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pentaquark

British  
/ ˈpɛntəˌkwɑːk /

noun

  1. physics a postulated subatomic particle consisting of four quarks and one antiquark, thought not to exist in actuality

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of pentaquark

C21

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The observation of a new type of pentaquark and the first duo of tetraquarks at CERN, the Geneva-area home to the Large Hadron Collider, offers a new angle to assess the “strong force” that holds together the nuclei of atoms.

From Seattle Times

The new pentaquark decays into particles that none of the others produce, while the two tetraquarks have the same mass, suggesting they may be the first known pair of exotic structures.

From BBC

Scientists at the Large Hadron Collider in Switzerland have discovered one new pentaquark and two tetraquarks.

From BBC

They also find a lighter pentaquark at 4312 MeV.

From Science Magazine

The lightest pentaquark has a mass just below the sum of a particular baryon and meson that together contain the correct quark ingredients.

From Science Magazine