مطالعه سهم همبستگی سمتی در واپاشی کوارک تاپ قطبیده: در جستجوی فیزیک جدید

نوع مقاله : مقاله پژوهشی کامل

نویسندگان

دانشکده فیزیک، دانشگاه یزد، یزد، ایران

چکیده

مطالعه واپاشی کوارک تاپ قطبیده می‌تواند به عنوان کانالی برای جستجوی فیزیک جدید در نظر گرفته شود. مطابق با مدل استاندارد فیزیک ذرات بنیادی، کوارک تاپ در فرایند آبشاری به کوارک باتم و بوزون واپاشیده می‌شود که در ادامه، بوزون به زوج لپتونها (یا کوارک-آنتی کوارک) و کوارک باتم نیز در فرایند هادرونی شدن به مزون یا باریون قابل مشاهده (معمولاً مزون ) تبدیل می‌شود. در این مقاله با مطالعه‌ی نرخ واپاشی کورک تاپ قطبیده به بررسی جزئی‌تر سهم همبستگی سمتی بین صفحه رویداد، تشکیل شده از بردارهای ، و صفحه قطبی متشکل از بردار قطبش کوارک تاپ، پرداخته و اثرات جریان‌های کوارکی دستگونه-راستگرد را بر این سهم بررسی می‌کنیم. نشان خواهیم داد که این جریان‌های غایب در مدل استاندارد چگونه باعث ایجاد سهمی غیر صفر در مرتبه اول اختلال برای همبستگی سمتی مذکور خواهند شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

The study of azimuthal correlation contribution in polarized top quark decay: Search for new physics

نویسندگان [English]

  • Seyed Mohammad Moosavi Nejad
  • Taghi Ebrahimi
Department of physics, Yazd university, Yazd, Iran
چکیده [English]

The study of polarized top quark decay could be considered as a new channel to search for new physics. According to the Standard Model (SM) of particle physics, top quark in a cascade process as decays into a bottom quark and -boson so in the following, -boson decays in a lepton pair (or a quark-antiquark) and bottom hadronizes into an observable bottom-flavored hadron (in most cases a B-meson). Through this paper, we first present an overview on the polarized top quark decay and then study the azimuthal correlation between the event plane, formed by the vectors , and the polar plane constructed by the vectors . We will investigate the effect of right-chiral quark current which is absent in the SM. We will show that this non-SM effect leads to nonzero values for the azimuthal correlation contribution at leading-order perturbation theory.

کلیدواژه‌ها [English]

  • Polarized Top quark
  • Standard model
  • Left and right chiral currents
  • Azimuthal correlation
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