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kdungs committed Dec 12, 2014
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48 changes: 27 additions & 21 deletions html/CPV.html
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<p class="lead">You discovered CP violation!</p>

<h4>CP Symmetry</h4>
<p data-min-level="1">C (Charge) and P (Parity) are discrete transformations that can be applied to a physical system.</p>
<p data-min-level="1">If a theory is symmetric under C, then it works the same if all particles are exchanged with their antiparticles.
If it has P-symmetry, then it is invariant under inversion ("mirroring") of all spatial coordinates</p>
<p data-min-level="5">For a long time, physicists believed that all of physics is invariant under the combination CP of both symmetries.
It turned out that this is wrong, as was discovered by Cronin, Fitch et al. in 1964 when they studied the decay of the neutral K meson.</p>
<section data-min-level="1">
<h4>CP Symmetry</h4>
<p>
C (Charge) and P (Parity) are discrete transformations that can be applied to a physical system.
</p>
<p>
If a theory is symmetric under C, then it works the same if all particles are exchanged with their antiparticles. If it has P-symmetry, then it is invariant under inversion ("mirroring") of all spatial coordinates
</p>
<p data-min-level="5">
For a long time, physicists believed that all of physics is invariant under the combination CP of both symmetries. It turned out that this is wrong, as was discovered by Cronin, Fitch et al. in 1964 when they studied the decay of the neutral K meson.
</p>
</section>

<div class="container">
<section class="container" data-min-level="10">
<div class="row">
<h5>CPV in the Kaon System</h5>
<div class="col-md-3">
<img class="img-responsive" src="assets/info/cpv.png" alt="A plot from the original publication">
</div>
<div class="col-md-3">
<p>In 1964, Cronin, Fitch, et al. showed that CP symmetry is broken in the decay of the long-lived neutral K meson.</p>
<p>If all of physics was invariant under CP transformation, then this long-lived version of the K meson would never decay into two pions.</p>
<p>However, this kind of decay was discovered!</p>
<p>You can see their results on the left: In the middle plot (the one relevant for K-meson decays), a clear excess is recognizable.</p>
<p>For their discovery, Cronin and Fitch received the Nobel Prize in Physics in 1980.</p>
</div>
</div>
<h5>CPV in the Kaon System</h5>
<div class="col-md-3">
<img class="img-responsive" src="assets/info/cpv.png" alt="A plot from the original publication">
</div>
<div class="col-md-3">
<p>In 1964, Cronin, Fitch, et al. showed that CP symmetry is broken in the decay of the long-lived neutral K meson.</p>
<p>If all of physics was invariant under CP transformation, then this long-lived version of the K meson would never decay into two pions.</p>
<p>However, this kind of decay was discovered!</p>
<p>You can see their results on the left: In the middle plot (the one relevant for K-meson decays), a clear excess is recognizable.</p>
<p>For their discovery, Cronin and Fitch received the Nobel Prize in Physics in 1980.</p>
</div>
</section>

<h5><b>Resources</b></h5>
<hr>
<h5>Resources</h5>
<ul>
<li><a href="http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.13.138" target="_blank">The original publication by Cronin, Fitch et al.</a></li>
<li><a href="http://en.wikipedia.org/wiki/CP_violation" target="_blank">Wikipedia on CP violation</a></li>
<li><a href="http://en.wikipedia.org/wiki/Kaon#CP_violation_in_neutral_meson_oscillations" target="_blank">Neutral kaon mixing on Wikipedia</a></li>
</ul>
</div>
27 changes: 18 additions & 9 deletions html/Jpsi.html
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<p class="lead">You discovered the J/ψ meson!</p>
<h5><b>The J/ψ meson</b></h5>
<img class="img-responsive" src="assets/info/jpsi.png" alt="A plot from one of the original publications" align="center">
<p>
The J/ψ is a meson consisting of a charm quark and its antiquark. It is the first excited state of the charmonium (a bound charm-anticharm state), and was discovered independently by two research groups in 1974: one at the Stanford Linear Accelerator Center, led by Burton Richter, and one at the Brookhaven National Laboratory, led by Samuel Ting of MIT. Richter and Ting were awarded the 1976 Nobel Prize in Physics for their shared discovery.
</p>

<h5><b>History of the name</b></h5>
<p>
The J/ψ is the only particle with a two-letter name, as a result of its nearly simultaneous discovery by two independent groups. Ting wanted to name the particle “J”, while Richter called it “SP” (after the SPEAR accelerator used at SLAC), a name none of his colleagues liked. Richter finally settled on the Greek letter “ψ” (pronounced “psi”).<br>Since the scientific community considered it unjust to give one of the two discoverers priority, most subsequent publications have referred to the particle as the “J/ψ”.
</p>
<section data-min-level="1">
<h4>The J/ψ meson</h4>
<img class="img-responsive" src="assets/info/jpsi.png" alt="A plot from one of the original publications" align="center">
<p>
The J/ψ is a meson consisting of a charm quark and its antiquark. It is the first excited state of the charmonium (a bound charm-anticharm state), and was discovered independently by two research groups in 1974: one at the Stanford Linear Accelerator Center, led by Burton Richter, and one at the Brookhaven National Laboratory, led by Samuel Ting of MIT. Richter and Ting were awarded the 1976 Nobel Prize in Physics for their shared discovery.
</p>
</section>

<section data-min-level="5">
<h5>History of the name</h5>
<p>
The J/ψ is the only particle with a two-letter name, as a result of its nearly simultaneous discovery by two independent groups. Ting wanted to name the particle “J”, while Richter called it “SP” (after the SPEAR accelerator used at SLAC), a name none of his colleagues liked. Richter finally settled on the Greek letter “ψ” (pronounced “psi”).
</p>
<p>
Since the scientific community considered it unjust to give one of the two discoverers priority, most subsequent publications have referred to the particle as the “J/ψ”.
</p>
</section>

<hr>
<h5><b>Resources</b></h5>
<ul>
<li><a href="http://prl.aps.org/pdf/PRL/v33/i23/p1404_1" target="_blank">The original presentation of J. J. Aubert et al.</a></li>
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24 changes: 14 additions & 10 deletions html/b.html
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<p class="lead">You discovered the bottom quark!</p>

<h5><b>The bottom (or beauty) quark</b></h5>
<img class="img-responsive" src="assets/info/b.png" alt="A plot from one of the original publications" align="center">
<br>
<p>
The bottom (or beauty) quark is a third-generation quark with a charge of &minus;&frac13;. It has a large mass (around 4.2 GeV/c<sup>2</sup> — more that four times the mass of a proton!). The bottom quark is notable because it is a product in almost all decays of the top quark and is a frequent decay product for the Higgs boson.
</p>
<section data-min-level="1">
<h4>The bottom (or beauty) quark</h4>
<img class="img-responsive" src="assets/info/b.png" alt="A plot from one of the original publications" align="center">
<p>
The bottom (or beauty) quark is a third-generation quark with a charge of &minus;&frac13;. It has a large mass (around 4.2 GeV/c<sup>2</sup> — more that four times the mass of a proton!). The bottom quark is notable because it is a product in almost all decays of the top quark and is a frequent decay product for the Higgs boson.
</p>
</section>

<h5><b>History of the discovery</b></h5>
<p>
The bottom quark was predicted in 1973 by physicists Makoto Kobayashi and Toshihide Maskawa as part of their explanation for CP violation. The name “bottom” was introduced in 1975 by Haim Harari. The bottom quark was discovered in 1977 by the Fermilab E288 experiment team led by Leon M. Lederman, when collisions produced bottomonia (mesons with a bottom quark and its antiquark). Kobayashi and Maskawa won the 2008 Nobel Prize in Physics for their explanation of CP violation. Upon its discovery, there were efforts to name the bottom quark “beauty”, but “bottom” became the predominant name.
</p>
<section data-min-level="5">
<h5>History of the discovery</h5>
<p>
The bottom quark was predicted in 1973 by physicists Makoto Kobayashi and Toshihide Maskawa as part of their explanation for CP violation. The name “bottom” was introduced in 1975 by Haim Harari. The bottom quark was discovered in 1977 by the Fermilab E288 experiment team led by Leon M. Lederman, when collisions produced bottomonia (mesons with a bottom quark and its antiquark). Kobayashi and Maskawa won the 2008 Nobel Prize in Physics for their explanation of CP violation. Upon its discovery, there were efforts to name the bottom quark “beauty”, but “bottom” became the predominant name.
</p>
</section>

<hr>
<h5><b>Resources</b></h5>
<ul>
<li><a href="http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.39.252" target="_blank">The original presentation of S. W. Herb et al.</a></li>
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28 changes: 18 additions & 10 deletions html/tau.html
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<p class="lead">You discovered the τ lepton!</p>
<h5><b>The τ lepton</b></h5>
<img class="img-responsive" src="assets/info/tau.png" alt="A plot from the original publication" align="right">
<p>
The τ (tau) is an elementary particle that can be thought of as a much heavier cousin of the electron, with a spin of &frac12;. It belongs to the family of leptons, along with the electron, the muon, and the three neutrinos. Despite the origin of the word lepton (meaning fine, small, thin) the τ is very massive at 1776.82 MeV/c<sup>2</sup>, which is nearly 3500 times the mass of the electron and around twice the mass of the proton.
</p>

<h5><b>The discovery of the τ</b></h5>
<p>
The τ was detected in a series of experiments between 1974 and 1977 by Martin Lewis Perl and his colleagues at the SLAC-LBL group. Their equipment consisted of SLAC’s then-new e<sup>+</sup>e<sup>&minus;</sup> colliding ring, called SPEAR, and the LBL magnetic detector. They could detect and distinguish between leptons, hadrons and photons.<br>
Martin Perl shared the 1995 Nobel Prize in Physics with Frederick Reines. The latter was awarded his share of the prize for experimental discovery of the neutrino.
</p>
<section data-min-level="1">
<h4>The τ lepton</h4>
<img class="img-responsive" src="assets/info/tau.png" alt="A plot from the original publication" align="right">
<p>
The τ (tau) is an elementary particle that can be thought of as a much heavier cousin of the electron, with a spin of &frac12;. It belongs to the family of leptons, along with the electron, the muon, and the three neutrinos. Despite the origin of the word lepton (meaning fine, small, thin) the τ is very massive at 1776.82 MeV/c<sup>2</sup>, which is nearly 3500 times the mass of the electron and around twice the mass of the proton.
</p>
</section>

<section data-min-level="5">
<h5>The discovery of the τ</h5>
<p>
The τ was detected in a series of experiments between 1974 and 1977 by Martin Lewis Perl and his colleagues at the SLAC-LBL group. Their equipment consisted of SLAC’s then-new e<sup>+</sup>e<sup>&minus;</sup> colliding ring, called SPEAR, and the LBL magnetic detector. They could detect and distinguish between leptons, hadrons and photons.
</p>
<p>
Martin Perl shared the 1995 Nobel Prize in Physics with Frederick Reines. The latter was awarded his share of the prize for experimental discovery of the neutrino.
</p>
</section>

<hr>
<h5><b>Resources</b></h5>
<ul>
<li><a href="http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.35.1489" target="_blank">The original publication by M. L. Perl et al.</a></li>
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