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44 results on '"Wittman, M. D."'

1. Causes of fuel–ablator mix inferred from modeling of monochromatic time-gated radiography of OMEGA cryogenic implosions

Author

Collins, T. J. B., primary, Stoeckl, C., additional, Epstein, R., additional, Bittle, W. A., additional, Forrest, C. J., additional, Glebov, V. Yu., additional, Goncharov, V. N., additional, Harding, D. R., additional, Hu, S. X., additional, Jacobs-Perkins, D. W., additional, Kosc, T. Z., additional, Marozas, J. A., additional, Mileham, C., additional, Marshall, F. J., additional, Morse, S. F. B., additional, Radha, P. B., additional, Regan, S. P., additional, Rice, B., additional, Sangster, T. C., additional, Shoup, M. J., additional, Shmayda, W. T., additional, Sorce, C., additional, Theobald, W., additional, and Wittman, M. D., additional

Published
2022
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2. Enhanced laser-energy coupling with small-spot distributed phase plates (SG5-650) in OMEGA DT cryogenic target implosions

Author

Theobald, W., primary, Cao, D., additional, Shah, R. C., additional, Thomas, C. A., additional, Igumenshchev, I. V., additional, Bauer, K. A., additional, Betti, R., additional, Bonino, M. J., additional, Campbell, E. M., additional, Christopherson, A. R., additional, Churnetski, K., additional, Edgell, D. H., additional, Forrest, C. J., additional, Frenje, J. A., additional, Gatu Johnson, M., additional, Glebov, V. Yu., additional, Goncharov, V. N., additional, Gopalaswamy, V., additional, Harding, D. R., additional, Hu, S. X., additional, Ivancic, S. T., additional, Jacobs-Perkins, D. W., additional, Janezic, R. T., additional, Joshi, T., additional, Knauer, J. P., additional, Lees, A., additional, Luo, R. W., additional, Mannion, O. M., additional, Marshall, F. J., additional, Mohamed, Z. L., additional, Morse, S. F. B., additional, Patel, D., additional, Peebles, J. L., additional, Petrasso, R. D., additional, Radha, P. B., additional, Rinderknecht, H. G., additional, Rosenberg, M. J., additional, Sampat, S., additional, Sangster, T. C., additional, Shmayda, W. T., additional, Shuldberg, C. M., additional, Shvydky, A., additional, Sorce, C., additional, Stoeckl, C., additional, Wittman, M. D., additional, and Regan, S. P., additional

Published
2022
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4. The National Direct-Drive Program: OMEGA to the National Ignition Facility

Author

Regan, S. P., primary, Goncharov, V. N., additional, Sangster, T. C., additional, Campbell, E. M., additional, Betti, R., additional, Anderson, K. S., additional, Bernat, T., additional, Bose, A., additional, Boehly, T. R., additional, Bonino, M. J., additional, Cao, D., additional, Chapman, R., additional, Collins, T. J. B., additional, Craxton, R. S., additional, Davis, A. K., additional, Delettrez, J. A., additional, Edgell, D. H., additional, Epstein, R., additional, Farrell, M., additional, Forrest, C. J., additional, Frenje, J. A., additional, Froula, D. H., additional, Johnson, M. Gatu, additional, Gibson, C., additional, Glebov, V. Yu., additional, Greenwood, A., additional, Harding, D. R., additional, Hohenberger, M., additional, Hu, S. X., additional, Huang, H., additional, Hund, J., additional, Igumenshchev, I. V., additional, Jacobs-Perkins, D. W., additional, Janezic, R. T., additional, Karasik, M., additional, Keck, R. L., additional, Kelly, J. H., additional, Kessler, T. J., additional, Knauer, J. P., additional, Kosc, T. Z., additional, Loucks, S. J., additional, Marozas, J. A., additional, Marshall, F. J., additional, McCrory, R. L., additional, McKenty, P. W., additional, Meyerhofer, D. D., additional, Michel, D. T., additional, Myatt, J. F., additional, Obenschain, S. P., additional, Petrasso, R. D., additional, Petta, N., additional, Radha, P. B., additional, Rosenberg, M. J., additional, Schmitt, A. J., additional, Schmitt, M. J., additional, Schoff, M., additional, Seka, W., additional, Shmayda, W. T., additional, Shoup, M. J., additional, Shvydky, A., additional, Solodov, A. A., additional, Stoeckl, C., additional, Sweet, W., additional, Taylor, C., additional, Taylor, R., additional, Theobald, W., additional, Ulreich, J., additional, Wittman, M. D., additional, Woo, K. M., additional, and Zuegel, J. D., additional

Published
2017
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6. Effect of experimentally observed hydrogenic fractionation on inertial confinement fusion ignition target performance.

Author

McKenty, P. W., Wittman, M. D., and Harding, D. R.

Subjects
*INERTIAL confinement fusion, *ADIABATIC engines, *HYDROGEN, *LOW temperature engineering, *DEUTERIUM, *TRITIUM
Abstract

The need of cryogenic hydrogenic fuels in inertial confinement fusion (ICF) ignition targets has been long been established. Efficient implosion of such targets has mandated keeping the adiabat of the main fuel layer at low levels to ensure drive energies are kept at reasonable minima. The use of cryogenic fuels helps meet this requirement and has therefore become the standard in most ICF ignition designs. To date most theoretical ICF ignition target designs have assumed a homogeneous layer of deuterium-tritium (DT) fuel kept slightly below the triple point. However, recent work has indicated that, as cryogenic fuel layers are formed inside an ICF capsule, isotopic dissociation of the tritium (T), deuterium (D), and DT takes place leading to a “fractionation” of the final ice layer. This paper will numerically investigate the effects that various scenarios of fractionation have on hot-spot formation, ignition, and burn in ICF ignition target designs. [ABSTRACT FROM AUTHOR]

Published
2006
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7. Characterization of thick cryogenic fuel layers using convergent-beam interferometry: A numerical investigation.

Author

McKenty, P. W., Wittman, M. D., and Goncharov, V. N.

Subjects
*INERTIAL confinement fusion, *INTERFEROMETERS
Abstract

Describes a method to interferometrically characterize the inner surface of an inertial confinement fusion (ICF) capsule. Features of the convergent-beam Mach-Zehnder interferometer; Method to decompose the wavefronts into a one-dimensional Fourier spectrum; Validity of convergent-beam interferometry by analyzing numerically generated perturbed wavefronts.

Published
2000
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8. Demonstration of Fuel Hot-Spot Pressure in Excess of 50 Gbar for Direct-Drive, Layered Deuterium-Tritium Implosions on OMEGA

Author

Massachusetts Institute of Technology. Plasma Science and Fusion Center, Petrasso, Richard D, Regan, S. P., Goncharov, V. N., Igumenshchev, I. V., Sangster, T. C., Betti, R., Bose, A., Boehly, T. R., Bonino, M. J., Campbell, E. M., Cao, D., Collins, T. J. B., Craxton, R. S., Davis, A. K., Delettrez, J. A., Edgell, D. H., Epstein, R., Forrest, C. J., Frenje, J. A., Froula, D. H., Gatu Johnson, M., Glebov, V. Yu., Harding, D. R., Hohenberger, M., Hu, S. X., Jacobs-Perkins, D., Janezic, R., Karasik, M., Keck, R. L., Kelly, J. H., Kessler, T. J., Knauer, J. P., Kosc, T. Z., Loucks, S. J., Marozas, J. A., Marshall, F. J., McCrory, R. L., McKenty, P. W., Meyerhofer, D. D., Michel, D. T., Myatt, J. F., Obenschain, S. P., Radha, P. B., Rice, B., Rosenberg, M. J., Schmitt, A. J., Schmitt, M. J., Seka, W., Shmayda, W. T., Shoup, M. J., Shvydky, A., Skupsky, S., Solodov, A. A., Stoeckl, C., Theobald, W., Ulreich, J., Wittman, M. D., Woo, K. M., Yaakobi, B., Zuegel, J. D., Massachusetts Institute of Technology. Plasma Science and Fusion Center, Petrasso, Richard D, Regan, S. P., Goncharov, V. N., Igumenshchev, I. V., Sangster, T. C., Betti, R., Bose, A., Boehly, T. R., Bonino, M. J., Campbell, E. M., Cao, D., Collins, T. J. B., Craxton, R. S., Davis, A. K., Delettrez, J. A., Edgell, D. H., Epstein, R., Forrest, C. J., Frenje, J. A., Froula, D. H., Gatu Johnson, M., Glebov, V. Yu., Harding, D. R., Hohenberger, M., Hu, S. X., Jacobs-Perkins, D., Janezic, R., Karasik, M., Keck, R. L., Kelly, J. H., Kessler, T. J., Knauer, J. P., Kosc, T. Z., Loucks, S. J., Marozas, J. A., Marshall, F. J., McCrory, R. L., McKenty, P. W., Meyerhofer, D. D., Michel, D. T., Myatt, J. F., Obenschain, S. P., Radha, P. B., Rice, B., Rosenberg, M. J., Schmitt, A. J., Schmitt, M. J., Seka, W., Shmayda, W. T., Shoup, M. J., Shvydky, A., Skupsky, S., Solodov, A. A., Stoeckl, C., Theobald, W., Ulreich, J., Wittman, M. D., Woo, K. M., Yaakobi, B., and Zuegel, J. D.

Abstract

A record fuel hot-spot pressure P[subscript hs] = 56±7 Gbar was inferred from x-ray and nuclear diagnostics for direct-drive inertial confinement fusion cryogenic, layered deuterium–tritium implosions on the 60-beam, 30-kJ, 351-nm OMEGA Laser System. When hydrodynamically scaled to the energy of the National Ignition Facility, these implosions achieved a Lawson parameter ∼60% of the value required for ignition [A. Bose et al., Phys. Rev. E 93, LM15119ER (2016)], similar to indirect-drive implosions [R. Betti et al., Phys. Rev. Lett. 114, 255003 (2015)], and nearly half of the direct-drive ignition-threshold pressure. Relative to symmetric, one-dimensional simulations, the inferred hot-spot pressure is approximately 40% lower. Three-dimensional simulations suggest that low-mode distortion of the hot spot seeded by laser-drive nonuniformity and target-positioning error reduces target performance., United States. Department of Energy (DE-NA0001944)

Published
2017

10. Monochromatic backlighting of direct-drive cryogenic DT implosions on OMEGA

Author

Stoeckl, C., primary, Epstein, R., additional, Betti, R., additional, Bittle, W., additional, Delettrez, J. A., additional, Forrest, C. J., additional, Glebov, V. Yu., additional, Goncharov, V. N., additional, Harding, D. R., additional, Igumenshchev, I. V., additional, Jacobs-Perkins, D. W., additional, Janezic, R. T., additional, Kelly, J. H., additional, Kosc, T. Z., additional, McCrory, R. L., additional, Michel, D. T., additional, Mileham, C., additional, McKenty, P. W., additional, Marshall, F. J., additional, Morse, S. F. B., additional, Regan, S. P., additional, Radha, P. B., additional, Rice, B., additional, Sangster, T. C., additional, Shoup, M. J., additional, Shmayda, W. T., additional, Sorce, C., additional, Theobald, W., additional, Ulreich, J., additional, Wittman, M. D., additional, Meyerhofer, D. D., additional, Frenje, J. A., additional, Gatu Johnson, M., additional, and Petrasso, R. D., additional

Published
2017
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11. Demonstration of Fuel Hot-Spot Pressure in Excess of 50 Gbar for Direct-Drive, Layered Deuterium-Tritium Implosions on OMEGA

Author

Regan, S. P., primary, Goncharov, V. N., additional, Igumenshchev, I. V., additional, Sangster, T. C., additional, Betti, R., additional, Bose, A., additional, Boehly, T. R., additional, Bonino, M. J., additional, Campbell, E. M., additional, Cao, D., additional, Collins, T. J. B., additional, Craxton, R. S., additional, Davis, A. K., additional, Delettrez, J. A., additional, Edgell, D. H., additional, Epstein, R., additional, Forrest, C. J., additional, Frenje, J. A., additional, Froula, D. H., additional, Gatu Johnson, M., additional, Glebov, V. Yu., additional, Harding, D. R., additional, Hohenberger, M., additional, Hu, S. X., additional, Jacobs-Perkins, D., additional, Janezic, R., additional, Karasik, M., additional, Keck, R. L., additional, Kelly, J. H., additional, Kessler, T. J., additional, Knauer, J. P., additional, Kosc, T. Z., additional, Loucks, S. J., additional, Marozas, J. A., additional, Marshall, F. J., additional, McCrory, R. L., additional, McKenty, P. W., additional, Meyerhofer, D. D., additional, Michel, D. T., additional, Myatt, J. F., additional, Obenschain, S. P., additional, Petrasso, R. D., additional, Radha, P. B., additional, Rice, B., additional, Rosenberg, M. J., additional, Schmitt, A. J., additional, Schmitt, M. J., additional, Seka, W., additional, Shmayda, W. T., additional, Shoup, M. J., additional, Shvydky, A., additional, Skupsky, S., additional, Solodov, A. A., additional, Stoeckl, C., additional, Theobald, W., additional, Ulreich, J., additional, Wittman, M. D., additional, Woo, K. M., additional, Yaakobi, B., additional, and Zuegel, J. D., additional

Published
2016
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12. Effect of Tritium-Induced Damage on Plastic Targets from High-Density DT Permeation

Author

Wittman, M. D., Bonino, M. J., Edgell, D. H., Fella, C., Harding, D. R., and Sanchez, J.

Abstract

AbstractDirect-drive inertial fusion experiments conducted at the Laboratory for Laser Energetics implode 860-μm-diameter, 8-μm-thick glow-discharge polymer (GDP) capsules that have a solid, uniform, 60- to 80-μm-thick layer of an equimolar mixture of deuterium and tritium (DT) on their interior. The DT is permeated through the capsule’s wall up to pressures of 1000 atm in small pressure steps to prevent buckling; this occurs over many hours. The capsule is then cooled, the DT is solidified, and the uniform layer is formed using thermal gradients produced by heat deposited from beta decay of the tritium. Thermal contraction of the capsule from cooling is expected to be ~1% of the diameter. Capsules permeated with DT do not exhibit this contraction and retain their room-temperature diameter after cooling. Sources of error in the imaging system were explored, and a systematic 3 μm over measurement of the diameter was revealed and corrected. However, both GDP capsules permeated with only deuterium and polystyrene capsules permeated with DT do exhibit thermal contraction. The highly cross-linked GDP shell is under compressive stress after fabrication and experiences bond breakage when exposed to high-density DT during permeation. It is speculated that some of this compressive stress is relieved during bond cleavage and the capsule’s wall swells, which counteracts contraction during cooling. In addition, mass spectrometry of the DT gas in the permeation system has revealed the presence of hydrocarbons and other carbon-containing species that increase with time, confirming the radio-degradation of the polymer.

Published
2018
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13. Requirements and Capabilities for Fielding Cryogenic DT-Containing Fill-Tube Targets for Direct-Drive Experiments on OMEGA

Author

Harding, D. R., Ulreich, J., Wittman, M. D., Chapman, R., Taylor, C., Taylor, R., Redden, N. P., Lambropoulos, J. C., Gram, R. Q., Bonino, M. J., and Turner, D. W.

Abstract

AbstractImproving the performance of direct-drive cryogenic targets at the Omega Laser Facility requires the development of a new cryogenic system to (1) field nonpermeable targets with a fill tube and (2) provide a clean environment around the target. This capability is to demonstrate that imploding a scaled-down version of the direct-drive ignition target for the National Ignition Facility (NIF) on the OMEGA laser will generate the hot-spot pressure that is needed for ignition; this will justify future cryogenic direct-drive experiments on the NIF cryogenic targets. The paper describes the target, the cryogenic equipment that is being constructed to achieve this goal, and the proposed target delivery process. Thermal calculations, fill tube–based target designs, and structural/vibrational analyses are provided to demonstrate the credibility of the design.This new design will include capabilities not available (or possible) with the existing OMEGA cryogenic system, with the emphasis being to preserve a pristinely clean environment around the target and to provide upgraded diagnostics to characterize both the ice layer and the target’s surface. The conceptual design is complete and testing of prototypes and subcomponents is underway. The rationale and capabilities of the new design are discussed.

Published
2018
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14. The National Direct-Drive Program: OMEGA to the National Ignition Facility

Author

Regan, S. P., Goncharov, V. N., Sangster, T. C., Campbell, E. M., Betti, R., Anderson, K. S., Bernat, T., Bose, A., Boehly, T. R., Bonino, M. J., Cao, D., Chapman, R., Collins, T. J. B., Craxton, R. S., Davis, A. K., Delettrez, J. A., Edgell, D. H., Epstein, R., Farrell, M., Forrest, C. J., Frenje, J. A., Froula, D. H., Johnson, M. Gatu, Gibson, C., Glebov, V. Yu., Greenwood, A., Harding, D. R., Hohenberger, M., Hu, S. X., Huang, H., Hund, J., Igumenshchev, I. V., Jacobs-Perkins, D. W., Janezic, R. T., Karasik, M., Keck, R. L., Kelly, J. H., Kessler, T. J., Knauer, J. P., Kosc, T. Z., Loucks, S. J., Marozas, J. A., Marshall, F. J., McCrory, R. L., McKenty, P. W., Meyerhofer, D. D., Michel, D. T., Myatt, J. F., Obenschain, S. P., Petrasso, R. D., Petta, N., Radha, P. B., Rosenberg, M. J., Schmitt, A. J., Schmitt, M. J., Schoff, M., Seka, W., Shmayda, W. T., Shoup, M. J., Shvydky, A., Solodov, A. A., Stoeckl, C., Sweet, W., Taylor, C., Taylor, R., Theobald, W., Ulreich, J., Wittman, M. D., Woo, K. M., and Zuegel, J. D.

Abstract

AbstractThe goal of the National Direct-Drive Program is to demonstrate and understand the physics of laser direct drive (LDD). Efforts are underway on OMEGA for the 100-Gbar Campaign to demonstrate and understand the physics for hot-spot conditions and formation relevant for ignition at the 1-MJ scale, and on the National Ignition Facility to develop an understanding of the direct-drive physics at long scale lengths for the MJ Direct-Drive Campaign. The strategy of the National Direct-Drive Program is described; the requirements for the deuterium-tritium cryogenic fill-tube target being developed for OMEGA are presented; and preliminary LDD implosion measurements of hydrodynamic mixing seeded by laser imprint, the target-mounting stalk, and microscopic surface debris are reported.

Published
2018
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19. INERTIAL CONFINEMENT FUSION RESEARCH AT THE LABORATORY OF LASER ENERGETICS

Author

McCrory, R. L., primary, Meyerhofer, D. D., additional, Loucks, S. J., additional, Skupsky, S., additional, Anderson, K. S., additional, Betti, R., additional, Boehly, T. R., additional, Bonino, M. J., additional, Craxton, R. S., additional, Collins, T. J. B., additional, Delettrez, J. A., additional, Edgell, D. H., additional, Epstein, R., additional, Glebov, V. Yu., additional, Goncharov, V. N., additional, Harding, D. R., additional, Keck, R. L., additional, Kelly, J. H., additional, Kessler, T. J., additional, Knauer, J. P., additional, Lund, L. D., additional, Jacobs-Perkins, D., additional, Marciante, J. R., additional, Marozas, J. A., additional, Marshall, F. J., additional, Maximov, A. V., additional, Maywar, D., additional, McKenty, P. W., additional, Morse, S. F. B., additional, Myatt, J., additional, Noyes, S. G., additional, Radha, P. B., additional, Sangster, T. C., additional, Seka, W., additional, Smalyuk, V. A., additional, Soures, J. M., additional, Stoeckl, C., additional, Theobald, W., additional, Thorp, K. A., additional, Wittman, M. D., additional, Yaakobi, B., additional, Zhou, C. D., additional, Zuegel, J. D., additional, Li, C. K., additional, Petrasso, R. D., additional, Frenje, J. A., additional, Séguin, F. H., additional, Panarella, Emilio, additional, and Raman, Roger, additional

Published
2009
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22. Producing Cryogenic Deuterium Targets for Experiments on OMEGA

Author

Harding, D. R., primary, Sangster, T. C., additional, Meyerhofer, D. D., additional, McKenty, P. W., additional, Lund, L. D., additional, Elasky, L., additional, Wittman, M. D., additional, Seka, W., additional, Loucks, S. J., additional, Janezic, R., additional, Hinterman, T. H., additional, Edgell, D. H., additional, Jacobs-Perkins, D., additional, and Gram, R. Q., additional

Published
2005
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23. Characterization of cryogenic direct-drive ICF targets during layering studies and just prior to shot time

Author

Edgell, D. H., Seka, W., Craxton, R. S., Elasky, L. M., Harding, D. R., Keck, R. L., Lund, L. D., Wittman, M. D., Edgell, D. H., Seka, W., Craxton, R. S., Elasky, L. M., Harding, D. R., Keck, R. L., Lund, L. D., and Wittman, M. D.

Abstract

The characterization of OMEGA cryogenic targets is based on shadowgraphs obtained from multiple angular views taken with the target in the layering sphere. The D2ice has been observed to re-layer during slow rotations, leading to procedural changes that avoid re-layering thus ensuring high-quality, spherical-harmonic, 3-D ice layer reconstructions. Shadowgrams taken inside the target chamber within 20 ms of shot time have verified that the ice layers remain preserved during the transport.

Published
2006
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27. Forming cryogenic targets for direct-drive experiments.

Author

Harding, D. R., Meyerhofer, D. D., Loucks, S. J., Lund, L. D., Janezic, R., Elasky, L. M., Hinterman, T. H., Edgell, D. H., Seka, W., Wittman, M. D., Gram, R. Q., Jacobs-Perkins, D., Early, R., Duffy, T., and Bonino, M. J.

Subjects
LOW temperature engineering, DEUTERIUM, FOURIER analysis, POLYCRYSTALS, SURFACE roughness, PHYSICS research
Abstract

More than 100 spherical deuterium ice layers have been formed to make cryogenic targets for direct-drive ICF implosion experiments on OMEGA. These ice layers have an inner surface roughness that ranges from 1.3 to 6μm root-mean-square (rms), with the best layers having a value less than 2 μm rms. These surface roughness values are averaged two-dimensional roughness measurements that cover the entire surface and includes all of the Fourier cosine modes. The ice thickness variation within the layer is predominately in the low spectral modes (mode 5 and lower) and is caused by the support used to hold the target. Changing the design of this support to minimize the thermal effect is constrained by the necessity of having a dynamically stable target for the implosion. We have demonstrated that it is possible to form crystalline ice layers that are facet-free and transparent by slowing the solidification rate of the liquid. Faster freezing rates form layers comprised of polycrystalline ice with a greater roughness (1 to 2 μm greater). Cooling an ice layer 0.5 K below the triple point temperature does not affect the roughness of the layer. Cooling the layer a further 1 K to achieve the desired internal gas pressure sometimes induces additional ice roughness; this roughness is manifest over low- to mid-spectral modes. Removing the thermal shrouds from around the target causes the ice to melt and the internal gas pressure to increase. Using the behavior of a cryogenic deuterium target as a reference, calculations of the response of the more interesting National Ignition Facility-scale deuterium and tritium targets show that exposing the target for 0.8 s to ambient radiation will cause ∼10% of the ice to melt and partially slump whereas the gas pressure will increase by 15%. [ABSTRACT FROM AUTHOR]

Published
2006
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31. Synthesis and Antitumor Activity of Novel C-7 Paclitaxel Ethers:  Discovery of BMS-184476

Author

Altstadt, T. J., Fairchild, C. R., Golik, J., Johnston, K. A., Kadow, J. F., Lee, F. Y., Long, B. H., Rose, W. C., Vyas, D. M., Wong, H., Wu, M.-J., and Wittman, M. D.

Abstract

The preparation of C-7 paclitaxel ethers is described. Various substituted ethers were prepared via activation of the corresponding methylthiomethyl ether followed by alcohol addition. Variation of the C-7 ether group as well the 3‘ side chain position led to the discovery of a novel taxane, BMS-184476 (4), with preclinical antitumor activity superior to paclitaxel.

Published
2001

44. Self-interference patterns and their application to inertial-fusion target characterization.

Author

Wittman MD and Craxton RS

Abstract

The sphericity and wall-thickness uniformity requirements of direct-drive inertial-fusion targets are of the order of less than 1%. These shells display self-interference patterns (SIP's) when irradiated with a spatially incoherent, narrow-bandwidth light source and viewed with a compound microscope. These patterns are distinct concentric fringes when the target is uniform, whereas faint, distorted, or discontinuous fringes indicate a nonuniform target. We determined the wall thickness to within +/-0.5 microm by counting the number of fringes in the SIP, independent of the outside diameter. Thickness uniformity is verified to an accuracy better than 0.05 microm. The wall thickness of gas-filled targets can be determined to this accuracy without knowledge of the type of gas or its pressure. The SIP fringe technique is used to select polymer shells typically of 800- to 1000-microm diameter and 5- to 12-microm wall thickness. The fringe locations have been modeled by use of ray tracing and agree well with actual measurements of well-characterized shells. Details of the formation of the SIP fringes, a theoretical model, and the method used for quantitative measurement of the shell-wall thickness with the SIP are presented with validation examples.

Published
1999
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