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Hi Gentlemen, This week we'll discuss the new "exotic hadrons" result from Belle that Frank suggested (see below). The paper ref is http://arxiv.org/abs/1110.2251, and rumors in BaBar have it that the interactions newswire post appeared once the preprint was accepted by PRL. Dial-in is ReadyTalk 866-740-1260, code 3144955 at 2 PM Eastern as usual. Thank you, --Ray > ---------- Forwarded message ---------- > Date: Tue, 10 Jan 2012 03:00:15 -0600 (CST) > From: Interactions News Wire <[log in to unmask]> > To: [log in to unmask] > Subject: [Interactions News Wire] #02-12 - KEK: Belle Discovers New Heavy > 'Exotic Hadrons' > > Interactions NewsWire #02-12 > 10 January 2012 http://www.interactions.org > ******************************************* > Source: KEK > Content: Press Release > Date Issued: 10 January 2012 > ******************************************* > > Belle Discovers New Heavy 'Exotic Hadrons' > > Two unexpected new hadrons containing bottom quarks have been discovered > by the Belle Experiment using the High Energy Accelerator Research > Organization (KEK)'s B Factory (KEKB), a highly-luminous, > electron?positron collider. These new particles have electric charge and > are thought to be "exotic" hadrons -- non-standard hadrons, containing at > least four quarks. Previously, a series of new and unexpected exotic > hadrons containing charm and anti-charm quarks have been observed. This > latest discovery from Belle demonstrates the existence of exotic hadrons > containing at least four quarks in a particle system including bottom > quarks . > > The Belle Experiment has discovered two new unexpected particles at the > KEK B Factory (KEKB). These new particles, termed Z(sub)b, contain both > one 'bottom' quark (the second-heaviest quark among the known six types of > quarks) and one 'anti-bottom' quark (the anti-particle of the bottom > quark). Moreover, they have electric charge and thus are thought to be > hadrons in which at least two additional quarks other than the bottom > quark and anti-bottom quark (at least four quarks in total) are bound > together. > > A large amount of data containing particles produced in electron?position > collisions using the KEKB accelerator, which has achieved the world's > highest luminosity, has been obtained. While focusing on 'bottomonia,' > heavy mesons composed of one bottom quark and one anti-bottom quark, we > conducted a detailed analysis of events involving two types of bottomonia, > the Upsilon and the h(sub)b. This analysis revealed two new unanticipated > charged particles that decay into a bottomonium (Upsilon or h(sub)b) and a > charged pi meson (pi ±), which were then called "Z(sub)b(10610)" and > "Z(sub)b(10650)" according to their mass values, 10610 and 10650 MeV/c^2, > respectively. They are approximately eleven times heavier than a proton. > In principle, a bottomonium particle?s charge is zero; therefore, these > charged Z(sub)b particles should have at least two more quarks, e.g. one > 'up' quark and one 'anti-down' quark. > > Several hundred mesons have been identified to date. All of them are > thought to be bound states of one quark and one anti-quark, with the > binding provided via the strong interaction of elementary particles. Using > the KEKB accelerator, however, the Belle experiment has discovered more > than ten 'exotic hadrons,' including the X(3872), Y(3940), and Z(4430), > which were not anticipated by existing theories. These new particles, > which are about 4?4.5 times heavier than a proton, may be exotic hadrons > consisting of one 'charm' quark and one 'anti-charm' quark plus two more > different types of lighter quarks. These unexpected discoveries have > attracted the attention of researchers around the world. The latest > discovery has revealed the existence of exotic hadrons containing bottom > quarks, which are heavier than charm quarks. > > The Belle B Factory experiment, which began in 1999 with the aim of > elucidating the origin of particle?anti-particle symmetry breaking (CP > violation), has contributed to the Nobel Prize in Physics in 2008 awarded > to Drs. Kobayashi and Maskawa. Moreover, data obtained from > electron?positron collisions with the world's highest luminosity achieved > at the KEKB accelerator have resulted in a series of unexpected > discoveries of exotic hadrons, opening a new research frontier in particle > physics. Data taking at the Belle Experiment has already been completed, > but a vast amount of data is still awaiting detailed analysis. Moreover, > an upgraded version of the KEKB/Belle Experiment, called SuperKEKB/Belle > II is currently being prepared. Belle II aims to collect 50 times more > data than the earlier experiment. Researchers are eagerly awaiting the > opportunity to explore the full spectrum of exotic hadrons containing > various types of quarks, including strange quarks, as well as charm and > bottom quarks, which are expected to be discovered in the future at the > SuperKEKB/Belle II Experiment. It is worth noting that quarks are bound by > the strong interaction and confined to composite particles, such as > mesons, and thus cannot exist individually as free particles. The detailed > exploration of exotic hadrons will advance the understanding of how and > what types of hadrons are possible based on the mechanisms defined by > quantum chromodynamics, which describes the strong interaction. > > A paper reporting this achievement has been accepted for publication by > Physical Review Letters on December 30, 2011, and will be published > shortly. > > Full release, with images and glossary, is available at: > http://www.kek.jp/intra-e/press/2012/011014/ > > Contact Information > > About the details of the present study > Professor Yoshihide Sakai > Co-spokesperson, the Belle Collaboration > The High Energy Accelerator Research Organization > TEL: 81-29-864-5335 > FAX: 81-29-864-5340 > E-mail: [log in to unmask] > > Professor Toru Iijima > Co-spokesperson, the Belle Collaboration > The Center for Experimental Studies, the Kobayashi?Maskawa Institute for > the Origin of Particles and the Universe, Nagoya University > TEL: 81-52-789-2893 > FAX: 81-52-782-5752 > E-mail: [log in to unmask] > > Professor Thomas Browder > Co-spokesperson, the Belle Collaboration > University of Hawaii > TEL: 1-808-956-2936 > FAX: 1-808-956-2930 > E-mail: [log in to unmask] > > Public relations > Yohei Morita > Public Relations Officer > The High Energy Accelerator Research Organization > TEL: 81-29-879-6047 > FAX: 81-29-879-6049 > E-mail: [log in to unmask] > > To unsubscribe from the Interactions News Wire, please email [log in to unmask] with "remove" in the subject line. > > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the LQS-L list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=LQS-L&A=1 > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the LQS-L list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=LQS-L&A=1 > > ######################################################################## > Use REPLY-ALL to reply to list > > To unsubscribe from the LQS-L list, click the following link: > https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=LQS-L&A=1 ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the LQS-L list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=LQS-L&A=1