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A. Starodumov

Publications and source records attributed to A. Starodumov.

7 recordsLinked to original sources

Neutrino reconstruction with topological information

In general a decay with a missing (not detected) particle can not be fully reconstructed apart from a few exceptions. For example, if the momentum of the decaying particle is known or if the missing energy in an event is measured precisely, then the missing particle 4-momentum can be determined. Here a new method is proposed that utilizes additional information about the topology of a decay: The direction from the primary to the secondary vertex combined with momentum conservation allows the determination of the missing particle momentum up to a twofold ambiguity. The semileptonic decay of the Bs mesons is considered as an example to illustrate this method and to compare its performance against conventional approaches.

hep-ph

SM and MSSM Higgs Boson Production: Spectra at large transverse Momentum

Strategies for Higgs boson searches require the knowledge of the total production cross section and the transverse momentum spectrum. The large transverse momentum spectrum of the Higgs boson produced in gluon fusion can be quite different in the Standard Model and the Minimal Supersymmetric Standard Model. In this paper we present a comparison of the Higgs transverse momentum spectrum obtained using the PYTHIA event generator and the HIGLU program as well as the program HQT, which includes NLO corrections and a soft gluon resummation for the region of small transverse momenta. While the shapes of the spectra are similar for the Standard Model, significant differences are observed in the spectra of Minimal Supersymmetric Standard Model benchmark scenarios with large tan(beta).

hep-ph

Qualification Procedures of the CMS Pixel Barrel Modules

The CMS pixel barrel system will consist of three layers built of about 800 modules. One module contains 66560 readout channels and the full pixel barrel system about 48 million channels. It is mandatory to test each channel for functionality, noise level, trimming mechanism, and bump bonding quality. Different methods to determine the bump bonding yield with electrical measurements have been developed. Measurements of several operational parameters are also included in the qualification procedure. Among them are pixel noise, gains and pedestals. Test and qualification procedures of the pixel barrel modules are described and some results are presented.

physics.ins-det

B physics triggers at CMS

The CMS detector is mainly designed to investigate hard events. Only few Level-1 Trigger conditions are suitable to select soft B-meson decays. The B-physics potential of CMS depends strongly on a selection strategy at High-Level Trigger. The selection algorithms for some benchmark B-decay channels that allow CMS to perform competitive B-physics program are presented.

hep-ph

Bottom Production

We review the prospects for bottom production physics at the LHC.

hep-ph

Observability of B_(d)s-> mu mu decay with the CMS detector

We have updated our previous study on the possibility to observe the rare B0_s -> 2mu decay with detailed simulation of the TDR version of the CMS detector. The full simulation and reconstruction procedure has been done both for the signal and background. We improved our previous results on expected sensitivity using more sophisticated algorithms for the track and vertex reconstruction and tighter selection criteria.

hep-ph