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1994 SSRL Activity Report

Description: SSRL, a division of the Stanford Linear Accelerator Center, is a national user facility which provides synchrotron radiation, a name given to x-rays or light produced by electrons circulating in a storage ring at nearly the speed of light. The synchrotron radiation is produced by the 3.3 GeV storage ring, SPEAR. SPEAR is a fully dedicated synchrotron radiation facility which has been operating for user experiments 6 to 7 months per year. 1994, the third year of operation of SSRL as a fully dedi… more
Date: November 18, 2011
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Matlab Based LOCO

Description: The LOCO algorithm has been used by many accelerators around the world. Although the uses for LOCO vary, the most common use has been to find calibration errors and correct the optics functions. The light source community in particular has made extensive use of the LOCO algorithms to tightly control the beta function and coupling. Maintaining high quality beam parameters requires constant attention so a relatively large effort was put into software development for the LOCO application. The LOCO… more
Date: October 18, 2011
Creator: Portmann, Greg; Safranek, James & Huang, Xiaobiao
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On the Kinematics of Undulator Girder Motion

Description: The theory of rigid body kinematics is used to derive equations that govern the control and measurement of the position and orientation of undulator girders. The equations form the basis of the girder matlab software on the LCLS control system. The equations are linear for small motion and easily inverted as desired. For reference, some relevant girder geometrical data is also given. Equations 6-8 relate the linear potentiometer readings to the motion of the girder. Equations 9-11 relate the ca… more
Date: August 18, 2011
Creator: Welch, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha Heating in ITER L-mode and H-mode Plasma

Description: There are many uses of predictions of ITER plasma performance. One is assessing requirements of different plasma regimes. For instance, what current drive and control are needed for steady state. The heating, current drive, and torque systems planned for initial DT operation are negative ion neutral beam injection (NB), ion cyclotron resonance (IC), and electron cyclotron resonance (EC). Which combinations of heating are optimal. What are benefits of the torques, current drive, and fueling usin… more
Date: July 18, 2011
Creator: Budny, R.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of Ds Decays at BaBar

Description: We present a measurement of the absolute branching fractions {Beta}(D{sub s}{sup -} {yields} {mu}{sup -}{bar {nu}}{sub {mu}}) and {Beta}(D{sub s}{sup -} {yields} {tau}{sup -}{bar {nu}}{sub {tau}}) and of the D{sub s} decay constant, f{sub D{sub s}}. They also obtain an upper limit on {Beta}(D{sub s}{sup -} {yields} e{bar {nu}}{sub e}). Then they present results on Dalitz plot analysis of D{sub s}{sup +} decays to K{sup +}K{sup -}{pi}{sup +} and {pi}{sup +}{pi}{sup -}{pi}{sup +}. The {pi}{sup +}… more
Date: August 18, 2011
Creator: Pappagallo, Marco
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CRADA 2009S001: Investigation of the Supercondcuting RF Properties of Large Grain Ingot Niobium

Description: This CRADA intended to explore the properties of large grain ingot niobium by fabricating four single cell TESLA shaped accelerating cavities. Once the cavities were fabricated, SRF performance would be measured. Niowave received four discs of large grain ingot niobium from JLAB in February 2009. Niowave cut samples from each disc and tested the RRR. After the RRR was measured with disappointing results, the project lost interest. A no cost extension was signed in July 2009 to allow progress un… more
Date: December 18, 2012
Creator: Terry Grimm, Jerry L. Hollister, Ahren Kolka, Ganapati Rao Myneni
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status of the Super-B factory Design

Description: The SuperB international team continues to optimize the design of an electron-positron collider, which will allow the enhanced study of the origins of flavor physics. The project combines the best features of a linear collider (high single-collision luminosity) and a storage-ring collider (high repetition rate), bringing together all accelerator physics aspects to make a very high luminosity of 10{sup 36} cm{sup -2} sec{sup -1}. This asymmetric-energy collider with a polarized electron beam wil… more
Date: May 18, 2012
Creator: Wittmer, W.; U., /Michigan State; Bertsche, K.; Chao, A.; Novokhatski, A.; Nosochkov, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic Measurement of the Background Field in the Undulator Hall

Description: The steel present in the construction of the undulator hall facility has the potential for changing the ambient fields present in the undulator hall. This note describes a measurement done to make a comparison between the fields in the hall and in the Magnetic Measurement Facility. In order for the undulators to have the proper tuning, the background magnetic field in the Undulator Hall should agree with the background field in the Magnetic Measurements Facility within .5 gauss. In order to ver… more
Date: November 18, 2010
Creator: Fisher, Andrew; Nuhn, Heinz-Dieter & Welch, James
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal Tests of Undulator Quad

Description: Running at the nominal temperature, the undulator quadrupole has a several degree temperature increase. This note describes the test used to determine the effect on the undulator integrals from the temperature gradient caused by the heat from the quadrupole conducting down the beam pipe. The undulator quadrupoles running at their nominal current of 4 amps heat up approximately 4 degrees Celsius; this magnet in turn heats up the beampipe which goes into the undulator. The heating ends up introdu… more
Date: November 18, 2010
Creator: Fisher, Andrew
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Magnetic Measurements of the Background Field in the Undulator Hall with Ductwork and Cable Trays

Description: The duct work and cable trays present in the undulator hall facility are made out of potentially magnetically active materials. This note describes a measurement done to make a comparison between the fields in the undulator hall with the duct work and cable trays present and in the Magnetic Measurement Facility. In order for the undulators to have the proper tuning, the background magnetic field in the Undulator Hall must agree with the background field in the Magnetic Measurements Facility wit… more
Date: November 18, 2010
Creator: Fisher, Andrew; Nuhn, Heinz-Dieter & Welch, James
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Girder Alignment Plan

Description: The girders for the LCLS undulator system contain components which must be aligned with high accuracy relative to each other. The alignment is one of the last steps before the girders go into the tunnel, so the alignment must be done efficiently, on a tight schedule. This note documents the alignment plan which includes efficiency and high accuracy. The motivation for girder alignment involves the following considerations. Using beam based alignment, the girder position will be adjusted until t… more
Date: November 18, 2010
Creator: Wolf, Zachary; Ruland, Robert; LeCocq, Catherine; Lundahl, Eric; Levashov, Yurii; Reese, Ed et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trapping of Electron Cloud LLC/Cesrta Quadrupole and Sextupole Magnets

Description: The Cornell Electron Storage Ring (CESR) has been reconfigured as an ultra low emittance damping ring for use as a test accelerator (CesrTA) for International Linear Collider (ILC) damping ring R&D [1]. One of the primary goals of the CesrTA program is to investigate the interaction of the electron cloud with low emittance positron beam to explore methods to suppress the electron cloud, develop suitable advanced instrumentation required for these experimental studies and benchmark predictio… more
Date: August 18, 2011
Creator: Wang, L. & Pivi, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Magnetic Measurement Results of the LCLS Undulator Quadrupoles

Description: This note details the magnetic measurements and the magnetic center fiducializations that were performed on all of the thirty-six LCLS undulator quadrupoles. Temperature rise, standardization reproducibility, vacuum chamber effects and magnetic center reproducibility measurements are also presented. The Linac Coherent Light Source (LCLS) undulator beam line has 33 girders, each with a LCLS undulator quadrupole which focuses and steers the beam through the beam line. Each quadrupole has main qua… more
Date: August 18, 2011
Creator: Anderson, Scott; Caban, Keith; Nuhn, Heinz-Dieter; Reese, Ed & Wolf, Zachary
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analyzing Ever Growing Datasets in PHENIX

Description: After 10 years of running, the PHENIX experiment has by now accumulated more than 700 TB of reconstructed data which are directly used for analysis. Analyzing these amounts of data efficiently requires a coordinated approach. Beginning in 2005 we started to develop a system for the RHIC Atlas Computing Facility (RACF) which allows the efficient analysis of these large data sets. The Analysis Taxi is now the tool which allows any collaborator to process any data set taken since 2003 in weekly pa… more
Date: October 18, 2010
Creator: Pinkenburg, C. & Collaboration, PHENIX
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reference Undulator Measurement Results

Description: The LCLS reference undulator has been measured 22 times during the course of undulator tuning. These measurements provide estimates of various statistical errors. This note gives a summary of the reference undulator measurements and it provides estimates of the undulator tuning errors. We measured the reference undulator many times during the tuning of the LCLS undulators. These data sets give estimates of the random errors in the tuned undulators. The measured trajectories in the reference und… more
Date: August 18, 2011
Creator: Wolf, Zachary & Levashov, Yurii
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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LARP LHC 4.8 GHZ Schottky System Initial Commissioning with Beam

Description: The LHC Schottky system consists for four independent 4.8 GHz triple down conversion receivers with associated data acquisition systems. Each system is capable of measuring tune, chromaticity, momentum spread in either horizontal or vertical planes; two systems per beam. The hardware commissioning has taken place from spring through fall of 2010. With nominal bunch beam currents of 10{sup 11} protons, the first incoherent Schottky signals were detected and analyzed. This paper will report on th… more
Date: March 18, 2011
Creator: Pasquinelli, Ralph J.; Jansson, Andreas; Jones, O. Rhodri & Caspers, Fritz
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multi-jet Merging with NLO Matrix Elements

Description: In the algorithm presented here, the ME+PS approach to merge samples of tree-level matrix elements into inclusive event samples is combined with the POWHEG method, which includes exact next-to-leading order matrix elements in the parton shower. The advantages of the method are discussed and the quality of its implementation in SHERPA is exemplified by results for e{sup +}e{sup -} annihilation into hadrons at LEP, for deep-inelastic lepton-nucleon scattering at HERA, for Drell-Yan lepton-pair pr… more
Date: August 18, 2011
Creator: Siegert, Frank; Hoche, Stefan; Krauss, Frank & Schonherr, Marek
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of 3D Polarization profiles on polarization measurements and colliding beam experiments

Description: The development of polarization profiles are the primary reason for the loss of average polarization. Polarization profiles have been parametrized with a Gaussian distribution. We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the figure of merit in single and double spin experiments. Examples from RHIC are provided. The Relativistic Heavy Ion Collider (RHIC) is the only collider of spin polarized p… more
Date: August 18, 2011
Creator: Fischer, W. & Bazilevsky, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FERROELECTRIC SWITCH FOR A HIGH-POWER Ka-BAND ACTIVE PULSE COMPRESSOR

Description: Results are presented for design of a high-power microwave switch for operation at 34.3 GHz, intended for use in an active RF pulse compressor. The active element in the switch is a ring of ferroelectric material, whose dielectric constant can be rapidly changed by application of a high-voltage pulse. As envisioned, two of these switches would be built into a pair of delay lines, as in SLED-II at SLAC, so as to allow 30-MW μs-length Ka-band pulses to be compressed in time by a factor-of-9 and m… more
Date: December 18, 2013
Creator: Hirshfield, Jay L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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