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Sestini, Lorenzo (2016) Search for a Higgs boson decaying to a pair of b quarks in the forward region of pp collisions with the LHCb detector. [Ph.D. thesis]

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Abstract (english)

LHCb is a forward spectrometer (pseudorapidity coverage 2 < eta < 5) designed for heavy flavour physics, located at the Large Hadron Collider (LHC). Thanks to its unique features LHCb is able to perform electroweak and jets measurements in a complementary phase space with respect to the General Purpose Detectors (GPD) at LHC, ATLAS and CMS.
In this thesis techniques to identify and reconstruct b b-bar resonances with the LHCb detector are developed.
First the data collected by LHCb during the Run I data taking are analyzed to identify the Z -> b b-bar decay, to measure its cross section and to determine the jet energy scale.
Then the dataset is used to set experimental limit on the Standard Model (SM) H -> b bar-b production in the forward region.

Abstract (italian)

LHCb è uno spettrometro collocato nella regione in avanti delle collisioni p-p al Large Hadron Collider (pseudorapidità coperta 2 < eta < 5) progettato per la fisica dei quark b e c. Grazie alle sue uniche caratteristiche LHCb può effettuare misure di fisica elettrodebole e dei jet in uno spazio delle fasi complementare ai General Purpose detectors (GPD) ad LHC, ATLAS e CMS.
In questa tesi sono sviluppate tecniche per identificare e ricostruire risonanze b b-bar con il rivelatore LHCb.
I dati raccolti nel periodo Run I sono analizzati per identificare il decadimentto Z -> b b-bar, per misurare la sezione d'urto di questo processo e per determinare la scala di energia dei jet.
Successivamente il campione viene utilizzato per stabilire il limite superiore sulla produzione di H-> b b-bar nella regione in avanti.

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EPrint type:Ph.D. thesis
Tutor:Lucchesi, Donatella
Ph.D. course:Ciclo 29 > Corsi 29 > FISICA
Data di deposito della tesi:31 January 2017
Anno di Pubblicazione:31 January 2016
Key Words:higgs - heavy quarks - jets - electroweak - LHCb
Settori scientifico-disciplinari MIUR:Area 02 - Scienze fisiche > FIS/04 Fisica nucleare e subnucleare
Struttura di riferimento:Dipartimenti > Dipartimento di Fisica e Astronomia "Galileo Galilei"
Codice ID:10161
Depositato il:02 Nov 2017 15:13
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