arXiv subjects

Mathieu Rubin

Publications and source records attributed to Mathieu Rubin.

7 recordsLinked to original sources

arXiv2010

Giant QCD K-factors beyond NLO

Hadronic observables in Z+jet events can be subject to large NLO corrections at TeV scales, with K-factors that even reach values of order 50 in some cases. We develop a method, LoopSim, by which approximate NNLO predictions can be obtained for such observables, supplementing NLO Z+jet and NLO Z+2-jet results with a unitarity-based approximation for missing higher loop terms. We first test the method against known NNLO results for Drell-Yan lepton pt spectra. We then show our approximate NNLO results for the Z+jet observables. Finally we examine whether the LoopSim method can provide useful information even in cases without giant K-factors, with results for observables in dijet events that can be compared to early LHC data.

hep-ph↗

arXiv2010

Non-Global Logarithms in Filtered Jet Algorithms

We analytically and numerically study the effect of perturbative gluons emission on the "Filtering analysis", which is part of a subjet analysis procedure proposed two years ago to possibly identify a low-mass Higgs boson decaying into b\bar{b} at the LHC. This leads us to examine the non-global structure of the resulting perturbative series in the leading single-log large-N_c approximation, including all-orders numerical results, simple analytical approximations to them and comments on the structure of their series expansion. We then use these results to semi-analytically optimize the parameters of the Filtering analysis so as to suppress as much as possible the effect of underlying event and pile-up on the Higgs mass peak reconstruction while keeping the major part of the perturbative radiation from the b\bar{b} dipole.

hep-ph↗

arXiv2009

Light Higgs searches at the LHC using jet substructure

It is widely believed that searching for a light Higgs boson (with a mass around 120 GeV) in the WH and ZH channels, where H decays into $b\bar{b}$, will be very challenging at the LHC. These proceedings describe how this channel can be recovered as a promising search channel at high $p_t$ by using a subjet analysis procedure.

hep-ph↗

arXiv2008

Jet substructure as a new Higgs search channel at the Large Hadron Collider

We show that W H and Z H production where the Higgs boson decays to bbbar can be recovered as good search channels for the Standard Model Higgs at the Large Hadron Collider. This is done by requiring the Higgs to have high transverse momentum, and employing state-of-the-art jet reconstruction and decomposition techniques.

hep-ph↗

arXiv2008

Jet substructure as a new Higgs search channel at the LHC

These proceedings discuss a possible new search strategy for a light Higgs boson at the LHC, in high-pt WH and ZH production where the Higgs boson decays to a single collimated b-bbar jet. Material is included that is complementary to what was shown in the original article, arXiv:0802.2470.

hep-ph↗

arXiv2008

Jet substructure as a new Higgs search channel at the LHC

It is widely considered that, for Higgs boson searches at the Large Hadron Collider, WH and ZH production where the Higgs boson decays to b anti-b are poor search channels due to large backgrounds. We show that at high transverse momenta, employing state-of-the-art jet reconstruction and decomposition techniques, these processes can be recovered as promising search channels for the standard model Higgs boson around 120 GeV in mass.

hep-ph↗

arXiv2007

Resonant eigenstates in quantum chaotic scattering

We study the spectrum of quantized open maps, as a model for the resonance spectrum of quantum scattering systems. We are particularly interested in open maps admitting a fractal repeller. Using the ``open baker's map'' as an example, we numerically investigate the exponent appearing in the Fractal Weyl law for the density of resonances; we show that this exponent is not related with the ``information dimension'', but rather the Hausdorff dimension of the repeller. We then consider the semiclassical measures associated with the eigenstates: we prove that these measures are conditionally invariant with respect to the classical dynamics. We then address the problem of classifying semiclassical measures among conditionally invariant ones. For a solvable model, the ``Walsh-quantized'' open baker's map, we manage to exhibit a family of semiclassical measures with simple self-similar properties.

nlin.CD↗