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arXiv · 2308.00619

A quantum algorithm for track reconstruction in the LHCb vertex detector

Davide Nicotra·Miriam Lucio Martinez·Jacco Andreas de Vries·Marcel Merk·Kurt Driessens·Ronald Leonard Westra·Domenica Dibenedetto·Daniel Hugo Cámpora Pérez
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Abstract

High-energy physics is facing increasingly computational challenges in real-time event reconstruction for the near-future high-luminosity era. Using the LHCb vertex detector as a use-case, we explore a new algorithm for particle track reconstruction based on the minimisation of an Ising-like Hamiltonian with a linear algebra approach. The use of a classical matrix inversion technique results in tracking performance similar to the current state-of-the-art but with worse scaling complexity in time. To solve this problem, we also present an implementation as quantum algorithm, using the Harrow-Hassadim-Lloyd (HHL) algorithm: this approach can potentially provide an exponential speedup as a function of the number of input hits over its classical counterpart, in spite of limitations due to the well-known HHL Hamiltonian simulation and readout problems. The findings presented in this paper shed light on the potential of leveraging quantum computing for real-time particle track reconstruction in high-energy physics.

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Davide Nicotra, Miriam Lucio Martinez, Jacco Andreas de Vries, Marcel Merk, Kurt Driessens, Ronald Leonard Westra, Domenica Dibenedetto, Daniel Hugo Cámpora Pérez. 2023-08-01. A quantum algorithm for track reconstruction in the LHCb vertex detector. https://doi.org/10.1088/1748-0221%2F18%2F11%2Fp11028

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