ND Experiment
Encyclopedia
Neutral Detector is a detector for particle physics
experiments
created by the team of physicists in the
Budker Institute of Nuclear Physics
(BINP), Novosibirsk
, Russia
.
Experiments with the ND were conducted from 1982 to 1987 at the e+e− storage ring
VEPP-2M in the energy
range 2E=0.5-1.4 GeV.
of the electron
-positron
annihilation
in the final states with charged particles
were measured in the energy range 2E=0.5-1.4 GeV. Processes with the neutral particles
in the final state were less studied. To investigate the radiative decays
of the
, 
, and 
mesons
and other processes involving photons
,
, and 
mesons
the ND
was constructed. Its distinguishing features are defined by the specially designed electromagnetic calorimeter
based on NaI
(Tl) scintillation counters
.
List of published analyses
Based on goals of the physics program the ND consist of
Electromagnetic calorimeter
Charged particle coordinate system
Flat (shower) coordinate 2-d wire proportional chambers
Iron absorber & anti-coincidence counters
collected with the ND experiment corresponds to the integrated luminosity
19 pb−1.
Results of the experiments with ND are presented in Ref.,
and are included in the PDG
Review.
Particle physics
Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...
experiments
Experiment
An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...
created by the team of physicists in the
Budker Institute of Nuclear Physics
Budker Institute of Nuclear Physics
The Budker Institute of Nuclear Physics is one of the major centres of advanced study of nuclear physics in Russia. It is located in the Siberian town Akademgorodok, on Academician Lavrentiev Avenue. The institute was founded by Gersh Itskovich Budker in 1959...
(BINP), Novosibirsk
Novosibirsk
Novosibirsk is the third-largest city in Russia, after Moscow and Saint Petersburg, and the largest city of Siberia, with a population of 1,473,737 . It is the administrative center of Novosibirsk Oblast as well as of the Siberian Federal District...
, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
.
Experiments with the ND were conducted from 1982 to 1987 at the e+e− storage ring
Storage ring
A storage ring is a type of circular particle accelerator in which a continuous or pulsed particle beam may be kept circulating for a long period of time, up to many hours. Storage of a particular particle depends upon the mass, energy and usually charge of the particle being stored...
VEPP-2M in the energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...
range 2E=0.5-1.4 GeV.
Physics
At the beginning of 80s the leading cross sectionsScattering cross-section
The scattering cross-section, σscat, is a hypothetical area which describes the likelihood of light being scattered by a particle. In general, the scattering cross-section is different from the geometrical cross-section of a particle, and it depends upon the wavelength of light and the...
of the electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
-positron
Positron
The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric charge of +1e, a spin of ½, and has the same mass as an electron...
annihilation
Annihilation
Annihilation is defined as "total destruction" or "complete obliteration" of an object; having its root in the Latin nihil . A literal translation is "to make into nothing"....
in the final states with charged particles
Charged particle
In physics, a charged particle is a particle with an electric charge. It may be either a subatomic particle or an ion. A collection of charged particles, or even a gas containing a proportion of charged particles, is called a plasma, which is called the fourth state of matter because its...
were measured in the energy range 2E=0.5-1.4 GeV. Processes with the neutral particles
Neutral particle
In physics, a neutral particle is a particle with no electric charge. This is not to be confused with a real neutral particle, a neutral particle that is also identical to its own antiparticle.-Stable or long-lived neutral particles:...
in the final state were less studied. To investigate the radiative decays
Particle decay
Particle decay is the spontaneous process of one elementary particle transforming into other elementary particles. During this process, an elementary particle becomes a different particle with less mass and an intermediate particle such as W boson in muon decay. The intermediate particle then...
of the
, , and mesonsMeson
In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...
and other processes involving photons
Photon
In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...
,
, and mesonsMeson
In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...
the ND
was constructed. Its distinguishing features are defined by the specially designed electromagnetic calorimeter
Calorimeter (particle physics)
In particle physics, a calorimeter is an experimental apparatus that measures the energy of particles. Most particles enter the calorimeter and initiate a particle shower and the particles' energy is deposited in the calorimeter, collected, and measured. The energy may be measured in its...
based on NaI
Nai
Nai may refer to:*Nai , a Barber caste in India* Nai language, a language of Papua New Guinea* Nai , an album by singer Anna Vissi*Nai , a wind instrument, also known as the Moldavian pan flute...
(Tl) scintillation counters
Scintillation counter
A scintillation counter measures ionizing radiation. The sensor, called a scintillator, consists of a transparent crystal, usually phosphor, plastic , or organic liquid that fluoresces when struck by ionizing radiation. A sensitive photomultiplier tube measures the light from the crystal...
.
List of published analyses
- Radiative decaysParticle decayParticle decay is the spontaneous process of one elementary particle transforming into other elementary particles. During this process, an elementary particle becomes a different particle with less mass and an intermediate particle such as W boson in muon decay. The intermediate particle then...
- Rare decays of the
, 
, and 
mesons
- Search for rare decays
-
-
-
- light scalars
and 
in 
-meson radiative decays
- Non-resonantResonance (particle physics)In particle physics, a resonance is the peak located around a certain energy found in differential cross sections of scattering experiments. These peaks are associated with subatomic particles and their excitations...
electron-positron annihilationAnnihilationAnnihilation is defined as "total destruction" or "complete obliteration" of an object; having its root in the Latin nihil . A literal translation is "to make into nothing"....
into hadronsHadronIn particle physics, a hadron is a composite particle made of quarks held together by the strong force...
- Test of QEDQEDQED may refer to:*Q.E.D., from the Latin quod erat demonstrandum, used at the end of a definitive proof*Quantum electrodynamics, a field of physics...
processes
-
-
-
-
(virtual Compton scattering)
- Analyses of other processes
- Measurement of the ω-meson parameters
- Upper limits on electron widthResonance (particle physics)In particle physics, a resonance is the peak located around a certain energy found in differential cross sections of scattering experiments. These peaks are associated with subatomic particles and their excitations...
of scalarScalar mesonIn high energy physics, a scalar meson is a meson with total spin 0 and even parity . Compare to pseudoscalar meson....
and tensorTensorTensors are geometric objects that describe linear relations between vectors, scalars, and other tensors. Elementary examples include the dot product, the cross product, and linear maps. Vectors and scalars themselves are also tensors. A tensor can be represented as a multi-dimensional array of...
mesons
, 
, 
, 
, and 
- Search for
Detector
Based on goals of the physics program the ND consist of
Electromagnetic calorimeter
- 168 rectangular NaINaiNai may refer to:*Nai , a Barber caste in India* Nai language, a language of Papua New Guinea* Nai , an album by singer Anna Vissi*Nai , a wind instrument, also known as the Moldavian pan flute...
(Tl) scintillation counters - total mass of NaINaiNai may refer to:*Nai , a Barber caste in India* Nai language, a language of Papua New Guinea* Nai , an album by singer Anna Vissi*Nai , a wind instrument, also known as the Moldavian pan flute...
(Tl) is 2.6 t - solid angle coverage is 65% of 4π sr
- minimum thickness is 32 cm or 12 radiation length
- energy resolution for photons is σ/E = 4% / √E
Charged particle coordinate system
- 3 layers of coaxial cylindrical 2-d wire proportional chambersWire chamberA multi-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 the center of the detector - solid angle coverage is 80% of 4π sr
- angular resolution is 0.5° in the azimuthal and 1.5° in the polar direction
- surrounded by the 5-mm thick plastic scintillation counter for trigger
Flat (shower) coordinate 2-d wire proportional chambers
- 2 layers of flat 2-d wire proportional chambers.
- angular resolution is 2° in the azimuthal and 3.5° in the polar direction for 0.5 GeV photons
Iron absorber & anti-coincidence counters
- The electromagnetic calorimeter is covered by the 10-cm thick iron absorber and plastic scintillation anti-coincidence counters.
Results
DataData
The term data refers to qualitative or quantitative attributes of a variable or set of variables. Data are typically the results of measurements and can be the basis of graphs, images, or observations of a set of variables. Data are often viewed as the lowest level of abstraction from which...
collected with the ND experiment corresponds to the integrated luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...
19 pb−1.
Results of the experiments with ND are presented in Ref.,
and are included in the PDG
Particle Data Group
The Particle Data Group is an international collaboration of particle physicists that compiles and reanalyzes published results related to the properties of particles and fundamental interactions. It also publishes reviews of theoretical results that are phenomenologically relevant, including...
Review.
See also
- Particle detectorParticle detectorIn 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 high-energy particles, such as those produced by nuclear decay, cosmic radiation, or reactions in a...
- Experimental physicsExperimental physicsWithin the field of physics, experimental physics is the category of disciplines and sub-disciplines concerned with the observation of physical phenomena in order to gather data about the universe...
- List of accelerators in particle physics
- Storage ringStorage ringA storage ring is a type of circular particle accelerator in which a continuous or pulsed particle beam may be kept circulating for a long period of time, up to many hours. Storage of a particular particle depends upon the mass, energy and usually charge of the particle being stored...
- Budker Institute of Nuclear PhysicsBudker Institute of Nuclear PhysicsThe Budker Institute of Nuclear Physics is one of the major centres of advanced study of nuclear physics in Russia. It is located in the Siberian town Akademgorodok, on Academician Lavrentiev Avenue. The institute was founded by Gersh Itskovich Budker in 1959...
- MesonMesonIn particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...
- List of particles
- AnnihilationAnnihilationAnnihilation is defined as "total destruction" or "complete obliteration" of an object; having its root in the Latin nihil . A literal translation is "to make into nothing"....