SearcharxivSearch

arXiv · 2508.07846

Introducing a Markov Chain-Based Time Calibration Procedure for Multi-Channel Particle Detectors: Application to the SuperFGD and ToF Detectors of the T2K Experiment

Abstract

Inter-channel mis-synchronisation can be a limiting factor to the time resolution of high performance timing detectors with multiple readout channels and independent electronics units. In these systems, time calibration methods employed must be able to efficiently correct for minimal mis-synchronisation between channels and achieve the best detector performance. We present an iterative time calibration method based on Markov Chains, suitable for detector systems with multiple readout channels. Starting from correlated hit pairs alone, and without requiring an external reference time measurement, the method solves for fixed per-channel offsets, with precision limited only by the intrinsic single-channel resolution. A mathematical proof that the method is able to find the correct time offsets to be assigned to each detector channel in order to achieve inter-channel synchronisation is given, and it is shown that the number of iterations to reach convergence within the desired precision is controllable with a single parameter. Numerical studies are used to confirm unbiased recovery of true offsets. Finally, the application of the calibration method to the Super Fine-Grained Detector (SuperFGD) and the Time of Flight (TOF) detector at the upgraded T2K near detector (ND280) shows good improvement in overall timing resolution, demonstrating the effectiveness in a real-world scenario and scalability.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

S. Abe, H. Alarakia-Charles, I. Alekseev, C. Alt, T. Arai, T. Arihara, S. Arimoto, A. M. Artikov, Y. Awataguchi, N. Babu, V. Baranov, G. Barr, D. Barrow, L. Bartoszek, L. Bernardi, L. Berns, S. Bhattacharjee, A. V. Boikov, A. Blanchet, A. Blondel, A. Bonnemaison, S. Bordoni, M. H. Bui, T. H. Bui, F. Cadoux, S. Cap, A. Cauchois, J. Chakrani, P. S. Chong, A. Chvirova, P. Collard, M. Danilov, C. Davis, V. Davouloury, Yu. I. Davydov, A. Dergacheva, C. Domangue, D. Douqa, T. A. Doyle, O. Drapier, A. Eguchi, J. Elias, G. Erofeev, Y. Favre, D. Fedorova, S. Fedotov, D. Ferlewicz, Y. Fujii, R. Fujita, Y. Furui, F. Gastaldi, A. Gendotti, A. Germer, L. Giannessi, C. Giganti, V. Glagolev, R. Guillaumat, G. Ha, N. C. Hastings, I. Heitkamp, J. Hu, C. Husi, A. K. Ichikawa, T. H. Ishida, A. Izmaylov, K. Iwamoto, M. Jakkapu, C. Jesús-Valls, J. Y. Ji, P. Jonsson, C. K. Jung, H. Kakuno, V. S. Kasturi, M. Kawaue, P. T. Keener, M. Khabibullin, N. V. Khomutov, A. Khotjantsev, T. Kikawa, H. Kikutani, N. V. Kirichkov, A. Klustová, H. Kobayashi, T. Kobayashi, L. Koch, S. Kodama, A. O. Kolesnikov, M. Kolupanova, A. Korzenev, T. Koto, Y. Kudenko, S. Kuribayashi, T. Kutter, M. Lachat, K. Lachner, M. Lamers James, D. Last, N. Latham, M. Lawe, T. A. Le. 2025-08-11. Introducing a Markov Chain-Based Time Calibration Procedure for Multi-Channel Particle Detectors: Application to the SuperFGD and ToF Detectors of the T2K Experiment. https://doi.org/10.1088/1748-0221%2F20%2F10%2Fp10030

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

High-Speed Semi-FE Readout Module for ATLAS MDT at HL-LHC: Design and Production-Level Characterization

The High-Luminosity upgrade of the Large Hadron Collider (HL-LHC) introduces increased demands on the ATLAS Muon Spectrometer, particularly in terms of data throughput, timing distribution and system reliability. The Phase-II Chamber Service Module (CSM) is a key component of the upgraded Monitored Drift Tube (MDT) trigger and readout system, providing a high-speed interface between the front-end electronics and the backend systems. This paper describes the design and implementation of the Phase-II CSM, together with its validation. The results show that the CSM supports two independent optical uplinks, each operating at a line rate of 10.24 Gbps, together with clock distribution and slow control in the expected operating environment. Integration with small-diameter MDT (sMDT) chambers and tests with the prototype L0MDT trigger system are also presented. The CSM boards are now in production and will be used for installation and integration during the upcoming LHC Long Shutdown.

physics.ins-det

Spectral Discrimination of Deposited Gamma-Ray Energies in a Simulated CeBr$_3$ Scintillator

We show that wavelength measurements of individual detected optical photons may provide additional information about gamma-ray energy deposited in a CeBr$_3$ crystal when the detected-photon-count distributions overlap for nearby gamma-ray energies. Monoenergetic 662 and 629 keV gammas are used in a Geant4 simulation of a $25\times25\times20~\mathrm{mm^3}$ CeBr$_3$ crystal. Assuming a light yield of $6.0\times10^4$ photons/MeV, a wavelength-independent photon-detection efficiency of 30%, and a wavelength resolution of $\sigma_{\lambda}=40$ nm, we find that the fraction of photons reconstructed above 385 nm gives an event-level separation of $\sim$ 2 standard deviations between the 662 and 629 keV event populations selected within the same $\sim$ 1%-wide detected-photon-count interval. No timing or reconstructed interaction-position information is used. The result demonstrates, within the present simulation model, that event-dependent optical spectra can retain energy information beyond an undifferentiated photon count.

physics.ins-det

Operation of a negative ion gas time projection chamber without electronegative fill gases

The high fidelity reconstruction of particle tracks in micropatterned gaseous time projection chambers renders this technology ideal for future rare-event searches, including direction-sensitive dark matter experiments. Large drift distances are typically required for such experiments, so that the overall spatial resolution is limited by diffusion. Negative ion drift exhibits lower diffusion than electron drift and is thus an attractive option for realising a large-scale detector. The use of electronegative gases to create negative ions introduces technical challenges, most notably a reduction in gain when compared to conventional gas mixtures. In this study, we demonstrate a new method for negative ion generation via dissociative electron attachment using the conventional molecular fill gas CF$_4$. Our optical measurements of negative ion drift indicate electron attachment lengths of $<$1 mm and comparable gain to electron avalanches. The individual negative ion avalanches were also time-resolved, allowing the number of ions reaching the readout to be counted. We measure an improved energy resolution by single ion counting, relative to an integrated electron avalanche signal measured under identical gain conditions.

physics.ins-det