

Garcia de Abajo, F.J.; Pattantyus-Abraham, A.G.; Wolf, M.O.; Zabala, N.; Rivacoba, A.; Echenique, P.M.

2003-01-01

Electron energy-loss spectroscopy (EELS) is shown to be an excellent source of information both on photonic crystal bands and on radiation modes of complex nanostructures. Good agreement is reported between measurements and parameter-free calculations of EELS in porous alumina films, where Cherenkov radiation is scattered by the pores to yield a strong 8.3-eV (7-eV) feature for 120-keV (200-keV) electrons. The latter is related to the bands of two-dimensional photonic crystals formed by air cylinders in an alumina matrix with similar near-range ordering. Finally, the band structure is proved to be directly mapped by angle-resolved EELS

THGEM based photon detector for Cherenkov imaging applications

CERN Document Server

Alexeev, M; Bradamante, F; Bressan, A; Chiosso, M; Ciliberti, P; Croci, G; Colantoni, M L; Dalla Torre, S; Duarte Pinto, S; Denisov, O; Diaz, V; Ferrero, A; Finger, M; Finger, M Jr; Fischer, H; Giacomini, G; Giorgi, M; Gobbo, B; Heinsius, F H; Herrmann, F; Jahodova, V; Königsmann, K; Lauser, L; Levorato, S; Maggiora, A; Martin, A; Menon, G; Nerling, F; Panzieri, D; Pesaro, G; Polak, J; Rocco, E; Ropelewski, L; Sauli, F; Sbrizzai, G; Schiavon, P; Schill, C; Schopferer, S; Slunecka, M; Sozzi, F; Steiger, L; Sulc, M; Takekawa, S; Tessarotto, F; Wollny, H

2010-01-01

We are developing a single photon detector for Cherenkov imaging counters. This detector is based on the use of THGEM electron multipliers in a multilayer design. The major goals of our project are ion feedback suppression down to a few per cent, large gain, fast response, insensitivity to magnetic fields, and a large detector size. We report about the project status and perspectives. In particular, we present a systematic study of the THGEM response as a function of geometrical parameters, production techniques and the gas mixture composition. The first figures obtained from measuring the response of a CsI coated THGEM to single photons are presented.

Geological investigations for geological model of deep underground geoenvironment at the Mizunami Underground Research Laboratory (MIU)

International Nuclear Information System (INIS)

Tsuruta, Tadahiko; Tagami, Masahiko; Amano, Kenji; Matsuoka, Toshiyuki; Kurihara, Arata; Yamada, Yasuhiro; Koike, Katsuaki

2013-01-01

Japan Atomic Energy Agency (JAEA) is performing a geoscientific research project, the Mizunami Underground Research Laboratory (MIU) project, in order to establish scientific and technological basis for geological disposal of high-level radioactive wastes. The MIU is located in crystalline rock environment, in Mizunami City, central Japan. Field investigations include geological mapping, reflection seismic surveys, several borehole investigations and geological investigations in the research galleries to identify the distribution and heterogeneity of fractures and faults that are potential major flowpaths for groundwater. The results of these field investigations are synthesized and compiled for the purpose of geological modeling. The field investigations indicate that the Main Shaft at the MIU intersected low permeability NNW oriented faults. A high permeability fracture zone in the granite, a significant water inflow point, was observed in the Ventilation Shaft. Development of the geological model focusing 3D spatial relationships at different scales and evolution of the geoenvironment are underway. This paper describes geological investigations applied in the MIU project, focusing on the evaluation of their effectiveness to understand for deep underground geoenvironment. (author)

Acidity decay of above-drainage underground mines in West Virginia.

Science.gov (United States)

Mack, B; McDonald, L M; Skousen, J

2010-01-01

Acidity of water from abandoned underground mines decreases over time, and the rate of decrease can help formulate remediation approaches and treatment system designs. The objective of this study was to determine an overall acidity decay rate for above-drainage underground mines in northern West Virginia from a large data set of mines that were closed 50 to 70 yr ago. Water quality data were obtained from 30 Upper Freeport and 7 Pittsburgh coal seam mines in 1968, 1980, 2000, and 2006, and acidity decay curves were calculated. The mean decay constant, k, for Upper Freeport mines was 2.73 x 10(-2) yr(-1), with a 95% confidence interval of +/- 0.0052, whereas the k value for Pittsburgh mines was not significantly different at 4.26 x 10(-2) yr(-1) +/- 0.017. Acidity from the T&T mine, which was closed 12 yr ago, showed a k value of 11.25 x 10(-2) yr(-1). This higher decay rate was likely due to initial flushing of accumulated metal salts on reaction surfaces in the mine, rapid changes in mine hydrology after closure, and treatment. Although each site showed a specific decay rate (varying from 0.04 x 10(-2) yr(-1) to 13.1 x 10(-2) yr(-1)), the decay constants of 2.7 x 10(-2) yr(-1) to 4.3 x 10(-2) yr(-1) are useful for predicting water quality trends and overall improvements across a wide spectrum of abandoned underground mines. We found first-order decay models improve long-term prediction of acidity declines from above-drainage mines compared with linear or percent annual decrease models. These predictions can help to select water treatment plans and evaluate costs for these treatments over time.

Analysis of the Causes of Cracks in the Bottom Floor of the Underground Garage of the Hefei Government Affairs Center by using 3D Finite-Element Analysis

Directory of Open Access Journals (Sweden)

ZHU Lei

2015-09-01

Full Text Available A three-dimensional finite-element software program is used in this study to analyze the causes of cracks in an underground garage. Numerous cracks, serious and regular alike, can be found in the underground garage of the Hefei Government Affairs Center. These cracks are mainly located around the central part of the bottom floor within a 44.6– 57.8 m radius. To explore the causes of the cracks, two attempts are made. On one hand, on-site crack detection and underground water monitoring are conducted. On the other hand, the finite-element software program ANSYS is adopted to establish a finite-element model for the floor–foundation and connecting beam–foundation soil systems of the underground garage. Furthermore, the influences of the underground foundation, underground water level, soil expansion, and Poisson ratio on the bottom floor are calculated and analyzed. On the basis of the calculation and monitoring results, the following conclusion can be made: underground water is the main cause of the bottom floor cracks because underground water exerts a pushing force from the bottom and causes the expansibility of expansive soil. The study aims to provide a theoretical basis for the treatment of cracking in the Hefei Government Affairs Center, and offer a reference for the design, construction, and maintenance of similar projects.

The use of an ultra-violet camera in the atmospheric Cherenkov technique

International Nuclear Information System (INIS)

Urban, M.; Fleury, P.; Kerrick, A.D.; Pare, E.; Vacanti, G.

1996-01-01

The atmospheric Cherenkov technique for gamma ray astronomy is shown to be feasible using an ultraviolet (UV) camera on moon-lit-nights. The Whipple telescope has been used as the reflector and the CRab Nebula as the standard gamma ray beam. Our energy threshold is 1.2 TeV which is compared to 0.4 TeV in the visible. (orig.)

CELESTE an atmospheric Cherenkov telescope for high energy gamma astrophysics

CERN Document Server

Paré, E; Bazer-Bachi, R; Bergeret, H; Berny, F; Briand, N; Bruel, P; Cerutti, M; Collon, J; Cordier, A; Cornebise, P; Debiais, G; Dezalay, J P; Dumora, D; Durand, E; Eschstruth, P T; Espigat, P; Fabre, B; Fleury, P; Gilly, J; Gouillaud, J C; Gregory, C; Herault, N; Holder, J; Hrabovsky, M; Incerti, S; Jouenne, A; Kalt, L; Legallou, R; Lott, B; Lodygensky, O; Manigot, P; Manseri, H; Manitaz, H; Martin, M; Morano, R; Morineaud, G; Muenz, F; Musquere, A; Naurois, M D; Neveu, J; Noppe, J M; Olive, J F; Palatka, M; Pérez, A; Quebert, J; Rebii, A; Reposeur, T; Rob, L; Roy, P; Sans, J L; Sako, T; Schovanek, P; Smith, D A; Snabre, P; Villard, G

2002-01-01

CELESTE is an atmospheric Cherenkov telescope based on the sampling method which makes use of the de-commissioned THEMIS solar electrical plant in the French Pyrenees. A large (2000 m sup 2) mirror surface area from 40 independent heliostats followed by a secondary optic, a trigger system using analog summing techniques and signal digitization with 1 GHz flash ADCs make possible the detection of cosmic gamma-rays down to 30 GeV. This paper provides a detailed technical description of the CELESTE installation.

Evaluation of underground water contamination of tubular wells, by fuels oil in Santo Andre City, Sao Paulo state: a contribution to the environmental management

International Nuclear Information System (INIS)

Mindrisz, Ana Copat

2006-01-01

The contamination of underground waters by hydrocarbons originated from gas stations has been object of increasing preoccupation in environmental organization all over the world. The organic compounds Benzene, Toluene, Ethylbenzene and Xylene (BTEX), present in these fuels, are extremely toxic to human health and could make impracticable the exploration of these contaminated waters by these kinds of pollutants and consequently the gasoline wells used for this purpose. In this work, it was carried out a diagnosis of the water quality with information and analyses, with the goals to snap shot the situation of the wells destined to domestic and commercial supply of water in the urban area of Santo Andre city, Sao Paulo state. There have been evaluated the presence of micron pollutants BTEX, after contamination due to leaks in fuel storage tanks close to the wells, in different places of the city. The physical chemistry parameters like color, turbidity and residual chlorine were also evaluated as well as trace elements, metals, anions like fluorine, sulphates, chlorine, nitrates and phosphates and bacteriological (total coliforms, thermo stable coliforms, heterotrophic bacteria). On definition of the sampling area, it was sought, at first, the evaluation of environmental contaminations historical series by gas stations, evaluating the set of information available at government environmental organizations and spatial representatively of the problem. For administration of the underground water quality it was adopted the methodology used by Companhia de Tecnologia de Saneamento Ambiental (CETESB), being accomplished a previous identification of contaminated potential areas and organizing a data base on landfills disposal and neglected places; registration of gas station services and, wells used by the population, industrial inventory with active and neglected maps taking into consideration the size and residues generation (such as SEMASA), prioritizing in this way the

A Cherenkov radiator for FEL-synchronized VUV-pulses at a linac-based FEL

NARCIS (Netherlands)

Goloviznin, V. V.; Oepts, D.; van der Wiel, M. J.

1997-01-01

A possible way to carry out two-color IR+VUV pump-probe experiments at linac-based FELs is proposed. The idea is to supply an FEL facility with a gas cell filled with helium or hydrogen, so that the electron beam, upon passage through the undulator, could be used to generate ultraviolet Cherenkov

A Cherenkov radiator for FEL-synchronized VUV-pulses at a linac-based FEL

NARCIS (Netherlands)

Goloviznin, V.V.; Oepts, W.; Wiel, van der M.J.

1997-01-01

A possible way to carry out two-color IR + VUV pump-probe experiments at linac-based FELs is proposed. The idea is to supply an FEL facility with a gas cell filled with helium or hydrogen, so that the electron beam, upon passage through the undulator, could be used to generate ultraviolet Cherenkov

Underground risk management information systems

Energy Technology Data Exchange (ETDEWEB)

Matsuyama, S.; Inoue, M.; Sakai, T.

2006-03-15

JCOAL has conducted Joint Research on an Underground Communication and Risk Management Information System with CSIRO of Australia under a commissioned study project for the promotion of coal use starting in fiscal 2002. The goal of this research project is the establishment of a new Safety System focusing on the comprehensive risk management information system by the name of Nexsys. The main components of the system are the Ethernet type underground communication system that represents the data communication base, and the risk management information system that permits risk analysis in real-time and provides decision support based on the collected data. The Nexsys is an open system and is a core element of the underground monitoring system. Using a vast amount of underground data, it is capable of accommodating a wide range of functions that were not available in the past. Because of it, it is possible to construct an advanced underground safety system. 14 figs., 4 tabs.

Comparison between disign criteria and observed structural performance of underground openings at WIPP

International Nuclear Information System (INIS)

Cook, R.F.; Francke, C.

1989-01-01

This paper discusses the observed structural performance of the underground excavations at the Waste Isolation Pilot Plant (WIPP) in relation to design criteria. The criteria were established at an early stage of the project to define the functional and structural requirements that were to be addressed in the design of the facility. For the underground structural response, the criteria defined the requirements for the shaft and shaft liner design, mine design, waste emplacement, retrievability and instrumentation. The observed structural performance of the underground is determined by the field data that have been collected since excavations were started at the WIPP site. The observations include field measurements of rock and water conditions, as well as maintenance records. The data provide input to design confirmation, performance assessment and form the basis for the design of new underground structures. For this paper, the field data have been compared with the design criteria applicable to ground control to demonstrate that the requirements of the design are met

Application of the chain saw machine for underground quarry

Energy Technology Data Exchange (ETDEWEB)

Lim, Han-Uk; Baek, Hwan-Jo [Kangwon National University, Chuncheon(Korea); Kim, Chi-Hwan [Woosuk University, Wonju(Korea); Kim, Tae-Soo [Sungshin Mining Co., Jungseun(Korea)

2001-10-31

Many regulatory activities for preservation of the environment make it recently difficult for the stone industry in our country. To reduce environmental hazards and to conserve original surface and woods, some effective underground methods must be adopted. Some new techniques such as chain saw machine, diamond wire saw and water jet cutting can be considered. But application of chain saw machine for underground quarry is proposed in this study. Some technical adoptions with chain saw were carried out at Jungseun marble mine. It is proved that this machine can be effectively adopted to cut dimension stone. With chain saw and diamond wire saw, it can be expected to achieve more effectively cutting the dimension stone. (author). 6 refs., 3 tabs., 6 figs.

30 CFR 75.804 - Underground high-voltage cables.

Science.gov (United States)

2010-07-01

... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Underground high-voltage cables. 75.804 Section...

Sanford Underground Research Facility - The United State's Deep Underground Research Facility

Science.gov (United States)

Vardiman, D.

2012-12-01

The 2.5 km deep Sanford Underground Research Facility (SURF) is managed by the South Dakota Science and Technology Authority (SDSTA) at the former Homestake Mine site in Lead, South Dakota. The US Department of Energy currently supports the development of the facility using a phased approach for underground deployment of experiments as they obtain an advanced design stage. The geology of the Sanford Laboratory site has been studied during the 125 years of operations at the Homestake Mine and more recently as part of the preliminary geotechnical site investigations for the NSF's Deep Underground Science and Engineering Laboratory project. The overall geology at DUSEL is a well-defined stratigraphic sequence of schist and phyllites. The three major Proterozoic units encountered in the underground consist of interbedded schist, metasediments, and amphibolite schist which are crosscut by Tertiary rhyolite dikes. Preliminary geotechnical site investigations included drift mapping, borehole drilling, borehole televiewing, in-situ stress analysis, laboratory analysis of core, mapping and laser scanning of new excavations, modeling and analysis of all geotechnical information. The investigation was focused upon the determination if the proposed site rock mass could support the world's largest (66 meter diameter) deep underground excavation. While the DUSEL project has subsequently been significantly modified, these data are still available to provide a baseline of the ground conditions which may be judiciously extrapolated throughout the entire Proterozoic rock assemblage for future excavations. Recommendations for facility instrumentation and monitoring were included in the preliminary design of the DUSEL project design and include; single and multiple point extensometers, tape extensometers and convergence measurements (pins), load cells and pressure cells, smart cables, inclinometers/Tiltmeters, Piezometers, thermistors, seismographs and accelerometers, scanners (laser

Real-time track-less Cherenkov ring fitting trigger system based on Graphics Processing Units

Science.gov (United States)

Ammendola, R.; Biagioni, A.; Chiozzi, S.; Cretaro, P.; Cotta Ramusino, A.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Gianoli, A.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P. S.; Pastorelli, E.; Piandani, R.; Piccini, M.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.; Vicini, P.

2017-12-01

The parallel computing power of commercial Graphics Processing Units (GPUs) is exploited to perform real-time ring fitting at the lowest trigger level using information coming from the Ring Imaging Cherenkov (RICH) detector of the NA62 experiment at CERN. To this purpose, direct GPU communication with a custom FPGA-based board has been used to reduce the data transmission latency. The GPU-based trigger system is currently integrated in the experimental setup of the RICH detector of the NA62 experiment, in order to reconstruct ring-shaped hit patterns. The ring-fitting algorithm running on GPU is fed with raw RICH data only, with no information coming from other detectors, and is able to provide more complex trigger primitives with respect to the simple photodetector hit multiplicity, resulting in a higher selection efficiency. The performance of the system for multi-ring Cherenkov online reconstruction obtained during the NA62 physics run is presented.

Front-end electronics and data acquisition system for imaging atmospheric Cherenkov telescopes

International Nuclear Information System (INIS)

Chen, Y.T.; La Taille, C. de; Suomijärvi, T.; Cao, Z.; Deligny, O.; Dulucq, F.; Ge, M.M.; Lhenry-Yvon, I.; Martin-Chassard, G.; Nguyen Trung, T.; Wanlin, E.; Xiao, G.; Yin, L.Q.; Yun Ky, B.; Zhang, L.; Zhang, H.Y.; Zhang, S.S.; Zhu, Z.

2015-01-01

In this paper, a front-end electronics based on an application-specific integrated circuit (ASIC) is presented for the future imaging atmospheric Cherenkov telescopes (IACTs). To achieve this purpose, a 16-channel ASIC chip, PARISROC 2 (Photomultiplier ARray Integrated in SiGe ReadOut Chip) is used in the analog signal processing and digitization. The digitized results are sent to the server by a user-defined User Datagram Protocol/Internet Protocol (UDP/IP) hardcore engine through Ethernet that is managed by a FPGA. A prototype electronics fulfilling the requirements of the Wide Field of View Cherenkov Telescope Array (WFCTA) of the Large High Altitude Air Shower Observatory (LHAASO) project has been designed, fabricated and tested to prove the concept of the design. A detailed description of the development with the results of the test measurements are presented. By using a new input structure and a new configuration of the ASIC, the dynamic range of the circuit is extended. A highly precise-time calibrating algorithm is also proposed, verified and optimized for the mass production. The test results suggest that the proposed electronics design fulfills the general specification of the future IACTs

Front-end electronics and data acquisition system for imaging atmospheric Cherenkov telescopes

Energy Technology Data Exchange (ETDEWEB)

Chen, Y.T., E-mail: chenytao@ynu.edu.cn [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Yunnan University, 650091 Kunming (China); La Taille, C. de [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Suomijärvi, T. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Cao, Z. [Institute of High Energy Physics, 100049 Beijing (China); Deligny, O. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Dulucq, F. [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Ge, M.M. [Yunnan University, 650091 Kunming (China); Lhenry-Yvon, I. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Martin-Chassard, G. [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Nguyen Trung, T.; Wanlin, E. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Xiao, G.; Yin, L.Q. [Institute of High Energy Physics, 100049 Beijing (China); Yun Ky, B. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Zhang, L. [Yunnan University, 650091 Kunming (China); Zhang, H.Y. [Tsinghua University, 100084 Beijing (China); Zhang, S.S.; Zhu, Z. [Institute of High Energy Physics, 100049 Beijing (China)

2015-09-21

In this paper, a front-end electronics based on an application-specific integrated circuit (ASIC) is presented for the future imaging atmospheric Cherenkov telescopes (IACTs). To achieve this purpose, a 16-channel ASIC chip, PARISROC 2 (Photomultiplier ARray Integrated in SiGe ReadOut Chip) is used in the analog signal processing and digitization. The digitized results are sent to the server by a user-defined User Datagram Protocol/Internet Protocol (UDP/IP) hardcore engine through Ethernet that is managed by a FPGA. A prototype electronics fulfilling the requirements of the Wide Field of View Cherenkov Telescope Array (WFCTA) of the Large High Altitude Air Shower Observatory (LHAASO) project has been designed, fabricated and tested to prove the concept of the design. A detailed description of the development with the results of the test measurements are presented. By using a new input structure and a new configuration of the ASIC, the dynamic range of the circuit is extended. A highly precise-time calibrating algorithm is also proposed, verified and optimized for the mass production. The test results suggest that the proposed electronics design fulfills the general specification of the future IACTs.

Studies on engineering technologies in the Mizunami Underground Research Laboratory. FY 2007 (Contract research)

International Nuclear Information System (INIS)

Noda, Masaru; Suyama, Yasuhiro; Nobuto, Jun; Ijiri, Yuji; Mikake, Shinichiro; Matsui, Hiroya

2009-07-01

The Mizunami Underground Research Laboratory (MIU) of the Japan Atomic Energy Agency is a major site for geoscientific research to advance the scientific and technological basis for geological disposal of high-level radioactive waste in crystalline rock. Studies on relevant engineering technologies in the MIU consist of a) research on design and construction technology for very deep underground applications, and b) research on engineering technology as a basis of geological disposal. In the Second Phase of the MIU project (the construction phase), engineering studies have focused on research into design and construction technologies for deep underground. The main subjects in the study of very deep underground structures consist of the following: 'Demonstration of the design methodology', 'Demonstration of existing and supplementary excavation methods', 'Demonstration of countermeasures during excavation' and 'Demonstration of safe construction'. In the FY 2007 studies, identification and evaluation of the subjects for study of engineering technologies in the construction phase were carried out to optimize future research work. Specific studies included: validation of the existing design methodology based on data obtained during construction; validation of existing and supplementary rock excavation methods for very deep shafts; estimation of rock stability under high differential water pressures, methodology on long-term maintenance of underground excavations and risk management systems for construction of underground structures have been performed. Based on these studies, future research focused on the four subject areas, which are 'Demonstration of the design methodology', 'Demonstration of existing and supplementary excavation methods', 'Demonstration of countermeasures during excavation' and 'Demonstration of safe construction', has been identified. The design methodology in the first phase of the MIU Project (surface-based investigation phase) was verified to