Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Multiwire proportional chamber


Related Topics

In the News (Mon 16 Nov 09)

  
  Apparatus and method for reading two-dimensional electrophoretograms containing .beta.-ray-emitting labeled compounds ...
A single, flat rectangular multiwire proportional chamber is placed in close proximity to the gel and the assembly placed in an intense uniform magnetic field disposed in a perpendicular manner to the rectangular face of the proportional chamber.
Beta rays emitted in the direction of the proportional chamber are caused to execute helical motions which substantially preserve knowledge of the coordinates of their origin in the gel.
Collisions of the.beta.-rays with gas molecules encountered in the proportional chamber slow these energetic particles down and the helical patterns tend to have decreasing radii as the.beta.-rays progress through the proportional chamber, thereby preserving, to a large extend, the location of the origin of the individual.beta.-ray emissions.
www.freepatentsonline.com /4686368.html   (4369 words)

  
 Medical imaging device using low-dose X- or gamma ionizing radiation - Patent 5521956
The chambers comprise, arranged in a direction orthogonal to the plane containing the slit and the sheet-form illumination beam, a drift space for the electrons, comprising a first cathode electrode, and an electron proportional multiplier grid for generating multiplied electrons and corresponding ions.
The multiwire chamber furthermore comprises, in the vicinity of the proportional multiplier grid, but downstream thereof, in the drift direction of the electrons originating from the drift space, a second electrode forming a cathode electrode for the ions corresponding to the multiplied electrons generated by the proportional amplification phenomenon.
Similarly, it is indicated that, the proportional multiplier grid 13 being itself formed by a succession of parallel electrically conductive wires fulfilling the successive function of alternate amplification cathodes and anodes, a negative potential with respect to the anode wires is applied to the amplification cathode wires, the wires C in FIG.
www.freepatentsonline.com /5521956.html   (3937 words)

  
 Wire chamber - Wikipedia, the free encyclopedia
A multi-wire chamber (or just wire chamber) is a detector for particles of ionizing radiation which is an advancement of the concept of the Geiger counter and the proportional counter.
(In bubble chambers, photographs were made, printed and then looked through.) A wire chamber is a chamber with many parallel wires, arranged as a grid and put on high voltage, with the metal casing being on ground potential.
This greatly increases the accuracy of the path reconstruction and is known as a drift chamber.
en.wikipedia.org /wiki/Multiwire_proportional_chamber   (549 words)

  
 Speaker Information
Unlike earlier detectors, such as the bubble chamber, which can record the tracks left by particles at the rate of only one or two per second, the multiwire chamber records up to one million tracks per second and sends the data directly to a computer for analysis.
The speed and precision of the multiwire chamber and its descendants, the drift chamber and the time projection chamber, revolutionized high-energy physics.
Samuel Ting's discovery of the J/psi particle and Carlo Rubbia's discovery of the W and Z particles, which won Nobel Prizes in 1976 and 1984, respectively, involved the use of multiwire chambers; and by the 1990s such detectors were at the heart of almost every experiment in particle physics.
www.bibalex.org /bioalex2006conf/SpeakerInfo.aspx?ID=329   (229 words)

  
 Multiwire Proportional Chambers
A multiwire proportional chamber (MWPC) is constructed with alternating planes of high voltage wires and sense wires, which are at ground.
All five chambers operate with a gas mixture of 75% argon and 25% ethane bubbled through methyl alcohol.
The positions and construction of the five chambers are summarized in spec:pwc_internals.
www-focus.fnal.gov /people/ewv/thesis/html/node35.html   (385 words)

  
 Drift Chamber
  A multiwire chamber in which spatial resolution is achieved by measuring the time electrons need to reach the anode wire, measured from the moment that the ionizing particle traversed the detector.
Drift chambers use longer drift distances, hence are slower than multiwire chambers; therefore, they are typically not used in the primary beam, in high-rate colliders, or for triggering purposes.
Drift chambers have been built in many different forms and sizes, and they are standard tracking detectors in more or less all experiments; this is true even in high-rate colliders, where the collision rate can be shorter than the maximum drift time.
rkb.home.cern.ch /rkb/PH14pp/node50.html   (716 words)

  
 Press Release: The 1992 Nobel Prize in Physics
The break-through occurred with Charpak's invention of the multiwire proportional chamber.
For the development of the cloud chamber, which registers tracks of charged particles in a gas, the 1927 Nobel Prize was awarded to C.T.R. Wilson.
During the 1960's a large number of new elementary particles were discovered thanks to the bubble chamber technique and L.W. Alvarez was awarded the 1968 Nobel Prize in physics for the development of this technique.
nobelprize.org /nobel_prizes/physics/laureates/1992/press.html   (1338 words)

  
 Introduction   (Site not responding. Last check: 2007-10-10)
The limitations of multiwire proportional chambers concerning spatial resolution and velocity of signal development together with the high demands of expected particle rates at future particle accelerators required the invention of a new detector based on particle detection in gas.
To improve the spatial resolution compared to multiwire proportional chambers the distances between the anode wires have to be decreased.
The major advantage of MSGCs compared to multiwire proportional chambers is the availability of 70% of the induced charge after approx.
www.physik.rwth-aachen.de /group/IIIphys/CMS/tracker/msgc/introduction.html   (642 words)

  
 New Page 1
Its basic components are a lithium Floride radiator, a gas chamber and a multiwire proportional chamber (photon detector).
The gas chamber is used to filter some of the background noises and reduce the number of unknown variables.
The multi-wire proportional chamber is used to convert the photons into measurable electronic pulses.
mxp.physics.umn.edu /s99/Projects/multiwpc/rich.htm   (136 words)

  
 Georges Charpak Summary
The multiwire proportional chamber replaced the single positively charged wire of the Geiger-Muller tube, which attracts electrons in a chamber of ionized gas, with a multiwire device.
The cloud chamber and the bubble chamber were two earlier inventions that had received recognition from the academy.
In the field of medicine, his chamber is able to analyze the structure of a protein with X rays a thousand times faster than was previously possible.
www.bookrags.com /Georges_Charpak   (1837 words)

  
 LeCroy PCOS4 Data Sheet
Proportional chambers are one of the workhorses of particle physics experiments.
Since the 2741 cards must plug in to both the proportional chamber and the readout backplane, the backplane must be designed to match exactly the connector spacing of the proportional chamber.
To reduce the possibility of noise conducted to the chambers by the readout cables, there are no continuously running clocks between the controller boards and the front end cards.
www.lecroy.com /lrs/dsheets/pcos4.htm   (2465 words)

  
 3.5.3  Multiwire Proportional Chambers   (Site not responding. Last check: 2007-10-10)
A multiwire proportional chamber is a dispositive like the one that the Figure 9 shows.
The planes of wires inside the atmosphere, is the operation key for the chambers.
The argon isobutane is used as the active gas in the chambers.
fisica.usac.edu.gt /public/curccaf_proc/felix/node16.html   (193 words)

  
 Observing the World of Particles
With the multiwire chamber the data handling capacity increased dramatically.
The original particle going through the chamber gives rise to a signal on a nearby wire which is proportional to the amount of ions that is created.
The multiwire proportional chamber consists of several cathode planes and several planes of parallel anode wires of different orientation.
nobelprize.org /educational_games/physics/observing/multiwire-2.html   (147 words)

  
 The 1995/1996 design
Electrons liberated in the silicon by fast particles traversing the detector drift radially, towards the outer edge of the chamber, which consists of an array of 360 anodes, where the electrons are collected.
The Pad Chamber is a multiwire proportional chamber (MWPC) with pad read-out.
The chamber is placed behind the mirror of RICH-2, at a distance of ~3.3 m from the target.
www.weizmann.ac.il /home/cherlin/d95.html   (1166 words)

  
 Multi-Wire Proportional Chambers of SALAD   (Site not responding. Last check: 2007-10-10)
A multiwire proportional chamber basically of a set of thin, equally spaced anode wires placed symmetrically between two cathode planes.
The active area of the small chamber is 380mm x 380mm, that of the large chamber 840mm x 840mm.
The second chamber is designed such that it can be used later for measurements of the polarization of the outgoing protons, which requires large angle secondary scattering.
www.kvi.nl /~salad/old_salad/mwpc.html   (693 words)

  
 Right/left assignment in drift chambers and proportional multiwire chambers (PWC's) using induced signals (US4179608)
Improved multiwire chamber having means for resolving the left/right ambiguity in the location of an ionizing event.
The chamber includes a plurality of spaced parallel anode wires positioned between spaced planar cathodes.
An improved multiwire chamber for the detection and localization of ionizing radiation and having a plurality of anode wires wherein the improvement comprises:
www.delphion.com /details?pn10=US04179608   (329 words)

  
 Amazon.com: "proportional chamber": Key Phrase page   (Site not responding. Last check: 2007-10-10)
What was missing was the understanding of the pulse formation mech- anism in a multiwire proportional chamber: the pulses on the anode wires are not due to the collection of the electrons of the avalanches, but to...
3 Measurement of position 3.1 Multiwire proportional chamber In a proportional chamber, the principle of a proportional counter (section 2.2) is applied to a detector with large area.
As area electronic detectors, one often uses proportional chambers with numerous wires [5.30, 35] proportional chamber with spherical drift gaps [5.
www.amazon.com /phrase/proportional-chamber   (547 words)

  
 Science in Poland - Georges Charpak   (Site not responding. Last check: 2007-10-10)
In particular, his development of the multiwire proportional chamber in the 1960's allowed the trajectories of particles issuing from high-energy collisions to be tracked with a spatial precision of less than 1 mm.
These characteristics of Charpak's detector - high spatial resolution and high repetition rate - were particularly important in the study of rare interactions or the creation of short-lived exotic particles which often necessitate the use of intense beams and the sampling of a large number of events in a short period of time.
Samuel Ting's discovery of the J/psi meson and Carlo Rubbia's discovery of the W and Z particles, which won Nobel Prizes in 1976 and 1984, respectively, involved the use of multiwire chambers; and by the 1990s such detectors were at the heart of almost every experiment in particle physics.
www.staff.amu.edu.pl /~zbzw/ph/sci/gc.htm   (587 words)

  
 Z-coordinate Chamber   (Site not responding. Last check: 2007-10-10)
The Z chamber[105] is a double layer multiwire proportional chamber with anode and cathode readout mounted just outside the drift chamber between three concentric cylindrical fiberglass shells with diameters less than 5 cm apart: 612.8, 630.5, and 647.7 mm.
The longitudinal length of the cylinders is 800 mm to be compared to the drift chamber length of 440 mm because the Z chamber participates in the trigger.
Jewel-tipped pins identical to those for the drift chamber are inserted in these holes to hold the anode wires.
hep.bu.edu /~brown/phd/node36.html   (245 words)

  
 CERN Courier - Micropattern detectors promi - IOP Publishing - article
Georges Charpak's 1968 invention of the multiwire proportional chamber (MWPC) ushered in a new era, with a major impact on high-energy physics.
In the case of microstrip detectors, the anode-cathode distance is small compared with that in a wire chamber, and, with electric fields at the tip of the streamer and along the surface being high, the streamer is likely to be followed by a voltage- and ionization density-dependent discharge.
A very asymmetric parallel plate chamber, the MICROMEGAS detector invented by Charpak and Giomataris, takes advantage of the behaviour at high fields (100 kV/cm) in several gas mixtures, thus achieving stable operation with the minimum of ionizing particles at high gains and rates.
www.cerncourier.com /main/article/41/2/13   (1006 words)

  
 Term-Papers.us - Georges Charpac   (Site not responding. Last check: 2007-10-10)
In particular, his development of the multiwire proportional chamber in the 1960's allowed the path of particles issuing from high-energy collisions to be tracked with a spatial precision of less than 1 mm.
Additionally, the rate at which the chamber could make a measurement, recover, and then be able to make a new measurement grew to be many thousands per second.
These characteristics of Charpak's detector - high spatial resolution and high repetition rate - were particularly important in the study of rare interactions or the creation of short-lived exotic particles which often require the use of intense beams and the sampling of a large number of events in a short period of time.
www.term-papers.us /ts/ha/skx102.shtml   (582 words)

  
 The Scientist : Citation Records Underscore Nobel Winners' Long-Standing Influence On Lab Research
Georges Charpak, a 68-year-old French physicist who has been at CERN since 1959, was awarded the Nobel Prize in physics for his development of particle detectors, in particular the 1968 invention of the multiwire proportional chamber, a device that gave rise to most of the detectors in use at accelerator facilities today.
But, as is typical of the field of physics, his citation record is not nearly as showy as those of the other three scientific awardees.
His seminal 1968 paper, "Multiwire proportional counters to select and localize charged particles" (G. Charpak, et al., Nuclear Instruments & Methods in Physics, 62:262, 1968), has been cited 122 times since its publication, with the number of annual citations peaking at 18 in 1971.
www.the-scientist.com /article/display/11614   (1024 words)

  
 Multiwire Chamber
Simple multiwire chambers are used as tracking chambers, with the anode wires only giving one bit of information for a passing particle.
These chambers are characterized by comparatively longer drift times; multiple sense wires can cover a large volume, and are usually equipped with multihit electronics, such that the passage of several tracks in the volume part associated with a wire can be recorded.
These chambers give inherently two-dimensional information (the drift time is in a coordinate orthogonal to the wire plane).
rd11.web.cern.ch /RD11/rkb/PH14pp/node121.html   (554 words)

  
 Chronologie CERN/W.Pauli
The invention of multiwire proportional chambers and drift chambers revolutionizes the domain of electronic particle detectors.
First important discoveries from the experiments at the ISR show that protons grow in size as their energy is increased; and particles emerging at wide angles reveal scattering between the constituent particles deep inside the protons.
Georges Charpak of CERN is awarded the Nobel Prize for Physics for his invention of the multiwire proportional chamber.
library.cern.ch /archives/chrono/chrono_2002_cern.php   (2487 words)

  
 Time projection chamber - Wikipedia, the free encyclopedia
In physics, a time projection chamber is a particle detector consisting of a gas-filled cylindrical chamber with multiwire proportional chambers (MWPC) as endplates.
Along its length, the chamber is divided into halves by means of a central high voltage electrode disc, which establishes an electric field between the center and the endplates.
This is done using the usual technique of a drift chamber.
en.wikipedia.org /wiki/Time_projection_chamber   (241 words)

  
 Amazon.com: "multiwire proportional chamber": Key Phrase page   (Site not responding. Last check: 2007-10-10)
INTRODUCTION The first multiwire proportional chamber, in its modern conception, was constructed and operated by Charpak and his collaborators in the years 1967-68 ').
that became the standards of high energy physics for the next several decades: the multiwire proportional chamber and the drift chamber.
This was taken further by Georges Charpak, also at CERN, who invented the multiwire proportional chamber, a detector capable of extremely rapid operation and high resolution.
www.amazon.com /phrase/multiwire-proportional-chamber   (561 words)

  
 Multiwire Laboratories: MWL110 Real-Time Laue Camera   (Site not responding. Last check: 2007-10-10)
On the right side is the proportional counter that makes the images and before it is a motorized three-axis rotation placed on top of the jack and translation stage.
A gas cylinder supplying 90% Argon and 10% CO to the proportional chamber detector is located behind the computer.
The detector is equipped with a selection of four interchangeable collimators (0.5, 1.0, 2.0, and 3.0 mm), a fail-safe x-ray shutter, and a gas delivery system consisting of a Matheson gas regulator with CGA580 inlet (for 90% Argon, 10% CO2 gas mixture).
www.multiwire.com /MWL110.html   (1773 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.