In:
Journal of High Energy Physics, Springer Science and Business Media LLC, Vol. 2023, No. 7 ( 2023-07-13)
Abstract:
The first observation of the $$ {B}_s^0 $$ B s 0 → D ∗+ D ∗ − decay and the measurement of its branching ratio relative to the B 0 → D ∗+ D ∗ − decay are presented. The data sample used corresponds to an integrated luminosity of 9 fb − 1 of proton-proton collisions recorded by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV between 2011 and 2018. The decay is observed with more than 10 standard deviations and the time-integrated ratio of branching fractions is determined to be $$ \frac{\mathcal{B}\left({B}_s^0\to {D}^{\ast +}{D}^{\ast -}\right)}{\mathcal{B}\left({B}^0\to {D}^{\ast +}{D}^{\ast -}\right)}=0.269\pm 0.032\pm 0.011\pm 0.008, $$ B B s 0 → D ∗ + D ∗ − B B 0 → D ∗ + D ∗ − = 0.269 ± 0.032 ± 0.011 ± 0.008 , where the first uncertainty is statistical, the second systematic and the third due to the uncertainty of the fragmentation fraction ratio f s /f d . The $$ {B}_s^0 $$ B s 0 → D *+ D * − branching fraction is calculated to be $$ \mathcal{B}\left({B}_s^0\to {D}^{\ast +}{D}^{\ast -}\right)=\left(2.15\pm 0.26\pm 0.09\pm 0.06\pm 0.16\right)\times {10}^{-4}, $$ B B s 0 → D ∗ + D ∗ − = 2.15 ± 0.26 ± 0.09 ± 0.06 ± 0.16 × 10 − 4 , where the fourth uncertainty is due to the B 0 → D * + D *− branching fraction. These results are calculated using the average $$ {B}_s^0 $$ B s 0 meson lifetime in simulation. Correction factors are reported for scenarios where either a purely heavy or a purely light $$ {B}_s^0 $$ B s 0 eigenstate is considered.
Type of Medium:
Online Resource
ISSN:
1029-8479
DOI:
10.1007/JHEP07(2023)119
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2023
detail.hit.zdb_id:
2027350-2
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