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Upsilon particles

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Upsilon particles

A family of elementary particles whose first three members were discovered in 1977. The upsilon mesons, &Ugr;, are the heaviest known vector mesons, with masses greater than 10 times that of the proton. They are bound states of a heavy quark and its antiquark. The quarks which bind to form the upsilons carry a new quantum number called beauty or bottomness, and they are called b-quarks or b. The mass of the b-quark is around 5 GeV. The anti-b-quark or b carries antibeauty, and therefore the upsilons carry no beauty and are often called hidden beauty states. Direct proof of the existence of the b-quark was obtained by observing the existence of B mesons which consist of a b-quark bound to a lighter quark. Thirteen bb-mesons have also been observed thus far. See Elementary particle, Meson, Quarks

McGraw-Hill Concise Encyclopedia of Physics. © 2002 by The McGraw-Hill Companies, Inc.
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The thread that apparently leaked from the fraternity's chat group was circulated on social media last week, prompting University of the Philippines president and Upsilon member Danilo Concepcion to issue a statement denouncing the conversation and vow an investigation.
"I assure the University community that I will do all I can, both as President and as fellow of the fraternity to root out this problem and to instil or to reaffirm a culture of respect, tolerance and decency within Upsilon and our entire fraternity system," Concepcion also said.
Meanwhile, Concepcion assures the UP community that "I will do all I can, both as president and as a fellow of the fraternity, to root out this problem and to instill or reaffirm a culture of respect, tolerance, and decency within Upsilon and our entire fraternity system."
IN FORM Upsilon Bleu in action at Kelso in February
RenaissanceRe Holdings Ltd (NYSE:RNR), a provider of reinsurance and insurance, stated on Thursday that it has formed a new Bermuda domiciled special purpose insurance vehicle, Upsilon Reinsurance II Ltd (Upsilon Re II), creating additional reinsurance capacity in the global aggregate retrocessional reinsurance market.
This scarcity is the main reason that upsilon cells have been so difficult to discover.
Part of his nonchalance no doubt stems from the fact that kegs are already prohibited at the eight or so bashes a month that his fraternity, Delta Upsilon, helps throw.
In the search for excellence and professional commitment to the computing and information technology field, the Executive Council of Upsilon Pi Epsilon (UPE) and the Membership Activities Board of ACM announces the UPE ACM Student Chapter Scholarship Award.
One star, Upsilon Andromedae, is located 44 light years (the distance light travels in one year--about 6 trillion miles or 9.5 trillion kilometers) away, and can be seen from Earth with the naked eye (see star map, p.
The messages have been linked with the fraternity Upsilon Sigma Phi, which has chapters in U.P.
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