Anomalon is also the type genus of the ichneumon-wasp subfamily Anomaloninae

Anomaloninae

Anomaloninae is a worldwide subfamily of the parasitic wasp family Ichneumonidae.They are koinobiont endoparasitoids of Lepidoptera or Coleoptera. Anomaloninae have a slender abdomen and reticulated propodeum and are found in dry habitats. There are 38 genera.-References:*Gauld, I.D. : The...

.

In physics

Physics

Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

, an anomalon is a hypothetical type of nuclear matter

Nuclear matter

Nuclear matter is an idealized system of interacting nucleons that exists in several phases that as yet are not fully established...

 that shows an anomalously large reactive cross section

Cross section (physics)

A cross section is the effective area which governs the probability of some scattering or absorption event. Together with particle density and path length, it can be used to predict the total scattering probability via the Beer-Lambert law....

. They were first noticed in experimental runs in the early 1980s as short tracks in film emulsions or plastic leaf detectors connected to medium-energy particle accelerator

Particle accelerator

A particle accelerator is a device that uses electromagnetic fields to propel charged particles to high speeds and to contain them in well-defined beams. An ordinary CRT television set is a simple form of accelerator. There are two basic types: electrostatic and oscillating field accelerators.In...

s. The direction of the tracks demonstrated that they were the results of reactions taking place within the accelerator targets, but they stopped so quickly in the detectors that no obvious explanation for their behavior could be offered. A flurry of theoretical explanations followed, but over time a series of follow-up experiments failed to find strong evidence for the anomalons, and active study of the topic largely ended by the late 1980s.

Description

Early particle accelerator

Particle accelerator

A particle accelerator is a device that uses electromagnetic fields to propel charged particles to high speeds and to contain them in well-defined beams. An ordinary CRT television set is a simple form of accelerator. There are two basic types: electrostatic and oscillating field accelerators.In...

s generally consisted of three parts, the accelerator, a metal target, and some sort of detector. Detectors differed depending on the reactions being studied, but one class of inexpensive and useful detectors consisted of a large volume of photographic emulsion, often on individual plates, that would capture the particles as they moved through the stack. As the high-energy community moved to larger accelerators and exotic particle

Exotic particle

An exotic particle is a kind of theoretical particle said to exist by some areas of modern physics, and whose alleged properties are extremely unusual.The best-known example is probably the tachyon, a theoretical particle that always travels faster than light....

s and reactions, new detectors were introduced that worked on different principles. The film technique remains in use today in certain fields; small versions can be flown on balloons, while larger versions can be placed in mines, both in order to capture rare but extremely high-energy cosmic ray

Cosmic ray

Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...

s.

By the late 1970s and early 1980s a generation of accelerators had been made obsolete by newer machines in terms of being useful for leading edge research. Still useful for other tasks, these older machines were turned to a wide variety of new studies. One particularly active area of research is collisions between higher mass particles, instead of fundamental particles

Elementary particle

In particle physics, an elementary particle or fundamental particle is a particle not known to have substructure; that is, it is not known to be made up of smaller particles. If an elementary particle truly has no substructure, then it is one of the basic building blocks of the universe from which...

 like 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...

s or proton

Proton

The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....

s. Although the total energy of the reaction is the same, or lower, than it would be using lighter elementary particles, using heavier elements increases the number of products from the reactions, revealing low-frequency reactions that might otherwise go unnoticed. Noble gas

Noble gas

The noble gases are a group of chemical elements with very similar properties: under standard conditions, they are all odorless, colorless, monatomic gases, with very low chemical reactivity...

ses are particularly useful for these experiments because they are easy to handle, unreactive and relatively inexpensive.

One such experiment was being carried out on the Bevalac at the Lawrence Berkeley National Laboratory

Lawrence Berkeley National Laboratory

The Lawrence Berkeley National Laboratory , is a U.S. Department of Energy national laboratory conducting unclassified scientific research. It is located on the grounds of the University of California, Berkeley, in the Berkeley Hills above the central campus...

 using Argon 40 accelerated to 1.8 GeV and then smashed into a copper target backed with a nuclear emulsion detector. It was here that the anomalons were first observed. While studying the results of these experiments, a number of very short tracks were discovered, penetrating only a short distance into the emulsion. The vast majority of the particles continued into the emulsion over much greater distances, in keeping with expectations and the results of all previous experiments on the machine. The tracks did not appear to be from outside sources like cosmic ray

Cosmic ray

Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...

s. Further studies were carried out with Oxygen 16 and Iron 56, and these experiments also showed the same short tracks.

In order for the particles to stop so quickly within the emulsion, they would either have to have low energies, and thus be moving slowly, be extremely massive, and thus have high energy but still move slowly, or they were reacting with the emulsion itself and turning into other particles. The first possibility, that they were low-energy particles, did not seem likely given the physics of the accelerator. The second, that they were high mass, was contradicted by other measurements that suggested the particles had a charge of 14, like silicon

Silicon

Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...

, and would thus be very likely have a low mass. This left only the third possibility, that they were reacting with the emulsion itself. This was by no means uncommon, these reactions were used as an integral part of the detection process, but it was the speed that these reactions would have to take place that was odd. In order to produce such short tracks, the particles would have to be reacting much more quickly than ever seen before. The particles became known as "anomalons" due to their apparently anomalous reaction rates. If they were following the same basic rules as other matter, and interacting with the emulsion due to the strong force, their component of the strong force was about ten times the strength of known reactions.

A series of experiments followed, attempting to duplicate the results. Many of these used an alternate detector system using thin sheets of plastic, and these failed to turn up any evidence of the anomalons. It was suggested that this was due to the cross section of the reaction, whatever it was, being much higher in higher-mass nuclei, which was the case for the emulsion detectors but not the plastic. Others suggested they were actually seeing quark-gluon soups for the first time. A workshop on the issue was held at LBNL in 1984.

However, as study continued the number of negative results continued to grow. By 1987 interest in the topic had waned, and most research in the field ended. However, some research continued and in 1998 Piyare Jain

Piyare Jain

Professor Emeritus Piyare L. Jain is a particle physicist at University of Buffalo. On December 6, 2006, he claimed discovery of the long-sought axion subatomic particle....

 claimed to have finally demonstrated them conclusively, using larger accelerators at Brookhaven National Laboratory

Brookhaven National Laboratory

Brookhaven National Laboratory , is a United States national laboratory located in Upton, New York on Long Island, and was formally established in 1947 at the site of Camp Upton, a former U.S. Army base...

 and CERN

CERN

The European Organization for Nuclear Research , known as CERN , is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border...

 and combining that with a thin detector which he claimed was key to the problem of detecting the anomalons. More recently he has claimed that the particles in question are actually the elusive axion

Axion

The axion is a hypothetical elementary particle postulated by the Peccei-Quinn theory in 1977 to resolve the strong CP problem in quantum chromodynamics...

, long thought to be part of the standard model

Standard Model

The Standard Model of particle physics is a theory concerning the electromagnetic, weak, and strong nuclear interactions, which mediate the dynamics of the known subatomic particles. Developed throughout the mid to late 20th century, the current formulation was finalized in the mid 1970s upon...

, but unseen in spite of decades of searching.