Luminosity monitors at the LHC

We study the theoretical accuracy of various methods that have been proposed to measure the luminosity of the LHC pp collider, as well as for Run II of the Tevatron p barp collider. In particular we consider methods based on (i) the total and forward elastic data, (ii) lepton-pair production and (iii) W and Z production.Comment: 23 pages, Latex, 9 figure

SiD Letter of Intent

Letter of Intent for SiD detector concept presented to ILC IDAGLetter of intent describing SiD (Silicon Detector) for consideration by the International Linear Collider IDAG panel. This detector concept is founded on the use of silicon detectors for vertexing, tracking, and electromagnetic calorimetry. The detector has been cost-optimized as a general-purpose detector for a 500 GeV electron-positron linear collider

High resolution pixel detectors for e+e- linear colliders

The physics goals at the future e+e- linear collider require high performance vertexing and impact parameter resolution. Two possible technologies for the vertex detector of an experimental apparatus are outlined in the paper: an evolution of the Hybrid Pixel Sensors already used in high energy physics experiments and a new detector concept based on the monolithic CMOS sensors.Comment: 8 pages, to appear on the Proceedings of the International Workshop on Linear Colliders LCWS99, Sitges (Spain), April 28 - May 5, 199

Search for highly-ionizing particles in pp collisions at the LHC's Run-1 using the prototype MoEDAL detector

A search for highly electrically charged objects (HECOs) and magnetic monopoles is presented using 2.2 fb(-1) of p - p collision data taken at a centre of mass energy (E-CM) of 8 TeV by the MoEDAL detector during LHC's Run-1. The data were collected using MoEDAL's prototype Nuclear Track Detectord array and the Trapping Detector array. The results are interpreted in terms of Drell-Yan pair production of stable HECO and monopole pairs with three spin hypotheses (0, 1/2 and 1). The search provides constraints on the direct production of magnetic monopoles carrying one to four Dirac magnetic charges and with mass limits ranging from 590 GeV/c(2) to 1 TeV/c(2). Additionally, mass limits are placed on HECOs with charge in the range 10e to 180e, where e is the charge of an electron, for masses between 30 GeV/c(2) and 1 TeV/c(2).Peer reviewe

Fast-heating-induced formation of metallic-glass/crystal composites with enhanced plasticity

Bulk metallic glasses are known to have poor plasticity which limits their application as structural materials. Due to the lack of atomic periodicity in metallic glasses, their mechanical properties cannot be controlled the same way as in crystalline materials. Fast-heating-induced, a heating rate of 10 K s−1 and higher, crystallization of ductile nanocrystalline phase(s) leads to enhanced plasticity of metallic-glass/crystal composites. Here, an overview of controlling the microstructure on fast heating, the suggested crystallization mechanism of metastable phases and the principle of enhanced plasticity of the composites is presented and discussed, with a special focus on Cu–Zr-based metallic glasses

High Resolution Hybrid Pixel Sensors for the e+e- TESLA Linear Collider Vertex Tracker

In order to fully exploit the physics potential of a future high energy e+e- linear collider, a Vertex Tracker, providing high resolution track reconstruction, is required. Hybrid Silicon pixel sensors are an attractive option, for the sensor technology, due to their read-out speed and radiation hardness, favoured in the high rate environment of the TESLA e+e- linear collider design but have been so far limited by the achievable single point space resolution. In this paper, a conceptual design of the TESLA Vertex Tracker, based on a novel layout of hybrid pixel sensors with interleaved cells to improve their spatial resolution, is presented.Comment: 12 pages, 5 figures, to appear in the Proceedings of the Vertex99 Workshop, Texel (The Netherlands), June 199

Preferred location for conducting filament formation in thin-film nano-ionic electrolyte: study of microstructure by atom-probe tomography

© 2017, The Author(s). Atom-probe tomography of Ag-photodoped amorphous thin-film Ge 40 S 60 , the material of interest in nano-ionic memory and lateral geometry MEMS technologies, reveals regions with two distinct compositions on a nanometer length-scale. One type of region is Ag-rich and of a size typically extending beyond the measured sample volume of ~40 × 40 × 80 nm 3 . These type-I regions contain aligned nanocolumns, ~5 nm wide, that are the likely location for reversible diffusion of Ag + ions and associated growth/dissolution of conducting filaments. The nanocolumns become relatively Ag-rich during the photodoping, and the pattern of Ag enrichment originates from the columnar-porous structure of the as-deposited film that is to some extent preserved in the electrolyte after photodoping. Type-II regions have lower Ag content, are typically 10–20 nm across, and appear to conform to the usual description of the photoreaction products of the optically-induced dissolution and diffusion of silver in a thin-film chalcogenide. The microstructure, with two types of region and aligned nanocolumns, is present in the electrolyte after photodoping without any applied bias, and is important for understanding switching mechanisms, and writing and erasing cycles, in programmable-metallization-cell memory

Measurement of the inclusive-isolated prompt-photon cross section in p(p)over-bar collisions using the full CDF data set

A measurement of the inclusive production cross section of isolated prompt photons in proton-antiproton collisions at center-of-mass energy root s = 1.96 TeV is presented. The results are obtained using the full Run II data sample collected with the Collider Detector at the Fermilab Tevatron, which corresponds to an integrated luminosity of 9.5 fb(-1). The cross section is measured as a function of photon transverse energy, E-T(gamma), in the range 30 <E-T(gamma) <500 GeV and in the pseudorapidity region |eta(gamma)| <1.0. The results are compared with predictions from parton-shower Monte Carlo models at leading order in QCD and from next-to-leading-order perturbative QCD calculations. The latter show good agreement with the measured cross section.Peer reviewe

Central Diffraction at the LHCb

The LHCb experiment is shown to be ideal for studies of exclusive final states from central diffractive reactions. The gluon-rich environment of the central system allows detailed QCD studies and searches for exotic meson states, such as glueballs, molecules, hybrids and new charmonium-like states. It would also provide a good testing ground for detailed studies of heavy quarkonia. Due to its distinct design features, the LHCb can accurately measure the low-mass central systems with good purity. The efficiency of the FSC system for detecting rapidity gaps is shown to be adequate for the proposed studies. With this detector arrangement, valuable new data can be obtained by tagging central diffractive processes