Protons quarks

Electrorefining purification of a metal using electrolysis Electrostatic charge at rest Element see Chemical Element Elementary Particle collectively the smallest units of matter, electrons, protons, quarks, and so on. 

J. I. Friedman and H. W. Kendall (Massachusetts Institute of Technology) and R. E. Taylor (Stanford) pioneering investigations concerning deep elastic scattering of electrons on protons and bound neutrons, of essential importance for the development of the quark model in particle physics. 

As far as is known, ordinary matter is made of tiny building blocks called elementary particles. For example, an atom is made up of a nucleus surrounded by one or more electrons. As far as scientists have been able to determine, the electrons are elementary particles, not made of anything simpler. Fdowever, an atomic nucleus is not clcmcntai y, but is a composite particle made up of simpler particles called protons and neutrons. (The lightest nucleus is the nucleus of ordinai y hydrogen, which consists of only a single proton.) Today, physicists believe that even protons and neutrons are not elementai y but are composite particles made up of still simpler building blocks called quarks. 

At the present time, quarks are believed to be elementary particles. All the particles in an atom, whether elementary or not, are particles of matter and possess mass. Electrons, protons, and neutrons can also exist outside of atoms. 

Xn an entiraly different wetter. X have been reading and thinking about the proton and quarks. The 9en r l wey how Nobel Prises have been given seems to be far from proper, but 1 obviously hava no influence. The second point is that the whole discussion of quarks and gluons is a little unconvincing. I hava even triad soma improvement on the way to look at the problem. I hava nothing really to report, but t continue to worry. 

The commonly accepted pulsar model is a neutron star of about one solar mass and a radius of the order of ten kilometers. A neutron star consists of a crust, which is about 1 km thick, and a high-density core. In the crust free neutrons and electrons coexist with a lattice of nuclei. The star s core consists mainly of neutrons and a few percents of protons and electrons. The central part of the core may contain some exotic states of matter, such as quark matter or a pion condensate. Inner parts of a neutron star cool up to temperatures 108iT in a few days after the star is formed. These temperatures are less than the critical temperatures Tc for the superfluid phase transitions of neutrons and protons. Thus, the neutrons in the star s crust and the core from a superfluid, while the protons in the core form a superconductor. The rotation of a neutron superfluid is achieved by means of an array of quantized vortices, each carrying a quantum of vorticity... 

In the simplest approximation we consider an ideal quantum gas of elementary particles such as protons, neutrons, electrons and possibly neutrinos (the quark-gluon substructure will not be considered at densities and temperatures considered). The EOS is found in textbooks and will not be discussed any further here. 

R possesses a spherical core of radius a consisting of quark matter with CFL condensate surrounded by a spherical shell of hadronic matter with thickness R — a containing neutron and proton superfluids. The triangular lattice of singly quantized neutron vortices with quantum of circulation irh/jj, forms in response to the rotation. Since the quark vortices carry SttTj/fi quantum of circulation, the three singly quantized neutron vortices connect at the spherical interface with one singly quantized quark vortex so that the baryon chemical potential is continuous across the interface [19]. 

The entrainment of superfluid protons by rotating superfluid neutrons leads to appearance of proton vortices and to generation of a homogeneous mean magnetic field with amplitude B and direction parallel to the axis of rotation of the star [20], This field will penetrate into the quark core through the normal cores of quark vortices. 

The effect of thermal pion fluctuations on the specific heat and the neutrino emissivity of neutron stars was discussed in [27, 28] together with other in-medium effects, see also reviews [29, 30], Neutron pair breaking and formation (PBF) neutrino process on the neutral current was studied in [31, 32] for the hadron matter. Also ref. [32] added the proton PBF process in the hadron matter and correlation processes, and ref. [33] included quark PBF processes in quark matter. PBF processes were studied by two different methods with the help of Bogolubov transformation for the fermion wave function [31, 33] and within Schwinger-Kadanoff-Baym-Keldysh formalism for nonequilibrium normal and anomalous fermion Green functions [32, 28, 29],... 

It may be worthwhile to compare with the book (21) about protons in chemistry. The writer suspects that positive quarks (held in the outer valence regions by the repulsion from the positive nuclei) are attracted to what we loosely may call chemically polarizable materials (22) having readily deformable electron densities. 

As far goes mobility of positive quarks (spontaneous in Nature, or laboratory methods of pre-concentration) it may be worthwhile to compare with a recent review (32) of the mobility and injection of protons in (mainly non-metallic) solids. Recently, Jones (59, 60) carefully reviewed the experimental evidence for and against the existence of quarks. 

If an a-particle (4He nucleus) adds a d-quark, the energy difference should be almost 4 times the case of a proton. The first electron is bound (5/3)2 rydberg or 38 eV. The binding of the second electron can be extrapolated from the parabolic variation (20) in the isoelectronic series He, Li+, Be+2,... to be 13 eV, comparable with oxygen and chlorine atoms. Hence, the species He(d)-1/3 is not particularly reactive, though its proton adduct He(d)H+2/3 should be far less acidic than HeH+ (which is already stable toward dissociation in the gaseous state, but too strong a Br nsted acid to persist in any known solvent). 

Both protons and antiprotons are made of quarks. When their quarks collide, there is evidence of smaller particles. Quarks are hypothetical entities that carry very small electrical charges. They are considered the major constituents of the smallest bits of matter. Both quarks and leptons (several lighter atomic elementary particles) are the basic building blocks of mat-... 

The experiments went on, however, and in 1968 experiments at the Stanford Linear Accelerator Laboratory showed that quarks were indeed real. When protons were bombarded with high-energy electrons, pointlike charges were discovered inside the proton. These charges could only be charged particles, in other words, quarks. 

There were still problems, however. Physicists had never succeeded in gaining a good theoretical understanding of the so-called strong force, the force that held protons and neutrons together in nuclei. They had devised various approximations that described this force but none was entirely accurate. It was now apparent why they had failed. The strong force was actually the result of forces between quarks inside protons and neutrons. No one yet knew what these forces were, but there was every reason to think that their nature would sooner or later be discovered. 

Quarks carry a fractional charge of Vj or Fy Six flavors or types of quarks make up all subatomic particles. Each flavor of quark can be fiufher classified as having one of three colors. These are not colors or flavors as commonly thought of, but part of a classification scheme used to explain how matter behaves. The language of quarks makes them seem like some creation of fantasy, but the quark theory can be used to explain many properties of subatomic particles. For example, a proton can be considered to be made of two up quarks and a down quark, and a neutron of two down quarks and an up quark (Figure 4.8). Quark flavors and charges are given in Table 4.5. 

Is the neutron as we understand it today really a combination of a proton and electron as Rutherford envisioned it This is a philosophically interesting question. When neutrons decay, they produce a proton and an electron (and an antineutrino as well) however, these particles are not understood to have a real existence within an intact neutron. Indeed, the constituent parts of neutrons (and protons for that matter) are understood to be quarks. The phenomenon of neutron decay is explained by a transformation of one of its constituent quarks, turning the neutron into a proton the energy difference between the neutron and proton gives rise to the electron and antineutrino. 

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