8–10 May 2017
University of Pittsburgh
US/Eastern timezone

$D^*$ polarization as a probe to discriminate new physics in $\bar{B} \to D^* \tau \bar{\nu}$

9 May 2017, 14:45
15m
G-31 (Benedum Hall)

G-31

Benedum Hall

parallel talk Heavy Flavor

Speaker

Prof. Sankagiri Umasankar (Indian Institute of Technology Bombay)

Description

\begin{abstract}
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 identified 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

Dr Ashutosh Kumar Alok (Indian Institute of Technology Jodhpur) Dr Dinesh Kumar (University of Rajasthan, Jaipur) Mr Suman Kumbhakar (Indian Institute of Technology Bombay)

Presentation materials