Down quark

The spectrum in the 2SC state is made of 5 massive Gluons with a mass of the order of the gap, 3 massless Gluons confined (at zero temperature) into light glueballs and gapless up and down quarks in the direction (say) 3 of color. 

To describe such pairing, we consider small fluctuations of up and strange quarks near p. The energy of such fluctuations of up and down quarks is respectively... 

Most interactions favor a condensation in the scalar color antitriplet channel. There are two different condensation patterns in this channel, depending on whether or not the strange quarks, which are more massive than the light up and down quarks, participate in forming a condensate,... 

Our example deals with quarks of the third color in a phase composed only of up and down quarks. As only quarks of a single color are involved, the pairing must take place in a channel which is symmetric in color. Assuming s-wave condensation in an isospin-singlet channel, a possible candidate is a spin-1 condensate [8], We consider the condensate... 

Here To = y 11/ is proportional to the unit matrix in flavor space. The quark field ip now contains a third component in flavor space, the strange quark, and consequently the mass matrix rh, see Eq. (4), is equally enlarged by the current strange quark mass, ms, which can in general be different from up and down quark masses. This interaction consists of a U(3)l x U(3)ft-syrnmetric 4-point interaction and a 7 Hooft-type 6-point interaction which breaks the UA (1) symmetry. 

Qualitatively, the existence of these phases is quite plausible At low values ot jJLq the Fermi momenta of the up and down quarks are relatively similar to each other, whereas the strange quarks are suppressed because of their larger mass. With increasing negative fiQ, however, the up quarks become more and more disfavored and eventually the Fermi momenta are ordered as p f < <... 

Abstract The ground state of dense up and down quark matter under local and global charge neutrality conditions with / -equilibrium has at least four possibilities normal, regular 2SC, gapless 2SC phases, and mixed phase composed of 2SC phase and normal components. The discussion is focused on the unusual properties of gapless 2SC phase at zero as well as at finite temperature. 

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. 

Was this youT answer According to the periodic table, the nucleus of a helium atom consists of 2 protons and 2 neutrons. This adds up to six up quarks plus six down quarks foT a total of 12 quarks. 

Number of Particle Families. How many families of matter may exist Three, four, or more An acceptable number among researchers today is three, Three family entities make up matter—the stars, the planets, molecules, and the atoms in the paper upon which this is printed. These fundamental particles are the up1 quark, the down quark, and the electron,. Some other researchers are not quite so confident. One is reminded of the quotation from Jonathan Swift ... 

QUARKS. Quarks are fundamental marter particles that are constituents of neutrons and protons and other hadrons. There are six different types of quarks, (physicists call them flavors ), each of which have a unique mass. The two lightest, unimaginatively called up and down quarks, combine to form protons and neutrons. The heavier quarks aren t found in nature and have so far only been observed in particle accelerators. No one has ever seen a quark. Yet physicists seem to know quite a lot about the properties and behavior of these ubiquitous elementary particles. 

Quarks were first identified by observing the products formed in high-energy nuclear collisions. Six types of quarks are recognized. Each quark type is known as a flavor. The six flavors are up, down, top, bottom, strange, and charm. Only two of these—the up and down quarks—compose protons and neutrons. A proton is made up of two up quarks and one down quark, while a neutron consists of one up quark and two down quarks. The other four types of quarks exist only in unstable particles that spontaneously break down during a fraction of a second. 

Protons and neutrons each contain three quarks. A neutron consists of one up quark and two down quarks. A... 

Protons and neutrons each contain three quarks. A neutron consists of one up quark and two down quarks. A proton consists of two up quarks and one down quark. Other quarks are named strange, charm, bottom, and top., but these four are not part of atoms. Quarks are a fundamental constituent of matter according to current standard model of particle physics, but individual quarks are not seen. Instead they are always confined within other subatomic particles. There is no need to consider quarks when describing chemical interactions. Only electrons are involved in chemical reactions. The position and sizes of these particles in a helium atom is indicated in the diagram at right. A diagram... 

Here Z is the number of protons, N the number of neutrons, and CiuA the vector part of the Z-quark vertex for the up and down quarks. Putting in the tree level values of C u and Cu gives... 

Quarks are not found individually, but are found with other quarks arranged to form composites known as hadrons. There are two basic types of hadrons baryons, composed of three quarks, and mesons, composed of a quark and an anti-quark. Examples of baryons are the neutron and the proton. Neutrons are made of two down quarks and one up quark. Protons are made of two up quarks and one down quark. An example of the meson is the pion. This particle is made of an up quark and a down anti-quark. Such particles are unstable and tend to decay rapidly. The anti-particle of the proton is the anti-proton. The exception to the rule is the electron, whose anti-particle is the positron. 

The six quarks, namely the up quark (u), the down quark (d), the strange quark (s), the charm quark (c), the top quark (t), sometimes also called truth quark, and the bottom quark (b), also dubbed beauty quark, carry a colour charge. The bosons that act on colour, are called gluons, which are the carriers of the colour interaction. The residue of this interaction is the strong nuclear interaction, which is operative between the hadrons (for instance the proton and the neutron within an atomic nucleus). 

What remains is the inclusions of hadrons in the model. In analogy to the leptons, left-handed SU 2) doublets and right-handed SU 2) singlets are build from the quarks of each family, which are initially assumed to be massless. For the first family with the up quark u and the down quark d we have for instance ... 

The meaning of the prime for the down quark will be discussed shortly. Analogously to the leptons, the following Lagrange density Cg for the quarks is added to the full model Lagrange density ... 

Y is again the weak hypercharge Y = 2 q — tz), which is 1/3 for u and d, 4/3 for Uij and —2/3 for dij. This ensures that the correct electric charges for the coupling of the up quark (+(2/3)e) and the down quark (—(l/3)e) to the field is obtained. The Yukawa term >CYuk.,g( ), which assigns masses to the quarks upon symmetry breaking, differs from that for the leptons, since both the up and the down quark carry masses ... 

Note, that in the Yukawa term only the unprimed down quarks appear. Here (a ) is the charge conjugate of the Higgs field (x) ... 

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