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.
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)
