Cross section normalization in proton-proton collisions at $\sqrt{s}$ = 2.76 TeV and 7 TeV, with ALICE at LHC

TL;DR

This paper reports on the measurement of reference process cross sections in proton-proton collisions at 2.76 TeV and 7 TeV using ALICE at LHC, emphasizing instrumental and technical aspects and ensuring consistency with other experiments.

Contribution

It provides the first detailed cross section measurements for reference processes at these energies with systematic uncertainty analysis and instrumental calibration.

Findings

Cross sections at 2.76 TeV and 7 TeV are measured with systematic uncertainties.

Consistency with other LHC experiments is confirmed.

Instrumental and technical methods for beam property extraction are detailed.

Abstract

Measurements of the cross sections of the reference processes seen by the ALICE trigger system were obtained based on beam properties measured from van der Meer scans. The measurements are essential for absolute cross section determinations of physics processes. The paper focuses on instrumental and technical aspects of detectors and accelerators, including a description of the extraction of beam properties from the van der Meer scan. As a result, cross sections of reference processes seen by the ALICE trigger system are given for proton-proton collisions at two energies; $\sqrt{s}$=2.76 TeV and 7 TeV, together with systematic uncertainties originating from beam intensity measurements and other detector effects. Consistency checks were performed by comparing to data from other experiments in LHC.