# Quark Matter 2014 - XXIV International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

19-24 May 2014
Europe/Zurich timezone

## Global alignment methods of the inner silicon tracker (HFT) of the STAR experiment at RHIC

20 May 2014, 16:30
2h

### spectrum

Board: M-13
Poster Future Experimental Facilities, Upgrades, and Instrumentation

### Speaker

Mr Michael Lomnitz (Kent State University)

### Description

We present an overview of two global alignment procedures developed for the Heavy Flavor Tracker[1] (HFT), the new silicon upgrade detector of STAR experiment at RHIC. Both methods are iterative minimization techniques and use as input the hit residual information from primary tracks reconstructed by the STAR TPC. One relies on a factorization of the alignment steps and uses histogramming techniques to improve the robustness of the minimization, while the other is based on a global $\chi^2$ minimization technique developed for the CMS detector[2]. The methods’ performance was extensively tested using simulations with mis-alignments. Here we present the basic elements of the methods, their estimated performance characteristics and also their application to data collected from a PIXEL prototype beam test in 2013. [1]:HFT proposal: http://rnc.lbl.gov/~wieman/hft_final_submission_version.pdf [2]:The HIP algorithm for track based alignment and its application to the CMS detector, V. Karimaki et. al., CMS note 2006/018
On behalf of collaboration: STAR

### Primary author

Mr Michael Lomnitz (Kent State University)

### Co-authors

Mr Amilkar Quintero (Kent State University) Dr Flemming Videbaek (Brookhaven National Lab) Dr Hao Qiu (Lawrence Berkeley National Lab) Dr Jonathan Bouchet (Kent State University) Mr Long Ma (Lawrence Berkeley National Lab, Shanghai Institute of Applied Physic) Prof. Spiros Margetis (Kent State University) Dr Xin Dong (Lawrence Berkeley National Lab)

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