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in subjects: "Brightness"

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A 4 to 0.1 nm FEL Based on the SLAC Linac

The author show that using existing electron gun technology and a high energy linac like the one at SLAC, it is possible to build a Free Electron Laser operating around the 4 nm water window. A modest improvement in the gun performance would further allow to extend the FEL to the 0.1 nm region. Such a system would produce radiation with a brightness many order of magnitude above that of any synchrotron radiation source, existing or under construction, with laser power in the multigawatt region … more

Date: June 5, 2012

Creator: Pellegrini, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The 8 O'Clock Arc: A Serendipitous Discovery of a Strongly Lensed Lyman Break Galaxy in the SDSS DR4 Imaging Data

We report on the serendipitous discovery of the brightest Lyman Break Galaxy (LBG) currently known, a galaxy at z = 2.73 that is being strongly lensed by the z = 0.38 Luminous Red Galaxy (LRG) SDSS J002240.91+143110.4. The arc of this gravitational lens system, which we have dubbed the ''8 o'clock arc'' due to its time of discovery, was initially identified in the imaging data of the Sloan Digital Sky Survey Data Release 4 (SDSS DR4); followup observations on the Astrophysical Research Consorti… more

Date: November 1, 2006

Creator: Allam, Sahar S.; Tucker, Douglas L.; Lin, Huan; Diehl, H. Thomas; Annis, James; Buckley-Geer, Elizabeth J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

20-100 keV K(alpha) X-Ray Source Generation by Short Pulse High Intensity Lasers

We are studying the feasibility of utilizing K{alpha} x-ray sources in the range of 20 to 100 keV as a backlighters for imaging various stages of implosions and high areal density planar samples driven by the NIF laser facility. The hard x-ray K{alpha} sources are created by relativistic electron plasma interactions in the target material after a radiation by short pulse high intensity lasers. In order to understand K{alpha} source characteristics such as production efficiency and brightness as… more

Date: August 22, 2003

Creator: Park, H. S.; Koch, J. A.; Landen, O. L.; Phillips, T. W. & Goldsack, T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

20 keV undulators for a 6-GeV storage ring

The main goal of the future 6-GeV electron storage ring is to provide 20-keV fundamental harmonic radiations from insertion devices. Parameter restrictions of REC-vanadium permendur hybrid undulators have been examined. The critical factor is the achievable minimum gap of the undulator. Variations of the spectral brilliance for different beam parameters are also shown. 6 refs., 5 figs.

Date: January 1, 1985

Creator: Kim, S. H. & Cho, Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A 20-year data set of surface longwave fluxes in the Arctic

Creation of 20-year data set of surface infrared fluxes from satellite measurements. A reliable estimate of the surface downwelling longwave radiation flux (DLF) is a glaring void in available forcing data sets for models of Arctic sea ice and ocean circulation. We have developed a new method to estimate the DLF from a combination of satellite sounder retrievals and brightness temperatures from the TIROS Operational Vertical Sounder (TOVS), which has flown on NOAA polar-orbiting satellites cont… more

Date: June 15, 2004

Creator: Francis, Jennifer

Item Type: Report

Partner: UNT Libraries Government Documents Department

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183-GHz Radiometer Handbook - November 2006

The G-Band Vapor Radiometer (GVR) provides time-series measurements of brightness temperatures from four double sideband channels centered at ± 1, ± 3, ± 7, and ± 14 GHz around the 183.31-GHz water vapor line. Atmospheric emission in this spectral region is primarily due to water vapor, with some influence from liquid water. The 183.31 ± 14-GHz channel is particularly sensitive to the presence of liquid water. The sensitivity to water vapor of the 183.31-GHz line is approximately 30 times highe… more

Date: November 30, 2006

Creator: Cadeddu, M. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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The 300 Kpc Long X-Ray Jet in PKS 1127-145, Z=1.18 Quasar: Constraining X-Ray Emission Models

We present a {approx} 100 ksec Chandra X-ray observation and new VLA radio data of the large scale, 300 kpc long X-ray jet in PKS 1127-145, a radio loud quasar at redshift z=1.18. With this deep X-ray observation we now clearly discern the complex X-ray jet morphology and see substructure within the knots. The X-ray and radio jet intensity profiles are seen to be strikingly different with the radio emission peaking strongly at the two outer knots while the X-ray emission is strongest in the inn… more

Date: November 20, 2006

Creator: Siemiginowska, Aneta; Stawarz, Lukasz; Cheung, C. C.; Harris, D. E.; Sikora, Marek; Aldcroft, Thomas L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

600 eV falcon-linac thomson x-ray source

The advent of 3rd generation light sources such as the Advanced Light Source (ALS) at LBL, and the Advanced Photon Source at Argonne, have produced a revolution in x-ray probing of dense matter during the past decade. These machines use electron-synchrotrons in conjunction with undulator stages to produce 100 psec x-ray pulses with photon energies of several kiloelectronvolts (keV). The applications for x-ray probing of matter are numerous and diverse with experiments in medicine and biology, s… more

Date: December 15, 2000

Creator: Crane, J. K.; LeSage, G. P.; Ditmire, T.; Cross, R.; Wharton, K.; Moffitt, K. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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12th Advanced Accelerator Concept (AAC 2006) Workshop

Summary of the 12th Advanced Accelerator Concept (AAC 2006) Workshop help by NIU and ANL on July 10th-15th 2006 in Lake Geneva WI. The proceedings of the workshop have been published as an AIP conference proceedings "12th Advanced Accelerator Concepts Workshop” volume 877.

Date: July 15, 2006

Creator: Piot, Philippe

Item Type: Text

Partner: UNT Libraries Government Documents Department

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A 3D Parallel Beam Dynamics Code for Modeling High Brightness Beams in Photoinjectors

In this paper we report on IMPACT-T, a 3D beam dynamics code for modeling high brightness beams in photoinjectors and rf linacs. IMPACT-T is one of the few codes used in the photoinjector community that has a parallel implementation, making it very useful for high statistics simulations of beam halos and beam diagnostics. It has a comprehensive set of beamline elements, and furthermore allows arbitrary overlap of their fields. It is unique in its use of space-charge solvers based on an integrat… more

Date: February 13, 2006

Creator: Qiang, Ji; Lidia, S.; Ryne, R.D. & Limborg, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A 3d Parallel Beam Dynamics Code for Modeling High BrightnessBeams in Photoinjectors

Date: May 16, 2005

Creator: Qiang, J.; Lidia, S.; Ryne, R. & Limborg, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

7th ICFA mini-workshop on high intensity high brightness hadron beams

No Description Available.

Date: October 10, 2000

Creator: Mokhov, Nikolai V. & Chou, Weiren

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Absolute X-Ray Yields From Laser-Irradiated, Ge-Doped Aerogel Targets

Bright, multi-keV x-ray sources are essential for radiography of inertial-confinement fusion (ICF) experiments. In this context, there are two parameters of importance: the energy of the emitted photons, which determines how penetrating the x-rays are for radiographic purposes, and the brightness of the source, which determines the ability of a radiograph to resolve small features. As ICF experiments continue to get larger, such as those that will be carried out at the National Ignition Facilit… more

Date: June 15, 2005

Creator: Fournier, K. B.; Tobin, M.; Poco, J. F.; Bradley, K.; Coverdale, C. A.; Beutler, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Accelerator based coal positron beams

Cold positron beams produced using solid state moderators have been used profitably for condensed matter and positronium research. The low emittance and energy spread of these beams make the technique attractive as a potential positron source for future linear colliders, reducing or eliminating the need for damping rings. However, the intensities attained so far fall short of the requirements of a high energy linear collider. (approx.10/sup 11/ positrons/pulse at 10 kHz was taken as the positro… more

Date: January 1, 1987

Creator: Schoessow, P. & Simpson, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Accomplishments Achieved Under DOE Grant Number DE-FG03-92ER40693: The Physics of Gain Mechanisms in Self-Amplified Spontaneous Emission in Free Electron Lasers

No Description Available.

Date: February 5, 2007

Creator: Rosenzweig, James

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Achieving Stability Requirements for Nanoprobe and Long Beam Lines at NSLS II. A Comprehensive Study

Driven by beam stability requirements at the NSLS II synchrotron, such that the desired small beam sizes and high brightness are both realized and stable, a comprehensive study has been launched seeking to provide assurances that stability at the nanometer level at critical x-ray beam-lines, is achievable, given the natural and cultural vibration environment at the selected site. The study consists of (a) an extensive investigation of the site to evaluate the existing ground vibration, in terms… more

Date: June 23, 2008

Creator: Simos,N.; Fallier, M.; Hill, J.; Berman, L.; Evans-Lutterodt, K. & Broadbent, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

ADDITIONAL QUADRUPOLES AT CENTER OF LONG STRAIGHTS IN THE NSLS-II LATTICE

The NSLS-II storage ring lattice is comprised of 30 DBA cells arranged in 15 superperiods. There are 15 long straight sections (9.3m) for injection, RF and insertion devices and 15 shorter straights (6.6m) for insertion devices. In the baseline lattice, the short straights have small horizontal and vertical beta functions but the long straights have large horizontal beta function optimized for injection. In this paper, we explore the possibility of installing additional quadrupoles at the cente… more

Date: March 28, 2011

Creator: Lin, F.; Bengtsson, J.; Guo, W.; Krinsky, S.; Li, Y. & Yang, L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Adjusted Field Profile for the Chromaticity Cancellation in FFAG Accelerators.

In an earlier report they have reviewed four major rules to design the lattice of Fixed-Field Alternating-Gradient (FFAG) accelerators. One of these rules deals with the search of the Adjusted Field Profile, that is the field non-linear distribution along the length and the width of the accelerator magnets, to compensate for the chromatic behavior, and thus to reduce considerably the variation of betatron tunes during acceleration over a large momentum range. The present report defines the meth… more

Date: October 13, 2004

Creator: Ruggiero, A. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Advanced 3D Photocathode Modeling and Simulations Final Report

High brightness electron beams required by the proposed Next Linear Collider demand strong advances in photocathode electron gun performance. Significant improvement in the production of such beams with rf photocathode electron guns is hampered by the lack high-fidelity simulations. The critical missing piece in existing gun codes is a physics-based, detailed treatment of the very complex and highly nonlinear photoemission process.

Date: June 6, 2005

Creator: Dimitrov, Dimitre A. & Bruhwiler, David L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Advanced Compton scattering light source R&D at LLNL

We report the design and current status of a monoenergetic laser-based Compton scattering 0.5-2.5 MeV {gamma}-ray source. Previous nuclear resonance fluorescence results and future linac and laser developments for the source are presented. At MeV photon energies relevant for nuclear processes, Compton scattering light sources are attractive because of their relative compactness and improved brightness above 100 keV, compared to typical 4th generation synchrotrons. Recent progress in accelerator… more

Date: February 16, 2010

Creator: Albert, F.; Anderson, S. G.; Anderson, G.; Betts, S. M.; Chu, T. S.; Gibson, D. J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Advanced Diagnostics for Developing High-Brightness Electron Beams.

The production of high-brightness particle beams calls for the development of advanced beam diagnostics. High brightness beams, meaning beams with a high density in phase space, are important for many applications, such as short-wavelength Free-Electron Lasers and advanced accelerator systems. A diagnostic that provides detailed information on the density distribution of the electron bunch in multi-dimensional phase-space is an essential tool for obtaining small emittance at a high charge. This… more

Date: November 24, 1998

Creator: Ben-Zvi, Ilan

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Advanced Light Source: A third-generation Synchrotron Radiation Source

The Advanced Light Source (ALS) at the E.O. Lawrence Berkeley National Laboratory (Berkeley Lab) of the University of California is a ''third-generation'' synchrotron radiation source optimized for highest brightness at ultraviolet and soft x-ray photon energies. It also provides world-class performance at hard x-ray photon energies. Berkeley Lab operates the ALS for the United States Department of Energy as a national user facility that is available 24 hours/day around the year for research by… more

Date: August 14, 2002

Creator: Robinson, Arthur L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The Advanced Light Source Upgrade

The ALS, a third-generation synchrotron light source at Berkeley Lab, has been operating for almost a decade and is generating forefront science by exploiting the high brightness of a third-generation source in three areas: (1) high resolving power for spectroscopy; (2) high spatial resolution for microscopy and spectromicroscopy; and (3) high coherence for experiments such as speckle. However, the ALS was one of the first third-generation machines to be designed, and accelerator and insertion-… more

Date: November 4, 2003

Creator: Chemla, Daniel S.; Feinberg, Benjamin; Hussain, Zahid; Krebs, Gary F.; Padmore, Howard A.; Robin, David S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

ADVANCED X-BAND TEST ACCELERATOR FOR HIGH BRIGHTNESS ELECTRON AND GAMMA RAY BEAMS

In support of Compton scattering gamma-ray source efforts at LLNL, a multi-bunch test stand is being developed to investigate accelerator optimization for future upgrades. This test stand will enable work to explore the science and technology paths required to boost the current 10 Hz monoenergetic gamma-ray (MEGa-Ray) technology to an effective repetition rate exceeding 1 kHz, potentially increasing the average gamma-ray brightness by two orders of magnitude. Multiple bunches must be of exceedi… more

Date: May 12, 2010

Creator: Marsh, R A; Anderson, S G; Barty, C P; Chu, T S; Ebbers, C A; Gibson, D J et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department