Центральне ексклюзивне продукування на LHCb

Автор(и)

  • C. Van Hulse University College Dublin

DOI:

https://doi.org/10.15407/ujpe64.7.595

Ключові слова:

exclusive photoproduction, ultra-peripheral collisions, generalised parton distributions, parton distribution functions

Анотація

Колаборацiя LHCb мiряла центральне ексклюзивне продукування мезонiв J/ф, ф(2S) i ϒ мезонiв, а також мезонних пар J/фJ/ф, J/фф(2S), ф(2S)ф(2S), xcxc в протон-протонних зiткненнях. Аналiз пар мезонiв ϒ та шармонiя виконано при енергiях в системi центра мас 7 та 8 ТеВ, а для J/ф та ф(2S) – при 7 та 13 ТеВ. В аналiзi при 13 ТеВ були задiянi новi лiчильники, якi зменшують фон вiдсiкаючи подiї з активнiстю в широкому iнтервалi швидкостей. Вимiри центрального ексклюзивного продукування на LHCb чутливi до глюонних розподiлiв для значень бйоркенiвської змiнної аж до 2 · 10−6 при 13 ТеВ. Нами представлено огляд результатiв LHCb та їх порiвняння з iснуючими вимiрами в iнших експериментах, а також з теоретичними обрахунками.

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Опубліковано

2019-09-17

Як цитувати

Van Hulse, C. (2019). Центральне ексклюзивне продукування на LHCb. Український фізичний журнал, 64(7), 595. https://doi.org/10.15407/ujpe64.7.595

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