Functional Wigner representation of BEC quantum dynamics

We develop a method of simulating the full quantum field dynamics of multi-mode multi-component Bose-Einstein condensates in a trap. We use the truncated Wigner representation to obtain a probabilistic theory that can be sampled. This method produces c-number stochastic equations which may be solved using conventional stochastic methods. The technique is valid for large mode occupation numbers. We give a detailed derivation of methods of functional Wigner representation appropriate for quantum fields. Our approach describes spatial evolution of spinor components and properly accounts for nonlinear losses. Such techniques are applicable to calculating the leading quantum corrections, including effects like quantum squeezing, entanglement, EPR correlations and interactions with engineered nonlinear reservoirs. By using a consistent expansion in the inverse density, we are able to explain an inconsistency in the nonlinear loss equations found by earlier authors

Peptide mass fingerprinting using field-programmable gate arrays

The reconfigurable computing paradigm, which exploits the flexibility and versatility of field-programmable gate arrays (FPGAs), has emerged as a powerful solution for speeding up time-critical algorithms. This paper describes a reconfigurable computing solution for processing raw mass spectrometric data generated by MALDI-TOF instruments. The hardware-implemented algorithms for denoising, baseline correction, peak identification, and deisotoping, running on a Xilinx Virtex-2 FPGA at 180 MHz, generate a mass fingerprint that is over 100 times faster than an equivalent algorithm written in C, running on a Dual 3-GHz Xeon server. The results obtained using the FPGA implementation are virtually identical to those generated by a commercial software package MassLynx

W' signatures with odd Higgs particles

We point out that W' bosons may decay predominantly into Higgs particles associated with their broken gauge symmetry. We demonstrate this in a renormalizable model where the W' and W couplings to fermions differ only by an overall normalization. This "meta-sequential" W' boson decays into a scalar pair, with the charged one subsequently decaying into a W boson and a neutral scalar. These scalars are odd under a parity of the Higgs sector, which consists of a complex bidoublet and a doublet. The W' and Z' bosons have the same mass and branching fractions into scalars, and may show up at the LHC in final states involving one or two electroweak bosons and missing transverse energy.Comment: 24 page

Coupling spans of the Higgs-like boson

Using the LHC and Tevatron data, we set upper and lower limits on the total width of the Higgs-like boson. The upper limit is based on the well-motivated assumption that the Higgs coupling to a W or Z pair is not much larger than in the Standard Model. These width limits allow us to convert the rate measurements into ranges for the Higgs couplings to various particles. A corollary of the upper limit on the total width is an upper limit on the branching fraction of exotic Higgs decays. Currently, this limit is 47% at the 95% CL if the electroweak symmetry is broken only by doublets.Comment: 18 pages, 2 figures; v2: Minor clarifications, references adde