Motion of CMS detector and mechanical structures during Magnet Cycles and Stability Periods from 2008 to 2013 as observed by the Link Alignment System

2016 ◽  
Vol 813 ◽  
pp. 36-55 ◽  
Author(s):  
P. Arce ◽  
J.M. Barcala ◽  
E. Calvo ◽  
A. Ferrando ◽  
M.I. Josa ◽  
...  
Keyword(s):  
Alignment System ◽  
Cms Detector

On-line alignment and astigmatism correction using a TV and personal computer

1993 ◽  
Vol 51 ◽  
pp. 202-203
Author(s):  
F. Hosokawa ◽  
Y. Kondo ◽  
T. Honda ◽  
Y. Ishida ◽  
M. Kersker
Keyword(s):  
High Resolution ◽  
Personal Computer ◽  
Block Diagram ◽  
Incident Beam ◽  
Ccd Camera ◽  
Alignment Procedure ◽  
Astigmatism Correction ◽  
Transmission Electron ◽  
Alignment System ◽  
On Line

High-resolution transmission electron microscopy must attain utmost accuracy in the alignment of incident beam direction and in astigmatism correction, and that, in the shortest possible time. As a method to eliminate this troublesome work, an automatic alignment system using the Slow-Scan CCD camera has been introduced recently. In this method, diffractograms of amorphous images are calculated and analyzed to detect misalignment and astigmatism automatically. In the present study, we also examined diffractogram analysis using a personal computer and digitized TV images, and found that TV images provided enough quality for the on-line alignment procedure of high-resolution work in TEM. Fig. 1 shows a block diagram of our system. The averaged image is digitized by a TV board and is transported to a computer memory, then a diffractogram is calculated using an FFT board, and the feedback parameters which are determined by diffractogram analysis are sent to the microscope(JEM- 2010) through the RS232C interface. The on-line correction system has the following three modes.

scholarly journals A high-resolution solar spectrum 2000 Å–2200 Å

1970 ◽  
Vol 36 ◽  
pp. 271-273
Author(s):  
B. B. Jones ◽  
B. C. Boland ◽  
R. Wilson ◽  
S. T. F. Engstrom
Keyword(s):  
High Resolution ◽  
Solar Spectrum ◽  
Solar Image ◽  
Roll Control ◽  
North East ◽  
The North ◽  
Alignment System ◽  
Optical Alignment ◽  
South Axis ◽  
System Operating

A high-resolution solar spectrum in the range 2000–2200 Å was obtained in a recent flight of a sunpointing Skylark rocket. This was launched at 04.21 hr UT on April 22, 1969 from Woomera and reached an apogee of 178 km. An optical alignment system operating on the main vehicle pointing system gave a net stabilisation of ±3 arc sec in the position of the solar image relative to the spectrograph slit. The slit, of length 1.0 mm, was set in the north-east quadrant parallel to and 5 arc min from the north/south axis, its lower edge being 1 arc min from the equator. The roll control of ±2.5° was provided entirely by the standard Elliott Bros. type of vehicle stabilisation.

scholarly journals Upgrade of CMS Full Simulation for Run 2

2019 ◽  
Vol 214 ◽  
pp. 02012
Author(s):  
Vladimir Ivanchenko ◽  
Sunanda Banerjee
Keyword(s):  
Monte Carlo ◽  
Simulation Software ◽  
Pixel Detector ◽  
Test Beam ◽  
Hadronic Calorimeter ◽  
Cms Detector ◽  
The Status ◽  
Full Simulation

We report on the status of the CMS full simulation software for Run 2 operations of the LHC. Initially, Geant4 10.0p02 was used and about 16 billion events were produced for analysis of 2015-2016 data. In 2017, the CMS detector was updated with a new tracking pixel detector, a modified hadronic calorimeter electronics, and extra muon detectors added. Corresponding modifications were introduced in the full simulation and Geant4 10.2p02 was adopted for 2017 simulation productions; that includes an improved Geant4 for multi-threaded mode, which became the default for 2017. For the 2018 Monte Carlo productions, the full simulation has been updated further. The new Geant4 version 10.4 is used, adopted for the production after detailed validations using test-beam and collision data. The results of validations will be described in details. Several aspects of the migration to Geant4 10.4 and modifications in CMSSW simulation software will be also discussed.

Progress on the active alignment system for the IXO mirrors

2009 ◽  
Author(s):  
Mark D. Freeman ◽  
Paul B. Reid ◽  
William Podgorski ◽  
David Caldwell
Keyword(s):  
Alignment System

scholarly journals Alignment Layer of Liquid Crystal Using Plant-Based Isoeugenol-Substituted Polystyrene

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 547
Author(s):  
DaEun Yang ◽  
Kyutae Seo ◽  
Hyo Kang
Keyword(s):  
Liquid Crystal ◽  
Surface Energy ◽  
Polymer Film ◽  
Uv Irradiation ◽  
Molar Content ◽  
Polymer Modification ◽  
Alignment Layer ◽  
Energy Value ◽  
Alignment System ◽  
Molar Percent

We synthesized a series of renewable and plant-based isoeugenol-substituted polystyrenes (PIEU#, # = 100, 80, 60, 40, and 20, where # is the molar percent content of isoeugenol moiety), using polymer modification reactions to study their liquid crystal (LC) alignment behavior. In general, the LC cells fabricated using polymer film with a higher molar content of isoeugenol side groups showed vertical LC alignment behavior. This alignment behavior was well related to the surface energy value of the polymer layer. For example, vertical alignments were observed when the polar surface energy value of the polymer was smaller than approximately 3.59 mJ/m2, generated by the nonpolar isoeugenol moiety with long and bulky carbon groups. Good alignment stability at 100 °C and under ultraviolet (UV) irradiation of 15 J/cm2 was observed for the LC cells fabricated using PIEU100 as a LC alignment layer. Therefore, renewable isoeugenol-based materials can be used to produce an eco-friendly vertical LC alignment system.

scholarly journals Misalignment in Gas Foil Journal Bearings: An Experimental Study

2008 ◽  
Author(s):  
Samuel A. Howard
Keyword(s):  
Journal Bearings ◽  
System Level ◽  
Design Parameters ◽  
Foil Bearing ◽  
Alignment System ◽  
Successful Design ◽  
Shaft Alignment ◽  
Bearing Force ◽  
Management Schemes ◽  
Level Performance

As gas foil journal bearings become more prevalent in production machines, such as small gas turbine propulsion systems and microturbines, system level performance issues must be identified and quantified in order to provide for successful design practices. Several examples of system level design parameters that are not fully understood in foil bearing systems are thermal management schemes, alignment requirements, balance requirements, thrust load balancing, and others. In order to address some of these deficiencies and begin to develop guidelines, this paper presents a preliminary experimental investigation of the misalignment tolerance of gas foil journal bearing systems. Using a notional gas foil bearing supported rotor and a laser-based shaft alignment system, increasing levels of misalignment are imparted to the bearing supports while monitoring temperature at the bearing edges. The amount of misalignment that induces bearing failure is identified and compared to other conventional bearing types such as cylindrical roller bearings and angular contact ball bearings. Additionally, the dynamic response of the rotor indicates that the gas foil bearing force coefficients may be affected by misalignment.

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