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A novel method for sub-micrometer transverse electron beam size measurements using optical transition radiation

A Aryshev, S T Boogert, D Howell, P Karataev, N Terunuma, J Urakawa
2010 Journal of Physics, Conference Series  
In our experiment we managed to create a system which can practically measure the PSF distribution and using a new self-calibration method we are able to calculate transverse electron beam size.  ...  Here we represent the development, data analysis and novel calibration technique of a sub-micrometer electron beam profile monitor based on the measurements of the PSF shape, which visibility is sensitive  ...  , European Commission under the FP7 Research Infrastructures project EuCARD, grant agreement no.227579, and Quantum Beam Technology Program of the Ministry of Education, Science, Sports, Culture and Technology  ... 
doi:10.1088/1742-6596/236/1/012008 fatcat:ng3upmjt4fdobkh5m6nf3wia5q

CALIBRATION AND UPGRADE OF THE ECE IMAGING DIAGNOSTIC FOR TEXTOR

M.J. van de Pol, A.J.H. Donné, B.H. Deng, C.W. Domier, N.C. Luhmann, E. Mazzucato, T. Munsat, H. Park
2003 Electron Cyclotron Emission and Electron Cyclotron Heating  
Electron Cyclotron Emission Imaging (ECEI) in TEXTOR measures the electron cyclotron emission (ECE) of a tokamak plasma along the same vertical observation chord as Thomson scattering.  ...  The upgrade of the present TEXTOR system to a broadband receiver, to obtain a 2-dimensional measurement capability, and the integration with a Microwave Imaging Reflectometer (MIR) is presented.  ...  Electron Cyclotron Emission Imaging (ECEI) is a diagnostic technique that has been applied successfully to the TEXT-U, RTP and TEXTOR tokamaks [1] [2] [3] [4] and the LHD and W7-AS stellarators [5,  ... 
doi:10.1142/9789812705082_0031 fatcat:hguwqaclr5esdbbkfwqixyuz5e

Calibrating the TEM

John P. McCaffrey
1997 Microscopy Today  
to 10%, These errors can occur due to variations in lenses in individual microscopes as well as through power supply variations and aging electronic components.  ...  An accurate calibration of magnification, diffraction patterns and the relative rotation between the two is critical in quantitative transmission electron microscopy (TEM).  ...  in lenses in individual microscopes as well as through power supply variations and aging electronic components.  ... 
doi:10.1017/s1551929500060569 fatcat:rsvlfmnamzhdth7rtwjgjz3tta

Picometer-scale accuracy in pitch metrology by optical diffraction and atomic force microscopy

Donald A. Chernoff, Egbert Buhr, David L. Burkhead, Alexander Diener, John A. Allgair, Christopher J. Raymond
2008 Metrology, Inspection, and Process Control for Microlithography XXII  
Magnification error and image nonlinearity are by far the largest errors present in the original data.  ...  The graph shows that there was no significant variation in mean pitch from image to image. Data Measurement uncertainty Measured errors (type A).  ... 
doi:10.1117/12.768429 fatcat:c4ezc5osb5bxzchxaosddod4ja

Limits on the validity of the thin-layer model of the ionosphere for radio interferometric calibration

Poppy L. Martin, Justin D. Bray, Anna M. M. Scaife
2016 Monthly notices of the Royal Astronomical Society  
For a ground-based radio interferometer observing at low frequencies, the ionosphere causes propagation delays and refraction of cosmic radio waves which result in phase errors in the received signal.  ...  angle, interferometer latitude, baseline length, ionospheric electron content and observing frequency.  ...  , and the consequent error in the ionospheric phase calibration of a radio synthesis telescope.  ... 
doi:10.1093/mnras/stw853 fatcat:muz3sjkn4fepjf5umfvkvsvvsq

Modeling, calibration, and correction of nonlinear illumination-dependent fixed pattern noise in logarithmic CMOS image sensors

D. Joseph, S. Collins
2002 IEEE Transactions on Instrumentation and Measurement  
Experiments with a Fuga 15d image sensor, demonstrating parameter calibration and FPN correction, show that the nonlinear model outperforms previous models that assume either only offset or offset and  ...  gain variation.  ...  Modeling, Calibration, and Correction of Nonlinear Illumination-Dependent Fixed Pattern Noise in Logarithmic CMOS Image Sensors Dileepan Joseph and Steve Collins Abstract-At present, most CMOS image sensors  ... 
doi:10.1109/tim.2002.807803 fatcat:uyswpworbjhnveuoq3o52b6zne

Investigation of pixel scale calibration on the Elekta iView electronic portal imager

Craig Norvill, Simon Goodall
2021 Journal of Applied Clinical Medical Physics  
Other factors such as focal spot size and shape, electronic portal imager manufacturing consistency, panel sag, and setup errors may account for the residual variation.  ...  This study investigated the variation in electronic portal imager pixel scale at the isocenter plane for Elekta Agility linear accelerators.  ...  | Pixel scale factor variation with calibration plate Portal images of each of the eight calibration plates were acquired on machine "A" in a single session. (1) Gantry and collimator were set to 0º  ... 
doi:10.1002/acm2.13339 pmid:34250752 fatcat:hnnmvfcffjavbda2uiaqaljvwq

Assessment of the dosimetric accuracies of CATPhan 504 and CIRS 062 using kV-CBCT for performing direct calculations

JamesKwame Annkah, Naina Hindocha, SyedAli Moinuddin, Kate Ricketts, Ivan Rosenberg, Gary Royle, Abiodun Adeyemi
2014 Journal of Medical Physics  
All computations were done using the images and dataset from kV-CBCT while maintaining the HU-ED calibration curve of the planning CT (pCT), assuming pCT was used for the initial treatment plan.  ...  The dosimetric accuracies of CATPhan 504 and CIRS 062 have been evaluated using the kV-CBCT of Varian TrueBeam linac and Eclipse TPS.  ...  Derek D'Souza of UCLH Radiotherapy Physics, staff of Harley Street Clinic (HCA at ULCH), the Staff of UCLH Radiotherapy Physics Department, all CT and Linac radiographers at UCLH, and the Head of Radiotherapy  ... 
doi:10.4103/0971-6203.139001 pmid:25190991 pmcid:PMC4154180 fatcat:cvf2nu7bqjgmhjo4c3snpdy4zu

A Reverse Engineering Approach for Imaging Neuronal Architecture – Large-Area, High-Resolution SEM Imaging

Christine A. Brantner, Martin Rasche, Kevin E. Burcham, Joseph Klingfus, Joel Fridmann, Jason E. Sanabia, Can E. Korman, Anastas Popratiloff
2016 Microscopy Today  
A reverse engineering approach to scanning electron microscope (SEM) imaging of neuronal architecture provides largearea maps of a sample, which links the function of a cell with its location in a tissue  ...  The Chipscanner's laser interferometer stage and field-of-view mapping allow high-resolution SEM images to be stitched together.  ...  This work was funded in part by NIH grants P30HD040677 (IDDRC at CNMC) and P01HD083157 (Pathology, Developmental Origins, and Prevention of Pediatric Dysphagia).  ... 
doi:10.1017/s1551929516000730 fatcat:2imajajylrdajii5hmymugffhy

An investigation into factors affecting electron density calibration for a megavoltage cone-beam CT system

Jessica Hughes, Lois C. Holloway, Alexandra Quinn, Andrew Fielding
2012 Journal of Applied Clinical Medical Physics  
Dose distributions from treatment plans calculated with simulated image data from a 15 MU head and neck reconstruction filter MV CBCT image and a MV CBCT ED calibration curve from the image data parameters  ...  A Gammex electron density CT phantom containing EDs from 0.292 to 1.707 was imaged under each of these conditions.  ...  Similar small differences were seen for the head and neck treatment plan with changes in the MV CBCTsimulated image and the MV CBCT electron density calibration curve.  ... 
doi:10.1120/jacmp.v13i5.3271 pmid:22955638 pmcid:PMC5718240 fatcat:bu3d7ollozdmfn77isyrms5q3a

Absolutely Calibrated Soft X-Ray Streak Camera For Laser Fusion Applications

Robert L. Kauffman, Gary Stradling, Hector Medecki, Lincoln L. Endelman
1983 15th Intl Congress on High Speed Photography and Photonics  
The image converter tube dependent quantities are the electron transmission efficiency, e, image magnification along the slitII-5- and in the time direction, m and m , respectively, and the electron  ...  By including it on each piece of data errors due to variations in film processing are reduced. With film, dynamic ranges of over 1000 are obtainable.  ... 
doi:10.1117/12.967830 fatcat:ehl6kvhirraoxksemhuggkcfg4

The impact of mass density variations on an electron Monte Carlo algorithm for radiotherapy dose calculations

Raymond Fang, Thomas Mazur, Sasa Mutic, Rao Khan
2018 Physics and Imaging in Radiation Oncology  
Upper and lower variations in CT number to mass density calibration yielded mean values of V50% that were 4.4% larger and 2.1% smaller than reference values respectively.  ...  Electron beam dose was calculated for ten patients using these variations and the results were compared to clinical plans originally derived with a reference calibration table.  ...  Physics and Imaging in Radiation Oncology 8 (2018) 1-7  ... 
doi:10.1016/j.phro.2018.10.002 pmid:33458409 pmcid:PMC7807677 fatcat:ltyah2ofkfgwrnm6f2scphzcdm

Influence of electron density spatial distribution and X-ray beam quality during CT simulation on dose calculation accuracy

Ahmad Nobah, Belal Moftah, Nada Tomic, Slobodan Devic
2011 Journal of Applied Clinical Medical Physics  
The impact of various kVp settings and electron density (ED) distribution on the accuracy of dose calculation in high-energy photon beams was found to be well within 2%.  ...  setups and kVp settings.  ...  While the observed dose errors increase with depth in low electron beams, it appears that in the highest (18 MeV) energy electron beam, dose errors actually decrease with depth.  ... 
doi:10.1120/jacmp.v12i3.3432 fatcat:emqninmulvgx5cnsyp54fzoplu

Influence of electron density spatial distribution and X-ray beam quality during CT simulation on dose calculation accuracy

Ahmad Nobah, Belal Moftah, Nada Tomic, Slobodan Devic
2011 Journal of Applied Clinical Medical Physics  
The impact of various kVp settings and electron density (ED) distribution on the accuracy of dose calculation in high-energy photon beams was found to be well within 2%.  ...  setups and kVp settings.  ...  While the observed dose errors increase with depth in low electron beams, it appears that in the highest (18 MeV) energy electron beam, dose errors actually decrease with depth.  ... 
pmid:21844854 pmcid:PMC5718643 fatcat:a3odvncfj5eg7ly4uocfuxwmme

Dosimetric impact of computed tomography calibration on a commercial treatment planning system for external radiation therapy

Luca Cozzi, Antonella Fogliata, Francesca Buffa, Sabine Bieri
1998 Radiotherapy and Oncology  
The impact of an average calibration table provided by the manufacturer on computed doses was investigated when a customer calibration could not be included in the TPS.  ...  The applied voltage was the most relevant parameter leading to errors in the reconstructed Hounsfield numbers of about 300 units for high densities.  ...  a possible correlation between Hounsfield units and electron (and/or mass) densities).  ... 
doi:10.1016/s0167-8140(98)00072-3 pmid:9925254 fatcat:ok7i3hyqmjbyzkxpfncrtdj4ce
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