Low-x QCD with jets in the CMD hadron forward calorimeter in proton-proton collisions at = 14 TeV and test studies of forward calorimeters

Forward (di)jet measurements are a useful tool to constrain the low-x Parton DistributionFunctions (PDFs) and to study the possible onset of BFKL and/or gluon saturationQCD evolutions in the proton. This study presents detailed studies of the jet reconstructioncapabilities in the Hadron Forward (HF) calorimeter (3< | ? | 5) in the CMS experiment.Also, it compares the performances (response, energy and position resolutions) of variousalgorithms: SISCone (R = 0_5), Iterative Cone (R = _ 0_5) and fast-kT (D = _ 0_4), forjets of relatively low transverse momentum pT ? 20 - 100 GeV/c. The expected sensitivityof the single inclusive forward jet pT spectrum to the underlying PDFs, as well asthe azimuthal decorrelation of jets with a large rapidity separation (Mueller-Navelet dijets)will be presented for p-p collisions at = 14 TeV assuming an integrated luminosity of L dt = 1 pb -1 for this analysis.In this thesis also radiation hardness measurements of HF _bers irradiated with 24 GeVprotons up to 1.25 Grad and the performance studies of the second prototype of the CASTOR(Centauro And Strange Object Research) calorimeter with 2004 test beams are presentedin detail.