Organization: Physics (PH)
orgunit.page.dateEstablished
orgunit.page.dateDissolved
City
Country
Description
The mission of the Physics Department is to provide defense-relevant, advanced education and research programs to meet Naval unique needs, and increase the warfighting effectiveness of the U.S. Naval Forces, DoD and allied armed forces.
Type
Website of the organization
ID
Publication Search Results
Now showing 1 - 5 of 5
Publication Free Electron Laser material damage studies(Monterey, California. Naval Postgraduate School, 2000-11) McGinnis, Roger D.; Thomson, R. W.; Short, L. R.; Herbert, A.; Lampiris, D.; Christodoulou, A.; Colson, W. B.; Shinn, M. D.; Neil, G.; Benson, S.; Gubeli, J.; Evans, R.; Jordan, K.; Physics (PH); Thomas Jefferson National Accelerator Facility; Graduate School of Operational and Information Sciences (GSOIS); Naval Postgraduate School (U.S.); Institute for Joint Warfare AnalysisToday's surface ships are faced with an increased vulnerability to anti-ship cruise missiles, due to a change from operating in open oceans to primarily operating in the world's littorals. One possible solution to counter this threat is the use of a high-energy laser to destroy the missiles in flight. The Free Electron Laser is possibly the best choice of lasers for a marine environment since its wavelength can be changed over a wide range allowing the operator to choose the best wavelength to transmit through the atmosphere. Material damage studies on various anti-ship cruise missile materials were carried out at Thomas Jefferson National Accelerator Facility (TJNAF) in Newport News, Virginia. Experimental procedures presented in this report allow a scaled down laser of a few hundred to a few thousand watts to evaluate the damage from a weapon size laser of the megawatt class. The EEL beam bombards the target with a steady stream of picosecond length pulses at rates of 18MHz or greater. No other experiments have previously been done to explore the effects of the EEL pulse on materials. This report contains the work of several theses conducted at the Naval Postgraduate School over the past two years, and has been a productive cooperation among NPS, TJNAF, NRL, and NSWD at Port Hueneme, to the benefit of the Department of Defense.Publication UMD/NPS free electron laser research(Monterey, California. Naval Postgraduate School, 2008) Colson, William B.; Blau, Joseph; Physics (PH); Graduate School of Operational and Information Sciences (GSOIS); University of MarylandSimulations and theoretical analysis are used to study the development of high-average-power free electron lasers (FELs). Various existing and proposed FELs are studied, in both amplifier and oscillator configurations. Comparisons to experimental results show good agreement in each case. At the outset of this project, short Rayleigh length (SRL) optical cavities were proposed to reduce the optical intensity on the mirrors. Contrary to conventional wisdom, our simulations showed that an SRL FEL would have good gain and power extraction. This was recently confirmed experimentally at Jefferson Laboratory. System sensitivity to misalignments and distortions are also studied, and tolerance limits are established for tilts and shift of various components such as the mirrors, electron beam, and magnetic quadrupoles. These tolerances have already been readily achieved in laboratories using active alignment. The research done over 8 years on this project has resulted in 19 published papers, 21 M.S. theses, 2 Ph.D. dissertations, and 26 conference presentations, which are summarized in this report.Publication Jefferson lab free electron laser 10 kW upgrade - lessons learned(Monterey, California. Naval Postgraduate School, 2005) Williams, Brett; Physics (PH); Graduate School of Operational and Information Sciences (GSOIS); Naval Postgraduate School (U.S.)The activities of the Free Electron Laser (FEL) Group at Thomas Jefferson National Accelerator Facility (JLab) in Newport News, Virginia, during the Infrared Demonstration Free Electron Laser Upgrade Project are summarized. The project spanned four years, from July 2000 to June 2004, and resulted in the upgrade from a 1 kW-class FEL to a 10 kW-class FEL at JLab. Lessons learned during the Upgrade are presented and discussed.Publication Correction to attenuation treatment in the Monterey-Miami Parabolic Equation Model(Monterey, CA; Naval Postgraduate School, 2007) Smith, Kevin B.; Wolfson, Michael A.; van Leijen, A. Vincent; Physics (PH); Graduate School of Operational and Information Sciences (GSOIS); Naval Postgraduate School (U.S.)The purpose of this report is to notify those in the community who have used, or are using, the Monterey-Miami Parabolic Equation (MMPE) Model of an error in previous implementations that affects the computation of volume loss. The error has been corrected and an updated version is now available. Thorough analysis of the results are provided here, including comparison with exact modal attenuation factors for bottom loss parameters, which indicate the model is now performing properly.Publication Environmentally Adaptive Sonar Technology (EAST) project report for participation in the Littoral Warfare Advanced Development (LWAD) 99-3 experiment(Monterey, California. Naval Postgraduate School, 2000-08) Shipley, Mitchell N.; Physics (PH); Graduate School of Operational and Information Sciences (GSOIS); PhysicsThe objective of the Environmentally Adaptive Sonar Technology (EAST) project is to develop approaches to improve shallow water target detection for Navy active sonar systems. The current investigation involves using a time reversed acoustic pulse (TRAP) as a method of real time correction of propagation dispersion of the energy in an active sonar transmit waveform. The approach of the EAST project is predominantly experimentally based in the Naval Postgraduate Schools Advanced Acoustic Research Laboratory (AARL) shallow water tank facility. Computer modeling is also used to extend the experimental results to more realistic environments. The at sea experimental objectives of the EAST project in LWAD 99-3 were two fold: 1) Conduct a feasibility systems engineering test of a TRAP sonar system 2) At sea demonstration of about a 3dB improvement in SNR using a basic TRAP sonar approach over standard match filter active sonar signal processing for a single element sonar system.