@Article{LHCbCollaborationAaij_etal2021,
author="LHCb Collaboration (Aaij, R. et al
and Henry, L.
and Jashal, B. K.
and Martinez-Vidal, F.
and Oyanguren, A.
and Remon Alepuz, C.
and Ruiz Vidal, J.",
title="Angular analysis of B0 -> D*- D*s+ with D*s+ -> Ds + gamma decays",
journal="Journal of High Energy Physics",
year="2021",
publisher="Springer",
volume="06",
number="6",
pages="177--30pp",
optkeywords="B physics; Branching fraction; Hadron-Hadron scattering (experiments); Polarization",
abstract="The first full angular analysis of the B0 -> D-Ds+ decay is performed using 6 fb(-1) of pp collision data collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The Ds+-> Ds+gamma and D*- -> D<overbar></mml:mover>0- vector meson decays are used with the subsequent Ds+ -> K+K-pi (+) and D<overbar></mml:mover>0 -> K+pi (-) decays. All helicity amplitudes and phases are measured, and the longitudinal polarisation fraction is determined to be f(L) = 0.578 +/- 0.010 +/- 0.011 with world-best precision, where the first uncertainty is statistical and the second is systematic. The pattern of helicity amplitude magnitudes is found to align with expectations from quark-helicity conservation in B decays. The ratio of branching fractions [B(B0 -> D-Ds+) x B(Ds+-> Ds+gamma)]/B(B-0 -> D(*-)Ds+) is measured to be 2.045 +/- 0.022 +/- 0.071 with world-best precision. In addition, the first observation of the Cabibbo-suppressed B-s -> D(*-)Ds+ decay is made with a significance of seven standard deviations. The branching fraction ratio B(B-s -> D(*-)Ds<mml:mo>+)/B(B-0 -> D(*-)Ds<mml:mo>+) is measured to be 0.049 +/- 0.006 +/- 0.003 +/- 0.002, where the third uncertainty is due to limited knowledge of the ratio of fragmentation fractions.<fig id={\textquoteleft}{\textquoteleft}Figa{\textquoteright}{\textquoteright} position={\textquoteleft}{\textquoteleft}anchor{\textquoteright}{\textquoteright}><graphic position={\textquoteleft}{\textquoteleft}anchor{\textquoteright}{\textquoteright} specific-use={\textquoteleft}{\textquoteleft}HTML{\textquoteright}{\textquoteright} mime-subtype={\textquoteleft}{\textquoteleft}JPEG{\textquoteright}{\textquoteright} xmlns:xlink={\textquoteleft}{\textquoteleft}http://www.w3.org/1999/xlink{\textquoteright}{\textquoteright} xlink:href={\textquoteleft}{\textquoteleft}MediaObjects/13130{\textit{}2021{}}16089{\textit{}Figa{}}HTML.jpg{\textquoteright}{\textquoteright} id={\textquoteleft}{\textquoteleft}MO1{\textquoteright}{\textquoteright}></graphic",
optnote="WOS:000671168600002",
optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=4890), last updated on Wed, 11 Aug 2021 09:27:56 +0000",
issn="1029-8479",
doi="10.1007/JHEP06(2021)177",
opturl="https://arxiv.org/abs/2105.02596",
opturl="https://doi.org/10.1007/JHEP06(2021)177",
language="English"
}