Benedetta Belfatto: Minimally modified Fritzsch texture for quark masses and CKM mixing

Tuesday 7 Nov 2023, 14:00 → 15:00 Europe/Ljubljana

https://zoom.us/j/3601731049?pwd=bVNQRjUxU2ExZ0cveWcxYXNUUGdjZz09 (F1 tea room)

The Standard Model does not constrain the form of the Yukawa matrices and thus the origin of fermion mass hierarchies and mixing pattern remains a mystery. On the other hand, there are intriguing relations between fermion masses and mixing angles which may point towards specific textures of Yukawa matrices, such as the zero texture proposed by Fritszch. However the original (symmetric) Fritzsch ansatz is excluded by present precision tests since it predicts a too large value of $|V_{cb}|$ as well as a too small value of the ratio $|V_{ub}/V_{cb}|$.
I will discuss a minimal modification which still maintains the six zero entries as in the original Fritzsch ansatz, that is the introduction an asymmetry between the 23 and 32 entries in the down-quark Yukawa matrix.  This flavour structure can naturally emerge in the context of models with inter-family $SU(3)_H$ symmetry and its predictions are perfectly compatible with the present precision data on quark masses and CKM mixing matrix.