Search for jet extinction in the inclusive jet-pT spectrum from proton-proton collisions at s=8 TeV

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.The first search at the LHC for the extinction of QCD jet production is presented, using data collected with the CMS detector corresponding to an integrated luminosity of 10.7  fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The extinction model studied in this analysis is motivated by the search for signatures of strong gravity at the TeV scale (terascale gravity) and assumes the existence of string couplings in the strong-coupling limit. In this limit, the string model predicts the suppression of all high-transverse-momentum standard model processes, including jet production, beyond a certain energy scale. To test this prediction, the measured transverse-momentum spectrum is compared to the theoretical prediction of the standard model. No significant deficit of events is found at high transverse momentum. A 95% confidence level lower limit of 3.3 TeV is set on the extinction mass scale

Searches for electroweak neutralino and chargino production in channels with Higgs, Z, and W bosons in pp collisions at 8 TeV

Searches for supersymmetry (SUSY) are presented based on the electroweak pair production of neutralinos and charginos, leading to decay channels with Higgs, Z, and W bosons and undetected lightest SUSY particles (LSPs). The data sample corresponds to an integrated luminosity of about 19.5 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV collected in 2012 with the CMS detector at the LHC. The main emphasis is neutralino pair production in which each neutralino decays either to a Higgs boson (h) and an LSP or to a Z boson and an LSP, leading to hh, hZ, and ZZ states with missing transverse energy (E-T(miss)). A second aspect is chargino-neutralino pair production, leading to hW states with E-T(miss). The decays of a Higgs boson to a bottom-quark pair, to a photon pair, and to final states with leptons are considered in conjunction with hadronic and leptonic decay modes of the Z and W bosons. No evidence is found for supersymmetric particles, and 95% confidence level upper limits are evaluated for the respective pair production cross sections and for neutralino and chargino mass values

SiGe bipolar ICs with data rates from 40 to 60 Gb/s for future fiber-optic systems

This paper gives a review on a chip-set of very-high-speed ICs for fiber-optic TDM systems re­alized in a SiGe bipolar laboratory technology. With the uncritical circuits like time-division multiplexer and demultiplexer record data rates of 60 Gb/s were achieved. But even the speed-critical modulator driver and transimpedance amplifier proved to be suited for operation at 40 Gb/s, if an adequate configuration of the TDM system is chosen. It should be noted, that all the experimental results presented, are measured on mounted chips, using conventional wire bonding

Monolithic Low-Noise Amplifiers up to 10 GHz in Silicon and SiGe Bipolar Technologies

The noise properties of silicon and SiGe bipolar technologies at identical de- sign rules are evaluated by theory and by ex- perimental LNAs designed for the frequen- cies of 2 GHz, 6 GHz, and 10 GHz. For a fair comparison the same circuit principle is used for all six LNAs, with gain of about 20 dB or above, suitable for the applications in wireless communications