Alternating Gradient Synchrotron

<h2 id="importance-of-alternate-gradient-focusing">Importance of alternate-gradient focusing</h2>
<blockquote><p>It became increasingly clear that if further progress was to be made in high energy nuclear physics by experiments using artificially accelerated particles some new principle must be found that would cheapen the cost per GeV. It was lucky for CERN that just at the time a European machine was being considered this new principle was discovered. The problem was simple enough. A cheaper machine could be built if the amplitudes of the free and forced oscillations of the accelerating particles could be decreased in some way so that the vacuum chamber size and the cross-section of the magnet ring could be reduced. The simplest way to reduce the amplitude of the free oscillations is to increase the frequency by increasing the restoring force, and although this is easy to achieve in the vertical direction by increasing the magnetic field gradient, the condition for horizontal stability is violated if n exceeds unity.The new principle discovered by <a href="/facts/Nicholas_Christofilos/b4914g3p">Christofilos</a> and <a href="/facts/Ernest_Courant/UjqLSINc">Courant</a>, <a href="/facts/M._Stanley_Livingston/SLXfr1jo">Livingston</a> and <a href="/facts/Hartland_Snyder/2MjwM6RU">Snyder</a> increases the frequency of the <a href="/facts/Betatron_oscillations/fpNcRWQ3">betatron oscillations</a> by alternating the sign of the gradient of the magnetic field. The structure of the magnet is no longer uniform round the ring with a constant gradient but is broken up into sectors whose gradient is alternatively positive and negative.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a></p>— J.B. Adams, "The Alternating Gradient Proton Synchrotron"</blockquote>
<h2 id="nobel-prizes">Nobel Prizes</h2>
<p>The work performed at the accelerator led to three <a href="/facts/Nobel_Prize_in_Physics/o6w1nCbr">Nobel Prizes in Physics</a>: 
</p>
<ul><li>1976: <a href="/facts/Samuel_C._C._Ting/qushtWqK">Samuel C. C. Ting</a> discovered the <i>J</i> part of the <a href="/facts/J%2f%25CF%2588_meson/gPC3MUrM"><i>J</i>/ψ</a> and the <a href="/facts/Charm_quark/RLduBtpL">charm quark</a>.</li>
<li>1980: <a href="/facts/James_Cronin/gMGryPaJ">James Cronin</a> and <a href="/facts/Val_Fitch/Mtz5Wub0">Val Fitch</a> discovered <a href="/facts/CP_violation/Nu5lCsPI">CP violation</a> by experimenting with <a href="/facts/Kaon/Yn2w4QlQ">Kaons</a>.</li>
<li>1988: <a href="/facts/Leon_Lederman/3UT17nBB">Leon Lederman</a>, <a href="/facts/Melvin_Schwartz/UApASDpn">Melvin Schwartz</a> and <a href="/facts/Jack_Steinberger/JUd5e2pJ">Jack Steinberger</a> discovered the <a href="/facts/Muon_neutrino/A8kPHDKd">muon neutrino</a>.</li></ul>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Strong_focusing/hG5pbII4">Strong focusing</a> (also known as alternating-gradient focusing — an idea pioneered on this accelerator)</li></ul>

<h2 id="further-reading">Further reading</h2>
<ul><li>Abraham Pais (1988). <i>Inward Bound: of matter and forces in the physical world</i>. Oxford University Press. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-19-851997-3.</li></ul>
<h2 id="external-links">External links</h2>

Wikimedia Commons has media related to Alternating Gradient Synchrotron.

<ul><li><a href="https://www.bnl.gov/rhic/AGS.asp">Brookhaven National Laboratory: Alternating Gradient Synchrotron web page</a></li>
<li>Beth, R. A.; Lasky, C. (1958). "The Brookhaven Alternating Gradient Synchrotron: Construction of a massive nuclear research machine requires ideas, men, and methods from many fields". <i>Science</i>. 128 (3336): 1393–1401. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1126%2Fscience.128.3336.1393">10.1126/science.128.3336.1393</a>. <a href="/facts/PMID_(identifier)/JlHAvMHt">PMID</a> <a href="https://pubmed.ncbi.nlm.nih.gov/17797589">17797589</a>.</li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Adams, J. B. (1955). "The Alternating Gradient Proton Synchrotron" (PDF). Nuovo Cimento. 2 (S1): 355–374. Bibcode:1955NCim....2S.355A. doi:10.1007/BF02746095. S2CID 121596010, N. 1 del Supplemento al Vol. 2, Serie X, del Nuovo Cimento{{cite journal}}:  CS1 maint: postscript (link) (quote from p. 359) <a href="/wiki/John_Adams_(physicist)" target="_blank">/wiki/John_Adams_(physicist)</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
</ol>

Alternating Gradient Synchrotron open-in-new

Alternating Gradient Synchrotron