No Arabic abstract
If the Higgs is produced with a large enough cross section in the {em exclusive} reaction $p + bar{p} to p + H + bar{p}$ it will give rise to a peak at $M_H$ in the {em missing mass} ($MM$) spectrum, calculated from the 4-momenta of the beam particles and the outgoing $p$ and $bar{p}$. The resolution in $MM$ can be approximately 250 MeV, independent of $M_H$ from 100 GeV to 200 GeV. This high resolution makes a search feasible over nearly this full mass range at the Tevatron with 15 fb$^{-1}$ as hoped for in Run II.
I report on a calculation of the inclusive Higgs boson production cross section at hadron colliders at next-to-next-to-leading order in QCD. The result is computed as an expansion about the threshold region. By continuing the expansion to very high order, we map the result onto basis functions and obtain the result in closed analytic form.
We discuss the prospects for measuring the W mass in Run II of the Tevatron and at the LHC. The basic techniques used to measure M_W are described and the statistical, theoretical and detector-related uncertainties are discussed in detail.
We present the Higgs boson production cross section at Hadron colliders in the gluon fusion production mode through N3LO in perturbative QCD. Specifically, we work in an effective theory where the top quark is assumed to be infinitely heavy and all other quarks are considered to be massless. Our result is the first exact formula for a partonic hadron collider cross section at N3LO in perturbative QCD. Furthermore, this result represents the first analytic computation of a hadron collider cross section involving elliptic integrals. We derive numerical predictions for the Higgs boson cross section at the LHC. Previously this result was approximated by an expansion of the cross section around the production threshold of the Higgs boson and we compare our findings. Finally, we study the impact of our new result on the state of the art prediction for the Higgs boson cross section at the LHC.
We explore the collider relevance of a charge-radius coupling of the composite Higgs boson. This coupling offers a deep probe of the composite nature of the Higgs mechanism, being sensitive to the electromagnetic and weak isospin structure of its constituents. The main collider effect consists in the production of the Higgs boson in association with a light composite pseudo-scalar. We present an exploratory cut-and-count analysis at hadron colliders, like the LHC, showing that an efficient background suppression can be achieved. More sophisticated techniques, however, are necessary to select a sufficient number of signal events, due to the small production rates. This justifies further investigation of this channel, which is highly complementary to other searches for compositeness in the Higgs sector.
The search for Higgs bosons and extensions of the Standard Model of Elementary Particle Physics are main tasks of the Large Hadron Collider (LHC) at CERN which will start operation mid-2008. In this thesis processes which can be used to detect supersymmetric Higgs bosons at the LHC were considered. First a computer program was written which completes the toolbox for automatic calculations of hadronic cross sections. Using this program, the supersymmetric QCD corrections to associated H-W+-production and h0-production via vector-boson fusion and in association with heavy quarks were calculated. The corrections partly give significant contributions to the total cross section. Additionally, the possibility to measure the quartic Higgs self-coupling via triple-Higgs production was investigated and found to be challenging.