Measurement of identified charged hadron spectra with the ALICE experiment at the LHC

TL;DR

This paper reports on the measurement of charged hadron transverse momentum spectra in proton-proton collisions at 900 GeV using the ALICE detector, employing multiple identification methods to cover a broad momentum range.

Contribution

It presents a comprehensive methodology combining various particle identification techniques in ALICE to measure identified charged hadron spectra at low to intermediate transverse momenta.

Findings

Charged hadron spectra measured from 100 MeV/c to 2.5 GeV/c.

Comparison with theoretical models and previous data included.

Identification of strange mesons and baryons via decay topology.

Abstract

The ALICE experiment features multiple particle identification systems. The measurement of the identified charged hadron $p_{t}$ spectra in proton-proton collisions at $\sqrt{s}=900$ GeV will be discussed. In the central rapidity region ($|\eta|<0.9$) particle identification and tracking are performed using the Inner Tracking System (ITS), which is the closest detector to the beam axis, the Time Projection Chamber (TPC) and a dedicated time-of-flight system (TOF). Particles are mainly identified using the energy loss signal in the ITS and TPC. In addition, the information from TOF is used to identify hadrons at higher momenta. Finally, the kink topology of the weak decay of charged kaons provides an alternative method to extract the transverse momentum spectra of charged kaons. This combination allows to track and identify charged hadrons in the transverse momentum ($p_{t}$) range from 100 MeV/c up to 2.5 GeV/$c$. Mesons containing strange quarks (\kos, $\phi$) and both singly and doubly strange baryons (\lam, \lambar, and \xip + \xim) are identified by their decay topology inside the TPC detector. Results obtained with the various identification tools above described and a comparison with theoretical models and previously published data will be presented.