The Cherenkov light is following a zigzag path between parallel surfaces. The light detectors would be positioned to the right.
A charged particle travelling through a material (for instance fused silica) with a speed greater than c/n (n refractive index, c vacuum speed of light) emits Cherenkov radiation. If the light angle on the surface is sufficiently shallow, this radiation is contained inside and transmitted through internal reflections to an expansion volume, coupled to photomultipliers (or other types of photon detectors), to measure the angle. Preserving the angle requires a precise planar and rectangular cross section of the radiator. Knowledge of the angle at which the radiation was produced, combined with the track angle and the particle's momentum (measured in a tracking detector like a drift chamber) may be used to calculate the particle's mass.
A DIRC was first proposed by Blair Ratcliff as a tool for particle identification at a B-Factory, and the design was first used by the BaBar collaboration at SLAC. Since the successful operation in the BaBar experiment next-generation DIRC-type detectors have been designed for several new particle physics experiments, including Belle-II, PANDA, and GlueX. The DIRC differs from earlier RICH and CRID Cherenkov light detectors in that the quartz bars used as radiators also transmit the light.
C Lu; D Marlow; C Mindas (1996). "Detection of internally reflected Cherenkov light, results from the BELLE DIRC prototype". Proceedings of the Second International Workshop on Ring Imaging Cherenkov Detectors. 371 (1–2): 82–86. Bibcode:1996NIMPA.371...82L. doi:10.1016/0168-9002(95)01256-7.
P. Coyle; H. Kawahara; A. Lu (1994). "The DIRC counter: a new type of particle identification device for B factories". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 343 (1): 292–299. Bibcode:1994NIMPA.343..292C. CiteSeerX10.1.1.382.2452. doi:10.1016/0168-9002(94)90568-1.
A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate. Sometimes, the excited state is metastable, so the relaxation back down from the excited state to lower states is delayed. The process then corresponds to one of two phenomena: delayed fluorescence or phosphorescence. The correspondence depends on the type of transition and hence the wavelength of the emitted optical photon.
The BaBar experiment, or simply BaBar, is an international collaboration of more than 500 physicists and engineers studying the subatomic world at energies of approximately ten times the rest mass of a proton (~10 GeV). Its design was motivated by the investigation of charge-parity violation. BaBar is located at the SLAC National Accelerator Laboratory, which is operated by Stanford University for the Department of Energy in California.
In experimental and applied particle physics, nuclear physics, and nuclear engineering, a particle detector, also known as a radiation detector, is a device used to detect, track, and/or identify ionizing particles, such as those produced by nuclear decay, cosmic radiation, or reactions in a particle accelerator. Detectors can measure the particle energy and other attributes such as momentum, spin, charge, particle type, in addition to merely registering the presence of the particle.
A wire chamber or multi-wire proportional chamber is a type of proportional counter that detects charged particles and photons and can give positional information on their trajectory, by tracking the trails of gaseous ionization.
A Cherenkov detector is a particle detector using the speed threshold for light production, the speed-dependent light output or the speed-dependent light direction of Cherenkov radiation.
Photodetectors, also called photosensors, are sensors of light or other electromagnetic radiation. There are a wide variety of photodetectors which may be classified by mechanism of detection, such as photoelectric or photochemical effects, or by various performance metrics, such as spectral response. Semiconductor-based photodetectors typically use a p–n junction that converts photons into charge. The absorbed photons make electron–hole pairs in the depletion region. Photodiodes and photo transistors are a few examples of photo detectors. Solar cells convert some of the light energy absorbed into electrical energy.
The ring-imaging Cherenkov, or RICH, detector is a device for identifying the type of an electrically charged subatomic particle of known momentum, that traverses a transparent refractive medium, by measurement of the presence and characteristics of the Cherenkov radiation emitted during that traversal. RICH detectors were first developed in the 1980s and are used in high energy elementary particle-, nuclear- and astro-physics experiments.
In physics, a time projection chamber (TPC) is a type of particle detector that uses a combination of electric fields and magnetic fields together with a sensitive volume of gas or liquid to perform a three-dimensional reconstruction of a particle trajectory or interaction.
HEGRA, which stands for High-Energy-Gamma-Ray Astronomy, was an atmospheric Cherenkov telescope for Gamma-ray astronomy. With its various types of detectors, HEGRA took data between 1987 and 2002, at which point it was dismantled in order to build its successor, MAGIC, at the same site.
DELPHI was one of the four main detectors of the Large Electron–Positron Collider (LEP) at CERN, one of the largest particle accelerators ever made. Like the other three detectors, it recorded and analyzed the result of the collision between LEP's colliding particle beams. The specific focus of DELPHI was on particle identification, three-dimensional information, high granularity (detail), and precise vertex determination.
Thomas John Ypsilantis was an American physicist of Greek descent. Ypsilantis was known for the co-discovery of the antiproton in 1955, along with Owen Chamberlain, Emilio Segrè, and Clyde Wiegand. Following this work, he moved to CERN to develop Cherenkov radiation detectors for use in particle physics.
Neutron detection is the effective detection of neutrons entering a well-positioned detector. There are two key aspects to effective neutron detection: hardware and software. Detection hardware refers to the kind of neutron detector used and to the electronics used in the detection setup. Further, the hardware setup also defines key experimental parameters, such as source-detector distance, solid angle and detector shielding. Detection software consists of analysis tools that perform tasks such as graphical analysis to measure the number and energies of neutrons striking the detector.
A neutrino detector is a physics apparatus which is designed to study neutrinos. Because neutrinos only weakly interact with other particles of matter, neutrino detectors must be very large to detect a significant number of neutrinos. Neutrino detectors are often built underground, to isolate the detector from cosmic rays and other background radiation. The field of neutrino astronomy is still very much in its infancy – the only confirmed extraterrestrial sources as of 2018 are the Sun and the supernova 1987A in the nearby Large Magellanic Cloud. Another likely source is the blazar TXS 0506+056 about 3.7 billion light years away. Neutrino observatories will "give astronomers fresh eyes with which to study the universe".
A wavelength shifter is a photofluorescent material that absorbs higher frequency photons and emits lower frequency photons. The material absorbs one photon, and emits one or multiple lower-energy photons. The relaxation time of the excited molecule is usually in the order of nanoseconds.
In particle physics, tracking is the process of reconstructing the trajectory of electrically charged particles in a particle detector known as a tracker. The particles entering such a tracker leave a precise record of their passage through the device, by interaction with suitably constructed components and materials. The presence of a calibrated magnetic field, in all or part of the tracker, allows the local momentum of the charged particle to be directly determined from the reconstructed local curvature of the trajectory for known electric charge of the particle.
ALEPH was a particle detector at the Large Electron-Positron collider (LEP) at CERN. It was designed to explore the physics predicted by the Standard Model and to search for physics beyond it.
Cherenkov radiation is electromagnetic radiation emitted when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium. A classic example of Cherenkov radiation is the characteristic blue glow of an underwater nuclear reactor. Its cause is similar to the cause of a sonic boom, the sharp sound heard when faster-than-sound movement occurs. The phenomenon is named after Soviet physicist Pavel Cherenkov.
The NA62 experiment is a fixed-target particle physics experiment in the North Area of the SPS accelerator at CERN. The experiment was approved in February 2007. Data taking began in 2015, and the experiment is expected to become the first in the world to probe the decays of the charged kaon with probabilities down to 10−12. The experiment's spokesperson is Cristina Lazzeroni. The collaboration involves 333 individuals from 30 institutions and 13 countries around the world.
The AMY detector was used by particle physicists at the TRISTAN electron-positron collider at KEK in Japan between 1984 and 1995 to search for new particles and perform precision studies of the strong and electroweak forces.
Linda Gail Stutte is an experimental elementary particle physicist. After an appointment as a postdoc at Caltech in 1974–76, Stutte was a research staff scientist at the Fermi National Accelerator Laboratory from 1976 through her retirement in 2007. She is known for work on neutrino experiments and her expertise with Fermliab neutrino beam facilities.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
