25–29 May 2026
Chulalongkorn University
Asia/Bangkok timezone

Simulation Studies of a Brute-Force χ² Alignment Framework for the CBM Silicon Tracking System

28 May 2026, 15:15
1h
Sala Phra Kieo, Second Floor

Sala Phra Kieo, Second Floor

Board: 320-Th
Poster Presentation Track 3 - Offline data processing Poster

Speaker

Nora Bluhme (Goethe University Frankfurt (DE))

Description

The Compressed Baryonic Matter (CBM) experiment at the upcoming Facility for Antiproton and Ion Research (FAIR) will investigate heavy-ion collisions at interaction rates of up to $10^7\, \text{s}^{-1}$.

To fully exploit the intrinsic precision of the tracking detectors, an accurate alignment of all sensor elements is essential. Track-based software alignment determines small but critical translations and rotations of detector components with respect to their nominal geometry. This is commonly achieved by minimising a global χ² constructed from high-quality tracks.
In addition to established alignment methods, we are developing a complementary brute-force χ² minimisation approach. This method eliminates the need for extensive analytical treatment of the cost function and allows for an independent handling of individual alignment parameters. Furthermore, it enables the straightforward inclusion of diverse constraint types, including non-linear and inequality constraints.
In this contribution, we present recent results obtained with this framework using simulated data for the CBM Silicon Tracking System (STS). We study the recovery of artificially introduced shifts and rotations of detector components at different hierarchical levels of the geometry. The method’s performance, stability are evaluated, and the requirements for sufficiently constraining the alignment problem are discussed.

This work is supported by BMFTR (05P24RF3).

Author

Nora Bluhme (Goethe University Frankfurt (DE))

Co-authors

Sergey Gorbunov (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE)) Volker Lindenstruth (Goethe University Frankfurt (DE))

Presentation materials