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Radiative $b$-baryon decays to measure the photon and $b$-baryon polarization

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 نشر من قبل Shibasis Roy
 تاريخ النشر 2019
  مجال البحث
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The radiative decays of $b$-baryons facilitate the direct measurement of photon helicity in $bto sgamma$ transitions thus serving as an important test of physics beyond the Standard Model. In this paper we analyze the complete angular distribution of ground state $b$-baryon ($Lambda_{b}^{0}$ and $Xi_{b}^{-}$) radiative decays to multibody final states assuming an initially polarized $b$-baryon sample. Our sensitivity study suggests that the photon polarization asymmetry can be extracted to a good accuracy along with a simultaneous measurement of the initial $b$-baryon polarization. With higher yields of $b$-baryons, achievable in subsequent runs of the Large Hadron Collider (LHC), we find that the photon polarization measurement can play a pivotal role in constraining different new physics scenarios.



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