Acharya, S.; Adamová, D.; Adler, A.; Aglieri Rinella, Rinella; Agnello, M. & Agrawal, N.
[Vis alle 1 030 forfattere av denne artikkelen](2024).
Measurement of the radius dependence of charged-particle jet suppression in Pb–Pb collisions at s<inf>NN</inf>=5.02TeV.
Physics Letters B.
ISSN 0370-2693.
849.
doi: 10.1016/j.physletb.2023.138412.
We propose a novel technique for reconstructing charged particles in digital tracking calorimeters using reinforcement learning aiming to benefit from the rapid progress and success of neural network architectures without the dependency on simulated or manually-labeled data. Here we optimize by trial-and-error a behavior policy acting as an approximation to the full combinatorial optimization problem, maximizing the physical plausibility of sampled trajectories. In modern processing pipelines used in high energy physics and related applications, tracking plays an essential role allowing to identify and follow charged particle trajectories traversing particle detectors. Due to the high multiplicity of charged particles and their physical interactions, randomly deflecting the particles, the reconstruction is a challenging undertaking, requiring fast, accurate and robust algorithms. Our approach works on graph-structured data, capturing track hypotheses through edge connections between particles in the detector layers. We demonstrate in a comprehensive study on simulated data for a particle detector used for proton computed tomography, the high potential as well as the competitiveness of our approach compared to a heuristic search algorithm and a model trained on ground truth. Finally, we point out limitations of our approach, guiding towards a robust foundation for further development of reinforcement learning based tracking.
Schilling, Alexander; Aehle, Max; Alme, Johan; Barnaföldi, Gergely Gábor; Bodova, Tea & Borshchov, Vyacheslav
[Vis alle 46 forfattere av denne artikkelen](2023).
Uncertainty-aware spot rejection rate as quality metric for proton therapy using a digital tracking calorimeter.
Physics in Medicine and Biology.
ISSN 0031-9155.
68(19).
doi: 10.1088/1361-6560/acf5c2.
Fulltekst i vitenarkiv
The azimuthal (ϕ) correlation distributions between heavy-flavor decay electrons and associated charged particles are measured in pp and p–Pb collisions at √sNN = 5.02 TeV. Results are reported for electrons with transverse momentum 4 < pT < 16 GeV/c and pseudorapidity |η| < 0.6. The associated charged particles are selected with transverse momentum 1 < pT < 7 GeV/c, and relative pseudorapidity separation with the leading electron |η| < 1. The correlation measurements are performed to study and characterize the fragmentation and hadronization of heavy quarks. The correlation structures are fitted with a constant and two von Mises functions to obtain the baseline and the near- and away-side peaks, respectively. The results from p– Pb collisions are compared with those from pp collisions to study the effects of cold nuclear matter. In the measured trigger electron and associated particle kinematic regions, the two collision systems give consistent results. The ϕ distribution and the peak observables in pp and p–Pb collisions are compared with calculations from various Monte Carlo event generators.
The production of prompt + c baryons at midrapidity (|y| < 0.5) was measured in central (0–10%) and mid-central (30–50%) Pb–Pb collisions at the center-of-mass energy per nucleon–nucleon pair √sNN = 5.02 TeV with the ALICE detector. The results are more precise, more differential in centrality, and reach much lower transverse momentum (pT = 1 GeV/c) with respect to previous measurements performed by the ALICE, STAR, and CMS Collaborations in nucleus–nucleus collisions, allowing for an extrapolation down to pT = 0. The pT-differential + c /D0 ratio is enhanced with respect to the pp measurement for 4 < pT < 8 GeV/c by 3.7 standard deviations (σ), while the pT-integrated ratios are compatible within 1σ. The observed trend is similar to that observed in the strange sector for the /K0 S ratio. Model calculations including coalescence or statistical hadronization for charm-hadron formation are compared with the data.
Acharya, Shreyasi; Adamová, Dagmar; Adler, Alexander; Adolfsson, Jonatan; Aglieri Rinella, Gianluca & Agnello, Michelangelo
[Vis alle 52 forfattere av denne artikkelen](2022).
Characterizing the initial conditions of heavy-ion collisions at the LHC with mean transverse momentum and anisotropic flow correlations.
Physics Letters B.
ISSN 0370-2693.
834,
s. 1–11.
doi: 10.1016/j.physletb.2022.137393.
Fulltekst i vitenarkiv
Acharya, Shreyasi; Adamová, Dagmar; Adler, Alexander; Adolfsson, Jonatan; Aglieri Rinella, Gianluca & Agnello, Michelangelo
[Vis alle 51 forfattere av denne artikkelen](2022).
Charm-quark fragmentation fractions and production cross section at midrapidity in pp collisions at the LHC.
Physical Review D.
ISSN 2470-0010.
105:L011103,
s. 1–14.
doi: 10.1103/PhysRevD.105.L011103.
Fulltekst i vitenarkiv
Acharya, Shreyasi; Adamová, Dagmar; Adler, Alexander; Adolfsson, Jonatan; Aglieri Rinella, Gianluca & Agnello, Michelangelo
[Vis alle 51 forfattere av denne artikkelen](2022).
Nuclear modification factor of light neutral-meson spectra up to high
transverse momentum in p–Pb collisions at √sNN = 8.16 TeV.
Physics Letters B.
ISSN 0370-2693.
827:136943,
s. 1–12.
doi: 10.1016/j.physletb.2022.136943.
Fulltekst i vitenarkiv
Acharya, Shreyasi; Adamová, Dagmar; Adler, Alexander; Adolfsson, Jonatan; Aglieri Rinella, Gianluca & Agnello, Michelangelo
[Vis alle 51 forfattere av denne artikkelen](2022).
Measurement of prompt D+
s -meson production and azimuthal
anisotropy in Pb–Pb collisions at √sNN = 5.02 TeV
.
Physics Letters B.
ISSN 0370-2693.
827:136986,
s. 1–17.
doi: 10.1016/j.physletb.2022.136986.
Fulltekst i vitenarkiv
Acharya, Shreyasi; Adamová, Dagmar; Adler, Alexander; Adolfsson, Jonatan; Aglieri Rinella, Gianluca & Agnello, Michelangelo
[Vis alle 51 forfattere av denne artikkelen](2022).
Production of Λ and K0
S in jets in p–Pb collisions at √sNN = 5.02 TeV
and pp collisions at √s = 7 TeV.
Physics Letters B.
ISSN 0370-2693.
827:136984,
s. 1–15.
doi: 10.1016/j.physletb.2022.136984.
Fulltekst i vitenarkiv
Acharya, Shreyasi; Adamová, Dagmar; Adler, Alexander; Adolfsson, Jonatan; Aglieri Rinella, Gianluca & Agnello, Michelangelo
[Vis alle 51 forfattere av denne artikkelen](2022).
Measurement of the Groomed Jet Radius and Momentum Splitting Fraction in pp and Pb-Pb Collisions at √sNN=5.02 TeV.
Physical Review Letters.
ISSN 0031-9007.
128:102001,
s. 1–14.
doi: 10.1103/PhysRevLett.128.102001.
Fulltekst i vitenarkiv