NASA Scientific and Technical Aerospace Reports

component of gamma spectra resulting from radiative capture of fast nucleons; i.e., the part of the spectrum that is not
amenable to standard statistical model (Hauser-Feshbach) treatments. We describe recent results on the extension of the DSD
model to unbound final states, including comparison with proton and neutron capture data. The importance of including
convective-current magnetic radiation to explain proton capture angular distributions in the 30 MeV region is shown. We
conclude with a brief discussion of a model closely related to the DSD, the pure-resonance model.
NTIS
Gamma Ray Spectra; Nucleons
74
OPTICS
Includes light phenomena and the theory of optical devices; for specific optical devices see also 35 Instrumentation and Photography.
For lasers see 36 Lasers and Masers.
20040046893 Smithsonian Astrophysical Observatory, Cambridge, MA, USA
Spectroscopic Determination of the Physical Conditions in Hot Optically Thin Sources
Oliversen, Ronald J., Technical Monitor; Brickhouse, Nancy; March 2004; 7 pp.; In English
Contract(s)/Grant(s): NAG5-3559; No Copyright; Avail: CASI; A02, Hardcopy
Astrophysical Plasma Emission Database - APED consists of atomic data, primarily theoretical, needed to calculate X-ray
through optical emission spectra of hot thermal plasmas. These data are supplemented by experimental values, such as
laboratory plasma wave- lengths, and are validated by experiment only rarely. Thus the comparison of predicted spectra to
astrophysical spectra serves as invaluable feedback on the quality of the models. Following up on unfavorable comparisons,
we have communicated atomic data needs to atomic theorists and experimental plasma physicists so that improvements can
be made to the database. The database is now reasonably complete from approx. 1 to 30 A, and from - 90 to 180 A, with
significant gaps remaining in the range 30 to 90 A. Astrophysical Plasma Emission Code - APEC uses the APED data as inputs
and computes level populations and line emissivities using a rate matrix solver. Tabulated models for a fine grid of
temperatures and densities can be applied to observational data. The current public version of APEC output uses an input
ionization balance model, assuming CIE; however, we have a working version to calculate the ionization state of the gas. We
will begin testing non-equilibrium ionization (NEI) models over the next year - we are now finalizing the atomic database
needed to perform the ionization state calculations. At that time, the code will be made public. We have developed optimized
error codes, additional testing protocols and substantial documentation, in preparation for this public release. Secondarily, we
have begun to investigate the use of APED and APEC for X-ray photoionized plasma, beginning with opacity modeling (e.g.
warm absorbers). Application to bright AGN Chandra grating spectra suggests that the accurate wavelengths in APED are of
great importance to fitting the data. We are exploring additional subroutines to APEC to extend its usefulness for X-ray
photoionized plasma, e.g. to include collisional or photo-excitation of metastable levels for absorption.
Derived from text
Spectroscopy; High Temperature Plasmas; Optical Materials; Thin Plates; X Rays; Photoionization
20040046961 Lawrence Livermore National Lab., Livermore, CA
Mechanical Engineering Safety Note - PEPC Spreader Bar Assembly
Mason, D.; Aug. 26, 2001; 50 pp.; In English
Report No.(s): DE2004-15005720; UCRL-ID-145895; No Copyright; Avail: Department of Energy Information Bridge
The PEPC Spreader Bar Assembly consists of a spreader bar that will be attached to the PEPC Cell Housing or the
Midplane Transportation Fixture during operation. While in use in the OAB (Optics Assembly Building), the Spreader Bar
Assembly will be manipulated by the NOID (New Optics Insertion Device). The other critical components of the assembly
are the three angular contact bearing swivels that attach the spreader bar to the lifting mechanism and the corner clamps which
are used to capture the Cell Housing.
NTIS
Mechanical Engineering; Fixtures
20040046967 Lawrence Livermore National Lab., Livermore, CA
Lasershot(sm) Marking System: High-Volume Labeling for Safety-Critical Parts
Dane, C. B.; Hackel, L.; Honig, J.; Halpin, J.; Chen, H. L.; Feb. 16, 2001; 60 pp.; In English
Report No.(s): DE2004-15005707; UCRL-ID-142507; No Copyright; Avail: Department of Energy Information Bridge
185