User:John R. Brews/Coriolis force: Difference between revisions
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All baryons must have all three colors present, ''r, g, ''and'' b'', and so are colorless, and exhibit no external evidence of the strong color interaction. Likewise, regardless of the flavor combinations in a meson, the colors of the quark-antiquark cancel, so the meson also is colorless to the outside world.<ref name=McParland/> The role of the color force is thus simply to hold the quark combinations together, which is accomplished by exchange of gluons among the constituent quarks. | All baryons must have all three colors present, ''r, g, ''and'' b'', and so are colorless, and exhibit no external evidence of the strong color interaction. Likewise, regardless of the flavor combinations in a meson, the colors of the quark-antiquark cancel, so the meson also is colorless to the outside world.<ref name=McParland/> The role of the color force is thus simply to hold the quark combinations together, which is accomplished by exchange of gluons among the constituent quarks. | ||
The quarks | The quarks that may engage one another in reactions are determined by the [[Cabbibo-Kobayashi-Maskawa matrix]]:[http://books.google.com/books?id=f89yg8a1t-EC&pg=PA23&dq=Cabibbo+angle&hl=en&ei=XYZvToTqN7PZiAKM55juBg&sa=X&oi=book_result&ct=result&resnum=2&ved=0CDIQ6AEwATgK#v=onepage&q=Cabibbo%20angle&f=false Morii] | ||
:<math>\begin{pmatrix} | :<math>\begin{pmatrix} | ||
d'\\ | d'\\ | ||
Line 212: | Line 212: | ||
b\\ | b\\ | ||
\end{pmatrix} </math> | \end{pmatrix} </math> | ||
Thus, the up and down quarks are assembled as: | |||
The quarks can be arranged to exhibit right- and left-handedness, subscripts ''L'' and ''R'', to resemble the leptons. The right-handed quarks do not couple to the weak interaction, and are labeled with subscript ''R''. The left-handed quarks corresponding to these right-handed quarks are mixtures of quarks. Thus, the up and down quarks are assembled as: | |||
:<math> \tbinom {u}{d}_L \ ; \ \ u_R,\ d_R \ .</math> | :<math> \tbinom {u}{d}_L \ ; \ \ u_R,\ d_R \ .</math> |
Revision as of 09:38, 14 September 2011
Quarks
Quarks are a type of particle with spin 1/2 that are subject to strong, weak and electromagnetic forces. The known quarks are listed in the table below. The kinds of quark (u, d, c, s, t, d) are referred to as the flavor index of the quark, and besides a flavor index, each quark has a color index, which may be any of three colors: red, green and blue (r, g, b). In a stretched analogy to light, a combination of three quarks with all three colors is referred to as "white" or "colorless" and exhibits no external evidence of a color index. Their antiparticles also are quarks, but carry anti-colors: anti-red, anti-green, anti-blue. A combination of quark and anti-quark with a color and its anti-color is "white" or "colorless".
Unlike a particle's electric charge, which can be any multiple of the elementary charge e, a quark can carry only one unit of color. The elementary unit of color has not been measured, a result of failure to observe an isolated quark.
Name | Symbol | Family/Generation | B | YW | Q(e) | IS3 | C | S | T | B′ | Mass (MeV) | Antiparticle | Antiparticle symbol |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Up | u | 1 | +1/3 | +1/3 | +2/3 | +1/2 | 0 | 0 | 0 | 0 | 2.34 ± 0.19 [3] | Antiup | ū |
Down | d | 1 | +1/3 | +1/3 | −1/3 | −1/2 | 0 | 0 | 0 | 0 | 4.78 ± 0.11 [3] | Antidown | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline d} |
Strange | s | 2 | +1/3 | −2/3 | −1/3 | 0 | 0 | −1 | 0 | 0 | 100.2 ± 2.4[3] | Antistrange | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline s} |
Charm | c | 2 | +1/3 | +4/3 | +2/3 | 0 | +1 | 0 | 0 | 0 | 1.294 ± 0.004 × 103 [3] | Anticharm | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline c} |
Bottom | b | 3 | +1/3 | -2/3 | −1/3 | 0 | 0 | 0 | 0 | −1 | 4.19 (+0.18) (−0.06) × 103 [3] | Antibottom | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline b} |
Top | t | 3 | +1/3 | +4/3 | +2/3 | 0 | 0 | 0 | +1 | 0 | 172.9 ±0.6 ±0.9 × 103 [3] | Antitop | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline t} |
* Notation such as ±xxx denotes measurement uncertainty. In the case of the top quark, the first uncertainty is statistical in nature, and the second is systematic.
The quarks carry fractional electric charge. However, no quark has been observed in isolation, so a "free" fractional electric charge has not been seen.
The quark structure of some strongly interacting sub-atomic particles (some hadrons) is shown in the following tables.[4]
Name | Symbol | Quark structure | Electric charge | Spin |
---|---|---|---|---|
Proton | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle P} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle uud} | +1 | 1/2 |
Antiproton | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline P} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \overline {u}\, \overline {u}\,\overline d} | −1 | 1/2 |
Neutron | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle N} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle udd} | 0 | 1/2 |
Lambda | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Lambda} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle uds} | 0 | 1/2 |
Omega | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Omega^-} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle sss} | −1 | 3/2 |
Name | Symbol | Quark structure | Electric charge | Spin |
---|---|---|---|---|
Pion | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \pi^+} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle u\overline d} | +1 | 0 |
Kaon | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle K^-} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle s \overline {u}} | −1 | 0 |
Rho | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \rho^+} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle u\overline d} | +1 | 1 |
D-plus | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle D^+} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle c \overline d} | +1 | 0 |
Eta-c | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \eta_c} | Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle c \overline c} | 0 | 0 |
All baryons must have all three colors present, r, g, and b, and so are colorless, and exhibit no external evidence of the strong color interaction. Likewise, regardless of the flavor combinations in a meson, the colors of the quark-antiquark cancel, so the meson also is colorless to the outside world.[5] The role of the color force is thus simply to hold the quark combinations together, which is accomplished by exchange of gluons among the constituent quarks.
The quarks that may engage one another in reactions are determined by the Cabbibo-Kobayashi-Maskawa matrix:Morii
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{pmatrix} d'\\ s'\\ b'\\ \end{pmatrix} = \begin{pmatrix} U_{ud}&U_{us}&U_{ub}\\ U_{cd}&U_{cs}&U_{cb}\\ U_{td}&U_{ts}&U_{tb}\\ \end{pmatrix}=\begin{pmatrix} d\\ s\\ b\\ \end{pmatrix} }
The quarks can be arranged to exhibit right- and left-handedness, subscripts L and R, to resemble the leptons. The right-handed quarks do not couple to the weak interaction, and are labeled with subscript R. The left-handed quarks corresponding to these right-handed quarks are mixtures of quarks. Thus, the up and down quarks are assembled as:
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tbinom {u}{d}_L \ ; \ \ u_R,\ d_R \ .}
The other generations are arranged similarly:
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tbinom {c}{s}_L \ ; \ \ c_R,\ s_R \ , }
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tbinom {t}{b}_L \ ; \ \ t_R,\ b_R \ . }
Symbol | Electric charge, Q | Weak isospin, (IW, IW3) | Weak hypercharge, (YW) |
---|---|---|---|
uL, cL, tL | +2/3 | (1/2, +1/2) | +1/3 |
dL, sL, bL | −1/3 | (1/2, −1/2) | +1/3 |
uR, cR, tR | +2/3 | 0 | +4/3 |
dR, sR, bR | −1/3 | 0 | −2/3 |
- ↑ Cite error: Invalid
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- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Cite error: Invalid
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