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Beyond Spin-Orbit: Probing Electron Correlation in the Pu 5f States

Description: Experiments planned to address the issue of electron correlation in the Pu 5f states are described herein. The key is the utilization of the Fano Effect, the observation of spin polarization in nonmagnetic systems, using chiral excitation such as circularly polarized X-rays.
Date: May 8, 2006
Creator: Tobin, J G
Partner: UNT Libraries Government Documents Department
open access

Probing the spin polarization of current by soft x-ray imaging of current-induced magnetic vortex dynamics

Description: Time-resolved soft X-ray transmission microscopy is applied to image the current-induced resonant dynamics of the magnetic vortex core realized in a micron-sized Permalloy disk. The high spatial resolution better than 25 nm enables us to observe the resonant motion of the vortex core. The result also provides the spin polarization of the current to be 0.67 {+-} 0.16 for Permalloy by fitting the experimental results with an analytical model in the framework of the spin-transfer torque.
Date: December 9, 2008
Creator: Kasai, Shinya; Fischer, Peter; Im, Mi-Young; Yamada, Keisuke; Nakatani, Yoshinobu; Kobayashi, Kensuke et al.
Partner: UNT Libraries Government Documents Department
open access

A comparison between Gauss-Newton and Markov chain Monte Carlo basedmethods for inverting spectral induced polarization data for Cole-Coleparameters

Description: We develop a Bayesian model to invert spectral induced polarization (SIP) data for Cole-Cole parameters using Markov chain Monte Carlo (MCMC) sampling methods. We compare the performance of the MCMC based stochastic method with an iterative Gauss-Newton based deterministic method for Cole-Cole parameter estimation through inversion of synthetic and laboratory SIP data. The Gauss-Newton based method can provide an optimal solution for given objective functions under constraints, but the obtained… more
Date: May 15, 2008
Creator: Chen, Jinsong; Kemna, Andreas & Hubbard, Susan S.
Partner: UNT Libraries Government Documents Department
open access

20% Partial Siberian Snake in the AGS.

Description: An 11.4% partial Siberian snake was used to successfully accelerate polarized proton through a strong intrinsic depolarizing spin resonance in the AGS. No noticeable depolarization was observed. This opens up the possibility of using a 20% to 30% partial Siberian snake in the AGS to overcome all weak and strong depolarizing spin resonances. Some design and operation issues of the new partial Siberian snake are discussed.
Date: November 6, 2002
Creator: Huang, H.; Bai, M.; Brown, K. A.; Glenn, W.; Luccio, A. U.; MacKay, W. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Probing Ferroelectricity in PbZr0.2Ti0.8O3 with Polarized Soft X-rays

Description: The reduction in symmetry associated with the onset of ferroelectric order in PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} (PZT) thin films leads to a pronounced difference at the Ti L{sub 3,2} absorption edges between spectra measured with the x-ray linear polarization perpendicular and parallel to the ferroelectric polarization. We introduce a general method to analyze the observed difference spectra using atomic multiplet calculations. Moreover, we find experimental evidence for structural changes in PZ… more
Date: June 7, 2010
Creator: Arenholz, E.; van der Laan, G.; Fraile-Rodriguez, A.; Yu, P.; He, Q. & Ramesh, R.
Partner: UNT Libraries Government Documents Department
open access

Magnetically-induced electric polarization in an organo-metallic magnet

Description: The coupling between magnetic order and ferroelectricity has been under intense investigation in a wide range of transition metal oxides. The strongest coupling is obtained in so-called magnetically induced multiferroics where ferroelectricity arises directly from magnetic order that breaks inversion symmetry. However, it has been difficult to find non-oxide based materials in which these effects occur. Here we present a study of copper dimethyl sulfoxide dichloride (CDC), an organometallic qua… more
Date: January 1, 2009
Creator: Zapf, W. S.; Fabris, F. W.; Balakirev, F. F.; Francoual, S. M.; Kenzelmann, M. & Chen, Y.
Partner: UNT Libraries Government Documents Department
open access

Science Drivers and Technical Challenges for Advanced Magnetic Resonance

Description: This report recaps the "Science Drivers and Technical Challenges for Advanced Magnetic Resonance" workshop, held in late 2011. This exploratory workshop's goal was to discuss and address challenges for the next generation of magnetic resonance experimentation. During the workshop, participants from throughout the world outlined the science drivers and instrumentation demands for high-field dynamic nuclear polarization (DNP) and associated magnetic resonance techniques, discussed barriers to the… more
Date: March 7, 2013
Creator: Mueller, Karl T.; Pruski, Marek; Washton, Nancy M. & Lipton, Andrew S.
Partner: UNT Libraries Government Documents Department
open access

Spin Tracking Studies for Beam Polarization Preservation in theNLC Main Damping Rings

Description: We report results from studies of spin dynamics in the NLC Main Damping. Our studies have been based on spin tracking particles through the lattice under a range of conditions. We find that there are a number of spin resonances close to the nominal operating energy of 1.98 GeV; however, the effects of the resonances are weak, and the widths are narrow. We do not expect that any significant depolarization of the beam will occur during the store time.
Date: July 26, 2004
Creator: Wolski, Andrzej & Bates, Daniel
Partner: UNT Libraries Government Documents Department
open access

The Mechanism of Proton Polarization in High-EnergyCollisions

Description: Recently experimental evidence has accumulated showing that high-energy collisions of protons with various nuclei induce a considerable polarization in proton beams, and a mechanism has been proposed to account for this effect.
Date: June 9, 1954
Creator: Chamberlain, Owen; Segre, Emilio; Tripp, Robert; Wiegand, Clyde & Ypsilantis, Thomas
Partner: UNT Libraries Government Documents Department
open access

Polarized light propagation through tissue and tissue phantoms

Description: We show that standard tissue phantoms can be used to mimic the intensity and polarization properties of tissue. Polarized light propagation through biologic tissue is typically studied using tissue phantoms consisting of dilute aqueous suspensions of microspheres. The dilute phantoms can empirically match tissue polarization and intensity properties. One discrepancy between the dilute phantoms and tissue exist: common tissue phantoms, such as dilute Intralipid and dilute 1-{micro}m-diameter pol… more
Date: February 8, 2000
Creator: Sankaran, V; Walsh, J T JR & Maitland, D J
Partner: UNT Libraries Government Documents Department
open access

Endoscopic subsurface imaging in tissues

Description: The objective of this work is to develop endoscopic subsurface optical imaging technology that will be able to image different tissue components located underneath the surface of the tissue at an imaging depth of up to 1 centimeter. This effort is based on the utilization of existing technology and components developed for medical endoscopes with the incorporation of the appropriate modifications to implement the spectral and polarization difference imaging technique. This subsurface imaging te… more
Date: February 12, 2001
Creator: Demos, S G; Staggs, M & Radousky, H B
Partner: UNT Libraries Government Documents Department
open access

The effect of laser shock peening with and without protective coating on intergranular corrosion of sensitized AA5083

Description: Article applies Laser Shock Peening with (LSP) and without protective coating (LPwC) to sensitized AA5083 followed by electrochemical analysis.
Date: November 1, 2021
Creator: Kaufman, Jan; Racek, Jan; Cieslar, Miroslav; Minárik, Peter; Steiner, Matthew A.; Mannava, Seetha R. et al.
Partner: UNT College of Engineering
open access

Efficient Coupling of 527 nm Laser Beam Power to a Long Scalelength Plasma

Description: We experimentally demonstrate that application of laser smoothing schemes including smoothing by spectral dispersion (SSD) and polarization smoothing (PS) increases the intensity range for efficient coupling of frequency doubled (527 nm) laser light to a long scalelength plasma with n{sub e}/n{sub cr} = 0.14 and T{sub e} = 2 keV.
Date: August 24, 2005
Creator: Moody, J. D.; Divol, L.; Glenzer, S. H.; MacKinnon, A. J.; Froula, D. H.; Gregori, G. et al.
Partner: UNT Libraries Government Documents Department
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Handbook of Accelerator Physics and Engineering (sections 2.7.1 - 2.7.5 and 7.6.2)

Description: The sections written by this author are: 2.7.1- Thomas - BMT equation; 2.2.2- Spinor Algebra; 2.7.3- Spin Rotators and Siberian Snakes; 2.7.4- Ring with Spin Rotator and Siberian Snakes; 2.7.5- Depolarizing Resonances and Spin Flippers; & 7.6.2- Proton Beam Polarimeters
Date: April 19, 1999
Creator: Roser, T.
Partner: UNT Libraries Government Documents Department
open access

Acceleration of Polarized Protons to Relativistic Energies

Description: Maintenance of polarization of polarized protons in a linear accelerator is known to be feasible. Circular accelerators present a different problem, and the investigation of the interaction of orbit dynamics and particle polarization in general is undertaken. The equation of motion of the spin vector of a charged particle in a magnetic field as formulated by Bargmann, Michel, and Telegdi is utilized in the study of depolarization for several accelerators. High values of depolarization are obtai… more
Date: January 22, 1962
Creator: Courant, E.D.
Partner: UNT Libraries Government Documents Department
open access

HIGH ENERGY HADRON POLARIMETRY.

Description: Proton polarimetry at RHIC uses the interference of electromagnetic (EM) and hadronic scattering amplitudes. The EM spin-flip amplitude for protons is responsible for the proton's anomalous magnetic moment, and is large. This then generates a significant analyzing power for small angle elastic scattering. RHIC polarimetry has reached a 5% uncertainty on the beam polarization, and seem capable of reducing this uncertainty further. Polarized neutron beams ax also interesting for RHIC and for a po… more
Date: September 10, 2007
Creator: BUNCE,G.
Partner: UNT Libraries Government Documents Department
open access

VCSEL polarization control for chip-scale atomic clocks.

Description: Sandia National Laboratories and Mytek, LLC have collaborated to develop a monolithically-integrated vertical-cavity surface-emitting laser (VCSEL) assembly with controllable polarization states suitable for use in chip-scale atomic clocks. During the course of this work, a robust technique to provide polarization control was modeled and demonstrated. The technique uses deeply-etched surface gratings oriented at several different rotational angles to provide VCSEL polarization stability. A rigo… more
Date: January 1, 2007
Creator: Geib, Kent Martin; Peake, Gregory Merwin; Wendt, Joel Robert; Serkland, Darwin Keith & Keeler, Gordon Arthur
Partner: UNT Libraries Government Documents Department
open access

Anti-Hyperon polarization in high energy pp collisions withpolarized beams

Description: We study the longitudinal polarization of the {bar {Sigma}}{sup -}, {bar {Sigma}}{sup +}, {bar {Xi}}{sup 0} and {bar {Xi}}{sup +} anti-hyperons in polarized high energy pp collisions at large transverse momenta, extending a recent study for the {bar {Lambda}} antihyperon. We make predictions by using different parameterizations of the polarized parton densities and models for the polarized fragmentation functions. Similar to the {bar {Lambda}} polarization, the {bar {Xi}}{sup 0} and {bar {Xi}}{… more
Date: November 20, 2007
Creator: Chen, Ye; Liang, Zuo-tang; Sichtermann, Ernst; Xu, Qing-hua & Zhou, Shan-shan
Partner: UNT Libraries Government Documents Department
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