ICALEPCS2013 - List of Authors (Awwal, A.A.S.)

Paper

Title

Page

Software Tool Leverages Existing Image Analysis Results to Provide In-Situ Transmission of the NIF Disposable Debris Shields

1270

V.J. Miller Kamm, A.A.S. Awwal, J.-M.G. Di Nicola, P. Di Nicola, S.N. Dixit, D.L. McGuigan, B.A. Raymond, K.C. Wilhelmsen
LLNL, Livermore, California, USA

Funding: * This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344. #LLNL-ABS-632472
The Disposable Debris-Shield (DDS) Attenuation Tool is software that leverages Automatic Alignment image analysis results and takes advantage of the DDS motorized insertion and removal to compute the in-situ transmission of the 192 NIF DDS. The NIF employs glass DDS to protect the final optics from debris and shrapnel generated by the laser-target interaction. Each DDS transmission must be closely monitored and replaced when its physical characteristics impact laser performance. The tool was developed to calculate the transmission by obtaining the total pixel intensity of acquired images with the debris shield inserted and removed. These total intensities existed in the Automatic Alignment image processing algorithms. The tool uses this data, adding the capability to specify DDS to test, moves the DDS, performs calculations, and saves data to an output file. It operates on all 192 beams of the NIF in parallel, and has shown a discrepancy between laser predictive models and actual. As qualification the transmission of new DDS were tested, with known transmissions supplied by the vendor. This demonstrated the tool capable of measuring in-situ DDS transmission to better than 0.5% rms.

Poster THPPC083 [2.362 MB]

THPPC085

Image Analysis for the Automated Alignment of the Advanced Radiography Capability (ARC) Diagnostic Path*

1274

R.S. Roberts, A.A.S. Awwal, E.S. Bliss, R.R. Leach, M.C. Rushford, K.C. Wilhelmsen
LLNL, Livermore, California, USA

Funding: *This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. #LLNL-ABS-631616
The Advanced Radiographic Capability (ARC) at the National Ignition Facility was developed to produce a sequence of short laser pulses that are used to backlight an imploding fuel capsule. This backlighting capability will enable the creation of a sequence of radiographs during capsule implosion and provide an unprecedented view into the dynamics of the implosion. A critical element of the ARC is the diagnostic instrumentation used to assess the quality of the pulses. Pulses are steered to the diagnostic package through a complex optical path that requires precision alignment. A central component of the alignment system is the image analysis algorithms, which are used to extract information from alignment imagery and provide feedback for the optical alignment control loops. Alignment imagery consists of complex patterns of light resulting from the diffraction of pilot beams around cross-hairs and other fiducials placed in the optical path. This paper describes the alignment imagery, and the image analysis algorithms used to extract the information needed for proper operation of the ARC automated alignment loops.

Poster THPPC085 [3.236 MB]

Paper	Title	Page
THPPC083	Software Tool Leverages Existing Image Analysis Results to Provide In-Situ Transmission of the NIF Disposable Debris Shields	1270
	V.J. Miller Kamm, A.A.S. Awwal, J.-M.G. Di Nicola, P. Di Nicola, S.N. Dixit, D.L. McGuigan, B.A. Raymond, K.C. Wilhelmsen LLNL, Livermore, California, USA
	Funding: * This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344. #LLNL-ABS-632472 The Disposable Debris-Shield (DDS) Attenuation Tool is software that leverages Automatic Alignment image analysis results and takes advantage of the DDS motorized insertion and removal to compute the in-situ transmission of the 192 NIF DDS. The NIF employs glass DDS to protect the final optics from debris and shrapnel generated by the laser-target interaction. Each DDS transmission must be closely monitored and replaced when its physical characteristics impact laser performance. The tool was developed to calculate the transmission by obtaining the total pixel intensity of acquired images with the debris shield inserted and removed. These total intensities existed in the Automatic Alignment image processing algorithms. The tool uses this data, adding the capability to specify DDS to test, moves the DDS, performs calculations, and saves data to an output file. It operates on all 192 beams of the NIF in parallel, and has shown a discrepancy between laser predictive models and actual. As qualification the transmission of new DDS were tested, with known transmissions supplied by the vendor. This demonstrated the tool capable of measuring in-situ DDS transmission to better than 0.5% rms.
	Poster THPPC083 [2.362 MB]

THPPC085	Image Analysis for the Automated Alignment of the Advanced Radiography Capability (ARC) Diagnostic Path*	1274
	R.S. Roberts, A.A.S. Awwal, E.S. Bliss, R.R. Leach, M.C. Rushford, K.C. Wilhelmsen LLNL, Livermore, California, USA
	Funding: *This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. #LLNL-ABS-631616 The Advanced Radiographic Capability (ARC) at the National Ignition Facility was developed to produce a sequence of short laser pulses that are used to backlight an imploding fuel capsule. This backlighting capability will enable the creation of a sequence of radiographs during capsule implosion and provide an unprecedented view into the dynamics of the implosion. A critical element of the ARC is the diagnostic instrumentation used to assess the quality of the pulses. Pulses are steered to the diagnostic package through a complex optical path that requires precision alignment. A central component of the alignment system is the image analysis algorithms, which are used to extract information from alignment imagery and provide feedback for the optical alignment control loops. Alignment imagery consists of complex patterns of light resulting from the diffraction of pilot beams around cross-hairs and other fiducials placed in the optical path. This paper describes the alignment imagery, and the image analysis algorithms used to extract the information needed for proper operation of the ARC automated alignment loops.
	Poster THPPC085 [3.236 MB]