2010 DPP Meeting
DPP 2010 Meeting Abstracts
Calibration of a Thomson parabola ion spectrometer using proton beams from a pelletron accelerator
Michael Canfield, Andrew Lombardo, Gavin Graeper, Collin Stillman, Charles Freeman; SUNY Geneseo Gennady Fiksel, Christian Stoeckl; Laboratory for Laser Energetics
Nareg Sinenian; Massachusetts Institute of Technology
The position-to-energy calibration of a Thomson parabola ion spectrometer (TPIS) was measured using proton beams from the 1.7 MV tandem pelletron accelerator at SUNY Geneseo. The TPIS was designed for use on the multiterawatt (MTW) laser facility at the Laboratory for Laser Energetics (LLE). The TPIS implements parallel electric and magnetic fields to separate ions of a given mass-to-charge ratio onto parabolic curves on the detector plane. The position of the ions along the parabola is used to determine the ions' energy. Monoenergetic proton beams with energies between approximately 1 and 3 MeV were directed into the TPIS. Both radiochromic film (RCF) and Fujifilm imaging plates (IP) were placed at the rear of the TPIS and were used to detect the protons. The horizontal deflection due to the electrostatic plates and the vertical deflection due to the permanent magnetic field were studied as a function of the proton energy.
*Funded in part by a grant from the DOE
Calibration of a Thomson parabola ion spectrometer and Fujifilm imaging plates for energetic protons, deuterons, and alpha particles
Charles Freeman, Michael Canfield, Gavin Graeper, Andrew Lombardo, Collin Stillman; SUNY Geneseo
Gennady Fiksel, Christian Stoeckl; Laboratory for Laser Energetics
Nareg Sinenian; Massachusetts Institute of Technology
A Thomson parabola ion spectrometer (TPIS) has been designed and built to study energetic ions accelerated from the rear surface of targets irradiated by ultra-intense laser light from the Multiterawatt (MTW) laser facility at the Laboratory for Laser Energetics (LLE). The device uses a permanent magnet and a pair of electrostatic deflector plates to produce parallel magnetic and electric fields, which cause ions of a given charge-to-mass ratio to be deflected onto parabolic curves on the detector plane. The position of the ion along the parabola can be used to determine its energy. Fujifilm imaging plates (IP) are placed in the rear of the device and are used to detect the incident ions. The energy dispersion of the spectrometer has been calibrated using monoenergetic ion beams from the SUNY Geneseo 1.7 MV pelletron accelerator. The IP sensitivity has been measured for protons and deuterons with energies between 0.6 MeV and 3.4 MeV, and for alpha particles with energies between 1.5 MeV and 5.1 MeV.
*Funded in part by a grant from the DOE
RaPToRS Sample Delivery System
Robert Henchen, Kye Shibata, Michael Krieger, Edward Pogozelski, Stephen Padalino; SUNY Geneseo
Gennady Fiksel, Christian Stoeckl; Laboratory for Laser Energetics
At various labs (NIF, LLE, NRL), activated material samples are used to measure reaction properties. The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system quickly and safely moves these radioactive samples through a closed PVC tube via airflow. The carrier travels from the reaction chamber to the control and analysis station, pneumatically braking at the outlet. A reversible multiplexer routes samples from various locations near the shot chamber to the analysis station. Also, the multiplexer allows users to remotely load unactivated samples without manually approaching the reaction chamber. All elements of the system (pneumatic drivers, flow control valves, optical position sensors, multiplexers, Geiger counters, and release gates at the analysis station) can be controlled manually or automatically using a custom LabVIEW interface. A prototype is currently operating at NRL in Washington DC. Prospective facilities for Raptors systems include LLE and NIF.
*Funded in part by a grant from the DOE
Multi-Detector Array for Measuring Tertiary Neutron Anisotropies in DT ICF Targets
Lee Gabler, Stephen Padalino, Danae Polsin, Megan Russ, Susan Thomas; SUNY Geneseo T. Craig Sangster; Laboratory for Laser Energetics
A nuclear diagnostic is being developed to ascertain if tertiary neutrons are distributed anisotropically during a DT ICF shot at the NIF. The system will use 8 ultra pure carbon disks as detectors. These disks will be strategically placed around the equatorial plane and polar regions of the NIF target chamber. Due to the high neutron activation threshold for carbon only tertiary neutrons will contribute to the 12C(n,2n)11C reaction. After the shot each disk will be placed between a matched pair of NaI detectors such that the 511 keV gamma rays produced by radioactive 11C can be measured in coincidence. The entire system will consist of eight pairs of detectors. A partial detector array with three NaI detector pairs encased in lead has been constructed at SUNY Geneseo. The optimal detector configuration, which reduced accidental coincidences, minimized background gamma counts and maximized geometric counting efficiency, was determined with this test bench in preparation for the construction of the full array.
*Funded in part by a grant from the DOE through the Laboratory for Laser Energetics
First Measurements of the absolute neutron spectrum using the Magnetic Recoil Spectrometer (MRS) at the NIF
J. Frenje, D. Casey, C. Li, F. Seguin, R. Petrasso; MIT R. Bionta, C. Cerjan, M. Eckart, S. Haan, S. Hatchett, H. Khater, O. Landen, A. Mackinnon, M. Moran, J. Rygg; LLNL
V. Glebov, T.C. Sangster, D. Meyerhofer, J. Magoon; LLE
K. Fletcher; SUNY Geneseo
J. Kilkenny; GA
R. Leeper; SNL
Proper assembly of capsule mass, as manifested through evolution of fuel areal density (?R), is fundamentally important for achieving hot-spot ignition planned at the National Ignition Facility (NIF). Experimental information about ?R and ?R asymmetries, Ti and yield is therefore essential for understanding how this assembly occurs. To obtain this information, a neutron spectrometer, called the Magnetic Recoil Spectrometer (MRS) has been implemented on the NIF. Its primary objective is to measure the absolute neutron spectrum in the range 5 to 30 MeV, from which ?R, Ti and yield can be directly inferred for both low-yield tritium-hydrogen-deuterium (THD) and high-yield DT implosions. In this talk, the results from the first measurements of the absolute neutron spectrum produced in exploding pusher and THD implosions will be presented.
*Work supported in part by the U.S. DOE, LLNL and LLE