# Measurements of $\phi_s$ at the LHCb experiment

## TL;DR

This paper reviews the current status of $\,phi_s$ CP-violation measurements at LHCb, introduces a new decay mode observation, and discusses future improvements in measurement precision with larger data samples.

## Contribution

It reports the first observation of the $B_s^0\to\eta_c\phi$ decay mode and discusses how future data will enhance $\,phi_s$ measurement accuracy.

## Key findings

- Observation of $B_s^0\to\eta_c\phi$ decay mode
- Current measurements align with Standard Model expectations
- Future data will significantly improve measurement precision

## Abstract

These proceedings present the current status of measurements of the CP-violating phase $phi_s$ by the LHCb collaboration, reviewing the measurements in channels such as $B_s^0\to J/\psi\phi$, $B_s^0\to J/\psi \pi^+\pi^-$ and $B_s^0 \to \psi(2S)\phi$. The observation of the $B_s^0\to\eta_c\phi$ decay mode is presented for the first time, which can be used to measure $\phi_s$ with larger data samples that will be collected over the coming years by the LHCb experiment. Finally, the expected increase in precision from LHCb measurements of $\phi_s$ over the next decade is presented.