NASA Scientific and Technical Aerospace Reports

nominal beam sizes are presented. Applications of these OTR detectors as an on-line emittance monitor for both antiproton
transfers and reverse-injected protons, as a Tevatron injection profile monitor, and as a high-intensity beam profile monitor for
NuMI are discussed. In addition, different types of OTR foils are being evaluated for operation over the intensity range of
(approx)5e9 to 5e13 particles per pulse, and these are described.
NTIS
Antiprotons; Optical Transition; Proton Beams; Protons; Radiation Detectors
20060002229 Jefferson (Thomas) Lab. Computer Center, Newport News, VA, USA
Single Target Spin Asymmetries and GPDs
Chen, J. P.; Jun. 2005; 58 pp.; In English
Report No.(s): DE2005-841872; No Copyright; Avail.: National Technical Information Service (NTIS)
No abstract available
Asymmetry; Mathematical Models; Partons; Targets
20060002332 California Univ., Lawrence Berkeley National Lab., Berkeley, CA, USA
Elimination of ‘Ghost’-Effect-Related Systematic Errors in Metrology of X-ray Optics with a Long Trace Profiler
Yashchuk, V. V.; Irick, S. C.; MacDowell, A. A.; January 2005; 12 pp.; In English
Report No.(s): DE2005-842047; No Copyright; Avail.: Department of Energy Information Bridge
A data acquisition technique and relevant program for suppression of one of the systematic effects, namely the ‘ghost’
effect, of a second generation long trace profiler (LTP) is described. The ‘ghost’ effect arises when there is an unavoidable
cross-contamination of the LTP sample and reference signals into one another, leading to a systematic perturbation in the
recorded interference patterns and, therefore, a systematic variation of the measured slope trace. Perturbations have been
observed with a cylindrically shaped X-ray mirror. Even stronger ‘ghost’ effects show up in an LTP measurement with a mirror
having a toroidal surface figure. The developed technique employs separate measurement of the ‘ghost’-effect-related
interference patterns in the sample and the reference arms and then subtraction of the ‘ghost’ patterns from the sample and
the reference interference patterns. The procedure preserves the advantage of simultaneously measuring the sample and
reference signals. The effectiveness of the technique is illustrated with LTP metrology of a variety of X-ray mirrors.
NTIS
Ghosts; Metrology; Systematic Errors; X Ray Optics
20060002333 Jefferson (Thomas) Lab. Computer Center, Newport News, VA, USA
Single-Spin Beam Asymmetries in QED and QCD
Afanasev, A.; Jun. 03, 2005; 38 pp.; In English
Report No.(s): DE2005-841927; No Copyright; Avail.: National Technical Information Service (NTIS)
No abstract available
Asymmetry; Electron Beams; Quantum Chromodynamics; Quantum Electrodynamics
20060002334 Jefferson (Thomas) Lab. Computer Center, Newport News, VA, USA
Single Spin Asymmetries: from JLab12 to EIC
Avakian, H.; January 2005; 32 pp.; In English
Report No.(s): DE2005-841874; No Copyright; Avail.: National Technical Information Service (NTIS)
No abstract available
Asymmetry; Mathematical Models
20060002335 California Univ., Lawrence Berkeley National Lab., Berkeley, CA, USA
Pyramidal Defects in GaN:Mg Grown with Ga Polarity
Liliental-Weber, Z.; Tomaszewicz, T.; Zakharov, D.; O’Keefe, M. A.; January 2005; 8 pp.; In English
Report No.(s): DE2005-842048; LBNL-57521; No Copyright; Avail.: Department of Energy Information Bridge
Transmission electron microscopy (TEM) studies show formation of different types of Mg-rich defects in GaN. Types of
defects strongly depend on crystal growth polarity. For bulk crystals grown with N-polarity, the planar defects are distributed
at equal distances (20 unit cells of GaN). For growth with Ga-polarity (for both bulk and MOCVD grown crystals) a different
type of defects have been found. These defects are three-dimensional Mg-rich hexagonal pyramids (or trapezoids) with their
base on the (0001) plane and six walls formed on 1123 planes. The defects appear in (1120) and (1100) cross-section TEM
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