uu.seUppsala universitets publikasjoner
Endre søk

Referera
Referensformat
• apa
• ieee
• modern-language-association
• vancouver
• Annet format
Fler format
Språk
• de-DE
• en-GB
• en-US
• fi-FI
• nn-NO
• nn-NB
• sv-SE
• Annet språk
Fler språk
Utmatningsformat
• html
• text
• asciidoc
• rtf
Phenomenology of Charged Higgs Bosons and B-meson Decays
Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Kärn- och partikelfysik.
2009 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
##### Abstract [en]

For more than 30 years the Standard Model has been the theoretical foundation for particle physics. The theory has been veriﬁed successfully by experimental tests. Its biggest shortcoming is the non-discovery of the Higgs boson,responsible for giving the other particles masses. Despite its success there are hints that the Standard Model is not the complete theory and many extensions of it, such as supersymmetry, have been proposed.

Extended theories often predict the existence of a charged Higgs boson and its detection will be a clear sign of physics beyond the Standard Model. The main focus in this thesis is on various phenomenological aspects of the charged Higgs boson. For favorable mass and couplings direct detection is shown to be possible at the Large Hadron Collider in production with an associated W boson. It is also shown how a light charged Higgs can have measurable effects on spin correlations in decays of pair-produced top quarks. The charged Higgs boson can also be seen indirectly, in for example B-meson decays, which can be used to put constraints on its mass and fermion couplings. Exclusion limits in two supersymmetric models are given together with a comparison with the discovery potentials for the LHC experiments. A tool for calculating properties, such as masses and decays, of both charged and neutral Higgs bosons in the Two-Higgs-Doublet Model is also presented.

B-meson decays can also be used to test aspects of the strong interaction. Part of this thesis deals with improving and applying phenomenological models to B-meson decays. Although these models are not derived from ﬁrst principles, their success shows that they capture important features of non-perturbative strong interactions.

##### sted, utgiver, år, opplag, sider
Uppsala: Acta Universitatis Upsaliensis , 2009. , s. 40
##### Serie
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 606
##### Emneord [en]
Supersymmetry, Beyond Standard Model, B-Physics, Charged Higgs Boson, LHC, QCD, Spin Correlations, CMSSM, NUHM
##### Identifikatorer
ISBN: 978-91-554-7422-5 (tryckt)OAI: oai:DiVA.org:uu-9564DiVA, id: diva2:173287
##### Disputas
2009-03-20, Siegbahnsalen, Ånsgströmslaboratoriet, Lägerhyddsvägen 1, Uppsala, 13:15 (engelsk)
##### Veileder
Tilgjengelig fra: 2009-02-24 Laget: 2009-02-11 Sist oppdatert: 2010-12-09bibliografisk kontrollert
##### Delarbeid
1. Associated charged Higgs and W boson production in the MSSM at the CERN Large Hadron Collider
Åpne denne publikasjonen i ny fane eller vindu >>Associated charged Higgs and W boson production in the MSSM at the CERN Large Hadron Collider
2008 (engelsk)Inngår i: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 53, nr 2, s. 267-280Artikkel i tidsskrift (Fagfellevurdert) Published
##### Abstract [en]

We investigate the viability of observing charged Higgs bosons () produced in association with bosons at the CERN large hadron collider, using the leptonic decay and hadronic decay, within different scenarios of the minimal supersymmetric standard model (MSSM) with both real and complex parameters. Performing a parton level study we show how the irreducible standard model background from jets can be controlled by applying appropriate cuts and find that the size of a possible signal depends on the cuts needed to suppress QCD backgrounds and misidentifications. In the standard maximal mixing scenario of the MSSM we find a viable signal for large and intermediate masses () when using softer cuts (, 50 GeV), whereas for harder cuts (, 100 GeV) we only find a viable signal for very large (). We have also investigated a special class of MSSM scenarios with large mass splittings among the heavy Higgs bosons where the cross-section can be resonantly enhanced by factors up to one hundred, with a strong dependence on the -violating phases. Even so we find that the signal after cuts remains small except for small masses () when using the softer cuts. Finally, in all the scenarios we have investigated we have only found small -asymmetries.

##### Identifikatorer
urn:nbn:se:uu:diva-98098 (URN)10.1140/epjc/s10052-007-0453-x (DOI)000252299200007 ()
Tilgjengelig fra: 2009-02-11 Laget: 2009-02-11 Sist oppdatert: 2017-12-13bibliografisk kontrollert
2. PYBBWH: A program for associated charged Higgs and W boson production
Åpne denne publikasjonen i ny fane eller vindu >>PYBBWH: A program for associated charged Higgs and W boson production
(engelsk)Manuskript (Annet vitenskapelig)
##### Abstract [en]

The Monte Carlo program, PYBBWH, is an implementation of the associated production of a charged Higgs and a W boson from $b\bar b$ fusion in a general Two-Higgs-Doublet model for both CP-conserving and CP-violating couplings.It is implemented as a external process to Pythia 6.The code can be downloaded from http://www.isv.uu.se/thep/MC/pybbwh.

##### Identifikatorer
urn:nbn:se:uu:diva-98099 (URN)
Tilgjengelig fra: 2009-02-25 Laget: 2009-02-11 Sist oppdatert: 2010-01-14bibliografisk kontrollert
3. New angles on top quark decay to a charged Higgs
Åpne denne publikasjonen i ny fane eller vindu >>New angles on top quark decay to a charged Higgs
2009 (engelsk)Inngår i: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 01, nr 1, s. 024-Artikkel i tidsskrift (Fagfellevurdert) Published
##### Abstract [en]

To properly discover a charged Higgs Boson (H±) requires its spin and couplings to be determined. We investigate how to utilize t spin correlations to analyze the H± couplings in the decay tbH+bτ+ντ. Within the framework of a general Two-Higgs-Doublet Model, we obtain results on the spin analyzing coefficients for this decay and study in detail its spin phenomenology, focusing on the limits of large and small values for tan β. Using a Monte Carlo approach to simulate full hadron-level events, we evaluate systematically how the H± → τ±ντ decay mode can be used for spin analysis. The most promising observables are obtained from azimuthal angle correlations in the transverse rest frames of t(). This method is particularly useful for determining the coupling structure of H± in the large tan β limit, where differences from the SM are most significant.

##### Emneord
Beyond Standard Model, Higgs Physics, Spin and Polarization Effects, Hadronic Colliders
##### Identifikatorer
urn:nbn:se:uu:diva-98100 (URN)10.1088/1126-6708/2008/01/024 (DOI)000252983400053 ()
Tilgjengelig fra: 2009-02-11 Laget: 2009-02-11 Sist oppdatert: 2017-12-13bibliografisk kontrollert
4. Charged Higgs effects on top spin correlations
Åpne denne publikasjonen i ny fane eller vindu >>Charged Higgs effects on top spin correlations
2009 (engelsk)Inngår i: Proceedings of Science, ISSN 1824-8039, Vol. CHARGED2008, nr 024Artikkel i tidsskrift (Fagfellevurdert) Published
##### Identifikatorer
urn:nbn:se:uu:diva-98101 (URN)
Tilgjengelig fra: 2009-02-11 Laget: 2009-02-11 Sist oppdatert: 2009-06-17bibliografisk kontrollert
5. Charged Higgs bosons in minimal supersymmetry: updated constraints and experimental prospects
Åpne denne publikasjonen i ny fane eller vindu >>Charged Higgs bosons in minimal supersymmetry: updated constraints and experimental prospects
2008 (engelsk)Inngår i: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 11, nr 035Artikkel i tidsskrift (Fagfellevurdert) Published
##### Abstract [en]

We discuss the phenomenology of charged Higgs bosons in the MSSM with minimal flavor violation. In addition to the constrained MSSM (CMSSM) with universal soft supersymmetry breaking mass parameters at the GUT scale, we explore non-universal Higgs mass models (NUHM) where this universality condition is relaxed. To identify the allowed parameter space regions, we apply constraints from direct searches, low energy observables, and cosmology. We find that values of the charged Higgs mass as low as mH+ 135 GeV can be accommodated in the NUHM models, but that several flavor physics observables disfavor large H+ contributions, associated with high tan β, quite independently of MSSM scenario. We confront the constrained scenarios with the discovery potentials reported by ATLAS and CMS, and find that the current exclusion by indirect constraints is similar to the expected LHC discovery reach with 30 fb−1 of data. Finally, we evaluate the sensitivity of the presented discovery potential to the choice of MSSM benchmark scenario. This sensitivity is found to be higher in the case of a light (mH+ < mt) charged Higgs.

##### Emneord
Supersymmetric Standard Model, Higgs Physics, Hadronic Colliders
##### Identifikatorer
urn:nbn:se:uu:diva-98102 (URN)10.1088/1126-6708/2008/11/035 (DOI)000261315100035 ()
Tilgjengelig fra: 2009-02-11 Laget: 2009-02-11 Sist oppdatert: 2017-12-13bibliografisk kontrollert
6. Color rearrangements in B-meson decays
Åpne denne publikasjonen i ny fane eller vindu >>Color rearrangements in B-meson decays
2009 (engelsk)Inngår i: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 79, nr 1, s. 014011-Artikkel i tidsskrift (Fagfellevurdert) Published
##### Abstract [en]

Wepresent a new model, based on color rearrangements, which atthe same time can describe both hidden and open charmproduction in B-meson decays. The model is successfully compared toboth inclusive decays, such as B-->J/psiX and B-->DsX, as wellas exclusive ones, such as B-->J/psiK(*) and B-->D(*)D(*)K. It alsogives a good description of the momentum distribution of directJ/psi's, especially in the low-momentum region, which earlier has beenclaimed as a possible signal for new exotic states.

##### Identifikatorer
urn:nbn:se:uu:diva-98103 (URN)10.1103/PhysRevD.79.014011 (DOI)000262979700036 ()
Tilgjengelig fra: 2009-02-11 Laget: 2009-02-11 Sist oppdatert: 2017-12-13bibliografisk kontrollert
7. 2HDMC - two-Higgs-doublet model calculator
Åpne denne publikasjonen i ny fane eller vindu >>2HDMC - two-Higgs-doublet model calculator
2010 (engelsk)Inngår i: Computer Physics Communications, ISSN 0010-4655, E-ISSN 1879-2944, Vol. 181, nr 1, s. 189-205Artikkel i tidsskrift (Fagfellevurdert) Published
##### Abstract [en]

We describe the public C++ code 2HDMC which can be used to perform calculations in a general, CP-conserving, two-Higgs-doublet model (2HDM). The program features simple conversion between different parametrizations of the 2HDM potential, a flexible Yukawa sector specification with choices of different Z_2-symmetries or more general couplings, a decay library including all two-body - and some three-body - decay modes for the Higgs bosons, and the possibility to calculate observables of interest for constraining the 2HDM parameter space, as well as theoretical constraints from positivity and unitarity. The latest version of the 2HDMC code and full documentation is available from: http://www.isv.uu.se/thep/MC/2HDMC.

##### Emneord
Higgs physics, Two-Higgs-doublet model
##### Identifikatorer
urn:nbn:se:uu:diva-111157 (URN)10.1016/j.cpc.2009.09.011 (DOI)000273168600022 ()
Erratum in: Computer Physics Communications, 2010, vol. 181, issue 5, p. 985, doi: 10.1016/j.cpc.2009.12.026 Tilgjengelig fra: 2009-12-04 Laget: 2009-12-04 Sist oppdatert: 2017-12-12bibliografisk kontrollert

#### Open Access i DiVA

fulltekst(1033 kB)427 nedlastinger
##### Filinformasjon
Fil FULLTEXT01.pdfFilstørrelse 1033 kBChecksum SHA-512
4b97a9e54740722514e14ec6c956ff76d5ae4c6c9525cb256e77ef0d965beb7d0fc4af7a9c805a1295560ffb23a4e5b4ac89fc0a7b86116d475cacbea034205d
Type fulltextMimetype application/pdf
Kjøp publikasjonen >>

#### Søk utenfor DiVA

Totalt: 427 nedlastinger
Antall nedlastinger er summen av alle nedlastinger av alle fulltekster. Det kan for eksempel være tidligere versjoner som er ikke lenger tilgjengelige
isbn
urn-nbn

#### Altmetric

isbn
urn-nbn
Totalt: 1154 treff

Referera
Referensformat
• apa
• ieee
• modern-language-association
• vancouver
• Annet format
Fler format
Språk
• de-DE
• en-GB
• en-US
• fi-FI
• nn-NO
• nn-NB
• sv-SE
• Annet språk
Fler språk
Utmatningsformat
• html
• text
• asciidoc
• rtf