# First measurement of the decay-time-integrated $C\!P$ asymmetry in $B_s^0 \to D_s^- \pi^+$ decays at LHCb

- Institution: CERN
- Speaker: Jamie Gooding
- Year: 2026
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3020674)
- Licence: [CERN](https://copyright.web.cern)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

Tensions between measured and predicted branching fractions of non-leptonic $B_{(s)}^0 \to D_{(s)}^{(\ast)-} h^+$ decays may be explained by the presence of new physics (NP) contributions capable of inducing $C\!P$ asymmetries up to O(1%). The $C\!P$ asymmetry of flavour-specific $B_s^0 \to D_s^-\pi^+$ decays provides a clean test for NP. This can be measured by the LHCb experiment as the flavour-untagged decay-time-integrated $C\!P$ asymmetry, $\langle A^s_{\rm untagged} \rangle$. This seminar presents the first measurement of $\langle A^s_{\rm untagged} \rangle$, performed using $5.4~{\rm fb}^{-1}$ of $pp$ collision data recorded by the LHCb experiment between 2016 and 2018 at a centre-of-mass energy of $13~{\rm TeV}$.

Refreshments will be served at 10h30

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## Lectures

1. [First measurement of the decay-time-integrated $C\!P$ asymmetry in $B_s^0 \to D_s^- \pi^+$ decays at LHCb](https://invisiblenetwork.ai/learn/cern/3020674/7904d3d24ab1), 52 min (CERN's player)