1,129 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Alignment"  
prev Results: 937 - 960 next
open access

IR Spectrometer Using 90-Degree Off-Axis Parabolic Mirrors

Description: A gated spectrometer has been designed for real-time, pulsed infrared (IR) studies at the National Synchrotron Light Source at the Brookhaven National Laboratory. A pair of 90-degree, off-axis parabolic mirrors are used to relay the light from an entrance slit to an output recording camera. With an initial wavelength range of 1500–4500 nm required, gratings could not be used in the spectrometer because grating orders would overlap. A magnesium oxide prism, placed between these parabolic mirrors… more
Date: March 1, 2008
Creator: Malone, Robert M. & McKenna, Ian J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

EE&RE, Session: CdTe - Progress and Roadmap Alignment

Description: This project supports the Solar America Initiative by: (1) assistance to SAI Incubators (Primestar Solar, AvA Solar); (2) providing industry with baseline understanding of CdS/CdTe device formation and reliability--incorporation of low-cost, high quality TCOs, functionality and options for buffer layers, effect of various CdS options, effect of and importance CdSTe alloy formation, effect and options for CdCl{sub 2} treatment, effect and options for back contact, and effect of residual impuriti… more
Date: April 1, 2008
Creator: Gessert, T.
Item Type: Refine your search to only Presentation
Partner: UNT Libraries Government Documents Department
open access

Fast Implementation of Matched Filter Based Automatic Alignment Image Processing

Description: Video images of laser beams imprinted with distinguishable features are used for alignment of 192 laser beams at the National Ignition Facility (NIF). Algorithms designed to determine the position of these beams enable the control system to perform the task of alignment. Centroiding is a common approach used for determining the position of beams. However, real world beam images suffer from intensity fluctuation or other distortions which make such an approach susceptible to higher position meas… more
Date: April 2, 2008
Creator: Awwal, A. S.; Rice, K. & Taha, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Alignment of the Near Detector scintillator modules using cosmic ray muons

Description: The authors describe the procedures and the results of the first alignment of the Near Detector. Using 15.5 million cosmic ray muon tracks, collected from October, 2004 through early january, 2005, they derive the effective transverse positions of the calorimeter scintillator modules. The residuals from straight line fits indicate that the current alignment has achieved better than 1 mm precision. They estimate the size of the remaining misalignment and using tracks recorded with a magnetic fie… more
Date: May 1, 2008
Creator: Ospanov, Rustem; Lang, Karol & U., /Texas
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nb3Sn Quadrupoles Designs For The LHC Upgrades

Description: In preparation for the LHC luminosity upgrades, high field and large aperture Nb{sub 3}Sn quadrupoles are being studied. This development has to incorporate all the relevant features for an accelerator magnet like alignment and cooling channels. The LARP HQ model is a high field and large bore quadrupole that will meet these requirements. The 2-layer coils are surrounded by a structure based on key and bladder technology with supporting iron yoke and aluminum shell. This structure is aimed at p… more
Date: May 19, 2008
Creator: Felice, Helene
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Challenges and concepts for design of an interaction region with push-pull arrangement of detectors - an interface document

Description: Two experimental detectors working in a push-pull mode has been considered for the Interaction Region of the International Linear Collider [1]. The push-pull mode of operation sets specific requirements and challenges for many systems of detector and machine, in particular for the IR magnets, for the cryogenics and alignment system, for beamline shielding, for detector design and overall integration, and so on. These challenges and the identified conceptual solutions discussed in the paper inte… more
Date: June 1, 2008
Creator: Parker, B.; /Brookhaven; Herve, A.; Osborne, J.; /CERN; Mikhailichenko, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transatlantic transport of Fermilab 3.9 GHz cryomodule for TTF/FLASH to DESY

Description: In an exchange of technology agreement, Fermilab built and will deliver a 3.9 GHz (3rd harmonic) cryomodule to DESY to be installed in the TTF/FLASH beamline. This cryomodule delivery will involve a combination of flatbed air ride truck and commercial aircraft transport to Hamburg Germany. A description of the isolation and damping systems that maintain alignment during transport and protect fragile components is provided. Initially, transport and corresponding alignment stability studies were … more
Date: June 1, 2008
Creator: McGee, M. W.; Vocean, V.; Grimm, C. & Schappert, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam

Description: A small set of final prototypes of the ATLAS Inner Detector silicon tracking system(Pixel Detector and SemiConductor Tracker), were used to take data during the 2004 Combined Test Beam. Data were collected from runs with beams of different flavour (electrons, pions, muons and photons) with a momentum range of 2 to 180 GeV/c. Four independent methods were used to align the silicon modules. The corrections obtained were validated using the known momenta of the beam particles and were shown to yie… more
Date: June 2, 2008
Creator: Ahmad, A.; Andreazza, A.; Atkinson, T.; Baines, J.; Barr, A. J.; Beccherle, R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Machine-Detector Interface Issues for the ILCPolarimeters

Description: This note examines several Machine-Detector Interface (MDI) issues for the Compton polarimeters in the Beam Delivery System of the International Linear Collider (ILC), including (1) alignment tolerances, (2) impact of crossing angle and IR magnets on spin alignment, (3) Z-pole operation, and (4) costs and conventional facilities.
Date: June 13, 2008
Creator: Woods, Mike
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Performance of a Fast Closed Orbit Feedback System with Combined Fast and Slow Correctors

Description: For NSLSII closed orbit feedback system, in order to limit the noise caused by digital step changes of the power supplies in the feedback system, the angular kick corresponding to the last bit of the power supplies for the fast correctors must be smaller than 3 nrad [1]. On the other hand, to carry out closed orbit alignment or orbit correction after a long term drift, they need strong correctors with 0.8 mrad kick strength. In order to avoid the requirement of correctors with both large streng… more
Date: June 23, 2008
Creator: Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beam-Based Alignment, Tuning and Beam Dynamics Studies for the ATF2 Extraction Line and Final Focus System

Description: Using a new extraction line currently under construction, the ATF2 experiment plans to test the novel compact final focus optics design with local chromaticity correction intended for use in future linear colliders. With a 1.3 GeV design beam of 30nm normalized vertical emittance extracted from the ATF damping ring, the primary goal is to achieve a vertical spot-size at the IP waist of 37nm. We discuss our planned strategy for tuning the ATF2 beam to meet the primary goal. Simulation studies ha… more
Date: July 25, 2008
Creator: White, Glen R.; /LAL, Orsay /SLAC; Molloy, S.; Woodley, M. & /SLAC
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transverse centroid oscillations in solenoidially focused beam transport lattices

Description: Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable"alignment functions" and"bending functions" that efficiently describe the characteristics of the centroid oscillations induced by me… more
Date: August 1, 2008
Creator: Lund, Steven M.; Wootton, Christopher J. & Lee, Edward P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photodeposition of Pt on Colloidal CdS and CdSe/CdS Semiconductor Nanostructures

Description: Semiconductor photocatalysis has been identified as a promising avenue for the conversion of solar energy into environmentally friendly fuels, most notably by the production of hydrogen from water.[1-5] Nanometer-scale materials in particular have attracted considerable scientific attention as the building blocks for light-harvesting applications.[6,7] Their desirable attributes include tunability of the optical properties with size, amenability to relatively inexpensive low-temperature process… more
Date: August 6, 2008
Creator: Dukovic, Gordana; Merkle, Maxwell G.; Nelson, James H.; Hughes, Steven M. & Alivisatos, A. Paul
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A Theoretical Study of the Two-Dimensional Point Focusing by Two Multilayer Laue Lenses.

Description: Hard x-ray point focusing by two crossed multilayer Laue lenses is studied using a full-wave modeling approach. This study shows that for a small numerical aperture, the two consecutive diffraction processes can be decoupled into two independent ones in respective directions. Using this theoretical tool, we investigated adverse effects of various misalignments on the 2D focus profile and discussed the tolerance to them. We also derived simple expressions that described the required alignment ac… more
Date: August 10, 2008
Creator: Yan,H.; Maser, J.; Kang, H.C.; Macrader, A. & Stephenson, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Magneto-optical study of the intermediate state in type-I superconductors: Effects of sample shape and applied current

Description: The magnetic flux structures in the intermediate state of bulk, pinning-free Type-I superconductors are studied using a high resolution magneto-optical imaging technique. Unlike most previous studies, this work focuses on the pattern formation of the coexisting normal and superconducting phases in the intermediate state. The influence of various parameters such as sample shape, structure defects (pinning) and applied current are discussed in relation to two distinct topologies: flux tubes (clos… more
Date: August 15, 2008
Creator: Hoberg, Jacob
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Design of HQ -- a High Field Large Bore Nb3Sn Quadrupole Magnet for LARP

Description: In support of the Large Hadron Collider luminosity upgrade, a large bore (120 mm) Nb{sub 3}Sn quadrupole with 15 T peak coil field is being developed within the framework of the US LHC Accelerator Research Program (LARP). The 2-layer design with a 15 mm wide cable is aimed at pre-stress control, alignment and field quality while exploring the magnet performance limits in terms of gradient, forces and stresses. In addition, HQ will determine the magnetic, mechanical, and thermal margins of Nb{su… more
Date: August 17, 2008
Creator: Felice, H.; Ambrosio, G.; Anerella, M.; Bossert, R.; Caspi, S.; Cheng, D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Alignment validation

Description: The four experiments, ALICE, ATLAS, CMS and LHCb are currently under constructionat CERN. They will study the products of proton-proton collisions at the Large Hadron Collider. All experiments are equipped with sophisticated tracking systems, unprecedented in size and complexity. Full exploitation of both the inner detector andthe muon system requires an accurate alignment of all detector elements. Alignmentinformation is deduced from dedicated hardware alignment systems and the reconstruction … more
Date: September 6, 2008
Creator: ALICE; ATLAS; CMS; LHCb & Golling, Tobias
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design and Fabrication of a Radiation-Hard 500-MHz Digitizer Using Deep Submicron Technology

Description: The proposed International Linear Collider (ILC) will use tens of thousands of beam position monitors (BPMs) for precise beam alignment. The signal from each BPM is digitized and processed for feedback control. We proposed the development of an 11-bit (effective) digitizer with 500 MHz bandwidth and 2 G samples/s. The digitizer was somewhat beyond the state-of-the-art. Moreover we planned to design the digitizer chip using the deep-submicron technology with custom transistors that had proven to… more
Date: September 12, 2008
Creator: Gan, K.K.; Johnson, M.O.; Kass, R.D. & Moore, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

805 MHz Beta = 0.47 Elliptical Accelerating Structure R & D

Description: A 6-cell 805 MHz superconducting cavity for acceleration in the velocity range of about 0.4 to 0.53 times the speed of light was designed. After single-cell prototyping, three 6-cell niobium cavities were fabricated. In vertical RF tests of the 6-cell cavities, the measured quality factors (Q{sub 0}) were between 7 {center_dot} 10{sup 9} and 1.4 {center_dot} 10{sup 10} at the design field (accelerating gradient of 8 to 10 MV/m). A rectangular cryomodule was designed to house 4 cavities per cryo… more
Date: September 22, 2008
Creator: Bricker, S.; Compton, C.; Hartung, W.; Johnson, M.; Marti, F.; Popierlarski, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mapping of ion beam induced current changes in FinFETs

Description: We report on progress in ion placement into silicon devices with scanning probealignment. The device is imaged with a scanning force microscope (SFM) and an aligned argon beam (20 keV, 36 keV) is scanned over the transistor surface. Holes in the lever of the SFM tip collimate the argon beam to sizes of 1.6 mu m and 100 nm in diameter. Ion impacts upset the channel current due to formation of positive charges in the oxide areas. The induced changes in the source-drain current are recorded in dep… more
Date: September 30, 2008
Creator: Weis, C. D.; Schuh, A.; Batra, A.; Persaud, A.; Rangelow, I. W.; Bokor, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Acclerator R&D for a Linear Collider

Description: The goal of this project was to perform simulations of beam transport in linear colliders, with an emphasis on emittance dilution, spin polarization transport, and development and testing of beam based tuning algorithms. Our simulations are based on an existing object-oriented particle-tracking library, Bmad. To facilitate the efficient development of simulations, an accelerator design and analysis program based on Bmad has been developed called Tao (Tool for Accelerator Optics). The three beam… more
Date: November 26, 2008
Creator: Rubin, D.L.; Dugan, G.; Gibbons, L.; Palmer, M.; Patterson, R.; Sagan, D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Control System Applicable Use Assessment of the Secure Computing Corporation - Secure Firewall (Sidewinder)

Description: Battelle’s National Security & Defense objective is, “applying unmatched expertise and unique facilities to deliver homeland security solutions. From detection and protection against weapons of mass destruction to emergency preparedness/response and protection of critical infrastructure, we are working with industry and government to integrate policy, operational, technological, and logistical parameters that will secure a safe future”. In an ongoing effort to meet this mission, engagements wit… more
Date: January 1, 2009
Creator: Hadley, Mark D. & Clements, Samuel L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen