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تسجيل مستخدم جديدتدرج الذوق الوحيد في QCD المتعدد الأذواق
Flavor-singlet spectrum in multi-flavor QCD
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إن الدراسة في النظم المقياس SU(3) مع زيادة عدد الفرميونات الخفيفة ذات صلة بالشأن الذي يتعلق بتحليل ديناميكي القوي ل QCD وببناء امتدادات تفاعلية قوية لنموذج المعيار (مثل اكمال UV لنماذج الهيجس المركبة). للتباين من هذه النظم التفاعلية التي تحتوي على العديد من النكهات، نحن ندرس المذبذب الوحيد النكهة كمستقبل مثير للاهتمام. في الواقع، بعض نماذج الهيجس المركبة تتطلب أن يكون الهيجس أصغر سكالار في المذبذب الوحيد النكهة في المذبذب الذي يحتوي على هرم بين الدوال المتبقية من القطاع الجديد الذي يتفاعل قويا. بالإضافة إلى ذلك، يمكن أن تؤثر إدخال العديد من النكهات الخفيفة على عدد محدد من الألوان على ديناميكي الأصغر سكالار الوحيد النكهة. نقدم الدراسة الجارية لهذه القنوات الوحيدة النكهة باستخدام معالجي التقاط المتعددة على أجيال عالية الإحصائية التي تم إنشاؤها من قبل مشاركة LatKMI ونقارن النتائج مع البيانات المتوفرة التي تم الحصول عليها من قبل مشاركة الحد القوي اللاطيق. للنظام الذي يحتوي على 8 نكهات، قامت المشاركتان بإنشاء التكوينات التي تتناسب مع بعضها البعض مع الغرض من التعامل مع الحد الصفري باستخدام أكبر قياسات ممكنة.
Studying SU(3) gauge theories with increasing number of light fermions is relevant both for understanding the strong dynamics of QCD and for constructing strongly interacting extensions of the Standard Model (e.g. UV completions of composite Higgs models). In order to contrast these many-flavors strongly interacting theories with QCD, we study the flavor-singlet spectrum as an interesting probe. In fact, some composite Higgs models require the Higgs boson to be the lightest flavor-singlet scalar in the spectrum of a strongly interacting new sector with a well defined hierarchy with the rest of the states. Moreover, introducing many light flavors at fixed number of colors can influence the dynamics of the lightest flavor-singlet pseudoscalar. We present the on-going study of these flavor-singlet channels using multiple interpolating operators on high-statistics ensembles generated by the LatKMI collaboration and we compare results with available data obtained by the Lattice Strong Dynamics collaboration. For the theory with 8 flavors, the two collaborations have generated configurations that complement each others with the aim to tackle the massless limit using the largest possible volumes.
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