Speaker
Prof.
Sankagiri Umasankar
(Indian Institute of Technology Bombay)
Description
The confirmation of excess in $R_{D^*}$ at the LHCb is an indication of
lepton flavor non-universality. Various different new physics operators
and their coupling strengths, which provide a good fit to $R_D$, $R_{D^*}$
and $q^2$ spectra, were identfied previously. In this work, we try to find
angular observables in $\bar{B} \to D^* \tau \bar{\nu}$ which enable us to distinguish between these new physics operators. We find that $D^*$ polarization fraction $f_L(q^2)$ is a good discriminant of scalar and tensor new physics operators. The change in $\langle f_L(q^2) \rangle$, induced by scalar and tensor operators, is about three times larger than the expected uncertainty in the upcoming Belle measurement.
Primary author
Prof.
Sankagiri Umasankar
(Indian Institute of Technology Bombay)
Co-authors
Prof.
Ashuotsh Kumar Alok
(Indian Institute of Technology Jodhpur)
Dr
Dinesh Kumar
(University of Rajasthan, Jaipur)
Mr
Suman Kumbhakar
(Indian Institute of Technology Bombay)
