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Abstract Charged-particle trajectories are usually reconstructed with the LHCb detector using combined information from the tracking devices placed upstream and downstream of the 4 T m dipole magnet. Trajectories reconstructed using only information from the tracker downstream of the dipole magnet, which are referred to as T tracks, have not been used for physics analysis to date. The challenges of the reconstruction of long-lived particles with T tracks for physics use are discussed and solutions are proposed. The feasibility and the tracking performance are studied using samples of long-lived$${\Lambda }$$ and$$K_S^0$$ hadrons decaying between 6.0 and 7.6 m downstream of the proton–proton collision point, thereby traversing most of the magnetic field region and providing maximal sensitivity to magnetic and electric dipole moments. The reconstruction can be expanded upstream to about 2.5 m for use in direct searches of exotic long-lived particles. The data used in this analysis have been recorded between 2015 and 2018 and correspond to an integrated luminosity of 6 $$\hbox {fb}^{-1}$$ . The results obtained demonstrate the possibility to further extend the decay volume and the physics reach of the LHCb experiment.
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Nonparametric Reconstruction of Vector Fields From Noisy Observations of Their Flow Curves
In an ordinary differential equation represented by a set of state-space equations, the differential of the state vector is given by the values of a vector field evaluated at the values of the state vector. This paper focuses on the reconstruction of this vector field from noisy measurements of the state trajectories generated empirically from a physical process. For this estimation problem, a nonparametric least squares formulation is presented, which is then expressed as a linear quadratic tracking problem with a well known solution from the optimal control theory. This approach is demonstrated for experimental reconstruction of the magnetic force field around a permanent magnet from the motion trajectories of a magnetic particle attracted toward the magnet.
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- Award ID(s):
- 1941944
- PAR ID:
- 10295036
- Date Published:
- Journal Name:
- 2021 American Control Conference (ACC 2021)
- Page Range / eLocation ID:
- 3969 to 3974
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.23919/ACC50511.2021.9482622
