Data Quality Assurance (QA) is an important aspect of every High-Energy Physics experiment, especially in the case of the ALICE experiment at the Large Hadron Collider (LHC) whose detectors are extremely sophisticated and complex devices. To avoid processing low quality or redundant data, and to classify it for analysis, human experts are currently involved in an offline assessment of the...
In the track reconstruction in the CMS software, particle tracks are determined using a Combinatorial Track Finder algorithm. In order to optimize the speed and accuracy of the algorithm, the tracks are reconstructed using an iterative process: Easiest tracks are searched first, then hits, associated to good found tracks, are excluded from consideration in the following iterations (masking)...
During the LHC Run III, starting in 2020, the instantaneous luminosity of LHCb will be increased up to $2\times10^{33}$ cm$^{-2}$ s$^{-1}$, five times larger than in Run II. The LHCb detector will then have to be upgraded in 2019. In fact, a full software event reconstruction will be performed at the full bunch crossing rate by the trigger, in order to profit of the higher instantaneous...
The alignment of the ATLAS Inner Detector is performed with a track-based alignment algorithm.
Its goal is to provide an accurate description of the detector geometry such
that track parameters are accurately determined and free from biases.
Its software implementation is modular and configurable,
with a clear separation of the alignment algorithm from the detector system specifics and the...
Machine learning in high energy physics relies heavily on simulation for fully supervised training. This often results in sub-optimal classification when ultimately applied to (unlabeled) data. At CTD2017, we showed how to avoid this problem by training directly on data using as input the fraction of signal and background in each training sample. We now have a new method that does not even...
Background
Proton CT is a prototype imaging modality for the reconstruction of the Proton Stopping Power inside a patient for more accurate calculations of the dose distributions in proton therapy treatment dose planplanning systems. A prototype proton CT system, called the Digital Tracking Calorimeter (DTC) is currectly under development where aluminum energy absorbers are sandwiched...
The High Luminosity LHC (HL-LHC) plans to increase the LHC dataset by an order of magnitude, increasing the potential for new physics discoveries. The HL-LHC upgrade, planned for 2025 will increase the peak luminosity to 7.5×10^34cm^-2s^-1, corresponding to ~200 inelastic proton-proton collisions per beam crossing. To mitigate the increased radiation doses and pileup, the ATLAS Inner Detector...
With the planned addition of the tracking information in the Level 1 trigger in CMS for the HL-LHC, the algorithms for Level 1 trigger can be completely reconceptualized. Following the example for offline reconstruction in CMS to use complementary subsystem information and mitigate pileup, we explore the feasibility of using Particle Flow-like and pileup per particle identification techniques...
Silicon tracking detectors can record the charge in each channel (analog or digitized) or have only binary readout (hit or no hit). While there is significant literature on the position resolution obtained from interpolation of charge measurements, a comprehensive study of the resolution obtainable with binary readout is lacking. It is commonly assumed that the binary resolution is...
The pixel detectors for the High Luminosity upgrades of the ATLAS and CMS detectors will preserve digitized charge information in spite of extremely high hit rates. Both circuit physical size and output bandwidth will limit the number of bits to which charge can be digitized and stored. We therefore study the effect of the number of bits used for digitization and storage on single and...
Tracking in high density environments, particularly in high energy jets, plays an important role in many physics analyses at the LHC. In such environments, there is significant degradation of track reconstruction performance. Between runs 1 and 2, ATLAS implemented an algorithm that splits pixel clusters originating from multiple charged particles, using charge information, resulting in the...
In order to overcome the difficulty brought by the curling charged tracks in the BESIII drift chamber, we introduce the Hough transform based tracking method, which is used as a supplementary to find low transverse momentum tracks. This tracking algorithm is realized in the BESIII offline software system and its performance has been checked by both Monte Carlo and data. The results show that...
The reconstruction of multi-turn curling tracks on COMET Phase-I drift chamber is a challenge. A method of Deterministic Annealing Filter and implements a global competition between hits from different turn tracks is introduced. This method assigns the detector measurements to the track assumption based on the weighted mean of fitting quality on different turns. Studied have been done on the...
In the CDR study of the CEPC project, tracking algorithms and their performances are important task. For considering different design of tracker system, we are implementing corresponding tracking algorithms. Currently, we apply existing Clupatra as tracking for TPC, and also are exploiting ArborTracking at the same time. We attempt to use existing ConformalTracking as tracking for the design...
Recently we showed that deep learning can be used for model parameter estimation for strong gravitational lensing systems. Here we demonstrate a method for obtaining the uncertainties of these parameters. We use variational inference to obtain approximate posteriors of Bayesian neural networks and apply it to a network trained to estimate the parameters of the Singular Isothermal Ellipsoid...
