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1

Possibilities for Nuclear Photo-Science with Intense Lasers  

SciTech Connect (OSTI)

The interaction of intense laser light with relativistic electrons can produce unique sources of high-energy x rays and gamma rays via Thomson scattering. ''Thomson-Radiated Extreme X-ray'' (T-REX) sources with peak photon brightness (photons per unit time per unit bandwidth per unit solid angle per unit area) that exceed that available from world's largest synchrotrons by more than 15 orders of magnitude are possible from optimally designed systems. Such sources offer the potential for development of ''nuclear photo-science'' applications in which the primary photon-atom interaction is with the nucleons and not the valence electrons. Applications include isotope-specific detection and imaging of materials, inverse density radiography, transmutation of nuclear waste and fundamental studies of nuclear structure. Because Thomson scattering cross sections are small, < 1 barn, the output from a T-REX source is optimized when the laser spot size and the electron spot size are minimized and when the electron and laser pulse durations are similar and short compared to the transit time through the focal region. The principle limitation to increased x-ray or gamma-ray brightness is ability to focus the electron beam. The effects of space charge on electron beam focus decrease approximately linearly with electron beam energy. For this reason, T-REX brightness increases rapidly as a function of the electron beam energy. As illustrated in Figure 1, above 100 keV these sources are unique in their ability to produce bright, narrow-beam, tunable, narrow-band gamma rays. New, intense, short-pulse, laser technologies for advanced T-REX sources are currently being developed at LLNL. The construction of a {approx}1 MeV-class machine with this technology is underway and will be used to excite nuclear resonance fluorescence in variety of materials. Nuclear resonance fluorescent spectra are unique signatures of each isotope and provide an ideal mechanism for identification of nuclear materials. With TREX it is possible to use NRF to provide high spatial resolution (micron scale) images of the isotopic distribution of all materials in a given object. Because of the high energy of the photons, imaging through dense and/or thick objects is possible. This technology will have applicability in many arenas including the survey of cargo for the presence of clandestine nuclear materials. It is also possible to address the more general radiographic challenge of imaging low-density objects that are shielded or placed behind high density objects. In this case, it is the NRF cross section and not the electron density of the material that provides contrast. Extensions of T-REX technology will be dependent upon the evolution of short pulse laser technology to high average powers. Concepts for sources that would produce 10's of kWs of gamma-rays by utilizing MW-class average-power, diode-pumped, short pulse lasers and energy recovery LINAC technology have been developed.

Barty, C J; Hartemann, F V; McNabb, D P; Messerly, M; Siders, C; Anderson, S; Barnes, P; Betts, S; Gibson, D; Hagmann, C; Hernandez, J; Johnson, M; Jovanovic, I; Norman, R; Pruet, J; Rosenswieg, J; Shverdin, M; Tremaine, A

2006-06-26T23:59:59.000Z

2

Astrophysics with Intense and Ultra-Intense Lasers "Laser Astrophysics"  

Science Journals Connector (OSTI)

......the experimental neutron yield and 1D simulation yield per input laser energy of 10 kJ are plotted as a function of the target...example, the evolution of stars. The energy generated by nuclear fusion around the center of the sun is transferred toward the outer......

Hideaki Takabe

2001-05-01T23:59:59.000Z

3

Laser intensity effects in noncommutative QED  

E-Print Network [OSTI]

We discuss a two-fold extension of QED assuming the presence of strong external fields provided by an ultra-intense laser and noncommutativity of spacetime. While noncommutative effects leave the electron's intensity induced mass shift unchanged, the photons change significantly in character: they acquire a quasi-momentum that is no longer light-like. We study the consequences of this combined noncommutative strong-field effect for basic lepton-photon interactions.

Thomas Heinzl; Anton Ilderton; Mattias Marklund

2010-02-17T23:59:59.000Z

4

Laser-Matter Interaction Above the Plasma Ignition Threshold Intensity  

Science Journals Connector (OSTI)

In this chapter we present the process of laser-matter interaction above the plasma ignition threshold intensity. The physics of the pulsed laser ablation process at high intensities is very complex since it invo...

Mihai Stafe; Aurelian Marcu; Niculae N. Puscas

2014-01-01T23:59:59.000Z

5

Laser-Matter Interaction Below the Plasma Ignition Threshold Intensity  

Science Journals Connector (OSTI)

In this chapter we present the process of laser-matter interaction below the plasma ignition threshold intensity. When the high power laser radiation characterized by electric field intensities around ...

Mihai Stafe; Aurelian Marcu; Niculae N. Puscas

2014-01-01T23:59:59.000Z

6

Electron acceleration by a self-diverging intense laser pulse K. P. Singh,1,  

E-Print Network [OSTI]

Electron acceleration by a self-diverging intense laser pulse K. P. Singh,1, * D. N. Gupta,1 V. K, India 2 Department of Electronic Science, University of Delhi, New Delhi-110021, India (Received 23 October 2003; published 28 April 2004) Electron acceleration by a laser pulse having a Gaussian radial

Singh, Kunwar Pal

7

High-power, high-intensity laser propagation and interactions  

SciTech Connect (OSTI)

This paper presents overviews of a number of processes and applications associated with high-power, high-intensity lasers, and their interactions. These processes and applications include: free electron lasers, backward Raman amplification, atmospheric propagation of laser pulses, laser driven acceleration, atmospheric lasing, and remote detection of radioactivity. The interrelated physical mechanisms in the various processes are discussed.

Sprangle, Phillip [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Electrical and Computer Engineering and Physics, University of Maryland, College Park, Maryland 20740 (United States); Hafizi, Bahman [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2014-05-15T23:59:59.000Z

8

Transverse spreading of electrons in high-intensity laser fields  

E-Print Network [OSTI]

We show that for collisions of electrons with a high-intensity laser, discrete photon emissions introduce a transverse beam spread which is distinct from that due to classical (or beam shape) effects. Via numerical simulations, we show that this quantum induced transverse momentum gain of the electron is manifest in collisions with a realistic laser pulse of intensity within reach of current technology, and we propose it as a measurable signature of strong-field quantum electrodynamics.

D. G. Green; C. N. Harvey

2014-03-18T23:59:59.000Z

9

Vacuum self-focussing of very intense laser beams  

E-Print Network [OSTI]

We argue that long-range photon-photon attraction induced by the dipole interaction of two electron-positron loops can lead to "vacuum self-focussing" of very intense laser beams. The focussing angle theta(F) is found to increase with the beam intensity I as theta(F) I^(4/3); for the laser beams available at present or in the near future, theta(F) 10^(-10)--10^(-7).

Dmitri Kharzeev; Kirill Tuchin

2007-02-21T23:59:59.000Z

10

Response of GaAs to fast intense laser pulses  

E-Print Network [OSTI]

Motivated by recent experiments, we have performed simulations which show in detail how the electrons and ions in GaAs respond to fast intense laser pulses (with durations of order 100 fs and intensities of order 1-10 TW/cm(2)). The method of tight...

Graves, JS; Allen, Roland E.

1998-01-01T23:59:59.000Z

11

Dynamics of intense laser propagation in underdense plasma: Polarization dependence  

SciTech Connect (OSTI)

We present a comprehensive numerical study of the dynamics of an intense laser pulse as it propagates through an underdense plasma in two and three dimensions. By varying the background plasma density and the polarization of the laser beam, significant differences are found in terms of energy transport and dissipation, in agreement with recently reported experimental results. Below the threshold for relativistic self-focusing, the plasma and laser dynamics are observed to be substantially insensitive to the initial laser polarization, since laser transport is dominated by ponderomotive effects. Above this threshold, relativistic effects become important, and laser energy is dissipated either by plasma heating (p-polarization) or by trapping of electromagnetic energy into plasma cavities (s-polarization) or by a combination of both (circular polarization). Besides the fundamental interest of this study, the results presented are relevant to applications such as plasma-based accelerators, x-ray lasers, and fast-ignition inertial confinement fusion.

Singh, D. K.; Fiuza, F.; Silva, L. O. [GoLP, Instituto de Plasmas e Fusao Nuclear - Laboratorio Associado, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal); Davies, J. R. [Fusion Science Center, Laboratory for Laser Energetics and Mechanical Engineering, University of Rochester, New York 14623 (United States); Sarri, G. [School of Mathematics and Physics, The Queens University of Belfast, Belfast BT7 1NN (United Kingdom)

2012-07-15T23:59:59.000Z

12

Sideband Mixing in Intense Laser Backgrounds  

E-Print Network [OSTI]

The electron propagator in a laser background has been shown to be made up of a series of sideband poles. In this paper we study this decomposition by analysing the impact of the residual gauge freedom in the Volkov solution on the sidebands. We show that the gauge transformations do not alter the location of the poles. The identification of the propagator from the two-point function is maintained but we show that the sideband structures mix under residual gauge transformations.

Martin Lavelle; David McMullan

2014-07-04T23:59:59.000Z

13

The Science DMZ: A Network Design Pattern for Data-Intensive Science  

E-Print Network [OSTI]

light source with a science dmz. http://www.globusworld.org/The Science DMZ: A Network DesignPattern for Data-Intensive Science Eli Dart Lauren Rotman

Rotman, Lauren

2014-01-01T23:59:59.000Z

14

Bragg cell laser intensity modulation: effect on laser Doppler velocimetry measurements  

SciTech Connect (OSTI)

In most laser Doppler velocimetry (LDV) systems, the frequency of one of the two laser beams that intersect to create the probe volume is shifted with an acousto-optic element. It is shown here that Bragg shifting can impose a problematic fluctuation in intensity on the frequency-shifted beam, producing spurious velocity measurements. This fluctuation occurs at twice the Bragg cell frequency, and its relative amplitude to the time average intensity is a function of the ratio of the laser beam diameter to the Bragg cell acoustic wavelength. A physical model and a configuration procedure to minimize adverse effects of the intensity modulations are presented.

Mychkovsky, Alexander G.; Chang, Natasha A.; Ceccio, Steven L.

2009-06-20T23:59:59.000Z

15

Investigation of laser-driven proton acceleration using ultra-short, ultra-intense laser pulses  

SciTech Connect (OSTI)

We report optimization of laser-driven proton acceleration, for a range of experimental parameters available from a single ultrafast Ti:sapphire laser system. We have characterized laser-generated protons produced at the rear and front target surfaces of thin solid targets (15 nm to 90 {mu}m thicknesses) irradiated with an ultra-intense laser pulse (up to 10{sup 20} W Dot-Operator cm{sup -2}, pulse duration 30 to 500 fs, and pulse energy 0.1 to 1.8 J). We find an almost symmetric behaviour for protons accelerated from rear and front sides, and a linear scaling of proton energy cut-off with increasing pulse energy. At constant laser intensity, we observe that the proton cut-off energy increases with increasing laser pulse duration, then roughly constant for pulses longer than 300 fs. Finally, we demonstrate that there is an optimum target thickness and pulse duration.

Fourmaux, S.; Gnedyuk, S.; Lassonde, P.; Payeur, S.; Pepin, H.; Kieffer, J. C. [INRS-EMT, Universite du Quebec, 1650 Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada); Buffechoux, S.; Albertazzi, B. [INRS-EMT, Universite du Quebec, 1650 Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada); LULI, UMR 7605, CNRS - CEA - Universite Paris 6 - Ecole Polytechnique, 91128 Palaiseau (France); Capelli, D.; Antici, P. [LULI, UMR 7605, CNRS - CEA - Universite Paris 6 - Ecole Polytechnique, 91128 Palaiseau (France); Dipartimento SBAI, Sapienza, Universita di Roma, Via Scarpa 16, 00161 Roma (Italy); Levy, A.; Fuchs, J. [LULI, UMR 7605, CNRS - CEA - Universite Paris 6 - Ecole Polytechnique, 91128 Palaiseau (France); Lecherbourg, L.; Marjoribanks, R. S. [Department of Physics and Institute for Optical Sciences, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)

2013-01-15T23:59:59.000Z

16

Calculations of population transfer during intense laser pulses  

SciTech Connect (OSTI)

Recent experiments by several groups have examined the question of population transfer to resonantly excited states during intense short laser pulses, in particular the amount of population that remains ``trapped`` in excited states at the end of a laser pulse. In this chapter we present calculations of population transfer and resonant ionization in xenon at both 660 and 620 nm. At the longer wavelength, the seven photon channel closes at 2.5{times}10{sup 13} W/cm{sup 2}. Pulses with peak intensities higher than this result in ``Rydberg trapping``, the resonant transfer of population to a broad range of high-lying states. The amount of population transferred depends on both the peak intensity and pulse duration. At 620 mm there are numerous possible six photon resonances to states with p or f angular momentum. We have done a large number of calculations for 40 fs pulses at different peak intensities and have examined the population transferred to these low-lying resonant states as a function of the peak laser intensity. We do not have room to comment upon the resonantly enhanced ionized electron energy spectra that we also determine in the same calculations. Our calculations involve the direct numerical integration of the time-dependent Schroedinger equation for an atom interacting with a strong laser field. The time-dependent wave function of a given valence electron is calculated on a spatial grid using a one-electron pseudo potential. This single active electron approximation (SAE) has been shown to be a good approximation for the rare gases at the intensities and wavelengths that we will consider. The SAE potential we use has an explicit angular momentum dependence which allows us to reproduce all of the excited state energies for xenon quite well.

Schafer, K.J.; Kulander, K.C.

1993-08-01T23:59:59.000Z

17

User Training for Data Intensive Science Co-Chairs: Fernanda...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

User Training for Data Intensive Science Co-Chairs: Fernanda Foertter, Tim Fahey 1 Contributors * Blaise Barney, LLNL * Karen Haskell, SNL * Bob Balance, SNL * Fernanda Foertter,...

18

Laser Induced Nuclear Fusion, LINF, In Muonic Molecules With Ultrashort Super Intense Laser Fields  

Science Journals Connector (OSTI)

Muonium molecules where muons replace electrons increase the stability of molecules to ionization at superhigh intensities I >10 20 ? W / cm 2 . We show furthermore from numerical simulations that in the nonsymmetric series pdu dtu ptu the permanent dipole moments can be used to enhance LINF Laser Induced Nuclear Fusion by laser induced recollision of the light nucleus with the heavier nucleus.

Andre D. Bandrauk; Gennady K. Paramonov

2010-01-01T23:59:59.000Z

19

Laser-Energy Transfer and Enhancement of Plasma Waves and Electron Beams by Interfering High-Intensity Laser Pulses  

E-Print Network [OSTI]

Laser-Energy Transfer and Enhancement of Plasma Waves and Electron Beams by Interfering High-Intensity) The effects of interference due to crossed laser beams were studied experimentally in the high- intensity regime. Two ultrashort (400 fs), high-intensity (4 1017 and 1:6 1018 W=cm2) and 1 m wavelength laser

Umstadter, Donald

20

Population trapping in Kr and Xe in intense laser fields  

Science Journals Connector (OSTI)

We have observed trapping of population in Rydberg states of atoms and ions exposed to intense laser radiation. The trapping occurs in nonstationary ‘‘wave-packet’’ superposition states, created, via ac Stark-shifted multiphoton resonances during the laser pulse. The formation of these highly excited bound states requires the nonresonant absorption of up to 20 or more photons; some of the ionic Rydberg states lie nearly 32 eV above the ionic ground state. All of the trapped states having binding energies much less than the photon energy but remain stable against ionization even when the multiphoton ionization probability of the atom is saturated.

R. R. Jones; D. W. Schumacher; P. H. Bucksbaum

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Molecular-bond hardening and dynamics of molecular stabilization and trapping in intense laser pulses  

E-Print Network [OSTI]

stabilization and population trapping of high-lying vibrational states and chemical bond hardening are predicted for both continuous-wave (cw) lasers and short laser pulses. While the intensity dependences of the laser-induced stabilization are essentially...

Yao, Guanhua; Chu, Shih-I

1993-07-01T23:59:59.000Z

22

DOE Science Showcase - Free-Electron Lasers | OSTI, US Dept of Energy,  

Office of Scientific and Technical Information (OSTI)

Free-Electron Lasers Free-Electron Lasers Free-Electron Lasers absorb and release energy at any wavelength and can be controlled more precisely than conventional lasers by producing intense powerful light in brief bursts with extreme precision. This innovative technology has opened doors to a vast array of possibilities for manufacturing and for basic research. Read more in the white paper In OSTI Collections: Free-Electron Lasers by Dr. William Watson, Physicist, OSTI staff. Free-Electron Lasers Results in DOE Databases Science.gov Ciencia.Science.gov (Español) WorldWideScience.org Energy Citations Database DOE Information Bridge Relevant Subject Clusters FREE ELECTRON LASERS PARTICLE ACCELERATORS ENGINEERING LASERS ELECTRON BEAMS ACCELERATORS WIGGLER MAGNETS EQUIPMENT ELECTROMAGNETIC RADIATION

23

Laser Induced Nuclear Fusion, LINF, In Muonic Molecules With Ultrashort Super Intense Laser Fields  

SciTech Connect (OSTI)

Muonium molecules where muons replace electrons increase the stability of molecules to ionization at superhigh intensities, I>10{sup 20} W/cm{sup 2}. We show furthermore from numerical simulations that in the nonsymmetric series, pdu, dtu, ptu, the permanent dipole moments can be used to enhance LINF, Laser Induced Nuclear Fusion by laser induced recollision of the light nucleus with the heavier nucleus.

Bandrauk, Andre D. [Faculte des sciences, Universite de Sherbrooke, Quebec, J1K 2R1 (Canada); Paramonov, Gennady K. [Institut fur Chemie, FU Berlin-14195 Berlin (Germany)

2010-02-02T23:59:59.000Z

24

Ultlra-intense laser-matter interactions at extreme parameters  

SciTech Connect (OSTI)

The field of shortpulse lasers has seen rapid growth in the recent years with the three major boundaries of energy, pulse duration and repetition rate being pushed in ever extremer regions. At peak powers, already exceeding 10{sup 22} W/cm{sup 2}, in virtually every experiment in relativistic laser physics, the laser pulse interacts with a more or less extended and heated plasma, due to prepulses and ASE-like pedestals on ps - ns time scales. By developing a new technique for ultrahigh contrast, we were able to initiate the next paradigm shift in relativistic laser-matter interactions, allowing us to interact ultrarelativistic pulses volumetrically with overdense targets. This becomes possible by using target and laser parameters that will turn the target relativistically transparent during the few 10s-100s femtoseconds fo the interaction. Specifically, we interact an ultraintese, ultrahigh contrast pulse with solid density, free standing, nanometer diamond target. This paradigm change towards a volumetric overdense interaction in turn enables new particle acceleration mechanisms for both electrons and ions, as well as forward directed relativistic surface harmonics. We report here on first experiments done on those topics at the 200 TW Trident laser at Los Alamos as well as at the Ti:Sapphire system at MBI. We will compare the experimental data to massive large scale 3D simulations done on the prototype of LANL's new Petafiop supercomputer Roadrunner, which is leading the current top 500 list. Specifically, we developed a shortpulse OPA based pulse cleaning technique. Fielding it at the Trident 200 TW laser at Los Alamos, we were able to improve the pulse contrast by 6 orders of magnitude to better than 2 x 10{sup -12} at less than a ps. This enabled for the first time the interaction of a 100J, 200TW laser pulse with a truly solid target with virtually no expansion before the main pulse - target interaction, making possible the use of very thin targets, The thinnest of these at less than 3nm, i.e. 1/300 of the laser wavelength, are even thinner than the plasma skin depth. This drastically changes the laser-matter interaction physics leading to the emergence of new particle acceleration mechanisms, like Break-Out Afterburner (BOA) Acceleration, driven by a relativistic, kinetic plasma instability or Radiation Pressure Acceleration (RPA), driven by stabilized charge separation. Furthermore, these interactions also produce relativistic high harmonics in forward direction as well as mono-en,ergetic electron pulses which might lend itself as a source for fully coherent Thomson scattering in the mulit-keV regime. In this talk I will present an overview over the laser developments leading to this paradigm change as well as over the theoretical and experimental results following from it. Specifically we were able for the first time to demonstrate BOA acceleration of Carbon ions to up to 0.5 GeV using a laser pulse with {approx}10{sup 20} W/cm{sup 2} intensity and showing the scalability of this mechanism into regimes relevant for Hadron Therapy. We were further able to demonstrate mono-energetic electron break-out from ultrathin targets, as a first step towards a flying mirror.

Hegellich, Bjorn M [Los Alamos National Laboratory

2010-11-24T23:59:59.000Z

25

Third harmonic order imaging as a focal spot diagnostic for high intensity laser-solid interactions  

E-Print Network [OSTI]

intensity inter- actions, i.e., fast ignition fusion, laser based ion acceleration etc., where fluctuationsThird harmonic order imaging as a focal spot diagnostic for high intensity laser-solid interactions, Glasgow, UK 4 Central Laser Facility, STFC Rutherford Appleton Laboratory. Chilton, Didcot, Didcot, UK 5

Strathclyde, University of

26

Injection of harmonics generated in gas in a free-electron laser providing intense and  

E-Print Network [OSTI]

-ultraviolet to X-ray region. Recently, injection of a single-pass FEL by the third laser harmonic of a TiLETTERS Injection of harmonics generated in gas in a free-electron laser providing intense-electron lasers promise to extend this down to femtosecond timescales. The process by which free-electron lasers

Loss, Daniel

27

Ultrahigh-intensity optical slow-wave structure for direct laser electron acceleration  

E-Print Network [OSTI]

WAVEGUIDE Ultraintense laser­plasma interaction applications in- cluding x-ray lasers, coherentUltrahigh-intensity optical slow-wave structure for direct laser electron acceleration Andrew G of corrugated slow-wave plasma guiding structures with application to quasi- phase-matched direct laser

Milchberg, Howard

28

Molecules in intense laser fields: Beyond the dipole approximation  

SciTech Connect (OSTI)

The time-dependent Schroedinger equation is solved for a Born-Oppenheimer (static nuclei) three-dimensional H{sub 2}{sup +} in super intense laser fields (I=4x10{sup 18}, 10{sup 19}, and 4x10{sup 19} W/cm{sup 2}) at wavelength {lambda}{sub L}=45 nm and 25 nm to assess the influence of nondipolar (magnetic) effects on high order harmonic generation spectra in molecules. It is found that even harmonics appear due to the magnetic field component direction perpendicular to the electric field polarization with intensities about two orders of magnitude less than the odd harmonics emitted along the electric field polarization. The even harmonics exhibit plateaus with cutoffs which exceed in intensity the odd harmonic plateaus and maximum energies predicted by semiclassical electron recollision models. Although the spectra are weak, the wavelength of the recollision electron in the maximum energy regions correspond to subatomic dimensions and the corresponding emitted photons have subnanometer wavelengths.

Bandrauk, A. D.; Lu, H. Z. [Laboratoire de Chimie Theorique, Universite de Sherbrooke, Sherbrooke, Que, J1K 2R1 (Canada)

2006-01-15T23:59:59.000Z

29

High-frequency intensity noise of lead-salt diode lasers  

Science Journals Connector (OSTI)

The high-frequency intensity noise spectra of mid-infrared diode lasers have been investigated. Theoretical estimates are compared with experimental results of spectral noise...

Fischer, H; Tacke, M

1991-01-01T23:59:59.000Z

30

Generation of mega-electron-volt electron beams by an ultrafast intense laser pulse  

E-Print Network [OSTI]

Generation of mega-electron-volt electron beams by an ultrafast intense laser pulse Xiaofang Wang filamentation and beam breakup. These results suggest an approach for generating a beam of femtosecond, Me-intensity lasers has made it pos- sible to study extreme physics on a tabletop. Among the studies, the generation

Umstadter, Donald

31

Experimental measurements of multiphoton enhanced air breakdown by a subthreshold intensity excimer laser  

E-Print Network [OSTI]

laser Jesse Way,a Jason Hummelt, and John Scharer Department of Electrical and Computer Engineering measurements of laser induced breakdown plasma in atmospheric air by subthreshold intensity 5.5 109 W/cm2 193 nm laser radiation. Using molecular spectroscopy and two-wavelength interferometry, it is shown

Scharer, John E.

32

Dopant induced ignition of helium nanodroplets in intense few-cycle laser pulses  

E-Print Network [OSTI]

We demonstrate ultrafast resonant energy absorption of rare-gas doped He nanodroplets from intense few-cycle (~10 fs) laser pulses. We find that less than 10 dopant atoms "ignite" the droplet to generate a non-spherical electronic nanoplasma resulting ultimately in complete ionization and disintegration of all atoms, although the pristine He droplet is transparent for the laser intensities applied. Our calculations at those intensities reveal that the minimal pulse length required for ignition is about 9 fs.

Krishnan, S R; Kremer, M; Sharma, V; Fischer, B; Camus, N; Jha, J; Krishnamurthy, M; Pfeifer, T; Moshammer, R; Ullrich, J; Stienkemeier, F; Mudrich, M; Mikaberidze, A; Saalmann, U; Rost, J -M

2011-01-01T23:59:59.000Z

33

Present and future perspectives for high energy density physics with intense heavy ion and laser beams  

E-Print Network [OSTI]

Present and future perspectives for high energy density physics with intense heavy ion and laser18, deliver an intense uranium beam that deposit about 1 kJ0g specific energy in solid matter. Using 2004! Abstract Intense heavy ion beams from the Gesellschaft fĂĽr Schwerionenforschung ~GSI, Darmstadt

34

Apparatus and process for active pulse intensity control of laser beam  

DOE Patents [OSTI]

An optically controlled laser pulse energy control apparatus and process is disclosed wherein variations in the energy of a portion of the laser beam are used to vary the resistance of a photodetector such as a photoresistor through which a control voltage is fed to a light intensity controlling device through which a second portion of the laser beam passes. Light attenuation means are provided to vary the intensity of the laser light used to control the resistance of the photodetector. An optical delay path is provided through which the second portion of the beam travels before reaching the light intensity controlling device. The control voltage is supplied by a variable power supply. The apparatus may be tuned to properly attenuate the laser beam passing through the intensity controlling device by adjusting the power supply, the optical delay path, or the light attenuating means.

Wilcox, Russell B. (Oakland, CA)

1992-01-01T23:59:59.000Z

35

X-ray spectroscopy of buried layer foils irradiated with an ultra high intensity short pulse laser  

E-Print Network [OSTI]

the intensity of the ignition laser pulse is be at least 10fuel [19, 22]. Current ignition laser requirements mandatesShort pulse laser produced plasmas Fast Ignition guides much

Chen, Sophia Nan

2009-01-01T23:59:59.000Z

36

Hollow screw like drill in plasma using an intense Laguerre Gaussian laser  

E-Print Network [OSTI]

With the development of ultra intense laser technology, MeV ions from the laser foil interaction have been obtained by different mechanisms, such as target normal sheath acceleration, radiation pressure acceleration, collisionless shock acceleration, breakout afterburner, and a combination of different mechanisms. These energetic ion beams can be applied in fast ignition for inertial confinement fusion, medical therapy, and proton imaging. However, these ions are mainly accelerated in the laser propagation direction, and the ion acceleration in an azimuthal orientation is scarcely mentioned. Here, a doughnut Laguerre Gaussian LG laser is used for the first time to study the laser plasma interaction in the relativistic intensity regime in three dimensional particle in cell simulations. Studies have shown that a novel rotation of the plasma is produced from the hollow screw like drill of a LG mode laser. The angular momentum of the protons in the longitudinal direction produced by the LG laser is remarkably enh...

Wang, Wenpeng; Zhang, Xiaomei; Zhang, Lingang; Shi, Yin; Xu, Zhizhan

2014-01-01T23:59:59.000Z

37

ANALYSIS AND MITIGATION OF X-RAY HAZARD GENERATED FROM HIGH INTENSITY LASER-TARGET INTERACTIONS  

SciTech Connect (OSTI)

Interaction of a high intensity laser with matter may generate an ionizing radiation hazard. Very limited studies have been made, however, on the laser-induced radiation protection issue. This work reviews available literature on the physics and characteristics of laser-induced X-ray hazards. Important aspects include the laser-to-electron energy conversion efficiency, electron angular distribution, electron energy spectrum and effective temperature, and bremsstrahlung production of X-rays in the target. The possible X-ray dose rates for several femtosecond Ti:sapphire laser systems used at SLAC, including the short pulse laser system for the Matter in Extreme Conditions Instrument (peak power 4 TW and peak intensity 2.4 x 10{sup 18} W/cm{sup 2}) were analysed. A graded approach to mitigate the laser-induced X-ray hazard with a combination of engineered and administrative controls is also proposed.

Qiu, R.; Liu, J.C.; Prinz, A.A.; Rokni, S.H.; Woods, M.; Xia, Z.; /SLAC; ,

2011-03-21T23:59:59.000Z

38

Narrowband inverse Compton scattering x-ray sources at high laser intensities  

E-Print Network [OSTI]

Narrowband x- and gamma-ray sources based on the inverse Compton scattering of laser pulses suffer from a limitation of the allowed laser intensity due to the onset of nonlinear effects that increase their bandwidth. It has been suggested that laser pulses with a suitable frequency modulation could compensate this ponderomotive broadening and reduce the bandwidth of the spectral lines, which would allow to operate narrowband Compton sources in the high-intensity regime. In this paper we, therefore, present the theory of nonlinear Compton scattering in a frequency modulated intense laser pulse. We systematically derive the optimal frequency modulation of the laser pulse from the scattering matrix element of nonlinear Compton scattering, taking into account the electron spin and recoil. We show that, for some particular scattering angle, an optimized frequency modulation completely cancels the ponderomotive broadening for all harmonics of the backscattered light. We also explore how sensitive this compensation ...

Seipt, D; Surzhykov, A; Fritzsche, S

2014-01-01T23:59:59.000Z

39

Lasers, Photonics, and Fusion Science: Bringing Star Power to...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

to our News Alerts * Your Email Address: * Preferred Format: HTML Text Subscribe Latest NIF & Photon Science News Simulating the Birth of Giant Planets Laser-driven compression...

40

Nonlinear dynamics of ionization stabilization of atoms in intense laser fields  

E-Print Network [OSTI]

We revisit the stabilization of ionization of atoms subjected to a superintense laser pulse using nonlinear dynamics. We provide an explanation for the lack of complete ionization at high intensity and for the decrease of the ionization probability as intensity is increased. We investigate the role of each part of the laser pulse (ramp-up, plateau, ramp-down) in this process. We emphasize the role of the choice for the ionization criterion, energy versus distance criterion.

Michael Norman; C. Chandre; T. Uzer; Peijie Wang

2014-12-06T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Limitations on the Attainable Intensity of High Power Lasers  

SciTech Connect (OSTI)

It is shown that even a single e{sup -}e{sup +} pair created by a superstrong laser field in vacuum would cause development of an avalanchelike QED cascade which rapidly depletes the incoming laser pulse. This confirms Bohr's old conjecture that the electric field of the critical QED strength E{sub S}=m{sup 2}c{sup 3}/e({h_bar}/2{pi}) could never be created.

Fedotov, A. M.; Narozhny, N. B.; Mourou, G.; Korn, G. [National Research Nuclear University MEPhI, Moscow 115409 (Russian Federation); Institut de la Lumiere Extreme, UMS 3205 ENSTA, Ecole Polytechnique, CNRS, 91761 Palaiseau (France); Max Plank Institute for Quantum Optics, Garching 85748 (Germany)

2010-08-20T23:59:59.000Z

42

Diffraction Gratings for High-Intensity Laser Applications  

SciTech Connect (OSTI)

The scattering of light into wavelength-dependent discrete directions (orders) by a device exhibiting a periodic modulation of a physical attribute on a spatial scale similar to the wavelength of light has been the subject of study for over 200 years. Such a device is called a diffraction grating. Practical applications of diffraction gratings, mainly for spectroscopy, have been around for over 100 years. The importance of diffraction gratings in spectroscopy for the measurement of myriad properties of matter can hardly be overestimated. Since the advent of coherent light sources (lasers) in the 1960's, applications of diffraction gratings in spectroscopy have further exploded. Lasers have opened a vast application space for gratings, and apace, gratings have enabled entirely new classes of laser systems. Excellent reviews of the history, fundamental properties, applications and manufacturing techniques of diffraction gratings up to the time of their publication can be found in the books by Hutley (1) and more recently Loewen and Popov (2). The limited scope of this chapter can hardly do justice to such a comprehensive subject, so the focus here will be narrowly limited to characteristics required for gratings suitable for high-power laser applications, and methods to fabricate them. A particular area of emphasis will be on maximally-efficient large-aperture gratings for short-pulse laser generation.

Britten, J

2008-01-23T23:59:59.000Z

43

Ultra hard x rays from krypton clusters heated by intense laser fields R. C. Issac,a)  

E-Print Network [OSTI]

drives a fast ignition wave.15 Prop- erties of the cluster media as well as the incident laser paUltra hard x rays from krypton clusters heated by intense laser fields R. C. Issac,a) G. Vieux, B of ultrashort laser pulses with krypton clusters at intensity up to 1.3 1018 Wcm 2 has been investigated

Strathclyde, University of

44

High–intensity lasers: interactions with atoms, molecules and clusters  

Science Journals Connector (OSTI)

...tra from around 2500-atom xenon clusters irradiated by 2 1016...charge states up to 12+ in xenon and 8+ in krypton at an intensity...process converts the coherent oscillation energy of the electron cloud...result of a resonantly driven oscillation of the entire cluster elec...

1998-01-01T23:59:59.000Z

45

Advances in Laser Science-II  

SciTech Connect (OSTI)

The meeting covered topics on the latest advances in laser technology and applications. The general categories are as follows: advanced lasers and coherent sources; nonlinear optical phenomena and applications; atomic, molecular and ionic spectroscopy; condensed matter, surface and particle spectroscopy; laser photochemistry and photophysics; diagnostic and analytical applications of lasers; and laser research and techniques in medicine and biology. (LSP)

Lapp, M.; Stwalley, W.C.; Kenney-Wallace, G.A.; Lerner, R.G. (eds.)

1987-01-01T23:59:59.000Z

46

Intensity-resolved Above Threshold Ionization Yields of Atoms with Ultrashort Laser Pulses  

E-Print Network [OSTI]

. Electron ionization yields of xenon were measured for a set of laser pulse intensities using a time of flight (TOF) setup. Horizontally polarized, unchirped, pulses were used in the ionization process. All laser parameters other than the radiation... Tiezer, I am grateful for all their time and help. I would like to thank Dr. James Strohaber for detailed discussions and assistance related to this experiment. I acknowledge the Department of Physics at Texas A&M and the US Air Force...

Hart, Nathan Andrew

2012-10-19T23:59:59.000Z

47

Dynamical Schwinger effect and high-intensity lasers. Realising nonperturbative QED  

E-Print Network [OSTI]

We consider the possibility of experimental verification of vacuum e^+e^- pair creation at the focus of two counter-propagating optical laser beams with intensities 10^{20}-10^{22} W/cm^2, achievable with present-day petawatt lasers, and approaching the Schwinger limit: 10^{29} W/cm^2 to be reached at ELI. Our approach is based on the collisionless kinetic equation for the evolution of the e^+ and e^- distribution functions governed by a non-Markovian source term for pair production. As possible experimental signals of vacuum pair production we consider e^+e^- annihilation into gamma-pairs and the refraction of a high-frequency probe laser beam by the produced e^+e^- plasma. We discuss the dependence of the dynamical pair production process on laser wavelength, with special emphasis on applications in the X-ray domain (X-FEL), as well as the prospects for \\mu^+\\mu^- and \\pi^+\\pi^- pair creation at high-intensity lasers. We investigate perspectives for using high-intensity lasers as ``boosters'' of ion beams in the few-GeV per nucleon range, which is relevant, e.g., to the exploration of the QCD phase transition in laboratory experiments.

D. B. Blaschke; A. V. Prozorkevich; G. Roepke; C. D. Roberts; S. M. Schmidt; D. S. Shkirmanov; S. A. Smolyansky

2008-11-21T23:59:59.000Z

48

Saturation of Photoluminescence from Carbon Nanotubes at High Laser Intensities: Exciton-Exciton Annihilation near the Mott Density  

E-Print Network [OSTI]

Saturation of Photoluminescence from Carbon Nanotubes at High Laser Intensities: Exciton) spectroscopy of individualized carbon nanotube ensembles has been carried out using wavelength completely flat, where the PL intensity became independent of the excitation wavelength (Fig. 1). Through

Maruyama, Shigeo

49

Stationary self-focusing of intense laser beam in cold quantum plasma using ramp density profile  

SciTech Connect (OSTI)

By using a transient density profile, we have demonstrated stationary self-focusing of an electromagnetic Gaussian beam in cold quantum plasma. The paper is devoted to the prospects of using upward increasing ramp density profile of an inhomogeneous nonlinear medium with quantum effects in self-focusing mechanism of high intense laser beam. We have found that the upward ramp density profile in addition to quantum effects causes much higher oscillation and better focusing of laser beam in cold quantum plasma in comparison to that in the classical relativistic case. Our computational results reveal the importance and influence of formation of electron density profiles in enhancing laser self-focusing.

Habibi, M. [Department of Physics, Shirvan Branch, Islamic Azad University, Shirvan (Iran, Islamic Republic of); Ghamari, F. [Department of Physics, Khorramabad Branch, Islamic Azad University, Khorramabad (Iran, Islamic Republic of)

2012-10-15T23:59:59.000Z

50

Chemical and Laser Sciences Division annual report 1989  

SciTech Connect (OSTI)

The Chemical and Laser Sciences Division Annual Report includes articles describing representative research and development activities within the Division, as well as major programs to which the Division makes significant contributions.

Haines, N. (ed.)

1990-06-01T23:59:59.000Z

51

Experimental Observation of Electrons Accelerated in Vacuum to Relativistic Energies by a High-Intensity Laser  

Science Journals Connector (OSTI)

Free electrons have been accelerated in vacuum to MeV energies by a high-intensity subpicosecond laser pulse ( 1019 W/cm2, 300 fs). The experimental data are in good agreement with the relativistic motion of electrons in a spatially and temporally finite electromagnetic field, both in terms of maximum energy and scattering angle.

G. Malka; E. Lefebvre; J. L. Miquel

1997-04-28T23:59:59.000Z

52

Systems for controlling the intensity variations in a laser beam and for frequency conversion thereof  

DOE Patents [OSTI]

In order to control the intensity of a laser beam so that its intensity varies uniformly and provides uniform illumination of a target, such as a laser fusion target, a broad bandwidth laser pulse is spectrally dispersed spatially so that the frequency components thereof are spread apart. A disperser (grating) provides an output beam which varies spatially in wavelength in at least one direction transverse to the direction of propagation of the beam. Temporal spread (time delay) across the beam is corrected by using a phase delay device (a time delay compensation echelon). The dispersed beam may be amplified with laser amplifiers and frequency converted (doubled, tripled or quadrupled in frequency) with nonlinear optical elements (birefringent crystals). The spectral variation across the beam is compensated by varying the angle of incidence on one of the crystals with respect to the crystal optical axis utilizing a lens which diverges the beam. Another lens after the frequency converter may be used to recollimate the beam. The frequency converted beam is recombined so that portions of different frequency interfere and, unlike interference between waves of the same wavelength, there results an intensity pattern with rapid temoral oscillations which average out rapidly in time thereby producing uniform illumination on target. A distributed phase plate (also known as a random phase mask), through which the spectrally dispersed beam is passed and then focused on a target, is used to provide the interference pattern which becomes nearly modulation free and uniform in intensity in the direction of the spectral variation.

Skupsky, Stanley (Rochester, NY); Craxton, R. Stephen (Rochester, NY); Soures, John (Pittsford, NY)

1990-01-01T23:59:59.000Z

53

Ignition of Doped Helium Nanodroplets in Intense Few-Cycle Laser Pulses  

Science Journals Connector (OSTI)

The ultra-fast dynamics of He nanodroplets (103–105 atoms) in intense (1…7 ×1014 W/cm2...), few-cycle (?10 fs), infrared (?790 nm) laser pulses has been investigated as a function ... number of dopant rare-gas at...

S. R. Krishnan; L. Fechner; M. Kremer…

2012-01-01T23:59:59.000Z

54

Radiative lifetime of barbell excitons in semiparabolic double quantum wells under intense laser fields  

Science Journals Connector (OSTI)

Abstract The binding energy and optical properties of barbell excitons in GaAs–Ga1?xAlxAs semiparabolic double quantum wells under intense laser fields are investigated. Calculations are performed within the effective mass and envelope-function approximations, including the conduction band nonparabolicity. The dependence of the binding energy, oscillator strength and exciton absorption spectrum on the laser field in symmetric and asymmetric quantum wells is studied by using a finite difference method. It is shown that the exciton radiative lifetime can be tuned to a large extent by a proper choice of the structure design (double well size, middle barrier position and its thickness) as well as by varying the laser field intensity.

E.C. Niculescu

2013-01-01T23:59:59.000Z

55

Ionization behavior of molecular hydrogen in intense laser fields: Influence of molecular vibration and alignment  

E-Print Network [OSTI]

The alignment- and internuclear-distance dependent ionization of H$_2$ exposed to intense, ultrashort laser fields is studied by solving the time-dependent two-electron Schr\\"odinger equation. In the regime of perturbative few-photon ionization, a strong dependence of the ionization yield on the internuclear distance is found. While this finding confirms a previously reported breakdown of the fixed-nuclei approximation for parallel alignment, a simpler explanation is provided and it is demonstrated that this breakdown is not due to vibrational dynamics during the laser pulse. The persistence of this effect even for randomly aligned molecules is demonstrated. Furthermore, the transition from the multiphoton to the quasi-static (tunneling) regime is investigated considering intense 800 nm laser pulses. While the obtained ionization yields differ significantly from the prediction of Ammosov-Delone-Krainov rates, we find a surprisingly good quantitative agreement after introducing a simple frequency-dependent cor...

Förster, Johann; Saenz, Alejandro

2014-01-01T23:59:59.000Z

56

Suppression of intensity noise of a laser-diode-pumped single-frequency Nd:YVO4 laser by optoelectronic control  

E-Print Network [OSTI]

by optoelectronic control Jing Zhang, Hongliang Ma, Changde Xie, and Kunchi Peng The intensity-noise reduction of a laser-diode-pumped single-frequency ring Nd:YVO4 laser when differ- ent optoelectronic control systems techniques, optoelectronic feedback control of the drive current of the pump laser diode and feed

Zhang, Jing

57

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double pulses  

E-Print Network [OSTI]

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double laser-produced plasmas are bright ultrafast line x-ray sources potentially suitable for different onto a solid target into the x-ray emission is significantly enhanced when a laser prepulse precedes

Limpouch, Jiri

58

Line X-ray emission from Al targets irradiated by high-intensity, variable-length laser pulses  

E-Print Network [OSTI]

Line X-ray emission from Al targets irradiated by high-intensity, variable-length laser pulses J; the scaling rules for the conversion efficiency of the laser radiation into the line X-ray emission are discussed. Keywords: Laser-produced plasma; Line X-ray emission; X-ray sources; X-ray spectroscopy 1

Limpouch, Jiri

59

X-Ray Radiation from Nonlinear Thomson Scattering of an Intense Femtosecond Laser on Relativistic Electrons in a Helium Plasma  

E-Print Network [OSTI]

X-Ray Radiation from Nonlinear Thomson Scattering of an Intense Femtosecond Laser on Relativistic laser beam on plasma electrons. A collimated x-ray radiation with a broad continuous spectrum peaked by the ultraintense laser fields. The results show the existence of several physical mecha- nisms for the x-ray

Umstadter, Donald

60

Observations of the filamentation of high-intensity laser-produced electron beams M. S. Wei,1  

E-Print Network [OSTI]

be necessary for actual ignition experiments, the required laser needs to have energies of tens of kObservations of the filamentation of high-intensity laser-produced electron beams M. S. Wei,1 F. N Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Oxon OX11 OQX, United Kingdom 5

Strathclyde, University of

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Lasers without Mirrors, Designed by Supercomputer - NERSC SCience News  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Lasers without Lasers without Mirrors, Designed by Supercomputer Lasers without Mirrors, Designed by Supercomputer October 14, 2009 | Tags: Lasers, Life Sciences, Materials Science Contact: Ji Qiang | Lawrence Berkeley National Laboratory | JQiang@lbl.gov John Corlett | Lawrence Berkeley National Laboratory, Center for Beam Physics | JNCorlett@lbl.gov Sometimes it takes a big machine to understand the tiniest details. That's the case with free electron lasers (FELs). The powerful X-rays they generate can probe matter directly at the level of atomic interactions and chemical-bond formation, letting scientists observe such phenomena as chemical reactions in trace elements, electric charges in photosynthesis and the structure of microscopic machines. FELs have the potential to

62

Experimental measurements of multiphoton enhanced air breakdown by a subthreshold intensity excimer laser  

SciTech Connect (OSTI)

This work presents density, spectroscopic temperature, and shockwave measurements of laser induced breakdown plasma in atmospheric air by subthreshold intensity (5.5x10{sup 9} W/cm{sup 2}) 193 nm laser radiation. Using molecular spectroscopy and two-wavelength interferometry, it is shown that substantial ionization (>10{sup 16} cm{sup -3}) occurs that is not predicted by collisional cascade (CC) breakdown theory. While the focused laser irradiance is three orders of magnitude below the theoretical collisional breakdown threshold, the substantial photon energy at 193 nm (6.42 eV/photon) compared with the ionization potential of air (15.6 eV) significantly increases the probability of multiphoton ionization effects. By spectroscopically monitoring the intensity of the N{sub 2}{sup +} first negative system (B {sup 2}SIGMA{sub u}{sup +}-X {sup 2}SIGMA{sub g}{sup +}) vibrational bandhead (v{sup '}=0,v{sup ''}=0) at low pressure (20 Torr) where multiphoton effects are dominant, it is shown that two photon excitation, resonant enhanced multiphoton ionization is the primary mechanism for quantized ionization of N{sub 2} to the N{sub 2}{sup +}(B {sup 2}SIGMA{sub u}{sup +}) state. This multiphoton effect then serves to amplify the collisional breakdown process at higher pressures by electron seeding, thereby reducing the threshold intensity from that required via CC processes for breakdown and producing high density laser formed plasmas.

Way, Jesse; Hummelt, Jason; Scharer, John [Department of Electrical and Computer Engineering, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2009-10-15T23:59:59.000Z

63

A STAGED MUON-BASED FACILITY TO ENABLE INTENSITY AND ENERGY FRONTIER SCIENCE IN THE US*  

E-Print Network [OSTI]

A STAGED MUON-BASED FACILITY TO ENABLE INTENSITY AND ENERGY FRONTIER SCIENCE IN THE US* Jean. It requires facilities at both high energy and high intensity frontiers. Neutrino oscillations are irrefutable precision flavour physics at the high intensity frontier. At the high energy frontier, a multi-TeV lepton

McDonald, Kirk

64

Observations of the filamentation of high-intensity laser-produced electron beams  

SciTech Connect (OSTI)

Filamented electron beams have been observed to be emitted from the rear of thin solid targets irradiated by a high-intensity short-pulse laser when there is low-density plasma present at the back of the target. These observations are consistent with a laser-generated beam of relativistic electrons propagating through the target, which is subsequently fragmented by a Weibel-like instability in the low-density plasma at the rear. These measurements are in agreement with particle-in-cell simulations and theory, since the filamentation instability is predicted to be dramatically enhanced when the electron beam density approaches that of the background plasma.

Wei, M.S.; Beg, F.N.; Dangor, A.E.; Gopal, A.; Tatarakis, M.; Krushelnick, K. [Blackett Laboratory, Imperial College London SW7 2BZ (United Kingdom); Clark, E.L.; Evans, R.G. [Blackett Laboratory, Imperial College London SW7 2BZ (United Kingdom); Plasma Physics Department, AWE plc, Aldermaston, Reading RG7 4PR (United Kingdom); Ledingham, K.W.D. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Plasma Physics Department, AWE plc, Aldermaston, Reading RG7 4PR (United Kingdom); McKenna, P. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Norreys, P.A. [Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Oxon OX11 OQX (United Kingdom); Zepf, M. [Department of Physics, The Queen's University, University Road, Belfast BT7 1NN (United Kingdom)

2004-11-01T23:59:59.000Z

65

Replica Symmetry Breaking in the Intensity Fluctuation Overlap of Random Laser Emission Spectra  

E-Print Network [OSTI]

We report about a newly introduced overlap parameter of intensity fluctuations of waves in random media with arbitrary amount of disorder and non-linearity and its relationship to the replica theory overlap in the $2+4$ spherical complex spin-glass model. Symmetry breaking in the intensity fluctuation overlap is shown to be equivalent to the one occurring in the complex amplitude overlap, providing an easily verifiable test in typical experimental setups. The relevance of this order parameter is considered in describing the laser transition in random media and in explaining its glassy nature in terms of emission spectra data. The theoretical analysis is compared to recent measurements.

Antenucci, Fabrizio; Leuzzi, Luca

2015-01-01T23:59:59.000Z

66

Nonsequential double ionization below laser-intensity threshold: Anticorrelation of electrons without excitation of parent ion  

SciTech Connect (OSTI)

Two-electron correlated spectra of nonsequential double ionization below laser-intensity threshold are known to exhibit back-to-back scattering of the electrons, i.e., the anticorrelation of the electrons. Currently, the widely accepted interpretation of the anticorrelation is recollision-induced excitation of the ion plus subsequent field ionization of the second electron. We argue that another mechanism, namely, simultaneous electron emission, when the time of return of the rescattered electron is equal to the time of liberation of the bounded electron (i.e., the ion has no time for excitation), can also explain the anticorrelation of the electrons in the deep, below laser-intensity threshold regime. Our conclusion is based on the results of the numerical solution of the time-dependent Schroedinger equation for a model system of two one-dimensional electrons, as well as on an adiabatic analytic model that allows for a closed-form solution.

Bondar, D. I. [University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Yudin, G. L. [National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Universite de Sherbrooke, Sherbrooke, Quebec J1K 2R1 (Canada); Liu, W.-K. [University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Ivanov, M. Yu. [Imperial College, London SW7 2BW (United Kingdom); Bandrauk, A. D. [Universite de Sherbrooke, Sherbrooke, Quebec J1K 2R1 (Canada)

2011-01-15T23:59:59.000Z

67

Electric dipole-forbidden nuclear transitions driven by super-intense laser fields  

E-Print Network [OSTI]

Electric dipole-forbidden transitions of nuclei interacting with super-intense laser fields are investigated considering stable isotopes with suitable low-lying first excited states. Different classes of transitions are identified, and all magnetic sublevels corresponding to the near-resonantly driven nuclear transition are included in the description of the nuclear quantum system. We find that large transition matrix elements and convenient resonance energies qualify nuclear M1 transitions as good candidates for the coherent driving of nuclei. We discuss the implications of resonant interaction of intense laser fields with nuclei beyond the dipole approximation for the controlled preparation of excited nuclear states and important aspects of possible experiments aimed at observing these effects.

Adriana Pálffy; Jörg Evers; Christoph H. Keitel

2008-04-14T23:59:59.000Z

68

Electric-dipole-forbidden nuclear transitions driven by super-intense laser fields  

Science Journals Connector (OSTI)

Electric-dipole-forbidden transitions of nuclei interacting with super-intense laser fields are investigated by considering stable isotopes with suitable low-lying first excited states. Different classes of transitions are identified, and all magnetic sublevels corresponding to the near-resonantly driven nuclear transition are included in the description of the nuclear quantum system. We find that large transition matrix elements and convenient resonance energies qualify nuclear M1 transitions as good candidates for the coherent driving of nuclei. We discuss the implications of resonant interaction of intense laser fields with nuclei beyond the dipole approximation for the controlled preparation of excited nuclear states and important aspects of possible experiments aimed at observing these effects.

Adriana Pálffy, Jörg Evers, and Christoph H. Keitel

2008-04-11T23:59:59.000Z

69

Hole boring in a DT pellet and fast ion ignition with ultra-intense laser pulses  

E-Print Network [OSTI]

Recently achieved high intensities of short laser pulses open new prospects in their application to hole boring in inhomogeneous overdense plasmas and for ignition in precompressed DT fusion targets. A simple analytical model and numerical simulations demonstrate that pulses with intensities exceeding 1022 W/cm2 may penetrate deeply into the plasma as a result of efficient ponderomotive acceleration of ions in the forward direction. The penetration depth as big as hundreds of microns depends on the laser fluence, which has to exceed a few tens of GJ/cm2. The fast ions, accelerated at the bottom of the channel with an efficiency of more than 20%, show a high directionality and may heat the precompressed target core to fusion conditions.

Naumova, N; Tikhonchuk, V T; Labaune, C; Sokolov, I V; Mourou, G; 10.1103/PhysRevLett.102.025002

2009-01-01T23:59:59.000Z

70

Standoff detection of hidden objects using backscattered ultra-intense laser-produced x-rays  

SciTech Connect (OSTI)

Ultra-intense laser-produced sub-ps X-ray pulses can detect backscattered signals from objects hidden in aluminium containers. Coincident measurements using primary X-rays enable differentiation among acrylic, copper, and lead blocks inside the container. Backscattering reveals the shapes of the objects, while their material composition can be identified from the modification methods of the energy spectra of backscattered X-ray beams. This achievement is an important step toward more effective homeland security.

Kuwabara, H. [IHI Corporation, 1, Shin-Nakahara-cho, Isogo-ku, Yokohama 235-8501 (Japan)] [IHI Corporation, 1, Shin-Nakahara-cho, Isogo-ku, Yokohama 235-8501 (Japan); Mori, Y.; Kitagawa, Y. [The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsucho, Nishiku, Hamamatsu, Shizuoka 431-1202 (Japan)] [The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsucho, Nishiku, Hamamatsu, Shizuoka 431-1202 (Japan)

2013-08-28T23:59:59.000Z

71

Epithermal Neutron Source for Neutron Resonance Spectroscopy (NRS) using High Intensity, Short Pulse Lasers  

SciTech Connect (OSTI)

A neutron source for neutron resonance spectroscopy (NRS) has been developed using high intensity, short pulse lasers. This measurement technique will allow for robust measurements of interior ion temperature of laser-shocked materials and provide insight into equation of state (EOS) measurements. The neutron generation technique uses protons accelerated by lasers off of Cu foils to create neutrons in LiF, through (p,n) reactions with {sup 7}Li and {sup 19}F. The distribution of the incident proton beam has been diagnosed using radiochromic film (RCF). This distribution is used as the input for a (p,n) neturon prediction code which is compared to experimentally measured neutron yields. From this calculation, a total fluence of 1.8 x 10{sup 9} neutrons is infered, which is shown to be a reasonable amount for NRS temperature measurement.

Higginson, D P; McNaney, J M; Swift, D C; Bartal, T; Hey, D S; Pape, S L; Mackinnon, A; Mariscal, D; Nakamura, H; Nakanii, N; Beg, F N

2010-04-22T23:59:59.000Z

72

Self-focusing, channel formation, and high-energy ion generation in interaction of an intense short laser pulse with a He jet  

E-Print Network [OSTI]

Self-focusing, channel formation, and high-energy ion generation in interaction of an intense short of interaction of a relativistically intense 4-TW, 400-fs laser pulse with a He gas jet. We observe a stable data, we reconstructed the axial profile of laser channel and on-axis laser intensity. The estimated

Umstadter, Donald

73

Intensity Frontier: More Information | U.S. DOE Office of Science (SC)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Intensity Intensity Frontier » Intensity Frontier: More Information High Energy Physics (HEP) HEP Home About Research Snowmass / P5 Planning Process Intensity Frontier Cosmic Frontier Theoretical Physics Advanced Technology R&D Accelerator R&D Stewardship Research Highlights .pdf file (13.1MB) Questions for the Universe Accomplishments Facilities Science Highlights Benefits of HEP Funding Opportunities Advisory Committees News & Resources Contact Information High Energy Physics U.S. Department of Energy SC-25/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3624 F: (301) 903-2597 E: sc.hep@science.doe.gov More Information » Intensity Frontier Intensity Frontier: More Information Print Text Size: A A A RSS Feeds FeedbackShare Page Experiments at the Intensity Frontier aim to transform our understanding of

74

Fermilab | Science at Fermilab | Experiments & Projects | Intensity  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Intensity Frontier Intensity Frontier Experiments at the Intensity Frontier ArgoNeuT MINERvA MiniBooNE MINOS NOvA LBNE Cosmic Frontier Proposed Projects and Experiments ArgoNeuT ArgoNeut detector at Proton Assembly Building Intensity Frontier ArgoNeuT The Argon Neutrino Teststand or ArgoNeuT detector, nicknamed for Jason and the Argonauts of Greek mythology, is a liquid argon neutrino detector at Fermilab. Argon is a noble, non-toxic element that in its gaseous form constitutes about 1 percent of air. It exists as a colorless liquid only in the narrow temperature range of minus 186 to minus 189 degrees Celsius. Neutrinos passing through a large volume of argon can interact with an argon atom, producing secondary particles such as muons and protons, which then ionize other argon atoms. An electric field within the detector causes

75

Fast neutron emission from a deuterated polystyrene solid target irradiated by a high-intensity laser pulse  

Science Journals Connector (OSTI)

Fast neutrons were generated from a deuterated polystyrene (C8D8) solid-target irradiated by a high-intensity laser. A TOF neutron signal is analyzed in detail. A...

Lee, Sungman; Kwon, Sungok; Lee, Kitae; Cha, Yong-Ho; Yea, Kwon-hae; Lee, Yong Woo; Lee, Ji Young; Jeong, Young Uk; Rhee, Yong Joo; Cha, Hyungki

76

Fast neutron emission from a deuterated polystyrene solid target irradiated by a high-intensity laser pulse  

Science Journals Connector (OSTI)

Fast neutrons were generated from a deuterated polystyrene (C8D8) solid-target irradiated by a high-intensity laser. A TOF neutron signal is analyzed in detail....

Lee, Sungman; Kwon, Sungok; Lee, Kitae; Cha, Yong-Ho; Yea, Kwon-hae; Lee, Yong Woo; Lee, Ji Young; Jeong, Young Uk; Rhee, Yong Joo; Cha, Hyungki

77

Production of neutrons up to 18 MeV in high-intensity, short-pulse laser matter interactions  

E-Print Network [OSTI]

was 0.5%, an order of magnitude greater than into deuterons. Maximum neutron energy was shown-intensity, petawatt class lasers may provide an attractive alternate with rela- tively lower costs,

78

Data Grids: a new computational infrastructure for data-intensive science  

Science Journals Connector (OSTI)

...Goodfellow, Dominic Tildesley and Maggie Wilson Data Grids: a new computational infrastructure for data-intensive science Paul Avery Department of...geographic dispersion and their reliance on large data archives. These characteristics bring with...

2002-01-01T23:59:59.000Z

79

Nonresonant femtosecond laser vaporization of aqueous protein preserves folded structure  

Science Journals Connector (OSTI)

...molecules and ions in strong laser fields . Phys Rev A 68 : 011402...generated by ultra-intense lasers . Science 300 : 1107 – 1111 . 10 Ditmire T ( 1999 ) Nuclear fusion from explosions of femtosecond laser-heated deuterium clusters . Nature...

John J. Brady; Elizabeth J. Judge; Robert J. Levis

2011-01-01T23:59:59.000Z

80

Experiments at the Intensity Frontier | U.S. DOE Office of Science (SC)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Intensity Frontier Intensity Frontier High Energy Physics (HEP) HEP Home About Research Facilities Facility Ops Experiments at the Energy Frontier Experiments at the Intensity Frontier Experiments at the Cosmic Frontier Projects, Missions, and Status HEP User Facilities Science Highlights Benefits of HEP Funding Opportunities Advisory Committees News & Resources Contact Information High Energy Physics U.S. Department of Energy SC-25/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3624 F: (301) 903-2597 E: sc.hep@science.doe.gov More Information » Facilities Experiments at the Intensity Frontier Print Text Size: A A A RSS Feeds FeedbackShare Page The Intensity Frontier, accessed with a combination of intense particle beams and highly sensitive detectors, offers a second, unique investigation

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

A search for the sulphur hexafluoride cation with intense, few cycle laser pulses  

SciTech Connect (OSTI)

It is well established that upon ionization of sulphur hexafluoride, the SF{sub 6}{sup +} ion is never observed in mass spectra. Recent work with ultrashort intense laser pulses has offered indications that when strong optical field are used, the resulting “bond hardening” can induce changes in the potential energy surfaces of molecular cations such that molecular ions that are normally unstable may, indeed, become metastable enough to enable their detection by mass spectrometry. Do intense, ultrashort laser pulses permit formation of SF{sub 6}{sup +}? We have utilized intense pulses of 5 fs, 11 fs, and 22 fs to explore this possibility. Our results are negative: no evidence is discovered for SF{sub 6}{sup +}. However, multiply charged sulphur and fluorine ions from highly charged SF{sub 6}{sup q+} ions are observed that enable us to resolve the controversy regarding the kinetic energy release accompanying formation of F{sup +} fragment ions. Quantum chemical computations of field-distorted potential energy curves of SF{sub 6} and its molecular ion enable us to rationalize our non-observation of SF{sub 6}{sup +}. Our findings have implications for high harmonic generation from SF{sub 6} in the few-cycle regime.

Dota, Krithika; Mathur, Deepak, E-mail: atmol1@tifr.res.in [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India) [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India); Centre for Atomic and Molecular Physics, Manipal University, Manipal 576 104 (India); Dharmadhikari, Aditya K. [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)] [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India); Dharmadhikari, Jayashree A. [Centre for Atomic and Molecular Physics, Manipal University, Manipal 576 104 (India)] [Centre for Atomic and Molecular Physics, Manipal University, Manipal 576 104 (India); Patra, Kaustuv; Tiwari, Ashwani K. [Indian Institute of Science Education and Research - Kolkata, Mohanpur 741 252 (India)] [Indian Institute of Science Education and Research - Kolkata, Mohanpur 741 252 (India)

2013-11-21T23:59:59.000Z

82

Ion heating dynamics in solid buried layer targets irradiated by ultra-short intense laser pulses  

SciTech Connect (OSTI)

We investigate bulk ion heating in solid buried layer targets irradiated by ultra-short laser pulses of relativistic intensities using particle-in-cell simulations. Our study focuses on a CD{sub 2}-Al-CD{sub 2} sandwich target geometry. We find enhanced deuteron ion heating in a layer compressed by the expanding aluminium layer. A pressure gradient created at the Al-CD{sub 2} interface pushes this layer of deuteron ions towards the outer regions of the target. During its passage through the target, deuteron ions are constantly injected into this layer. Our simulations suggest that the directed collective outward motion of the layer is converted into thermal motion inside the layer, leading to deuteron temperatures higher than those found in the rest of the target. This enhanced heating can already be observed at laser pulse durations as low as 100 fs. Thus, detailed experimental surveys at repetition rates of several ten laser shots per minute are in reach at current high-power laser systems, which would allow for probing and optimizing the heating dynamics.

Huang, L. G. [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, 201800 Shanghai (China) [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, 201800 Shanghai (China); Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany) [Germany; University of Chinese Academy of Sciences, 100049 Beijing (China); Bussmann, M.; Kluge, T. [Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany)] [Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany); Lei, A. L. [Shanghai Institute of Laser Plasma, 201800 Shanghai (China)] [Shanghai Institute of Laser Plasma, 201800 Shanghai (China); Yu, W. [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, 201800 Shanghai (China)] [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, 201800 Shanghai (China); Cowan, T. E. [Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany) [Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany); Technische Universität Dresden, 01062 Dresden (Germany)

2013-09-15T23:59:59.000Z

83

Collisionless absorption, hot electron generation, and energy scaling in intense laser-target interaction  

E-Print Network [OSTI]

Among the various attempts to understand collisionless absorption of intense ultrashort laser pulses a variety of models has been invented to describe the laser beam target interaction. In terms of basic physics collisionless absorption is understood now as the interplay of the oscillating laser field with the space charge field produced in the plasma. A first approach to this idea is realized in Brunel's model the essence of which consists in the formation of an oscillating charge cloud in the vacuum in front of the target. The investigation of statistical ensembles of orbits shows that the absorption process is localized at the ion-vacuum interface and in the skin layer: Single electrons enter into resonance with the laser field thereby undergoing a phase shift which causes orbit crossing and braking of Brunel's laminar flow. This anharmonic resonance acts like an attractor for the electrons and leads to the formation of a Maxwellian tail in the electron energy spectrum. Most remarkable results of our inves...

Liseykina, T; Murakami, M

2014-01-01T23:59:59.000Z

84

Enhanced Nonlinear Double Excitation of He in Intense Extreme Ultraviolet Laser Fields  

SciTech Connect (OSTI)

Nonlinear, three-photon double excitation of He in intense extreme ultraviolet free-electron laser fields ({approx}24.1 eV, {approx}5 TW/cm{sup 2}) is presented. Resonances to the doubly excited states converging to the He{sup +} N=3 level are revealed by the shot-by-shot photoelectron spectroscopy and identified by theoretical calculations based on the time-dependent Schroedinger equation for the two-electron atom under a laser field. It is shown that the three-photon double excitation is enhanced by intermediate Rydberg states below the first ionization threshold, giving a greater contribution to the photoionization yields than the two-photon process by more than 1 order of magnitude.

Hishikawa, A.; Matsuda, A. [Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602 (Japan); Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585 (Japan); RIKEN/SPring-8, Sayo, Hyogo 679-5148 (Japan); Fushitani, M. [Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602 (Japan); RIKEN/SPring-8, Sayo, Hyogo 679-5148 (Japan); Hikosaka, Y. [RIKEN/SPring-8, Sayo, Hyogo 679-5148 (Japan); Department of Environmental Science, Niigata University, Niigata, Niigata 950-2181 (Japan); Liu, C.-N. [Department of Physics, Fu-Jen Catholic University, Taipei 24205, Taiwan (China); Morishita, T. [Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585 (Japan); PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Shigemasa, E. [Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585 (Japan); RIKEN/SPring-8, Sayo, Hyogo 679-5148 (Japan); Nagasono, M.; Ishikawa, T. [RIKEN/SPring-8, Sayo, Hyogo 679-5148 (Japan); Tono, K.; Togashi, T.; Senba, Y. [JASRI/SPring-8, Sayo, Hyogo 679-5198 (Japan); Ohashi, H.; Kimura, H.; Yabashi, M. [RIKEN/SPring-8, Sayo, Hyogo 679-5148 (Japan); JASRI/SPring-8, Sayo, Hyogo 679-5198 (Japan)

2011-12-09T23:59:59.000Z

85

Momentum distributions of sequential ionization generated by an intense laser pulse  

E-Print Network [OSTI]

beam is produced in an EBIT (electron beam ion trap) that is kept at a potential of approximately 5 kV, and which can produce xenon ions with charges ranging from Xe1+ to around Xe20+. Selecting the desired initial charge state with a Wienfilter... that is on the order of its rest energy. Taking into account that the oscillation energy of a free electron is F 2/4?2, one can easily find that relativistic effects occur for radiation of the Ti:Sa laser at the intensity greater than 5? 1018 W/cm2 (see Ref. [2...

Shvetsov-Shilovski, N. I.; Sayler, A. M.; Rathje, T.; Paulus, Gerhard G.

2011-01-01T23:59:59.000Z

86

A focusable, convergent fast-electron beam from ultra-high-intensity laser-solid interactions  

E-Print Network [OSTI]

A novel scheme for the creation of a convergent, or focussing, fast-electron beam generated from ultra-high-intensity laser-solid interactions is described. Self-consistent particle-in-cell simulations are used to demonstrate the efficacy of this scheme in two dimensions. It is shown that a beam of fast-electrons of energy 500 keV - 3 MeV propagates within a solid-density plasma, focussing at depth. The depth of focus of the fast-electron beam is controlled via the target dimensions and focussing optics.

Scott, R H H

2015-01-01T23:59:59.000Z

87

Fermilab | Science at Fermilab | Experiments & Projects | Intensity  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Intensity Frontier Intensity Frontier MiniBooNE Researchers initiated the Booster Neutrino Experiment, BooNE, to verify definitively the results of the Los Alamos Liquid Scintillator Neutrino Detector experiment. In 1995, the Los Alamos experiment presented strong evidence for the oscillation of muon anti-neutrinos into electron anti-neutrinos. Jasmine Ma inspects one of the phototubes that detects light from neutrino interactions. (Courtesy: Peter Ginter) Jasmine Ma inspects one of the phototubes that detects light from neutrino interactions. (Courtesy: Peter Ginter) The 800-ton detector, called MiniBooNE, searches for neutrino oscillations. The detector is located 500 meters from Fermilab's second neutrino source, the Booster Neutrino Beam or BNB. The presence of neutrinos can only be inferred by detecting the charged

88

Intensity clamping measurement of laser filaments in air at 400 and 800 nm  

SciTech Connect (OSTI)

Molecular N{sub 2} fluorescence excited by laser filaments formed from laser pulses at 400 and 800 nm propagating in air is investigated. A comparison showed that, when excited with 400 nm photons, the fluorescence from the first negative band of N{sub 2}{sup +} was enhanced by a factor of 6.4 while that of the second positive band of neutral N{sub 2} remained relatively constant. The enhanced N{sub 2}{sup +} signal is attributed to a more efficient inner-shell multiphoton process (to the B{sup 2{Sigma}}{sub u}{sup +} state) at 400 nm leaving a larger population of N{sub 2}{sup +} ions in the excited state. On the other hand, the stable fluorescence from neutral N{sub 2} is due to the fact that the plasma density is more or less the same at both wavelengths. Using these results, a theoretical model is developed to determine the clamped intensities of the laser filaments at 400 and 800 nm.

Daigle, J.-F.; Hosseini, S.; Wang, T.-J.; Kamali, Y.; Chin, S. L. [Centre d'Optique, Photonique et Laser (COPL) and Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, Quebec G1V 0A6 (Canada); Jaron-Becker, A.; Becker, A. [JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440 (United States); Roy, G. [Defence Research and Development Canada-Valcartier, 2459 Pie-XI Boulevard North, Quebec, Quebec G3J 1X5 (Canada)

2010-08-15T23:59:59.000Z

89

Dissociation of H{sub 2}{sup +} in intense femtosecond laser fields studied by coincidence three-dimensional momentum imaging  

SciTech Connect (OSTI)

The dissociation of H{sub 2}{sup +} in an intense laser field has been experimentally studied using femtosecond laser pulses at 790 nm in the intensity range of 10{sup 13}-10{sup 15} W/cm{sup 2}. Kinematically complete measurements of both the ionic H{sup +} and neutral H fragments dissociated from a vibrationally excited H{sub 2}{sup +} beam have been achieved by a coincidence three-dimensional momentum imaging system. Angular-resolved kinetic energy release spectra for a series of different intensity ranges have been obtained using the intensity-difference spectrum method, thus disentangling the problem caused by the intensity volume effect. Our results indicate that the dissociation dynamics are drastically different for 'long' (135 fs) and 'short' (45 fs) laser pulses at similar high laser intensities. Specifically, bond softening is found to be the main feature in long pulses, while above threshold dissociation is dominant in short pulses whose durations are comparable with the vibrational period of the molecule. Bond softening in short pulses appears at low kinetic energy release with a narrow angular distribution. The experimental results are well interpreted by solving the time-dependent Schroedinger equation in the Born-Oppenheimer representation without nuclear rotation.

Wang, P. Q.; Sayler, A. M.; Carnes, K. D.; Xia, J. F.; Smith, M. A.; Esry, B. D.; Ben-Itzhak, I. [J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States)

2006-10-15T23:59:59.000Z

90

Laser Ranging for Gravitational, Lunar, and Planetary Science  

E-Print Network [OSTI]

More precise lunar and Martian ranging will enable unprecedented tests of Einstein's theory of General Relativity and well as lunar and planetary science. NASA is currently planning several missions to return to the Moon, and it is natural to consider if precision laser ranging instruments should be included. New advanced retroreflector arrays at carefully chosen landing sites would have an immediate positive impact on lunar and gravitational studies. Laser transponders are currently being developed that may offer an advantage over passive ranging, and could be adapted for use on Mars and other distant objects. Precision ranging capability can also be combined with optical communications for an extremely versatile instrument. In this paper we discuss the science that can be gained by improved lunar and Martian ranging along with several technologies that can be used for this purpose.

Stephen M. Merkowitz; Philip W. Dabney; Jeffrey C. Livas; Jan F. McGarry; Gregory A. Neumann; Thomas W. Zagwodzki

2007-12-20T23:59:59.000Z

91

Relativistic nonlinear dynamics of an intense laser beam propagating in a hot electron-positron magnetoactive plasma  

SciTech Connect (OSTI)

The present study is devoted to investigation of the nonlinear dynamics of an intense laser beam interacting with a hot magnetized electron-positron plasma. Propagation of the intense circularly polarized laser beam along an external magnetic field is studied using a relativistic two-fluid model. A modified nonlinear Schrödinger equation is derived based on the quasi-neutral approximation, which is valid for hot plasma. Light envelope solitary waves and modulation instability are studied, for one-dimensional case. Using a three-dimensional model, spatial-temporal development of laser pulse is investigated. Occurrence of some nonlinear phenomena such as self-focusing, self-modulation, light trapping, and filamentation of laser pulse is discussed. Also the effect of external magnetic field and plasma temperature on the nonlinear evolution of these phenomena is studied.

Sepehri Javan, N.; Adli, F. [Department of Physics, Faculty of Sciences, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil 56199-11367 (Iran, Islamic Republic of)] [Department of Physics, Faculty of Sciences, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil 56199-11367 (Iran, Islamic Republic of)

2013-06-15T23:59:59.000Z

92

Loss of spatial coherence and limiting of focal plane intensity by small-scale laser-beam filamentation  

SciTech Connect (OSTI)

We describe a nonlinear optical mechanism that leads to a decrease of the degree of (transverse) spatial coherence of a laser beam as a function of propagation distance. This prediction is in direct contrast with those of the van Cittert-Zernike theorem, which applies to propagation through a linear, homogeneous material. The mechanism by which coherence is lost is the growth of small phase irregularities initially present on the laser wave front. We develop a detailed theoretical model of this effect and present experimental results that validate this model. The practical importance of this result is that by being able to controllably decrease the spatial coherence of a laser beam, one can limit the maximum intensity that is produced in its focal region. By limiting the intensity, one can prevent laser damage to bulk optical components or to sensitive photodetectors. This mechanism thus provides an alternative to current approaches of sensor protection based on optical power limiting.

Schweinsberg, Aaron; Kuper, Jerry [The Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); Boyd, Robert W. [The Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627 (United States); Department of Physics and School of Electrical Engineering and Computer Science, University of Ottawa, Ottawa, Ontario, Canda K1N 6N5 (Canada)

2011-11-15T23:59:59.000Z

93

Evidence for ultra-fast heating in intense-laser irradiated reduced-mass targets  

SciTech Connect (OSTI)

We report on an experiment irradiating individual argon droplets of 20 {mu}m diameter with laser pulses of several Joule energy at intensities of 10{sup 19} W/cm{sup 2}. K-shell emission spectroscopy was employed to determine the hot electron energy fraction and the time-integrated charge-state distribution. Spectral fitting indicates that bulk temperatures up to 160 eV are reached. Modelling of the hot-electron relaxation and generation of K-shell emission with collisional hot-electron stopping only is incompatible with the experimental results, and the data suggest an additional ultra-fast (sub-ps) heating contribution. For example, including resistive heating in the modelling yields a much better agreement with the observed final bulk temperature and qualitatively reproduces the observed charge state distribution.

Neumayer, P.; Gumberidze, A.; Hochhaus, D. C. [ExtreMe Matter Institute EMMI and Research Division, GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany); Frankfurt Institute for Advanced Studies FIAS, 60438 Frankfurt am Main (Germany); Aurand, B.; Stoehlker, T. [Helmholtzzentrum fuer Schwerionenforschung GSI, 64291 Darmstadt (Germany); Helmholtz Institute Jena, 07743 Jena (Germany); Costa Fraga, R. A.; Kalinin, A. [Institut fuer Kernphysik, J. W. Goethe University Frankfurt, 60438 Frankfurt am Main (Germany); Ecker, B. [Johannes Gutenberg University Mainz, 55099 Mainz (Germany); Helmholtz Institute Jena, 07743 Jena (Germany); Grisenti, R. E. [Institut fuer Kernphysik, J. W. Goethe University Frankfurt, 60438 Frankfurt am Main (Germany); Helmholtzzentrum fuer Schwerionenforschung GSI, 64291 Darmstadt (Germany); Kaluza, M. C. [Helmholtz Institute Jena, 07743 Jena (Germany); IOQ Institute of Optics and Quantum Electronics, University of Jena (Germany); Kuehl, T. [Johannes Gutenberg University Mainz, 55099 Mainz (Germany); Helmholtzzentrum fuer Schwerionenforschung GSI, 64291 Darmstadt (Germany); Helmholtz Institute Jena, 07743 Jena (Germany); Polz, J. [IOQ Institute of Optics and Quantum Electronics, University of Jena (Germany); Reuschl, R. [ExtreMe Matter Institute EMMI and Research Division, GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany); Winters, D.; Winters, N.; Yin, Z. [Helmholtzzentrum fuer Schwerionenforschung GSI, 64291 Darmstadt (Germany)

2012-12-15T23:59:59.000Z

94

Laser-matter interaction at intensities of 10 sup 12 W/cm sup 2 and below  

SciTech Connect (OSTI)

For single pulsed laser-matter interactions at sufficiently high intensity, the electron density in the ablated vapor is large enough to absorb the laser radiation before it can reach the dense target material. The resulting interaction can be described in terms of energy flows: laser energy is absorbed in the plasma in front of the target and reappears as thermal electron energy and secondary radiation, part of which impinges upon and heats the dense target material at the dense material-vapor interface. This heating in turn drives ablation, thereby providing a self-consistent mass source for the laser absorption, energy conversion, and transmission. Under typical conditions of laser intensity, pulse width and spot size, the flow patterns can be strongly two-dimensional. We have modified the inertial confinement fusion code LASNEX to simulate gaseous and some dense material aspects for the relatively low intensity, long-pulse-length conditions to interest in many laser-related applications. The unique aspect to our treatment consists of an ablation model which defines a dense material vapor interface and then calculates the mass flow across this interface. The model, at present, treats the dense material as a rigid, two-dimensional simulational mass and heat reservoir, suppressing all hydrodynamical motion in the dense material. The modeling is being developed and refined through simulation of experiments, as well as through the investigation of internal inconsistencies, and some simulations of model problems. 5 refs., 14 figs., 1 tab.

Goldman, S.R.; Dingus, R.S.; Kirkpatrick, R.C.; Kopp, R.A.; Stover, E.K.; Watt, R.G.

1990-01-01T23:59:59.000Z

95

Northwestern Researchers Develop Bistable Nanoswitch Science Daily --Carbon nanotubes (CNT) have been under intense study by  

E-Print Network [OSTI]

Northwestern Researchers Develop Bistable Nanoswitch Science Daily -- Carbon nanotubes (CNT) have been under intense study by scientists all over the world for more than a decade and are being thought with high-aspect ratio, carbon nanotubes have emerged as a promising material because of their many

Espinosa, Horacio D.

96

Electron generation and transport in intense relativistic laser-plasma interactions relevant to fast ignition ICF  

E-Print Network [OSTI]

as a step towards laser fusion ignition, Nature, 412 (2001),tip. Full scale fast ignition laser systems are envisionedmodified. Full scale fast ignition laser systems of 100 kJ

Ma, Tammy Yee Wing

2010-01-01T23:59:59.000Z

97

Fusion Generated Fast Particles by Laser Impact on Ultra-Dense Deuterium: Rapid Variation with Laser Intensity  

Science Journals Connector (OSTI)

Nuclear fusion D+D processes are studied by nanosecond pulsed laser interaction with ultra-dense deuterium. This material...29 cm?3 as shown in several previous publications. Laser power is <2 W (0.2 J pulses) an...

Patrik U. Andersson; Leif Holmlid

2012-06-01T23:59:59.000Z

98

Electron acceleration by an intense short pulse laser in a static magnetic field in vacuum K. P. Singh*  

E-Print Network [OSTI]

Electron acceleration by an intense short pulse laser in a static magnetic field in vacuum K. P 2003; revised manuscript received 22 December 2003; published 28 May 2004) Electron acceleration the peak of the pulse interacts with the electron and the direction of the static magnetic field is taken

Roy, Subrata

99

The Science DMZ: A Network Design Pattern for Data-Intensive Science  

SciTech Connect (OSTI)

The ever-increasing scale of scientific data has become a significant challenge for researchers that rely on networks to interact with remote computing systems and transfer results to collaborators worldwide. Despite the availability of high-capacity connections, scientists struggle with inadequate cyberinfrastructure that cripples data transfer performance, and impedes scientific progress. The Science DMZ paradigm comprises a proven set of network design patterns that collectively address these problems for scientists. We explain the Science DMZ model, including network architecture, system configuration, cybersecurity, and performance tools, that creates an optimized network environment for science. We describe use cases from universities, supercomputing centers and research laboratories, highlighting the effectiveness of the Science DMZ model in diverse operational settings. In all, the Science DMZ model is a solid platform that supports any science workflow, and flexibly accommodates emerging network technologies. As a result, the Science DMZ vastly improves collaboration, accelerating scientific discovery.

Dart, Eli; Rotman, Lauren; Tierney, Brian; Hester, Mary; Zurawski, Jason

2013-08-13T23:59:59.000Z

100

Sensitivity to Dark Energy candidates by searching for four-wave mixing of high-intensity lasers in the vacuum  

E-Print Network [OSTI]

Theoretical challenges to understand Dark Matter and Dark Energy suggest the existence of low-mass and weakly coupling fields in the universe. The quasi-parallel photon-photon collision system (QPS) can provide chances to probe the resonant production of these light dark fields and the induced decay by the coherent nature of laser fields simultaneously. By focusing high-intensity lasers with different colors in the vacuum, new colors emerge as the signature of the interaction. Because four photons in the initial and final states interplay via the dark field exchange, this process is analogous to four-wave mixing in quantum optics, where the frequency sum and difference among the incident three waves generate the fourth wave with a new frequency via the nonlinear property of crystals. The interaction rate of the four-wave mixing process has the cubic dependence on the intensity of each wave. Therefore, if high-intensity laser fields are given, the sensitivity to the weakly coupling of dark fields to photons rapidly increases over the wide mass range below sub-eV. Based on the experimentally measurable photon energies and the linear polarization states, we formulate the relation between the accessible mass-coupling domains and the high-intensity laser parameters, where the effects of the finite spectrum width of pulse lasers are taken into account. The expected sensitivity suggests that we have a potential to explore interactions at the Super-Planckian coupling strength in the sub-eV mass range, if the cutting-edge laser technologies are properly combined.

Kensuke Homma

2012-11-12T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Data Intensive  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Data Intensive Data Intensive Computing Pilot Program In 2014 NERSC is conducting its second and last round of allocations to projects in data intensive science. This pilot aims to...

102

Analysis of two-dimensional high-energy photoelectron momentum distributions in the single ionization of atoms by intense laser pulses  

E-Print Network [OSTI]

, using longer pulses at lower intensities. The energy spectra above 4Up, where Up is the ponderomotive energy, have been found to vary rapidly with small changes in laser intensities 10,11 when laser pulseAnalysis of two-dimensional high-energy photoelectron momentum distributions in the single

Lin, Chii-Dong

103

CRC handbook of laser science and technology. Volume 3. Gas lasers  

SciTech Connect (OSTI)

This book describes the fundamentals of gas lasers. It provides information and data on neutral gas lasers, ionized gas lasers, and molecular gas lasers. Concluding this volume is an extensive table of all gas laser wavelengths.

Weber, M.J.

1982-01-01T23:59:59.000Z

104

ChemCam rock laser for Mars Science Laboratory "Curiosity"  

ScienceCinema (OSTI)

Los Alamos has a long history of space-related instruments, tied primarily to its role in defense-related treaty verification. Space-based detectors have helped determine the differences between signals from lightning bolts and potential nuclear explosions. LANL-developed gamma-ray detection instruments first revealed the existence of what we now know as gamma-ray bursts, an exciting area of astrophysical research. And the use of LANL instruments on varied space missions continues with such products as the ChemCam rock laser for NASA, shown here. The Engineering Model of the ChemCam Mars Science Laboratory rover instrument arrived at NASA's Jet Propulsion Laboratory on February 6, 2008. The Flight Model was shipped in August, 2010 for installation on the rover at JPL. ChemCam will use imaging and laser-induced breakdown spectroscopy (LIBS) to determine rock and soil compositions on Mars, up to 9 meters from the rover. The engineering model is being integrated into the rover test bed for the development and testing of the rover software. The actual flight model components were concurrently assembled at Los Alamos and in Toulouse, France. The Mars Science Laboratory is scheduled to launch in 2011. Animations courtesy of JPL/NASA.

Wiens, Roger

2014-08-12T23:59:59.000Z

105

Neutron production from interactions of high-intensity ultrashort pulse laser with a planar deuterated polyethylene target  

SciTech Connect (OSTI)

The deuteron acceleration from a planar uniform deuterated polyethylene (CD{sub 2}) target was studied with a two-dimensional electromagnetic particle-in-cell method in the ultrarelativistic regime for peak laser intensities between 10{sup 23} and 10{sup 25} W/m{sup 2}. Under identical conditions the deuteron energy and angular distributions are very different when compared to that produced from a double-layer target. The neutron production from D(d,n)-{sup 3}He nuclear fusion reactions was also investigated with a three-dimensional Monte Carlo ion beam-target deposition model. The neutron yield and its angular distribution were studied as a function of peak laser intensity and laser pulse duration. A neutron yield of 10{sup 4}-10{sup 6} neutrons per Joule laser energy is inferred from simulations of a 4 {mu}m thick planar uniform CD{sub 2} target. The angular scattering of neutrons is found to be nonisotropic and has a significant component in the forward (laser propagation) direction.

Petrov, G. M.; Davis, J. [Naval Research Laboratory, Plasma Physics Division, 4555 Overlook Avenue SW, Washington, D.C. 20375 (United States)

2008-07-15T23:59:59.000Z

106

Neutron production from 7Li(d,xn) nuclear fusion reactions driven by high-intensity laser–target interactions  

Science Journals Connector (OSTI)

Numerical simulations of neutron production from deuterium–lithium nuclear fusion reactions have been performed. A set of differential cross sections for the 7Li(d,xn) reaction for incident deuteron energies of up to 50?MeV is assembled. The angular distribution of neutrons from a thick lithium target is simulated and benchmarked against experimental data. Two-stage neutron production from laser–target experiments has been studied as a function of laser intensity and energy. During the first stage a well collimated deuteron beam is generated using a high-intensity ultrashort pulse laser. During the second stage it is transported through a lithium target using a 3D Monte-Carlo ion beam–target deposition model. The neutron yield is estimated to be ~108?neutrons?J?1 laser energy. Some 1010 neutrons can be expected from a ~100?J petawatt-class laser. For incident deuteron energies above 1?MeV the proposed scheme for neutron production from d–Li reactions is superior to that from d–d reactions, producing a collimated beam of neutrons with higher neutron yield.

J Davis; G M Petrov; Tz Petrova; L Willingale; A Maksimchuk; K Krushelnick

2010-01-01T23:59:59.000Z

107

Continuation of full-scale three-dimensional numerical experiments on high-intensity particle and laser beam-matter interactions  

SciTech Connect (OSTI)

We present results from the grant entitled, ���¢��������Continuation of full-scale three-dimensional numerical experiments on high-intensity particle and laser beam-matter interactions.���¢������� The research significantly advanced the understanding of basic high-energy density science (HEDS) on ultra intense laser and particle beam plasma interactions. This advancement in understanding was then used to to aid in the quest to make 1 GeV to 500 GeV plasma based accelerator stages. The work blended basic research with three-dimensions fully nonlinear and fully kinetic simulations including full-scale modeling of ongoing or planned experiments. The primary tool was three-dimensional particle-in-cell simulations. The simulations provided a test bed for theoretical ideas and models as well as a method to guide experiments. The research also included careful benchmarking of codes against experiment. High-fidelity full-scale modeling provided a means to extrapolate parameters into regimes that were not accessible to current or near term experiments, thereby allowing concepts to be tested with confidence before tens to hundreds of millions of dollars were spent building facilities. The research allowed the development of a hierarchy of PIC codes and diagnostics that is one of the most advanced in the world.

Mori, Warren, B.

2012-12-01T23:59:59.000Z

108

Laser enhanced high-intensity focused ultrasound thrombolysis: An in vitro study  

E-Print Network [OSTI]

radiation, and ultrasound and laser parameters were optimized to achieve better thrombolysis efficiency. The results indicated that the thrombolysis efficiency increased when pulse length of HIFU wave, HIFU pressure, or laser fluence increases. Also...

Cui, Huizhong; Yang, Xinmai

2013-01-17T23:59:59.000Z

109

Monte Carlo calculations of pair production in high-intensity laser-plasma interactions  

E-Print Network [OSTI]

Gamma-ray and electron-positron pair production will figure prominently in laser-plasma experiments with next generation lasers. Using a Monte Carlo approach we show that straggling effects arising from the finite recoil an electron experiences when it emits a high energy photon, increase the number of pairs produced on further interaction with the laser fields.

Roland Duclous; John Kirk; Anthony Bell

2010-10-21T23:59:59.000Z

110

Phase control of the photofragment branching ratio of the HI molecule in two intense few-cycle laser pulses  

Science Journals Connector (OSTI)

A time-dependent quantum wave packet method is used to calculate the branching ratio of photodissociation products of the HI molecule in two-color intense few-cycle laser pulses with varying relative phase. It is demonstrated that the relative phase between two intense few-cycle pulses (? and 2?) can be used for controlling the branching ratio of the photodissociation products I(P3?22) and I(P1?22) of the HI molecule. The nonadiabatic effect of the crossing potential energy curves on the photodissociation product yields of the HI molecule is also discussed.

Sen-Ming Wang; Kai-Jun Yuan; Ying-Yu Niu; Yong-Chang Han; Shu-Lin Cong

2006-10-11T23:59:59.000Z

111

Generation of high-quality mega-electron volt proton beams with intense-laser-driven nanotube accelerator  

SciTech Connect (OSTI)

An ion acceleration scheme using carbon nanotubes (CNTs) is proposed, in which embedded fragments of low-Z materials are irradiated by an ultrashort intense laser to eject substantial numbers of electrons. Due to the resultant characteristic electrostatic field, the nanotube and embedded materials play the roles of the barrel and bullets of a gun, respectively, to produce highly collimated and quasimonoenergetic ion beams. Three-dimensional particle simulations, that take all the two-body Coulomb interactions into account, demonstrate generation of quasimonoenergetic MeV-order proton beams using nanometer-size CNT under a super-intense electrostatic field {approx}10{sup 14} V m{sup -1}.

Murakami, M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan)] [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Tanaka, M. [Department of Engineering, Chubu University, Aichi 487-8501 (Japan)] [Department of Engineering, Chubu University, Aichi 487-8501 (Japan)

2013-04-22T23:59:59.000Z

112

Increasing the upper-limit intensity and temperature range for thermal self-focusing of a laser beam by using plasma density ramp-up  

SciTech Connect (OSTI)

This work is devoted to improving relativistic and ponderomotive thermal self-focusing of the intense laser beam in an underdense plasma. It is shown that the ponderomotive nonlinearity induces a saturation mechanism for thermal self-focusing. Therefore, in addition to the well-known lower-limit critical intensity, there is an upper-limit intensity for thermal self-focusing above which the laser beam starts to experience ponderomotive defocusing. It is indicated that the upper-limit intensity value is dependent on plasma and laser parameters such as the plasma electron temperature, plasma density, and laser spot size. Furthermore, the effect of the upward plasma density ramp profile on the thermal self-focusing is studied. Results show that by using the plasma density ramp-up, the upper-limit intensity increases and the self-focusing temperature range expands.

Bokaei, B.; Niknam, A. R., E-mail: a-niknam@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of)

2014-03-15T23:59:59.000Z

113

Proceedings of the workshop on the science of intense radioactive ion beams  

SciTech Connect (OSTI)

This report contains the proceedings of a 2-1/2 day workshop on the Science of Intense Radioactive Ion Beams which was held at the Los Alamos National Laboratory on April 10--12, 1990. The workshop was attended by 105 people, representing 30 institutions from 10 countries. The thrust of the workshop was to develop the scientific opportunities which become possible with a new generation intense Radioactive Ion Beam (RIB) facility, currently being discussed within North America. The workshop was organized around five primary topics: (1) reaction physics; (2) nuclei far from stability/nuclear structure; (3) nuclear astrophysics; (4) atomic physics, material science, and applied research; and (5) facilities. Overview talks were presented on each of these topics, followed by 1-1/2 days of intense parallel working group sessions. The final half day of the workshop was devoted to the presentation and discussion of the working group summary reports, closing remarks and a discussion of future plans for this effort.

McClelland, J.B.; Vieira, D.J. (comps.)

1990-10-01T23:59:59.000Z

114

High-intensity laser-driven proton acceleration: influence of pulse contrast  

Science Journals Connector (OSTI)

...inset of figure 3. CR-39 nuclear track detector, which is...pump down cycle of the target vacuum chamber. The proton stopping...hadrontherapy with laser ion accelerators. Phys. Lett. A. 299...laser virtual-cathode plasma accelerator. Phys. Rev. Lett. 92...

2006-01-01T23:59:59.000Z

115

Hydrodynamic Scaling Analysis of Nuclear Fusion driven by ultra-intense laser-plasma interactions  

E-Print Network [OSTI]

We discuss scaling laws of fusion yields generated by laser-plasma interactions. The yields are found to scale as a function of the laser power. The origin of the scaling law in the laser driven fusion yield is derived in terms of hydrodynamic scaling. We point out that the scaling properties can be attributed to the laser power dependence of three terms: the reaction rate, the density of the plasma and the projected range of the plasma particle in the target medium. The resulting scaling relations have a predictive power that enables estimating the fusion yield for a nuclear reaction which has not been investigated by means of the laser accelerated ion beams.

Sachie Kimura; Aldo Bonasera

2011-09-23T23:59:59.000Z

116

Inertial fusion energy issues of intense heavy ion and laser beams interacting with ionized matter studied at GSI-Darmstadt  

Science Journals Connector (OSTI)

European activities on inertial fusion energy are coordinated by “keep in touch activities” of the European Fusion Programme coordinated by the European Commission. There is no general inertial fusion program in Europe. Instead, a number of activities relevant to inertial fusion are carried out by university groups and research centers. The Helmholtz-Research Center GSI-Darmstadt (Gesellschaft für Schwerionenforschung) operates accelerator facilities which provide the highest intensity for heavy ion beams and therefore key issues of ion beam driven fusion can be addressed. In addition to the accelerator facilities, one high-energy laser system is available (nhelix: nanosecond high-energy laser for ion experiments) and another one is under construction (PHELIX: petawatt high-energy laser for ion experiments). The heavy ion synchrotron facility, SIS18 (Schwer-Ionen-Synchrotron 18) recently delivered an intense uranium beam that deposits about 1 kJ/g specific energy in solid matter. Using this beam, experiments have been performed where solid Pb- and Ta-targets have been heated to the level of 1 eV. Experiments to study interaction mechanism of heavy ion beams with matter have been continued and are reported here.

D.H.H. Hoffmann; A. Blazevic; S. Korostiy; P. Ni; S.A. Pikuz; B. Rethfeld; O. Rosmej; M. Roth; N.A. Tahir; S. Udrea; D. Varentsov; K. Weyrich; B.Yu. Sharkov; Y. Maron

2007-01-01T23:59:59.000Z

117

#LabChat: Particle Accelerators, Lasers and Discovery Science, May 17 at  

Broader source: Energy.gov (indexed) [DOE]

Particle Accelerators, Lasers and Discovery Science, May Particle Accelerators, Lasers and Discovery Science, May 17 at 1pm EST #LabChat: Particle Accelerators, Lasers and Discovery Science, May 17 at 1pm EST May 15, 2012 - 2:03pm Addthis SLAC’s linac accelerates very short pulses of electrons to 99.9999999 percent the speed of light through a slalom that causes the electrons to emit X-rays, which become synchronized as they interact with the electron pulses and create the world’s brightest X-ray laser pulse. | Photo by Brad Plummer, SLAC. SLAC's linac accelerates very short pulses of electrons to 99.9999999 percent the speed of light through a slalom that causes the electrons to emit X-rays, which become synchronized as they interact with the electron pulses and create the world's brightest X-ray laser pulse. | Photo by

118

Using X-ray free-electron lasers for probing of complex interaction dynamics of ultra-intense lasers with solid matter  

SciTech Connect (OSTI)

We demonstrate the potential of X-ray free-electron lasers (XFEL) to advance the understanding of complex plasma dynamics by allowing for the first time nanometer and femtosecond resolution at the same time in plasma diagnostics. Plasma phenomena on such short timescales are of high relevance for many fields of physics, in particular in the ultra-intense ultra-short laser interaction with matter. Highly relevant yet only partially understood phenomena become directly accessible in experiment. These include relativistic laser absorption at solid targets, creation of energetic electrons and electron transport in warm dense matter, including the seeding and development of surface and beam instabilities, ambipolar expansion, shock formation, and dynamics at the surfaces or at buried layers. In this paper, we focus on XFEL plasma probing for high power laser matter interactions based on quantitative calculations using synthesized data and evaluate the feasibility of various imaging and scattering techniques with special focus on the small angle X-ray scattering technique.

Kluge, T., E-mail: t.kluge@hzdr.de; Huang, L. G.; Metzkes, J.; Bussmann, M. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany)] [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Gutt, C. [Universität Siegen, D-57068 Siegen (Germany)] [Universität Siegen, D-57068 Siegen (Germany); Schramm, U.; Cowan, T. E. [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany) [Helmholtz-Zentrum Dresden-Rossendorf e.V., D-01328 Dresden (Germany); Technische Universität Dresden, D-01062 Dresden (Germany)

2014-03-15T23:59:59.000Z

119

Relative phase interactions of two copropagating laser beams in underdense plasmas at different intensities and spot sizes  

SciTech Connect (OSTI)

The mutual interactions of two copropagating laser beams at a relative phase are studied using a two-dimensional fluid code. The interactions are investigated in underdense plasma at selected beam configurations and beam parameters for two separate nonlinearities, i.e., the ponderomotive and the relativistic nonlinearity. The selected beam configurations are introduced by different initial transverse spot size perturbations (finite and infinite) and different initial transversal intensity distributions (nonuniform and uniform) over those spot sizes and the selected beam parameters are given by different initial beam intensities relevant to each nonlinearity. In the ponderomotive nonlinearity, simulation results show that no mutual interactions are demonstrated between the copropagating beams regardless of the initial beam configurations and parameters. In nonlinear relativistic simulations, the mutual interactions between the beams are clearly observed, a mutual repulsion is formed in the presence of initial intensities that are nonuniformly distributed over finite spot sizes, and an effective strongly modulated mutual attraction takes places in the presence of initial intensities that are uniformly distributed over infinite spot sizes. Moreover, it is found in these simulations that increasing the initial beam intensities improves the attraction properties between the copropagationg beams.

Mahdy, A. I. [Department of Plasma and Nuclear Fusion, Nuclear Research Centre, Atomic Energy Authority, 13759 Cairo (Egypt)

2010-06-15T23:59:59.000Z

120

Study of 1–8 keV K-? x-ray emission from high intensity femtosecond laser produced plasma  

SciTech Connect (OSTI)

We report an experimental study on the optimization of a laser plasma based x-ray source of ultra-short duration K-? line radiation. The interaction of pulses from a CPA based Ti:sapphire laser (10 TW, 45 fs, 10 Hz) system with magnesium, titanium, iron and copper solid target generates bright 1-8 keV K-? x-ray radiation. The x-ray yield was optimized with the laser pulse duration (at fixed fluence) which is varied in the range of 45 fs to 1.4 ps. It showed a maximum at laser pulse duration of ?740 fs, 420 fs, 350 and 250 fs for Mg (1.3 keV), Ti (4.5 keV), Fe (6.4 keV) and Cu (8.05 keV) respectively. The x-ray yield is observed to be independent of the sign of the chirp. The scaling of the K-? yield (I{sub x} ? I{sub L}{sup ?}) for 45 fs and optimized pulse duration were measured for laser intensities in the region of 3 × 10{sup 14} – 8 × 10{sup 17}. The x-ray yield shows a much faster scaling exponent ? = 1.5, 2.1, 2.4 and 2.6 for Mg, Ti, Fe and Cu respectively at optimized pulse duration compared to scaling exponent of 0.65, 1.3, 1.5, and 1.7 obtained for 45 fs duration laser pulses. The laser to x-ray energy conversion efficiencies obtained for different target materials are ?{sub Mg} = 1.2 × 10{sup ?5}, ?{sub Ti} = 3.1 × 10{sup ?5}, ?{sub Fe} = 2.7 × 10{sup ?5}, ?{sub Cu} = 1.9 × 10{sup ?5}. The results have been explained from the efficient generation of optimal energy hot electrons at longer laser pulse duration. The faster scaling observed at optimal pulse duration indicates that the x-ray source is generated at the target surface and saturation of x-ray emission would appear at larger laser fluence. An example of utilization of the source for measurement of shock-wave profiles in a silicon crystal by time resolved x-ray diffraction is also presented.

Arora, V., E-mail: arora@rrcat.gov.in; Naik, P. A.; Chakera, J. A.; Bagchi, S.; Tayyab, M.; Gupta, P. D. [Laser Plasma Division, Raja Rammana Centre for Advanced Technology, Indore 452 013 (India)] [Laser Plasma Division, Raja Rammana Centre for Advanced Technology, Indore 452 013 (India)

2014-04-15T23:59:59.000Z

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121

Free Electron Laser Program Program at TJNAF| U.S. DOE Office of Science  

Office of Science (SC) Website

Free Electron Laser Program Program at Free Electron Laser Program Program at TJNAF Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Free Electron Laser Program Program at TJNAF Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Free Electron Laser (FEL) Program Developed at: Thomas Jefferson National Laboratory Developed in: 1990's - 2010

122

Efficient laser acceleration of proton beams for intense sources of low energy neutrinos  

SciTech Connect (OSTI)

The existence of highly efficient ion acceleration regimes in collective laser-plasma interactions opens up the possibility to develop high-energy-physics (HEP) facilities in conjunction with projects for inertial confined nuclear fusion (ICF) and neutron spallation sources.

Pegoraro, F. [Department of Physics, University of Pisa, Pisa (Italy); CNISM, Pisa (Italy); Bulanov, S. V.; Esirkepov, T. Zh.; Tajima, T. [Advanced Photon Research Centre, JAEA, Kizu, Kyoto (Japan); Migliozzi, P. [INFN, Sez. di Napoli, Naples (Italy); Terranova, F. [INFN, Laboratori Nazionali di Frascati, Frascati (Italy)

2006-04-07T23:59:59.000Z

123

Plasma density ramp for relativistic self-focusing of an intense laser  

Science Journals Connector (OSTI)

It is known that a high-power laser propagating through an underdense plasma can acquire a minimum spot size due to relativistic self-focusing. Beyond the focus, the nonlinear...

Gupta, Devki N; Hur, Min S; Hwang, Ilmoon; Suk, Hyyong; Sharma, Ashok K

2007-01-01T23:59:59.000Z

124

Selective Dissociation of Sulfur Hexafluoride by Intense CO2 Laser Radiation in Pulsed Gas Dynamic Flow  

Science Journals Connector (OSTI)

Isotopically selective IR multiphoton dissociation (MPD) of SF6 in a pulsed gas dynamic flow was studied. The dependence of the yield of the product SF4 on the frequency of CO2 laser radiation exciting SF6 molecu...

G. N. Makarov; A. N. Petin

2000-11-01T23:59:59.000Z

125

Application of a Prism Dye Laser for Enhanced Single-Shot CARS Intensities  

Science Journals Connector (OSTI)

During the last decades several laser-based techniques have been developed for the diagnostics of combustion processes—an area in which features such as their high temporal and...

Aldén, Marcus; Bengtsson, Per-Erik; Neij, Hans; Nilsson, Anders

1993-01-01T23:59:59.000Z

126

Electron Generation and Transport in Intense Relativistic Laser-Plasma Interactions Relevant to Fast Ignition ICF  

SciTech Connect (OSTI)

The reentrant cone approach to Fast Ignition, an advanced Inertial Confinement Fusion scheme, remains one of the most attractive because of the potential to efficiently collect and guide the laser light into the cone tip and direct energetic electrons into the high density core of the fuel. However, in the presence of a preformed plasma, the laser energy is largely absorbed before it can reach the cone tip. Full scale fast ignition laser systems are envisioned to have prepulses ranging between 100 mJ to 1 J. A few of the imperative issues facing fast ignition, then, are the conversion efficiency with which the laser light is converted to hot electrons, the subsequent transport characteristics of those electrons, and requirements for maximum allowable prepulse this may put on the laser system. This dissertation examines the laser-to-fast electron conversion efficiency scaling with prepulse for cone-guided fast ignition. Work in developing an extreme ultraviolet imager diagnostic for the temperature measurements of electron-heated targets, as well as the validation of the use of a thin wire for simultaneous determination of electron number density and electron temperature will be discussed.

Ma, T

2010-04-21T23:59:59.000Z

127

Multiphoton Double Ionization of Ar in Intense Extreme Ultraviolet Laser Fields Studied by Shot-by-Shot Photoelectron Spectroscopy  

SciTech Connect (OSTI)

Photoelectron spectroscopy has been performed to study the multiphoton double ionization of Ar in an intense extreme ultraviolet laser field (h{nu}{approx}21 eV, {approx}5 TW/cm{sup 2}), by using a free electron laser (FEL). Three distinct peaks identified in the observed photoelectron spectra clearly show that the double ionization proceeds sequentially via the formation of Ar{sup +}: Ar+h{nu}{yields}Ar{sup +}+e{sup -} and Ar{sup +}+2h{nu}{yields}Ar{sup 2+}+e{sup -}. Shot-by-shot recording of the photoelectron spectra allows simultaneous monitoring of FEL spectrum and the multiphoton process for each FEL pulse, revealing that the two-photon ionization from Ar{sup +} is significantly enhanced by intermediate resonances in Ar{sup +}.

Hikosaka, Y. [Department of Environmental Science, Niigata University, Niigata 950-2181 (Japan); Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585 (Japan); Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585 (Japan); RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Fushitani, M.; Hishikawa, A. [Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585 (Japan); Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585 (Japan); RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602 (Japan); Matsuda, A. [Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585 (Japan); RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602 (Japan); Tseng, C.-M. [Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585 (Japan); RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Shigemasa, E. [Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585 (Japan); Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585 (Japan); RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Nagasono, M.; Tono, K.; Yabashi, M.; Ishikawa, T. [RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Togashi, T.; Ohashi, H.; Kimura, H. [RIKEN, XFEL Project Head Office, Sayo, Hyogo 679-5148 (Japan); Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198 (Japan); Senba, Y. [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198 (Japan)

2010-09-24T23:59:59.000Z

128

D–D nuclear fusion induced by laser-generated plasma at 1016 W cm?2 intensity  

Science Journals Connector (OSTI)

Deuterated polyethylene targets (CD2-monomer), as thin and thick films, were laser irradiated in a vacuum at 1016 W cm?2 intensity. The produced plasma was monitored in situ using the Thomson parabola spectrometer, ion collectors and SiC semiconductor detectors. For thin targets irradiated under target-normal-sheath-acceleration conditions, laser accelerated deuterons with energies higher than 3.0 MeV were measured along the normal to the target surface. Characteristic emissions at 3.0 and 2.5 MeV for protons and neutrons, respectively, have been detected confirming the production of nuclear fusion events. The evidence of nuclear fusion effects was evaluated and discussed.

Lorenzo Torrisi; Salvatore Cavallaro; Maria Cutroneo; Josef Krasa; Daniel Klir

2014-01-01T23:59:59.000Z

129

Lagrangian Formulation of Relativistic Particle Average Motion in a Laser Field of Arbitrary Intensity  

SciTech Connect (OSTI)

The Lagrangian and Hamiltonian functions describing average motion of a relativistic particle under the action of intensive high-frequency electromagnetic radiation are obtained. In weak, low-frequency background fields, such a particle on average drifts with an effective, relativistically invariant mass, which depends on the intensity of the electromagnetic field.

I.Y. Dodin; N.J. Fisch; G.M. Fraiman

2003-02-06T23:59:59.000Z

130

Effect of Nuclear Motion on Molecular High-Order Harmonics and on Generation of Attosecond Pulses in Intense Laser Pulses  

SciTech Connect (OSTI)

We calculate harmonic spectra and shapes of attosecond-pulse trains using numerical solutions of Non-Born-Oppenheimer time-dependent Shroedinger equation for 1D H{sub 2} molecules in an intense laser pulse. A very strong signature of nuclear motion is seen in the time profiles of high-order harmonics. In general the nuclear motion shortens the part of the attosecond-pulse train originating from the first electron contribution, but it may enhance the second electron contribution for longer pulses. The shape of time profiles of harmonics can thus be used for monitoring the nuclear motion.

Bandrauk, Andre D.; Chelkowski, Szczepan; Kawai, Shinnosuke; Lu, Huizhong [Departement de Chimie, Universite de Sherbrooke, Sherbrooke, Qc, J1K 2R1 (Canada)

2008-10-10T23:59:59.000Z

131

Spectrally resolved near-field intensity measurements from gain-guided twin-stripe laser diode arrays. Technical report  

SciTech Connect (OSTI)

Gain-guided twin-stripe laser diodes were observed that exhibit two distinct sets of longitudinal modes, one corresponding to a single near-field intensity profile centered between the stripes and the other to a double-lobe near-field distribution centered under the stripes. A large spectral separation between these two sets of modes was also measured. The double-lobe distribution probably results from a weak index guide, which occurs because of the decrease in the current density between stripes. The spectral separation between these two near-field modes is believed to be due to band filling.

Heflinger, D.G.; Fenner, W.R.

1988-11-01T23:59:59.000Z

132

Dynamical ionization ignition of clusters in intense and short laser pulses  

E-Print Network [OSTI]

The electron dynamics of rare gas clusters in laser fields is investigated quantum mechanically by means of time-dependent density functional theory. The mechanism of early inner and outer ionization is revealed. The formation of an electron wave packet inside the cluster shortly after the first removal of a small amount of electron density is observed. By collisions with the cluster boundary the wave packet oscillation is driven into resonance with the laser field, hence leading to higher absorption and ionization. Although the mechanism is sensitive to the laser frequency, any plasma resonances are found to be insignificant for the cluster sizes, the short pulse durations, and the modest charge states under consideration.

Bauer, D

2003-01-01T23:59:59.000Z

133

Two-color phase control of high-order harmonic generation in intense laser fields  

E-Print Network [OSTI]

We present a time-independent generalized Floquet approach for nonperturbative treatment of high-order harmonic generation (HG) in intense onea (i) determination of the complex quasienergy eigenvalue and eigenfunction by means of the non...

Telnov, Dmitry A.; Wang, Jingyan; Chu, Shih-I

1995-11-01T23:59:59.000Z

134

Laser Telecommunication timeLaser beam  

E-Print Network [OSTI]

Laser Telecommunication Experiment Laser time Laser beam intensity timeLaser beam Laser battery Laser connected to a circuit without a modulator. Bottom graph illustrates what happen when a modulating signal is superimposed to the DC voltage driving the laser Laser beam intensity DC Input voltage DC

La Rosa, Andres H.

135

Quantum and semiclassical simulations in intense laser-H{sub 2}{sup +} interactions  

SciTech Connect (OSTI)

We present the results of a set of quantum and semiclassical simulations of the response of H{sub 2}{sup +} molecular ions, when submitted to a strong and ultrashort (femtosecond) infrared laser pulse. Going beyond the framework of the fixed nuclei (Born-Oppenheimer) approximation, we have addressed several questions related to the competition between excitation, dissociation, and ionization. In this context, it is shown that semiclassical simulations can provide valuable informations about the dynamics of the processes considered.

Ruiz, Camilo; Plaja, Luis [Departamento de Fisica Aplicada, Universidad de Salamanca, E-37008 Salamanca (Spain); Taieeb, Richard; Veniard, Valerie; Maquet, Alfred [Laboratoire de Chimie Physique-Matiere et Rayonnement, Universite Pierre et Marie Curie, 11, Rue Pierre et Marie Curie 75231 Paris Cedex 05 (France)

2006-06-15T23:59:59.000Z

136

Interaction of explosively driven dense plasmas with a low-intensity laser radiation  

Science Journals Connector (OSTI)

The results of first experiments on reflectivity of polarized light on an explosively driven dense xenon plasma are presented. The study of polarized reflectivity properties of the plasma was accomplished using a laser light of wavelength ? = 1064 nm and at incident angles ? = 0–30°. With density ? = 2.7 g cm?3, pressure P = 10.5 GPa and temperatures up to T ~ 3?104 K of the investigated plasma, conditions with strong Coulomb interaction (the nonideality parameter up to ? ~ 2.0) were present. Reflectivities, which were calculated via the Helmholtz equation incorporating a density profile for the plasma surface, are compared to the experimental results.

Yu Zaporozhets; V Mintsev; V Gryaznov; V Fortov; H Reinholz; G Röpke

2009-01-01T23:59:59.000Z

137

Electron-nuclear dynamics of the one-electron nonlinear polyatomic molecule H32+ in ultrashort intense laser pulses  

Science Journals Connector (OSTI)

A quantum description of the one-electron triangular H32+ molecular ion, beyond the Born-Oppenheimer approximation, is used to study the full influence of the nuclear motion on the high-intensity photoionization and harmonic generation processes. A detailed analysis of electron and proton motions and their time-dependent acceleration allows for identification of the main electron recollision events as a function of time-dependent configuration of the protons. High-order-harmonic generation photons are shown to be produced by single-electron recollision in the second half of the pulse envelope, which also induces a redshift in the harmonics, due to the rapid few-femtosecond motions of protons. Perpendicular harmonics are produced, in general, with a linearly polarized laser pulse parallel to a bond of the triangular molecule, and, in particular, the harmonics in the cutoff region are elliptically polarized. When the laser-pulse polarization is parallel to a symmetry axis of the triangular molecular ion, creation and destruction of the chemical bond perpendicular to the polarization is predicted on a near-femtosecond time scale.

C. Lefebvre; H. Z. Lu; S. Chelkowski; A. D. Bandrauk

2014-02-06T23:59:59.000Z

138

Generation of periodic ultrashort electron bunches and strongly asymmetric ion Coulomb explosion in nanometer foils interacting with ultra-intense laser pulse  

SciTech Connect (OSTI)

The interaction of a linearly polarized intense laser pulse with an ultrathin nanometer plasma layer is investigated to understand the physics of the ion acceleration. It is shown by the computer simulation that the plasma response to the laser pulse comprises two steps. First, due to the vxB effect, electrons in the plasma layer are extracted and periodic ultrashort relativistic electron bunches are generated every half of a laser period. Second, strongly asymmetric Coulomb explosion of ions in the foil occurs due to the strong electrostatic charge separation, once the foil is burnt through. Followed by the laser accelerated electron bunch, the ion expansion in the forward direction occurs along the laser beam that is much stronger as compared to the backward direction.

Tian Youwei [College of Mathematics and Physics, Nanjing University of Posts and Telecommunications, Nanjing 210003 (China); Yu Wei; Xu Han; Lei Anle; Shen Baifei; Wang Xin [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Lu Peixiang [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, Wuhan 430070 (China); Senecha, Vinod [Raja Ramanna Centre for Advanced Technology, Indore-452 013 (India)

2008-05-15T23:59:59.000Z

139

Compression and acceleration of electron bunches to high energies in the interference field of intense laser pulses with tilted amplitude fronts: concept and modelling  

SciTech Connect (OSTI)

A new concept of accelerating electrons by laser radiation is proposed, namely, direct acceleration by a laser field under the conditions of interference of several relativistic-intensity laser pulses with amplitude fronts tilted by the angle 45 Degree-Sign with respect to the phase fronts. Due to such interference the traps moving with the speed of light arise that capture the electrons, produced in the process of ionisation of low-density gas by the same laser radiation. The modelling on the basis of solving the relativistic Newton equation with the appropriate Lorenz force shows that these traps, moving in space, successively collect electrons from the target, compress the resulting electron ensemble in all directions up to the dimensions smaller than the wavelength of the laser radiation and accelerate it up to the energies of the order of a few GeV per electron. (extreme light fields and their applications)

Korobkin, V V; Romanovsky, Mikhail Yu; Trofimov, V A; Shiryaev, O B [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2013-03-31T23:59:59.000Z

140

Threshold shift and above-threshold multiphoton ionization of atomic hydrogen in intense laser fields  

E-Print Network [OSTI]

T is the kinetic energy of the electron. The effec- tive potential V,g is known as the pondermotive potential which can also be regarded as the average oscillating ener- gy of the electron in the field e~,. The latter is very small TABLE II. Intensity... becomes more and more im- portant compared to AEz as N increases or co decreases. The net result is that the ionization potential increases rapidly with both F and N . The disappearance of the lowest energy electrons in the xenon MPI-ATI experiment...

Chu, Shih-I; Cooper, J.

1985-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Visible fiber lasers for applications in Medical and Science  

Science Journals Connector (OSTI)

We will review the progress in watt level power fiber lasers in the visible range (520 to 780 nm range). We will then describe main applications in Ophthalmology (retinal...

Jacquemet, Mathieu; Mugnier, Alain; Lebref, Ronan; Pureur, David

142

Specific features of microheterogeneous plasma produced by irradiation of a polymer aerogel target with an intense 500-ps-long laser pulse  

Science Journals Connector (OSTI)

The properties of microheterogeneous plasma produced by irradiation of a polymer aerogel target with an intense (1014 W/cm3) short (0.5 ps) 1.064-?m laser pulse were studied. It is found that, even at plasma dens...

N. G. Borisenko; Yu. A. Merkul’ev; A. S. Orekhov; S. Chaurasia…

2013-08-01T23:59:59.000Z

143

Formation of silver nanoparticles inside a soda-lime glass matrix in the presence of a high intensity Ar{sup +} laser beam  

SciTech Connect (OSTI)

Formation and motion of the silver nanoparticles inside an ion-exchanged soda-lime glass in the presence of a focused high intensity continuous wave Ar{sup +} laser beam (intensity: 9.2 x 10{sup 4} W/cm{sup 2}) have been studied in here. One-dimensional diffusion equation has been used to model the diffusion of the silver ions into the glass matrix, and a two-dimensional reverse diffusion model has been introduced to explain the motion of the silver clusters and their migration toward the glass surface in the presence of the laser beam. The results of the mentioned models were in agreement with our measurements on thickness of the ion-exchange layer by means of optical microscopy and recorded morphology of the glass surface around the laser beam axis by using a Mirau interferometer. SEM micrographs were used to extract the size distribution of the migrated silver particles over the glass surface.

Niry, M. D.; Khalesifard, H. R. [Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Optics Research Center, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Mostafavi-Amjad, J.; Ahangary, A. [Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Azizian-Kalandaragh, Y. [Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Department of Physics, University of Mohaghegh Ardabili (UMA), P.O. Box 179, Ardabil (Iran, Islamic Republic of)

2012-02-01T23:59:59.000Z

144

Specific features of microheterogeneous plasma produced by irradiation of a polymer aerogel target with an intense 500-ps-long laser pulse  

SciTech Connect (OSTI)

The properties of microheterogeneous plasma produced by irradiation of a polymer aerogel target with an intense (10{sup 14} W/cm{sup 3}) short (0.5 ps) 1.064-?m laser pulse were studied. It is found that, even at plasma densities exceeding the critical density, a small fraction of the incident laser radiation penetrates through the plasma in which the processes of density and temperature equalization still take place. The intensification (as compared to plasmas produced from denser foams and solid films) of transport processes in such plasma along and across the laser beam can be caused by the initial microheterogeneity of the solid target. The replacement of a small (10% by mass) part of the polymer with copper nanoparticles leads to a nearly twofold increase in the intensity of the plasma X-ray emission.

Borisenko, N. G.; Merkul’ev, Yu. A.; Orekhov, A. S., E-mail: orekhov@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Chaurasia, S.; Tripathi, S.; Munda, D. S.; Dhareshwar, L. J. [Bhabha Atomic Research Centre, High-Pressure and Synchrotron Radiation Physics Division (India)] [Bhabha Atomic Research Centre, High-Pressure and Synchrotron Radiation Physics Division (India); Pimenov, V. G.; Sheveleva, E. E. [Russian Academy of Sciences, Zelinksy Institute of Organic Chemistry (Russian Federation)] [Russian Academy of Sciences, Zelinksy Institute of Organic Chemistry (Russian Federation)

2013-08-15T23:59:59.000Z

145

Searching for minicharged particles via birefringence, dichroism and Raman spectroscopy of the vacuum polarized by a high-intensity laser wave  

SciTech Connect (OSTI)

Absorption and dispersion of probe photons in the field of a high-intensity circularly polarized laser wave are investigated. The optical theorem is applied for determining the absorption coefficients in terms of the imaginary part of the vacuum polarization tensor. Compact expressions for the vacuum refraction indices and the photon absorption coefficients are obtained in various asymptotic regimes of interest. The outcomes of this analysis reveal that, far from the region relatively close to the threshold of the two-photon reaction, the birefringence and dichroism of the vacuum are small and, in some cases, strongly suppressed. On the contrary, in a vicinity of the region in which the photo-production of a pair occurs, these optical properties are manifest with lasers of moderate intensities. We take advantage of such a property in the search of minicharged particles by considering high-precision polarimetric experiments. In addition, Raman-like electromagnetic waves resulting from the inelastic part of the vacuum polarization tensor are suggested as an alternative form for finding exclusion limits on these hypothetical charge carriers. The envisaged parameters of upcoming high-intensity laser facilities are used for establishing upper bounds on the minicharged particles. -- Highlights: •Via dichroism and birefringence of the vacuum by a strong laser wave, minicharged particles can be probed. •The discovery potential is the highest in a vicinity of the first pair production threshold. •As alternative observable, Raman scattered waves are put forward.

Villalba-Chávez, S., E-mail: selymv@gmail.com; Müller, C., E-mail: c.mueller@tp1.uni-duesseldorf.de

2013-12-15T23:59:59.000Z

146

Note: Characterization of the plasma parameters of a capillary discharge-produced plasma channel waveguide to guide an intense laser pulse  

SciTech Connect (OSTI)

We demonstrated the production of an optical waveguide in a capillary discharge-produced plasma using a cylindrical capillary. Plasma parameters of its waveguide were characterized by use of both a Nomarski laser interferometer and a hydrogen plasma line spectrum. A space-averaged maximum temperature of 3.3 eV with electron densities of the order of 10{sup 17} cm{sup -3} was observed at a discharge time of 150 ns and a maximum discharge current of 400 A. An ultrashort, intense laser pulse was guided by use of this plasma channel.

Higashiguchi, Takeshi; Yugami, Noboru [Department of Advanced Interdisciplinary Sciences and Center for Optical Research and Education (CORE), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kanagawa, Saitama 332-0012 (Japan); Hikida, Masafumi; Terauchi, Hiromitsu; Bai Jinxiang [Department of Advanced Interdisciplinary Sciences and Center for Optical Research and Education (CORE), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan); Kikuchi, Takashi [Department of Electrical Engineering, Nagaoka University of Technology, Kami-tomiokamachi 1603-1, Nagaoka, Niigata 940-2188 (Japan); Tao Yezheng [Center for Energy Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0438 (United States)

2010-04-15T23:59:59.000Z

147

Natural Sciences 2005/06 Cover: Glimpses of research conducted in the Attosecond Laser Laboratory (research leaders Dr John Tisch and Prof Jon  

E-Print Network [OSTI]

-matter interactions, especially the use of femtosecond laser pulses to generate coherent x-ray pulses of attosecond: Glimpses of research conducted in the Attosecond Laser Laboratory (research leaders Dr John Tisch and Prof Jon Marangos). Work in this lab is focused on ultrafast laser physics and high-intensity laser

148

Lasers Optical Engineering Concentration Science/Math/Engineering Electives  

E-Print Network [OSTI]

Chemistry I 4 CHEM113; CHEM114 F, S CIVE260 Engineering Mechanics ­ Statics 3 MATH160; PH141 or co-reg FLasers Optical Engineering Concentration Science/Math/Engineering Electives Course Number Course; CHEM245 or CHEM341 or CHEM345 F, S, SS BIOM306/ BTEC306 Bioprocess Engineering 4 CHEM107 or CHEM111; PH

Schumacher, Russ

149

Laser Cosmology  

E-Print Network [OSTI]

Recent years have seen tremendous progress in our understanding of the cosmos, which in turn points to even deeper questions to be further addressed. Concurrently the laser technology has undergone dramatic revolutions, providing exciting opportunity for science applications. History has shown that the symbiosis between direct observations and laboratory investigation is instrumental in the progress of astrophysics. We believe that this remains true in cosmology. Current frontier phenomena related to particle astrophysics and cosmology typically involve one or more of the following conditions: (1) extremely high energy events; (2) very high density, high temperature processes; (3) super strong field environments. Laboratory experiments using high intensity lasers can calibrate astrophysical observations, investigate underlying dynamics of astrophysical phenomena, and probe fundamental physics in extreme limits. In this article we give an overview of the exciting prospect of laser cosmology. In particular, we showcase its unique capability of investigating frontier cosmology issues such as cosmic accelerator and quantum gravity.

Pisin Chen

2014-02-24T23:59:59.000Z

150

Diode laser measurements of H[sub 2]O line intensities and self-broadening coefficients in the 1. 4-[mu]m region  

SciTech Connect (OSTI)

Precise knowledge of water vapor radiative properties in the infrared spectrum is needed for many applications. Such applications include atmospheric sounding experiments, radiative sensing of combustion processes, and optical diagnostics for gas-dynamic and aerodynamic studies. Spectrally resolved measurements of pure water vapor absorption spectra have been performed with a tunable diode laser. The laser, a distributed feedback InGaAsP diode, emits in the 1.4-[mu]m region. A total of 12 lines were studied corresponding to rovibrational transitions within the [nu][sub 1] + [nu][sub 3] and 2[nu][sub 1] vibrational bands. A Voigt profile analysis of lineshape is used to infer both intensities and self-collision-broadening coefficients of the water vapor. Good agreements is found between the observed line intensities and those recently measured by Toth. These results are apparently the first published measurements of the broadening coefficient within this spectral range.

Langlois, S.; Birbeck, T.P.; Hanson, R.K. (Stanford Univ., CA (United States). Dept. of Mechanical Engineering)

1994-01-01T23:59:59.000Z

151

High-resolution measurements of the spatial and temporal evolution of megagauss magnetic fields created in intense short-pulse laser-plasma interactions  

SciTech Connect (OSTI)

A pump-probe polarimetric technique is demonstrated, which provides a complete, temporally and spatially resolved mapping of the megagauss magnetic fields generated in intense short-pulse laser-plasma interactions. A normally incident time-delayed probe pulse reflected from its critical surface undergoes a change in its ellipticity according to the magneto-optic Cotton-Mouton effect due to the azimuthal nature of the ambient self-generated megagauss magnetic fields. The temporal resolution of the magnetic field mapping is typically of the order of the pulsewidth, limited by the laser intensity contrast, whereas a spatial resolution of a few ?m is achieved by this optical technique. High-harmonics of the probe can be employed to penetrate deeper into the plasma to even near-solid densities. The spatial and temporal evolution of the megagauss magnetic fields at the target front as well as at the target rear are presented. The ?m-scale resolution of the magnetic field mapping provides valuable information on the filamentary instabilities at the target front, whereas probing the target rear mirrors the highly complex fast electron transport in intense laser-plasma interactions.

Chatterjee, Gourab, E-mail: gourab@tifr.res.in; Singh, Prashant Kumar; Adak, Amitava; Lad, Amit D.; Kumar, G. Ravindra, E-mail: grk@tifr.res.in [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)

2014-01-15T23:59:59.000Z

152

Spectroscopic investigations of hard x-ray emission from 120 ps laser-produced plasmas at intensities near 10{sup 17} W cm{sup {minus}2}  

SciTech Connect (OSTI)

Spectroscopic investigations of the x-ray emission of plasmas heated by 120 ps, frequency doubled pulses from the JANUS Nd: glass laser are presented. High Z K-shell spectra emitted from slab targets heated to near 10{sup 17} W cm{sup {minus}2} intensity are investigated. High resolution ({gamma}/{Delta}{gamma}>5000) x-ray spectra of multicharged ions of H-like Ti, Co, Ni, Cu, and also H-like Sc in the spectral range 1.5--3.0 {angstrom} are obtained in single laser shots using a spherically bent Mica crystal spectrograph with a 186 mm radius of curvature. The spectra- have one dimensional spatial resolution of about 25{mu}m and indicate that the size of the emission zone of the resonance, transitions is <25{mu}m. Simultaneous x-ray images of the plasma from a charge-coupled device pinhole camera confirmed that the plasma x-ray emission is from a similar sized source. Survey spectra {gamma}/{Delta}{gamma}=500--1000) taken with a flat LiF (200) crystal spectrometer with a charge-coupled device detector complement the high resolution data. Two dimensional LASNEX modeling of the laser target conditions indicate that the high K-shell charge states are produced in the hot dense region of the plasma with electron temperature >2 keV and density{approximately}10{sup 22} cm{sup {minus}3}. These experiments demonstrate that with modest laser energy, plasmas heated by high-intensity 120 ps lasers provide a very bright source of hard {approximately}8 keV x-ray emission.

Dunn, J.; Young, B.K.F.; Osterheld, A.L.; Foord, M.E.; Walling, R.S.; Stewart, R.E. [Lawrence Livermore National Lab., CA (United States); Faenov, A.Y. [VINIFTRI, Mendeleevo, Moscow Region (Russian Federation)

1995-11-01T23:59:59.000Z

153

Origin of protons accelerated by an intense laser and the dependence of their energy on the plasma density  

Science Journals Connector (OSTI)

We study the high-energy (1–4 MeV) proton production from a slab plasma irradiated by a ultrashort high-power laser. In our 2.5-dimensional particle-in-cell simulations, a p-polarized laser beam of 1.6×1019 W/cm2, 300 fs, ?L=1.053 ?m, illuminates a slab plasma normally; the slab plasma consists of a hydrogen plasma, and the target plasma thickness and the laser spot size are 2.5?L and 5?L, respectively. The simulation results show that an emitted proton energy depends on the slab plasma density, and three kinds of high-energy proton beams are generated at the target plasma surfaces: one kind of the proton beams is produced at the laser-illuminated target surface and accelerated to the same laser-incident side. The second is generated at the target surface opposite to the laser-illuminated target surface and is accelerated outward on the same side. The third is generated at the laser-illuminated target surface and accelerated to the opposite side while passing through the target plasma. The simulations also show a mechanism of proton accelerations. In an overdense plasma, laser energy goes to energies of hot electrons and magnetic fields in part; the electrons oscillate around the slab plasma so that a static electric field is generated and consequently protons are extracted. The magnetic field generated in the slab plasma exists longer and heats up the plasma electrons to sustain the static electric field even after the laser termination.

Takashi Nakamura and Shigeo Kawata

2003-02-06T23:59:59.000Z

154

Comment on 'Dynamics of an electron driven by relativistically intense laser radiation' [Phys. Plasmas 15, 023104 (2008)  

SciTech Connect (OSTI)

Galkin et al. [Phys. Plasmas 15, 023104 (2008)] presented the comparison of the electron dynamics in the cases of the linear and circular polarizations of the optical fields. They assume that the longitudinal component of the laser field can be neglected in the case of longitudinal displacement less than the Rayleigh range. In this comment, we point out that the longitudinal component must be considered for the minimum spot size less than 10 times wavelength for linearly polarized laser pulse and for the minimum spot size less than 15 times wavelength for circularly polarized laser pulse.

Tian Youwei; Bao Gang; Zheng Ying; Yang Jianping [College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); Yu Wei; Wang Xin [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

2010-06-15T23:59:59.000Z

155

Data Life Cycle Labs, A New Concept to Support Data-Intensive Science  

E-Print Network [OSTI]

In many sciences the increasing amounts of data are reaching the limit of established data handling and processing. With four large research centers of the German Helmholtz association the Large Scale Data Management and Analysis (LSDMA) project supports an initial set of scientific projects, initiatives and instruments to organize and efficiently analyze the increasing amount of data produced in modern science. LSDMA bridges the gap between data production and data analysis using a novel approach by combining specific community support and generic, cross community development. In the Data Life Cycle Labs (DLCL) experts from the data domain work closely with scientific groups of selected research domains in joint R&D where community-specific data life cycles are iteratively optimized, data and meta-data formats are defined and standardized, simple access and use is established as well as data and scientific insights are preserved in long-term and open accessible archives.

van Wezel, Jos; Jung, Christopher; Stotzka, Rainer; Halstenberg, Silke; Rigoll, Fabian; Garcia, Ariel; Heiss, Andreas; Schwarz, Kilian; Gasthuber, Martin; Giesler, André

2012-01-01T23:59:59.000Z

156

Fundamental science investigations to develop a 6-MV laser triggered gas switch for ZR: first annual report.  

SciTech Connect (OSTI)

In October 2005, an intensive three-year Laser Triggered Gas Switch (LTGS) development program was initiated to investigate and solve observed performance and reliability issues with the LTGS for ZR. The approach taken has been one of mission-focused research: to revisit and reassess the design, to establish a fundamental understanding of LTGS operation and failure modes, and to test evolving operational hypotheses. This effort is aimed toward deploying an initial switch for ZR in 2007, on supporting rolling upgrades to ZR as the technology can be developed, and to prepare with scientific understanding for the even higher voltage switches anticipated needed for future high-yield accelerators. The ZR LTGS was identified as a potential area of concern quite early, but since initial assessments performed on a simplified Switch Test Bed (STB) at 5 MV showed 300-shot lifetimes on multiple switch builds, this component was judged acceptable. When the Z{sub 20} engineering module was brought online in October 2003 frequent flashovers of the plastic switch envelope were observed at the increased stresses required to compensate for the programmatically increased ZR load inductance. As of October 2006, there have been 1423 Z{sub 20} shots assessing a variety of LTGS designs. Numerous incremental and fundamental switch design modifications have been investigated. As we continue to investigate the LTGS, the basic science of plastic surface tracking, laser triggering, cascade breakdown, and optics degradation remain high-priority mission-focused research topics. Significant progress has been made and, while the switch does not yet achieve design requirements, we are on the path to develop successively better switches for rolling upgrade improvements to ZR. This report summarizes the work performed in FY 2006 by the large team. A high-level summary is followed by detailed individual topical reports.

Warne, Larry Kevin; Van Den Avyle, James A.; Lehr, Jane Marie; Rose, David (Voss Scientific, Albuquerque, NM); Krompholz, Hermann G. (Texas Tech University, Lubbock, TX); Vela, Russell (Texas Tech University, Lubbock, TX); Jorgenson, Roy Eberhardt; Timoshkin, Igor (University of Strathclyde, Glasgow, Scotland); Woodworth, Joseph Ray; Prestwich, Kenneth Randel (Voss Scientific, Albuquerque, NM); Krile, John (Texas Tech University, Lubbock, TX); Given, Martin (University of Strathclyde, Glasgow, Scotland); McKee, G. Randall; Rosenthal, Stephen Edgar; Struve, Kenneth William; Welch, Dale Robert (Voss Scientific, Albuquerque, NM); Benwell, Andrew L. (University of Missouri-Columbia, Columbia, Missouri); Kovaleski, Scott (University of Missouri-Columbia, Columbia, Missouri); LeChien, Keith, R.; Johnson, David (Titan Pulse Sciences Division); Fouracre, R.A. (University of Strathclyde, Glasgow, Scotland); Yeckel, Chris (University of Missouri-Columbia, Columbia, Missouri); Wakeland, Peter Eric (Ktech Corporation, Albuquerque, NM); Miller, A. R. (Titan Pulse Sciences Division); Hodge, Keith Conquest (Ktech Corporation, Albuquerque, NM); Pasik, Michael Francis; Savage, Mark Edward; Maenchen, John Eric; Curry, Randy D. (University of Missouri-Columbia, Columbia, Missouri); Feltz, Greg (Ktech Corporation, Albuquerque, NM); Bliss, David Emery; MacGregor, Scott (University of Strathclyde, Glasgow, Scotland); Corley, J. P. (Ktech Corporation, Albuquerque, NM); Anaya, Victor (Ktech Corporation, Albuquerque, NM); Wallace, Zachariah (Ktech Corporation, Albuquerque, NM); Thoma, Carsten (Voss Scientific, Albuquerque, NM); Neuber, Andreas. (Texas Tech University, Lubbock, TX)

2007-03-01T23:59:59.000Z

157

Generation of quasi-monochromatic beams of accelerated electrons during interaction of weak-contrast intense femtosecond laser radiation with a metal-foil edge  

SciTech Connect (OSTI)

The formation of monoenergetic beams of accelerated electrons by focusing femtosecond laser radiation with an intensity of 2 Multiplication-Sign 10{sup 17} W cm{sup -2} onto an edge of aluminium foil has been experimentally demonstrated. The electrons had energy distributions peaking in the range from 0.2 to 0.8 MeV and an energy spread less than 20 %. The acceleration mechanism related to the generation of a plasma wave as a result of self-modulation instability of the laser pulse in the subcritical plasma formed the prepulse of the laser system (arriving 10 ns before the main pulse) is considered. Onedimensional PIC simulation of the interaction between the laser radiation and plasma with a concentration of 5 Multiplication-Sign 10{sup 19} cm{sup -3} showed that effective excitation of a plasma wave, as well as the trapping and acceleration of the electron beam with an energy on the order of 1 MeV, may occur in the presence of inhomogeneities in the density at the plasma boundary and in the temporal shape of the beam. (extreme light fields and their applications)

Malkov, Yu A; Stepanov, A N; Yashunin, D A; Pugachev, L P; Levashov, P R; Andreev, N E; Andreev, Aleksandr A

2013-03-31T23:59:59.000Z

158

Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile  

SciTech Connect (OSTI)

The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

Habibi, M., E-mail: habibi.physics@gmail.com [Young Researchers and Elite Club, Shirvan Branch, Islamic Azad University, Shirvan (Iran, Islamic Republic of); Ghamari, F. [Young Researchers and Elite Club, Khorramabad Branch, Islamic Azad University, Khorramabad (Iran, Islamic Republic of)

2014-05-15T23:59:59.000Z

159

Electronic and structural response of InSb to ultra-short and ultra-intense laser pulses  

E-Print Network [OSTI]

intensity of Ac 2. 00 gauss. cm. lrn(&(l'1)) for lnSb for a field intensity of A&i ? 2. 23 gauss cm. Im(e(E)) for InSb for a field intensity of A&i -- 2. 40 gauss cm. hn(e(E)) for InSb for a field intensity of A&i 2. 82 gauss cm. Im(&(E)) for InSb for a...-correlation function for InSb for a field intcnsit, y of Ac ? 2. 00 gauss cin. 21 Tiiiic. cvoluti&m of thc pair-correlation function for lnSb for a field intensity of As = 2. 46 gauss cm. 44 Time evolution of the pair-correlation function for InSb for a field...

Burzo, Andrea Mihaela

2001-01-01T23:59:59.000Z

160

Resonance laser-plasma excitation of coherent terahertz phonons in the bulk of fluorine-bearing crystals under high-intensity femtosecond laser irradiation  

SciTech Connect (OSTI)

The dynamics of coherent phonons in fluorine-containing crystals was investigated by pump-probe technique in the plasma production regime. Several phonon modes, whose frequencies are overtones of the 0.38-THz fundamental frequency, were simultaneously observed in a lithium fluoride crystal. Phonons with frequencies of 1 and 0.1 THz were discovered in a calcium fluoride crystal and coherent phonons with frequencies of 1 THz and 67 GHz were observed in a barium fluoride crystal. Furthermore, in the latter case the amplitudes of phonon mode oscillations were found to significantly increase 15 ps after laser irradiation. (interaction of laser radiation with matter)

Potemkin, F V; Mareev, E I [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation); Khodakovskii, N G [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Mikheev, P M

2013-08-31T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Learn More about Fusion & Lasers  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

& Lasers How Lasers Work Learn how lasers were developed and how they work. Outreach NIF & Photon Science researchers take learning opportunities on the road. Glossary Don't...

162

Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy Science: A Talk from Leo Holberg and Allen Mills  

ScienceCinema (OSTI)

Leo Holberg and Allen Mills present a talk at Frontiers in Laser Cooling, Single-Molecule Biophysics and Energy Science, a scientific symposium honoring Steve Chu, director of Lawrence Berkeley National Laboratory and recipient of the 1997 Nobel Prize in Physics. The symposium was held August 30, 2008 in Berkeley.

Holberg, Leo; Mills, Allen [NIST

2011-04-28T23:59:59.000Z

163

Progress towards materials science above 1000 GPa (10 Mbar) on the NIF laser  

SciTech Connect (OSTI)

Solid state dynamics experiments at extreme pressures, P > 1000 GPa (10 Mbar), and ultrahigh strain rates (1.e6-1.e8 1/s) are being developed for the National Ignition Facility (NIF) laser. These experiments will open up exploration of new regimes of materials science at an order of magnitude higher pressures than have been possible to date. Such extreme, solid state conditions can be accessed with a ramped pressure drive. The experimental, computational, and theoretical techniques are being developed and tested on the Omega laser. Velocity interferometer measurements (VISAR) establish the high pressure conditions generated by the ramped drive. Constitutive models for solid state strength under these conditions are tested by comparing simulations with experiments measuring perturbation growth from the Rayleigh-Taylor instability in solid state samples of vanadium. Radiography techniques using synchronized bursts of x-rays have been developed to diagnose this perturbation growth. Experiments on Omega demonstrating these techniques at peak pressures of {approx}1 Mbar will be discussed. The time resolved observation of foil cracking and void formation show the need for tamped samples and a planar drive.

Remington, B A; Park, H; Prisbrey, S T; Pollaine, S M; Cavallo, R M; Rudd, R E; Lorenz, K T; Becker, R; Bernier, J; Barton, N; Arsenlis, T; Glendinning, S G; Hamza, A; Swift, D; Jankowski, A; Meyers, M A

2009-03-12T23:59:59.000Z

164

First Use of High-Frequency Intensity Modulation of Narrow-Linewidth Laser Light and Its Application in Determination of Fr206,205,204 Ground-State Properties  

Science Journals Connector (OSTI)

Collinear laser spectroscopy was performed on the nuclear ground states of the neutron-deficient isotopes Fr206,205,204. A new technique was developed to suppress hyperfine pumping in collinear laser spectroscopy of atoms. This involved high-frequency intensity modulation of narrow-linewidth laser light using fast-switching electro-optical modulators. The nuclear ground-state spins of Fr206,205,204 were determined to be 3, 9/2, and 3, respectively. Both the changes in mean-squared charge radii and nuclear magnetic dipole moments indicate a departure from single-particle estimates.

Annika Voss; Matthew R. Pearson; Jonathan Billowes; Fritz Buchinger; Bradley Cheal; John E. Crawford; Anna A. Kwiatkowski; C. D. Philip Levy; Olivier Shelbaya

2013-09-16T23:59:59.000Z

165

Characterisation of a MeV Bremsstrahlung x-ray source produced from a high intensity laser for high areal density object radiography  

SciTech Connect (OSTI)

Results of an experiment to characterise a MeV Bremsstrahlung x-ray emission created by a short (<10 ps) pulse, high intensity (1.4 × 10{sup 19} W/cm{sup 2}) laser are presented. X-ray emission is characterized using several diagnostics; nuclear activation measurements, a calibrated hard x-ray spectrometer, and dosimeters. Results from the reconstructed x-ray energy spectra are consistent with numerical simulations using the PIC and Monte Carlo codes between 0.3 and 30 MeV. The intense Bremsstrahlung x-ray source is used to radiograph an image quality indicator (IQI) heavily filtered with thick tungsten absorbers. Observations suggest that internal features of the IQI can be resolved up to an external areal density of 85 g/cm{sup 2}. The x-ray source size, inferred by the radiography of a thick resolution grid, is estimated to be approximately 400 ?m (full width half maximum of the x-ray source Point Spread Function)

Courtois, C.; Compant La Fontaine, A.; Bazzoli, S.; Bourgade, J. L.; Gazave, J.; Lagrange, J. M.; Landoas, O.; Dain, L. Le; Pichoff, N. [CEA, DAM, DIF, F-91297 Arpajon (France)] [CEA, DAM, DIF, F-91297 Arpajon (France); Edwards, R.; Aedy, C. [AWE Plc., Aldermaston, Reading RG7 4PR (United Kingdom)] [AWE Plc., Aldermaston, Reading RG7 4PR (United Kingdom); Mastrosimone, D.; Pien, G.; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

2013-08-15T23:59:59.000Z

166

Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Science newsroomassetsimagesscience-icon.png Science Cutting edge, multidisciplinary national-security science. Health Space Computing Energy Earth Materials Science...

167

ChemCam on MSL 2009: first laser induced breakdown spectrometer for space science  

SciTech Connect (OSTI)

ChemCam is one of the 10 instrument suites on the Mars Science Laboratory, a martian rover being built by Jet Propulsion Laboratory, for the next NASA mission to Mars (MSL 2009). ChemCam is an instrument package consisting of two remote sensing instruments: a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). LIBS provides elemental compositions of rocks and soils, while the RMI places the LIBS analyses in their geomorphologic context. Both instruments rely on an autofocus capability to precisely focus on the chosen target, located at distances from the rover comprised between 1 and 9 m for LIBS, and 2 m and infinity for RMI. ChemCam will help determine which samples, within the vicinity of the MSL rover, are of sufficient interest to use the contact and in-situ instruments for further characterization. It will provide valuable analyses of samples that are inaccessible to contact and in-situ instruments, and of a much larger number of samples than can be done with this kind of instrument. ChemCam also has a capability to provide passive spectroscopy data of rocks and soils on Mars. ChemCam hardware consists of a Mast Unit (MU), provided by France, and a Body Unit (BU) built and tested in the USA. The Flight Model of the MU is assembled, tested and now available in the USA, while the BU is currently being assembled and tested. Both will be connected by the end of year '08 for end-to-end functional and performance tests, before delivery to JPL and assembly on the MSL rover. Launch is scheduled for October 09. After describing the concept of ChemCam, this presentation focuses on its French part, Mast Unit. The results presented show that Mast Unit is able to generate a plasma and collect its light, over the full applicable ranges of distances and temperatures on Mars.

Wiens, Roger C [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

168

Direct laser acceleration of electrons in free-space  

E-Print Network [OSTI]

Compact laser-driven accelerators are versatile and powerful tools of unarguable relevance on societal grounds for the diverse purposes of science, health, security, and technology because they bring enormous practicality to state-of-the-art achievements of conventional radio-frequency accelerators. Current benchmarking laser-based technologies rely on a medium to assist the light-matter interaction, which impose material limitations or strongly inhomogeneous fields. The advent of few cycle ultra-intense radially polarized lasers has materialized an extensively studied novel accelerator that adopts the simplest form of laser acceleration and is unique in requiring no medium to achieve strong longitudinal energy transfer directly from laser to particle. Here we present the first observation of direct longitudinal laser acceleration of non-relativistic electrons that undergo highly-directional multi-GeV/m accelerating gradients. This demonstration opens a new frontier for direct laser-driven particle accelerati...

Carbajo, Sergio; Wong, Liang Jie; Miller, R J Dwayne; Kärtner, Franz X

2015-01-01T23:59:59.000Z

169

Chirped pulse inverse free-electron laser vacuum accelerator  

DOE Patents [OSTI]

A chirped pulse inverse free-electron laser (IFEL) vacuum accelerator for high gradient laser acceleration in vacuum. By the use of an ultrashort (femtosecond), ultrahigh intensity chirped laser pulse both the IFEL interaction bandwidth and accelerating gradient are increased, thus yielding large gains in a compact system. In addition, the IFEL resonance condition can be maintained throughout the interaction region by using a chirped drive laser wave. In addition, diffraction can be alleviated by taking advantage of the laser optical bandwidth with negative dispersion focusing optics to produce a chromatic line focus. The combination of these features results in a compact, efficient vacuum laser accelerator which finds many applications including high energy physics, compact table-top laser accelerator for medical imaging and therapy, material science, and basic physics.

Hartemann, Frederic V. (Dublin, CA); Baldis, Hector A. (Pleasanton, CA); Landahl, Eric C. (Walnut Creek, CA)

2002-01-01T23:59:59.000Z

170

Laser particle sorter  

DOE Patents [OSTI]

Method and apparatus are provided for sorting particles, such as biological particles. A first laser is used to define an optical path having an intensity gradient which is effective to propel the particles along the path but which is sufficiently weak that the particles are not trapped in an axial direction. A probe laser beam is provided for interrogating the particles to identify predetermined phenotypical characteristics of the particles. A second laser beam is provided to intersect the driving first laser beam, wherein the second laser beam is activated by an output signal indicative of a predetermined characteristic. The second laser beam is switchable between a first intensity and a second intensity, where the first intensity is effective to displace selected particles from the driving laser beam and the second intensity is effective to propel selected particles along the deflection laser beam. The selected particles may then be propelled by the deflection beam to a location effective for further analysis. 2 figs.

Martin, J.C.; Buican, T.N.

1987-11-30T23:59:59.000Z

171

Self-interaction-free time-dependent density-functional theory for molecular processes in strong fields:? High-order harmonic generation of H2 in intense laser fields  

E-Print Network [OSTI]

.29 215.30 25 210.20 210.19 49 216.48 216.50 FIG. 2. The induced dipole moment ^ z(t) & and dipole accelera- tion ^ (d2z(t)/dt2)/v02& of H2 at R51.4a0 as a function of time ~in optical cycles!. The laser intensity is 1014 W/cm2 and wavelength 1064 nm...

Chu, Shih-I; Chu, Xi

2001-01-17T23:59:59.000Z

172

Laser-based trace gas detection with applications in biology and medical science  

Science Journals Connector (OSTI)

OPOs and QC-lasers in combination with off-axis ICOS are used to detect trace gases emitted from biological tissue. Ethylene and Nitric oxide emission are detected from plants and HCN...

Harren, Frans J M

173

Science at the Timescale of the Electron: Tabletop X-ray Lasers...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of the Electron: Tabletop X-ray Lasers and Applications in Nanoscience and Nanotechnology November 21, 2014 11:00AM to 12:00PM Presenter Margaret Murnane, University of...

174

Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

GEANIE John Ullman John Ullman A worker checks a laser diagnostic used on the Barolo subcritical experiment. A worker checks a laser diagnostic used on the Barolo subcritical...

175

Science on high-energy lasers: From today to the NIF  

SciTech Connect (OSTI)

This document presents both a concise definition of the current capabilities of high energy lasers and a description of capabilities of the NIF (National Ignition Facility). Five scientific areas are discussed (Astrophysics, Hydrodynamics, Material Properties, Plasma Physics, Radiation Sources, and Radiative Properties). In these five areas we project a picture of the future based on investigations that are being carried on today. Even with this very conservative approach we find that the development of new higher energy lasers will make many extremely exciting areas accessible to us.

Lee, R.W.; Petrasso, R.; Falcone, R.W.

1995-01-01T23:59:59.000Z

176

Correlated-Intensity velocimeter for Arbitrary Reflector  

DOE Patents [OSTI]

A velocimetry apparatus and method comprising splitting incoming reflected laser light and directing the laser light into first and second arms, filtering the laser light with passband filters in the first and second arms, one having a positive passband slope and the other having a negative passband slope, and detecting the filtered laser light via light intensity detectors following the passband filters in the first and second arms

Wang, Zhehui (Los Alamos, NM); Luo, Shengnian (Los Alamos, NM); Barnes, Cris W. (Arlington, VA); Paul, Stephen F. (West Orange, NJ)

2008-11-11T23:59:59.000Z

177

Frontiers in Science Lectures  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

or Neither? The new science of epigenetics Exploring Mars: Curiosity and its laser Higgs Boson and Beyond: The quest for new laws of physics Frontiers in Science Lectures...

178

Laser-driven fusion  

Science Journals Connector (OSTI)

The use of intense laser light to bring about thermonuclear reactions in a plasma is of considerable current interest. We present detailed analytical and computational studies which show the feasibility of laser-driven fusion. The required laser technology and the presently anticipated practical difficulties are discussed in outline.

Keith A. Brueckner and Siebe Jorna

1974-04-01T23:59:59.000Z

179

The Theta Laser A Low Noise Chirped Pulse Laser  

E-Print Network [OSTI]

The Theta Laser A Low Noise Chirped Pulse Laser Dimitrios Mandridis dmandrid@creol.ucf.edu April 29, 2011 CREOL Affiliates Day 2011 #12;2 Objective: Frequency Swept (FM) Mode-locked Laser · Develop a frequency swept laser, · linear f-sweep, · uniform-intensity, · low noise, · with long-term stability

Van Stryland, Eric

180

Observation of multiple ionization pathways for OCS in an intense laser field resolved by three-dimensional covariance mapping and visualized by hierarchical ionization topology  

SciTech Connect (OSTI)

The two- and three-body Coulomb explosion of carbonyl sulfide (OCS) by 790 nm, 50 fs laser pulses focused to {approx_equal}10{sup 16} W cm{sup -2} has been investigated by the three-dimensional covariance mapping technique. In a triatomic molecule, a single charge state, in this case the trication, has been observed to dissociate into two distinct energy channels. With the aid of a three-dimensional visualization technique to reveal the ionization hierarchy, evidence is presented for the existence of two sets of ionization pathways resulting from these two initial states. While one group of ions can be modeled using a classical enhanced ionization model, the second group, consisting of mainly asymmetric channels, cannot. The results provide clear evidence that an enhanced ionization approach must also be accompanied by an appreciation of the effects of excited ionic states and multielectronic processes.

Bryan, W. A.; Newell, W. R.; Sanderson, J. H.; Langley, A. J. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Department of Physics, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom)

2006-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Observation of multiple ionization pathways for OCS in an intense laser field resolved by three-dimensional covariance mapping and visualized by hierarchical ionization topology  

E-Print Network [OSTI]

The two- and three-body Coulomb explosion of carbonyl sulfide (OCS) by 790 nm, 50 fs laser pulses focussed to $\\approx $ 10$^{16}$ Wcm$^{-2}$ has been investigated by three-dimensional covariance mapping technique. For the first time in a triatomic molecule, a single charge state, in this case the trication, has been observed to dissociate into two distinct energy channels. With the aid of a three dimensional visualization technique to reveal the ionization hierarchy, evidence is presented for the existence of two sets of ionization pathways resulting from these two initial states. While one group of ions can be modeled using a Classical enhanced ionization model, the second group, consisting of mainly asymmetric channels, can not. The results provide clear evidence that an enhanced ionization approach must also be accompanied by an appreciation of the effects of excited ionic states and multi-electronic processes.

W. A. Bryan; W. R. Newell; J. H. Sanderson; A. J. Langley

2006-10-10T23:59:59.000Z

182

Laser induced nuclear reactions  

SciTech Connect (OSTI)

Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10{sup 19} W/cm{sup 2}. In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that {mu}Ci of {sup 62}Cu can be generated via the ({gamma},n) reaction by a laser with an intensity of about 10{sup 19} Wcm{sup -2}.

Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin [Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom); European Commission, Institute for Transuranic Elements, Karlsruhe, Postfach 2340, D-76125 (Germany); Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow G75 0QU (United Kingdom); Rutherford Appleton Laboratory, Chilton, Didcot (United Kingdom); Blackett Laboratory, Imperial College, London SW7 2BZ (United Kingdom); Clarendon Laboratory, Department of Physics, University of Oxford, OX1 3PU (United Kingdom)

1998-12-16T23:59:59.000Z

183

Laser Safety Laser-emitting tools and equipment are common to many work situations. Lasers in printers, grocery store  

E-Print Network [OSTI]

Laser Safety Laser-emitting tools and equipment are common to many work situations. Lasers in printers, grocery store scanners, construction tools, and laser pointers are generally lower powered lasers emit high-intensity, directional light beams that vary in strength, they are a particular hazard

Burke, Peter

184

Entropy Driven Atomic Motion in Laser-Excited Bismuth  

SciTech Connect (OSTI)

We introduce a thermodynamical model based on the two-temperature approach in order to fully understand the dynamics of the coherent A{sub 1g} phonon in laser-excited bismuth. Using this model, we simulate the time evolution of (111) Bragg peak intensities measured by Fritz et al.[Science 315, 633 (2007)] in femtosecond x-ray diffraction experiments performed on a bismuth film for different laser fluences. The agreement between theoretical and experimental results is striking not only because we use fluences very close to the experimental ones but also because most of the model parameters are obtained from ab initio calculations performed for different electron temperatures.

Giret, Y.; Gelle, A.; Arnaud, B. [Institut de Physique de Rennes (IPR), UMR UR1-CNRS 6251, Campus de Beaulieu-Bat 11 A, 35042 Rennes Cedex, France, EU (France)

2011-04-15T23:59:59.000Z

185

Earth Sciences Environmental Earth Sciences,  

E-Print Network [OSTI]

84 Earth Sciences­ Environmental Earth Sciences, Geology MGeol (Single Honours Degrees) Earth Sciences BSc (Single Honours Degrees) Environmental Earth Sciences Geology BSc (Joint Honours Degrees) and among the most research-intensive in Europe. Features * The Department of Earth and Environmental

Brierley, Andrew

186

Laser Roadshow  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

outreach Laser Roadshow The NIF Laser Roadshow includes a number of interactive laser demonstrations (Laser Light Fountain, Laser DJ, and NIF "3D ride") that have traveled across...

187

National Ignition Facility & Photon Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

5 National Ignition Facility & Photon Science how do Lasers work? how Do Lasers work? A laser can be as small as a microscopic computer chip or as immense as the National Ignition...

188

Fusion Energy Sciences Network Requirements  

E-Print Network [OSTI]

program to achieve ignition, to provide laser facility timeIgnition Facility National Institute for Fusion Science National LaserIgnition Facility (NIF). In support of the OMEGA Laser

Dart, Eli

2014-01-01T23:59:59.000Z

189

Device Architecture Simplification of Laser Pattering in High-Volume Crystalline Silicon Solar Cell Fabrication using Intensive Computation for Design and Optimization  

SciTech Connect (OSTI)

Prices of Si based solar modules have been continuously declining in recent years. Goodrich is pointing out that a significant portion of these cost reductions have come about due to ?economies of scale? benefits, but there is a point of diminishing returns when trying to lower cost by simply expanding production capacity [1]. Developing innovative high volume production technologies resulting in an increase of conversion efficiency without adding significant production cost will be necessary to continue the projected cost reductions. The Foundational Program to Advance Cell Efficiency (F-PACE) is seeking to achieve this by closing the PV efficiency gap between theoretical achievable maximum conversion efficiency - 29% for c-Si - and the current typical production - 18.5% for a typical full area back contact c-Si Solar cell ? while targeting a module cost of $0.50/Watt . The research conducted by SolarWorldUSA and it?s partners within the FPACE framework focused on the development of a Hybrid metal-wrap-through (MWT) and laser-ablated PERC solar cell design employing a extrusion metallization scheme to achieve >20% efficient devices. The project team was able to simulate, develop and demonstrate the technologies necessary to build p-type MWT PERC cells with extruded front contacts. Conversion efficiencies approaching 20% were demonstrated and a path for further efficiency improvements identified. A detailed cost of ownership calculation for such a device was based on a NREL cost model and is predicting a $/Watt cost below 85 cents on a 180 micron substrate. Several completed or planned publications by SolarWorldUSA and our partners are based on the research conducted within this project and are adding to a better understanding of the involved technologies and materials. Several aspects and technologies of the proposed device have been assessed in regards to technical effectiveness and economic feasibility. It has been shown in a pilot demonstration with wafer thicknesses down to 120 micron that further wafer thickness reduction is only economically viable if handling and contact formation limitations are addressed simultaneously. Furthermore the project partners assessed and demonstrated the feasibility of processing wafers with vias connecting front and back sides through a PERC cell process and aligning and connecting those vias with a non-contact metallization. A close cooperation between industry and institutes of higher education in the Pacific Northwest as shown in this project is of direct benefit to the public and is contributing to the education of the next generation of PV engineers and scientist.

Grupp Mueller, Guenther [SolarWorld; Herfurth, Hans [Fraunhofer CLT; Dunham, Scott [University of Washington; Xu, Baomin [PARC

2013-11-15T23:59:59.000Z

190

Two-gigawatt burst-mode operation of the intense microwave prototype (IMP) free-electron laser (FEL) for the microwave tokamak experiment (MTX)  

SciTech Connect (OSTI)

The MTX explored the plasma heating effects of 140 GHz microwaves from both Gyrotrons and from the IMP FEL wiggler. The Gyrotron was long pulse length (0.5 seconds maximum) and the FEL produced short-pulse length, high-peak power, single and burst modes of 140 GHZ microwaves. Full-power operations of the IMP FEL wiggler were commenced in April of 1992 and continued into October of 1992. The Experimental Test Accelerator H (ETA-II) provided a 50-nanosecond, 6-MeV, 2--3 kAmp electron beam that was introduced co-linear into the IMP FEL with a 140 GHz Gyrotron master oscillator (MO). The FEL was able to amplify the MO signal from approximately 7 kW to peaks consistently in the range of 1--2 GW. This microwave pulse was transmitted into the MTX and allowed the exploration of the linear and non-linear effects of short pulse, intense power in the MTX plasma. Single pulses were used to explore and gain operating experience in the parameter space of the IMP FEL, and finally evaluate transmission and absorption in the MTX. Single-pulse operations were repeatable. After the MTX was shut down burst-mode operations were successful at 2 kHz. This paper will describe the IMP FEL, Microwave Transmission System to MTX, the diagnostics used for calorimetric measurements, and the operations of the entire Microwave system. A discussion of correlated and uncorrelated errors that affect FEL performance will be made Linear and non-linear absorption data of the microwaves in the MTX plasma will be presented.

Felker, B.; Allen, S.; Bell, H. [and others

1993-10-06T23:59:59.000Z

191

Science  

Science Journals Connector (OSTI)

As a self-confessed purveyor of ``frequently outrageous views,'' Steve Fuller can be relied on for a spirited and provocative text - and so this proves. Jerry Ravetz's gushing endorsement on the back cover claims that the public's understanding of science ``will never be the same again'' and that the book proves Steve Fuller to be ``actually science's best friend.'' But those of an orthodox scientific persuasion (though perhaps not his intended audience) are likely to be provoked into dyspeptic displeasure by the first few sideswipes at what they hold most dear. This short text comprises one volume of the series `` Concepts in Social Science,'' in publishing order sandwiched between Rights and Liberalism. Its expressed aim is that the reader come away thinking ``that the idea and institution of `science' go to the very heart of what the social sciences are about.'' In a style that is always inspired but for all save the cognoscenti can sometimes verge on the abstruse, Fuller argues that social and scientific realities are inextricably intertwined. Science's implausible knowledge claims of detachment and objectivity succeed only in perpetuating self-delusion, sowing the seeds for science's own demise. For those familiar with the sociology of scientific knowledge (SSK) debates, the overall message will not be entirely new - and indeed the book is in part a reworking of some of Fuller's previously-published journal articles - but the liveliness of this contentious prose and its immodest, sweeping polemical style present a critical case against science that is often uncomfortably near the bone. What is impressive is Fuller's intellectual boldness in weaving together a wealth of sociological, philosophical and historical arguments that aim to reveal for public scrutiny the true nature of science. The picture of science created is of its frailty and everydayness - qualities that Fuller claims have been disguised by an unattractive mix of intellectual cunning and social naiveté from scientists. Fuller portrays a lay public that combines insight and innocence. Sometimes the public can see through science's ploys for extravagant research proposals, thereby ``displaying a fundamentally sound instinctive response to science.'' At other times, the public is foolish enough to regard scientific knowledge as distinct and authoritative - ``reliable'' lay beliefs about science he says are sadly rare. Thus, in Fuller's eyes, misunderstandings of science abound. Whereas some critics see the yearly panjandrum that constitutes Science Weeks as a clumsy and politically naive stab at ``public relations,'' Fuller sees darker forces of ignorance at work - ``evidence of the scientific community misunderstanding something significant about the social conditions that enable its existence.'' Tackling the public understanding of science (PUS) debate in such a spirit in Chapter 1 sets the tone for the protracted dissection of science that follows. But Fuller's aim is more to do with the revelation of sociological phenomena than with ridicule of science. For example, in Chapter 2 the idiosyncrasies of particular scientific disciplines are picked apart (in the best sociological tradition, physics comes in for a good deal of epistemological stick). Fuller succeeds in portraying the various branches of science as fundamentally different, with distinct working practices shaped by different histories and presumptions. Why, the author then muses, are interdisciplinary wars within science rare, in contrast to social science? With such questions to crack, science is rich pickings for sociological inquiry. In Chapter 3, Fuller's concern is the many-layered meanings of the terms science, scientific and scientists. Here the author takes us through the sociological and philosophical twists and turns of meaning with ideological ease, neatly contrasting today's science with that of the past. For example, long gone is science's unquestioned claim always to serve the best interest of the state; now science is self-serving. Much missed too is science's ability to stab

Jeff Thomas, Centre for Science Education, The Open

1998-01-01T23:59:59.000Z

192

X-ray laser  

DOE Patents [OSTI]

An X-ray laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper X-ray laser state by line emission from hydrogen-like silicon ions (32). The novel X-ray laser should prove especially useful for the microscopy of biological specimens.

Nilsen, Joseph (Livermore, CA)

1991-01-01T23:59:59.000Z

193

SCIENCE  

Science Journals Connector (OSTI)

SCIENCE ... Sedoheptulose phosphate may be an important intermediate in carbohydrate metabolism in animals as well as in plants, the NIH scientists observe. ... NOL Makes Magnetic Material ...

1952-06-23T23:59:59.000Z

194

Laser Facilities, Laser-Plasmas & Diagnostics Plasmas Division  

E-Print Network [OSTI]

of freely moving ions and free electrons. Figure 1: The large NOVA laser at Lawrence Livermore National Facility (NIF) is the world's largest and highest-energy laser (Figure 2). It houses 192 intense laser and of a single wavelength. There are a large number of Figure 2: NIF from above & the target chamber. Figure 4

Strathclyde, University of

195

Explosively pumped laser light  

DOE Patents [OSTI]

A single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

Piltch, Martin S. (Los Alamos, NM); Michelotti, Roy A. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

196

Laser acceleration of ion beams  

E-Print Network [OSTI]

We consider methods of charged particle acceleration by means of high-intensity lasers. As an application we discuss a laser booster for heavy ion beams provided, e.g. by the Dubna nuclotron. Simple estimates show that a cascade of crossed laser beams would be necessary to provide additional acceleration to gold ions of the order of GeV/nucleon.

I. A. Egorova; A. V. Filatov; A. V. Prozorkevich; S. A. Smolyansky; D. B. Blaschke; M. Chubaryan

2007-02-01T23:59:59.000Z

197

2011 Intensity -1 INTENSITY OF SOUND  

E-Print Network [OSTI]

the rate at which energy is passing a certain point. This concept involves sound intensity. Consider the sound intensity. Recall the time rate of energy transfer is called "power". Thus, sound intensity2011 Intensity - 1 INTENSITY OF SOUND The objectives of this experiment are: · To understand

Glashausser, Charles

198

Final Report for DE-SC0002298 Agency Number: DE-PS02-09ER09-01 An Advanced Network and distributed Storage Laboratory (ANDSL) for Data Intensive Science  

SciTech Connect (OSTI)

The original intent of this project was to build and operate an Advanced Network and Distributed Storage Laboratory (ANDSL) for Data Intensive Science that will prepare the Open Science Grid (OSG) community for a new generation of wide area communication capabilities operating at a 100Gb rate. Given the significant cut in our proposed budget we changed the scope of the ANDSL to focus on the software aspects of the laboratory – workload generators and monitoring tools and on the offering of experimental data to the ANI project. The main contributions of our work are twofold: early end-user input and experimental data to the ANI project and software tools for conducting large scale end-to-end data placement experiments.

Livny, Miron [Computer Sciences Department, University of Wisconsin - Madison

2014-08-17T23:59:59.000Z

199

Injection locked oscillator system for pulsed metal vapor lasers  

DOE Patents [OSTI]

An injection locked oscillator system for pulsed metal vapor lasers is disclosed. The invention includes the combination of a seeding oscillator with an injection locked oscillator (ILO) for improving the quality, particularly the intensity, of an output laser beam pulse. The present invention includes means for matching the first seeder laser pulses from the seeding oscillator to second laser pulses of a metal vapor laser to improve the quality, and particularly the intensity, of the output laser beam pulse.

Warner, Bruce E. (Livermore, CA); Ault, Earl R. (Dublin, CA)

1988-01-01T23:59:59.000Z

200

SCIENCE  

Science Journals Connector (OSTI)

SCIENCE ... Neutral V-particles were first discovered in 1947 at the University of Manchester where researchers observed v-shaped tracks in a magnetic cloud chamber exposed to cosmic rays. ...

1953-08-17T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Laser Ignition  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Ignition Laser Ignition A first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable...

202

Optics & Laser Technology, Vol. 29, No. 1, pp. 35-39, 1997 Copyright 0 1996 Elsevier Science Ltd  

E-Print Network [OSTI]

a single xenon flashlamp as the light source. Cross-calibration against single-parameter commercial tank at sea. Copyright @ 1996 Elsevier Science Ltd. KEYWORDS: marine monitoring, submersible

Strathclyde, University of

203

Molecular dynamics in intense laser fields  

Science Journals Connector (OSTI)

...simpleman's model for above threshold ionization (ATI), where excess photons are absorbed on top of the minimum amount required...process for heavy molecules. Fragment atoms such as hydrogen and lithium, and their isotopes, are more difficult to study in this...

1999-01-01T23:59:59.000Z

204

Effect of pulse intensity distributions on fragment internal energy in the infrared multiphoton dissociation of vinyl  

E-Print Network [OSTI]

Effect of pulse intensity distributions on fragment internal energy in the infrared multiphoton of laser intensity on the production of fragment energy distribu- tions. Laser induced fluorescence (LIF pumping is pro- portional to the light intensity, the final energy of the parent molecule

Zare, Richard N.

205

Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

149802 149802 , 1291 (2007); 318 Science et al. L. Ozyuzer, Superconductors Emission of Coherent THz Radiation from www.sciencemag.org (this information is current as of November 29, 2007 ): The following resources related to this article are available online at http://www.sciencemag.org/cgi/content/full/318/5854/1291 version of this article at: including high-resolution figures, can be found in the online Updated information and services, http://www.sciencemag.org/cgi/content/full/318/5854/1291/DC1 can be found at: Supporting Online Material found at: can be related to this article A list of selected additional articles on the Science Web sites http://www.sciencemag.org/cgi/content/full/318/5854/1291#related-content http://www.sciencemag.org/cgi/content/full/318/5854/1291#otherarticles

206

SCience  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

all all SCience Chicago Office Environment, Safety and Health Functions, Responsibilities, and Authorities Manual December 2012 ~5 {?JI-- l L-H1- I Roxanne E. Purucker, Manager Date SC-CH FRAM Revision 7 Office of Science - Chicago Office SC-CH Revision History TITLE: SC-CH Functions, Responsibilities, and Authorities Manual POINT OF CONTACT: Karl Moro SCMS MANAGEMENT SYSTEM: Environment, Safety and Health (ES&H) TO BE UPDATED: December 31, 2013 Revision Date Reason/Driver Description 5 Oct 10 Annual review and revision of the SC-CH ES&H Functions, Responsibilities, and Authorities Manual Changes were primarily made to address administrative and organizational changes and general improvement of text and presentation. I 6 Nov 11 Annual review and revision of

207

Effects of powder feeding rate on interaction between laser beam and powder streamin laser cladding process  

Science Journals Connector (OSTI)

A theoretical model was presented to calculate the laser intensity distribution and the particle temperatures at different sites of the workpiece in the laser cladding process. By using this model, the ... effect...

Huang Yan-lu; Li Jian-guo; Liang Gong-ying…

2004-12-01T23:59:59.000Z

208

The rapid progress of nanoscale science and technology challenges the optoelectronics community to develop ever smaller lasers and other optoelectronic devices compatible with  

E-Print Network [OSTI]

The miniaturization of optoelectronic devices such as light emitting diodes or semiconduc- tor lasers, is expected

Wu, Shin-Tson

209

Microsoft Word - Defense Science Quarterly 03-09.doc  

National Nuclear Security Administration (NNSA)

March 2009 March 2009 Defense Science Quarterly Inside This Issue 1 Message from the Director 2 Carnegie-DOE Alliance Center 3 Cornell Center for the Study of Pulsed Power Driven High Energy Density Plasmas 4 Center of Excellence for Radioactive Ion Beam Studies for Stewardship Science 5 The Texas Center for High Intensity Laser Science 6 The Institute for Shock Physics, Washington State University 7 The High Pressure Science and Engineering Center at the University of Nevada, Las Vegas 8 HEDP Research at the Nevada Terawatt Facility 9 Publication Highlights and Awards and Highlights Message from the Director Chris Deeney, Defense Science Division This quarterly newsletter was very therapeutic. We are embroiled in so much budget action that taking the time

210

Techniques for optically compressing light intensity ranges  

DOE Patents [OSTI]

A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten uranium in an atomic vapor laser isotope separator (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. A number of different means for compressing the intensity range are disclosed. These include the use of photogray glass, the use of a pair of interference filters, and the utilization of a new liquid crystal notch filter in combination with an interference filter.

Rushford, Michael C. (Livermore, CA)

1989-01-01T23:59:59.000Z

211

Techniques for optically compressing light intensity ranges  

DOE Patents [OSTI]

A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten uranium in an atomic vapor laser isotope separator (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. A number of different means for compressing the intensity range are disclosed. These include the use of photogray glass, the use of a pair of interference filters, and the utilization of a new liquid crystal notch filter in combination with an interference filter. 18 figs.

Rushford, M.C.

1989-03-28T23:59:59.000Z

212

Vibration intensity difference thresholds.  

E-Print Network [OSTI]

??The intensity difference threshold is defined as ‘the difference in the intensity of two stimuli which is just sufficient for their difference to be detected’.… (more)

Forta, Nazim Gizem

2009-01-01T23:59:59.000Z

213

Laser Cladding  

Science Journals Connector (OSTI)

Laser cladding is a surface modification process in which a laser beam is used to melt an addition ... process must be clearly differentiated from that of laser surface alloying ( Laser Surface Al...

Prof. Dr. José L. Ocańa; Prof. Janez Grum

2013-01-01T23:59:59.000Z

214

Fast Ignition: Nuclear Fusion with UltraFast Ignition: Nuclear Fusion with Ultra--intenseintense LASERsLASERs  

E-Print Network [OSTI]

pellet composed of deuterium and tritium. In the fast ignition regime a secondy p g g p p g g laser, nearly limitless, fuel source. Fusion via Fast Ignition MethodUltra-Intense Laser Research atFusion via Direct Drive Method U Strathclyde IgnitionCompression IgnitionCompression · Very intense lasers (shown

Strathclyde, University of

215

Fundamental physics on natures of the macroscopic vacuum under high intense electromagnetic fields with accelerators  

E-Print Network [OSTI]

High intense electromagnetic fields can be unique probes to study natures of macroscopic vacua by themselves. Combining accelerators with the intense field can provide more fruitful probes which can neither be achieved by only intense fields nor only high energy accelerators. We will overview the natures of vacua which can be accessible via intense laser-laser and intense laser-electron interactions. In the case of the laser-laser interaction, we propose how to observe nonlinear QED effects and effects of new fields like light scalar and pseudo scalar fields which may contribute to a macroscopic nature of our universe such as dark energy. In the case of the laser-electron interaction, in addition to nonlinear QED effects, we can further discuss the nature of accelerating field in the vacuum where we can access physics related with event horizons such as Hawking-Unruh radiations. We will introduce a recent experimental trial to search for this kind of odd radiations.

Kensuke Homma

2009-11-30T23:59:59.000Z

216

Laser cooling of solids  

SciTech Connect (OSTI)

We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

Epstein, Richard I [Los Alamos National Laboratory; Sheik-bahae, Mansoor [UNM

2008-01-01T23:59:59.000Z

217

Laser Noise Reduction in Air  

E-Print Network [OSTI]

Fluctuations of the white-light supercontinuum produced by ultrashort laser pulses in selfguided filaments (spatio-temporal solitons) in air are investigated. We demonstrate that correlations exist within the white-light supercontinuum, and that they can be used to significantly reduce the laser intensity noise by filtering the spectrum. More precisely, the fundamental wavelength is anticorrelated with the wings of the continuum, while conjugated wavelength pairs on both sides of the continuum are strongly correlated. Spectral filtering of the continuum reduces the laser intensity noise by 1.2 dB, showing that fluctuations are rejected to the edges of the spectrum.

Pierre Bejot; Jerome Kasparian; Estelle Salmon; Roland Ackermann; Nicolas Gisin; Jean-Pierre Wolf

2006-08-09T23:59:59.000Z

218

Quantitative laser-induced breakdown spectroscopy data using peak area step-wise regression analysis: an alternative method for interpretation of Mars science laboratory results  

SciTech Connect (OSTI)

The ChemCam instrument on the Mars Science Laboratory (MSL) will include a laser-induced breakdown spectrometer (LIBS) to quantify major and minor elemental compositions. The traditional analytical chemistry approach to calibration curves for these data regresses a single diagnostic peak area against concentration for each element. This approach contrasts with a new multivariate method in which elemental concentrations are predicted by step-wise multiple regression analysis based on areas of a specific set of diagnostic peaks for each element. The method is tested on LIBS data from igneous and metamorphosed rocks. Between 4 and 13 partial regression coefficients are needed to describe each elemental abundance accurately (i.e., with a regression line of R{sup 2} > 0.9995 for the relationship between predicted and measured elemental concentration) for all major and minor elements studied. Validation plots suggest that the method is limited at present by the small data set, and will work best for prediction of concentration when a wide variety of compositions and rock types has been analyzed.

Clegg, Samuel M [Los Alamos National Laboratory; Barefield, James E [Los Alamos National Laboratory; Wiens, Roger C [Los Alamos National Laboratory; Dyar, Melinda D [MT HOLYOKE COLLEGE; Schafer, Martha W [LSU; Tucker, Jonathan M [MT HOLYOKE COLLEGE

2008-01-01T23:59:59.000Z

219

Dye laser amplifier  

DOE Patents [OSTI]

An improved dye laser amplifier is disclosed. The efficiency of the dye lr amplifier is increased significantly by increasing the power of a dye beam as it passes from an input window to an output window within the dye chamber, while maintaining the intensity of the dye beam constant.

Moses, Edward I. (Livermore, CA)

1992-01-01T23:59:59.000Z

220

Collaborative Research: Instability and transport of laser beam in plasma  

SciTech Connect (OSTI)

Our goal was to determine the onset of laser light scattering due to plasma wave instabilities. Such scatter is usually regarded as deleterious since laser beam strength is thereby diminished. While this kind of laser-plasma-instability (LPI) has long been understood for the case of coherent laser light, the theory of LPI onset for a laser beam with degraded coherence is recent. Such a laser beam fills plasma with a mottled intensity distribution, which has large fluctuations. The key question is: do the exceptionally large fluctuations control LPI onset or is it controlled by the relatively quiescent background laser intensity? We have answered this question. This is significant because LPI onset power in the former case is typically small compared to that of the latter. In addition, if large laser intensity fluctuations control LPI onset, then nonlinear effects become significant for less powerful laser beams than otherwise estimated.

Rose, Harvey Arnold [New Mexico Consortium; Lushnikov, Pavel [University of New Mexico

2014-11-18T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Short rise time intense electron beam generator  

DOE Patents [OSTI]

A generator for producing an intense relativisitc electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.

Olson, C.L.

1984-03-16T23:59:59.000Z

222

Image synthesis from nonimaged laser-speckle patterns  

Science Journals Connector (OSTI)

We demonstrate that unspeckled images of coherently illuminated, diffuse objects can be formed from measurements of backscattered laser-speckle intensity. The theoretical basis for...

Idell, Paul S; Fienup, J R; Goodman, Ron S

1987-01-01T23:59:59.000Z

223

Laser Ignition  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Ignition Laser Ignition Laser Ignition A first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Available for thumbnail of Feynman Center (505) 665-9090 Email Laser Ignition A first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In two embodiments the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion

224

Fiber laser coupled optical spark delivery system  

DOE Patents [OSTI]

A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

Yalin, Azer (Fort Collins, CO); Willson, Bryan (Fort Collins, CO); Defoort, Morgan (Fort Collins, CO); Joshi, Sachin (Fort Collins, CO); Reynolds, Adam (Fort Collins, CO)

2008-03-04T23:59:59.000Z

225

Guest Editorial: Laser Damage  

SciTech Connect (OSTI)

Laser damage of optical materials, first reported in 1964, continues to limit the output energy and power of pulsed and continuous-wave laser systems. In spite of some 48 years of research in this area, interest from the international laser community to laser damage issues remains at a very high level and does not show any sign of decreasing. Moreover, it grows with the development of novel laser systems, for example, ultrafast and short-wavelength lasers that involve new damage effects and specific mechanisms not studied before. This interest is evident from the high level of attendance and presentations at the annual SPIE Laser Damage Symposium (aka, Boulder Damage Symposium) that has been held in Boulder, Colorado, since 1969. This special section of Optical Engineering is the first one devoted to the entire field of laser damage rather than to a specific part. It is prepared in response to growing interest from the international laser-damage community. Some papers in this special section were presented at the Laser Damage Symposium; others were submitted in response to the general call for papers for this special section. The 18 papers compiled into this special section represent many sides of the broad field of laser-damage research. They consider theoretical studies of the fundamental mechanisms of laser damage including laser-driven electron dynamics in solids (O. Brenk and B. Rethfeld; A. Nikiforov, A. Epifanov, and S. Garnov; T. Apostolova et al.), modeling of propagation effects for ultrashort high-intensity laser pulses (J. Gulley), an overview of mechanisms of inclusion-induced damage (M. Koldunov and A. Manenkov), the formation of specific periodic ripples on a metal surface by femtosecond laser pulses (M. Ahsan and M. Lee), and the laser-plasma effects on damage in glass (Y. Li et al). Material characterization is represented by the papers devoted to accurate and reliable measurements of absorption with special emphasis on thin films (C. Mühlig and S. Bublitz; B. Cho, E. Danielewicz, and J. Rudisill; W. Palm et al; and J. Lu et al.). Statistical treatment of measurements of the laser-damage threshold (J. Arenberg) and the relationship to damage mechanisms (F. Wagner et al.) represent the large subfield of laser-damage measurements. Various aspects of multilayer coating and thin-film characterization are considered in papers by B. Cho, J. Rudisill, and E. Danielewicz (spectral shift in multilayer mirrors) and R. Weber et al. (novel approach to damage studies based on third-harmonic generation microscopy). Of special interest for readers is the paper by C. Stolz that summarizes the results of four “thin-film damage competitions” organized as a part of the Laser Damage Symposium. Another paper is devoted to thermal annealing of damage precursors (N. Shen et al.). Finally, the influence of nano-size contamination on initiation of laser damage by ultrashort pulses is considered in paper of V. Komolov et al.

Vitaly Gruzdev, Michelle D. Shinn

2012-12-01T23:59:59.000Z

226

SLAC All Access: Laser Labs  

SciTech Connect (OSTI)

From supermarket checkouts to video game consoles, lasers are ubiquitous in our lives. Here at SLAC, high-power lasers are critical to the cutting-edge research conducted at the laboratory. But, despite what you might imagine, SLAC's research lasers bear little resemblance to the blasters and phasers of science fiction. In this edition of All Access we put on our safety goggles for a peek at what goes on inside some of SLAC's many laser labs. LCLS staff scientist Mike Minitti and SLAC laser safety officer Mike Woods detail how these lasers are used to study the behavior of subatomic particles, broaden our understanding of cosmic rays and even unlock the mysteries of photosynthesis.

Minitti, Mike; Woods Mike

2013-03-01T23:59:59.000Z

227

Light intensity compressor  

DOE Patents [OSTI]

In a system for recording images having vastly differing light intensities over the face of the image, a light intensity compressor is provided that utilizes the properties of twisted nematic liquid crystals to compress the image intensity. A photoconductor or photodiode material that is responsive to the wavelength of radiation being recorded is placed adjacent a layer of twisted nematic liquid crystal material. An electric potential applied to a pair of electrodes that are disposed outside of the liquid crystal/photoconductor arrangement to provide an electric field in the vicinity of the liquid crystal material. The electrodes are substantially transparent to the form of radiation being recorded. A pair of crossed polarizers are provided on opposite sides of the liquid crystal. The front polarizer linearly polarizes the light, while the back polarizer cooperates with the front polarizer and the liquid crystal material to compress the intensity of a viewed scene. Light incident upon the intensity compressor activates the photoconductor in proportion to the intensity of the light, thereby varying the field applied to the liquid crystal. The increased field causes the liquid crystal to have less of a twisting effect on the incident linearly polarized light, which will cause an increased percentage of the light to be absorbed by the back polarizer. The intensity of an image may be compressed by forming an image on the light intensity compressor.

Rushford, Michael C. (Livermore, CA)

1990-01-01T23:59:59.000Z

228

Attenuation of laser power of a focused Gaussian beam during interaction between a laser and powder in coaxial laser cladding  

Science Journals Connector (OSTI)

The power of a focused laser beam with a Gaussian intensity profile attenuated by powder in coaxial laser cladding is investigated experimentally and theoretically, and its resolution model is developed. With some assumptions, it is concluded that the attenuation of laser power is an exponential function and is determined by the powder feed rate, particle moving speed, spraying angles and waist positions and diameters of the laser beam and powder flow, grain diameter and run of the laser beam through the powder flow. The attenuation of laser power increases with powder feed rate or run of laser beam through the powder flow. In the experiment presented, 300?W laser power from a focused Gaussian beam is attenuated by a coaxial powder flow. The experimental results agree well with the values calculated with the developed model.

Jichang Liu; Lijun Li; Yuanzhong Zhang; Xiaozhu Xie

2005-01-01T23:59:59.000Z

229

Resonantly pumped optical pumping injection cavity lasers  

E-Print Network [OSTI]

An optical parametric oscillator is tuned to the resonance wavelength of the etalon in an optical pumping injection cavity (OPIC) laser with a type-II "W" active region, thereby minimizing the threshold pump intensity and ...

Santilli, Michael Robert; McAlpine, T. C.; Greene, K. R.; Olafsen, L. J.; Bewley, W. W.; Felix, C. L.; Vurgaftman, I.; Meyer, J. R.; Lee, H.; Martinelli, R. U.

2004-11-01T23:59:59.000Z

230

Effect of the laser wavefront in a laser-plasma accelerator  

E-Print Network [OSTI]

A high repetition rate electron source was generated by tightly focusing kHz, few-mJ laser pulses into an underdense plasma. This high intensity laser-plasma interaction led to stable electron beams over several hours but with strikingly complex transverse distributions even for good quality laser focal spots. Analysis of the experimental data, along with results of PIC simulations demonstrate the role of the laser wavefront on the acceleration of electrons. Distortions of the laser wavefront cause spatial inhomogeneities in the out-of-focus laser distribution and consequently, the laser pulse drives an inhomogenous transverse wakefield whose focusing/defocusing properties affect the electron distribution. These findings explain the experimental results and suggest the possibility of controlling the electron spatial distribution in laser-plasma accelerators by tailoring the laser wavefront.

Beaurepaire, B; Bocoum, M; Böhle, F; Jullien, A; Rousseau, J-P; Lefrou, T; Douillet, D; Iaquaniello, G; Lopez-Martens, R; Lifschitz, A; Faure, J

2015-01-01T23:59:59.000Z

231

The Intense Radiation Gas  

E-Print Network [OSTI]

We present a new dispersion relation for photons that are nonlinearly interacting with a radiation gas of arbitrary intensity due to photon-photon scattering. It is found that the photon phase velocity decreases with increasing radiation intensity, it and attains a minimum value in the limit of super-intense fields. By using Hamilton's ray equations, a self-consistent kinetic theory for interacting photons is formulated. The interaction between an electromagnetic pulse and the radiation gas is shown to produce pulse self-compression and nonlinear saturation. Implications of our new results are discussed.

M. Marklund; P. K. Shukla; B. Eliasson

2005-03-08T23:59:59.000Z

232

Traveling-wave laser-produced-plasma energy source for photoionization laser pumping and lasers incorporating said  

DOE Patents [OSTI]

A traveling-wave, laser-produced-plasma, energy source used to obtain single-pass gain saturation of a photoionization pumped laser. A cylindrical lens is used to focus a pump laser beam to a long line on a target. Grooves are cut in the target to present a surface near normal to the incident beam and to reduce the area, and hence increase the intensity and efficiency, of plasma formation.

Sher, Mark H. (Los Altos, CA); Macklin, John J. (Stanford, CA); Harris, Stephen E. (Palo Alto, CA)

1989-09-26T23:59:59.000Z

233

Laser-assisted nuclear photoeffect  

E-Print Network [OSTI]

Proton emission from nuclei via the nuclear photoeffect in the combined electromagnetic fields of a gamma-ray photon and an intense laser wave is studied. An S-matrix approach to the process is developed by utilizing methods known from the theory of nonperturbative laser-atom interactions. As a specific example, photo-proton ejection from halo nuclei is considered. We show that, due to the presence of the laser field, rich sideband structures arise in the photo-proton energy spectra. Their dependence on the parameters and relative orientation of the photon fields is discussed.

Anis Dadi; Carsten Müller

2012-04-17T23:59:59.000Z

234

Laser ablation based fuel ignition  

DOE Patents [OSTI]

There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

1998-01-01T23:59:59.000Z

235

Laser ablation based fuel ignition  

DOE Patents [OSTI]

There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition. 3 figs.

Early, J.W.; Lester, C.S.

1998-06-23T23:59:59.000Z

236

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. The beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being recombined with the first portion after a delay before injection into the ignitor laser. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2002-01-01T23:59:59.000Z

237

Laser focus compensating sensing and imaging device  

DOE Patents [OSTI]

A laser focus compensating sensing and imaging device permits the focus of a single focal point of different frequency laser beams emanating from the same source point. In particular it allows the focusing of laser beam originating from the same laser device but having differing intensities so that a low intensity beam will not convert to a higher frequency when passing through a conversion crystal associated with the laser generating device. The laser focus compensating sensing and imaging device uses a Cassegrain system to fold the lower frequency, low intensity beam back upon itself so that it will focus at the same focal point as a high intensity beam. An angular tilt compensating lens is mounted about the secondary mirror of the Cassegrain system to assist in alignment. In addition cameras or CCD's are mounted with the primary mirror to sense the focused image. A convex lens is positioned co-axial with the Cassegrain system on the side of the primary mirror distal of the secondary for use in aligning a target with the laser beam. A first alternate embodiment includes a Cassegrain system using a series of shutters and an internally mounted dichroic mirror. A second alternate embodiment uses two laser focus compensating sensing and imaging devices for aligning a moving tool with a work piece.

Vann, C.S.

1993-08-31T23:59:59.000Z

238

Femtosecond Near-Infrared Laser Desorption of Multilayer Benzene on Pt{111}: A Molecular Newton's Cradle?  

E-Print Network [OSTI]

Femtosecond Near-Infrared Laser Desorption of Multilayer Benzene on Pt{111}: A Molecular Newton Recently, the intense near-infrared laser desorption of intact benzene molecules has been reported.1 Three, 1999; In Final Form: February 11, 2000 Velocity distributions resulting from the intense, near-IR laser

Levis, Robert J.

239

Page 1Laser Safety Training Laser Institute of America Laser Safety Laser Institute of America  

E-Print Network [OSTI]

Page 1Laser Safety Training © Laser Institute of America 1 Laser Safety © Laser Institute of America Laser Safety: Hazards, Bioeffects, and Control Measures Laser Institute of America Gus Anibarro Education Manager 2Laser Safety © Laser Institute of America Laser Safety Overview Laser Safety Accidents

Farritor, Shane

240

Semiconductor Physics at the Optical Sciences Center  

Science Journals Connector (OSTI)

This talk reviews semiconductor physics experiments and theory at the Optical Sciences Center including optical bistability, femtosecond dynamics, as well as semiconductor laser...

Koch, Stephan W

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Laser induced electron acceleration in vacuum K. P. Singha)  

E-Print Network [OSTI]

Laser induced electron acceleration in vacuum K. P. Singha) Department of Physics, Indian Institute acceleration by a plane polarized laser wave has been studied in vacuum. Relativistic equations of motion have been solved exactly for electron trajectory and energy as a function of laser intensity, phase

Singh, Kunwar Pal

242

Raman Amplification of Laser Pulses in Microcapillary Plasmas  

E-Print Network [OSTI]

of overcoming the power limit of current chirped-pulse-amplification (CPA) CP641, X-Ray Lasers 2002: 8th International Conference on X-Ray Lasers, edited by J. J. Rocca et al. > 2002American Institute of Physics 0 of the optics. Such Raman amplifiers can be useful to produce ultra-intense laser pulses for pumping soft x-ray

243

Nonlinear formation of holographic images of obscurations in laser beams  

E-Print Network [OSTI]

Nonlinear formation of holographic images of obscurations in laser beams C. Clay Widmayer, David of obscurations in laser beams. The predictions of the model are found to be in good agreement with measurements the intensity and fluence of the beam at each component in the laser chain. Dam- age threats to the system can

244

Multiphoton detachment of H-. II. Intensity-dependent photodetachment rates and threshold behavior—complex-scaling generalized pseudospectral method  

E-Print Network [OSTI]

intensity considered ranges from 1 to 40 GW/cm2 and the laser frequency covers 0.20–0.42 eV (in the c.m. frame). Finally we perform a simulation of intensity-averaged multiphoton detachment rates by considering the experimental conditions of the laser and H...

Chu, Shih-I; Wang, Jingyan; Laughlin, Cecil

1994-10-01T23:59:59.000Z

245

Laser microphone  

DOE Patents [OSTI]

A microphone for detecting sound pressure waves includes a laser resonator having a laser gain material aligned coaxially between a pair of first and second mirrors for producing a laser beam. A reference cell is disposed between the laser material and one of the mirrors for transmitting a reference portion of the laser beam between the mirrors. A sensing cell is disposed between the laser material and one of the mirrors, and is laterally displaced from the reference cell for transmitting a signal portion of the laser beam, with the sensing cell being open for receiving the sound waves. A photodetector is disposed in optical communication with the first mirror for receiving the laser beam, and produces an acoustic signal therefrom for the sound waves.

Veligdan, James T. (Manorville, NY)

2000-11-14T23:59:59.000Z

246

Predicting threshold and location of laser damage on optical surfaces  

DOE Patents [OSTI]

An apparatus useful in the prediction of the damage threshold of various optical devices, the location of weak spots on such devices and the location, identification, and elimination of optical surface impurities comprising, a focused and pulsed laser, an photo electric detector/imaging means, and a timer. The weak spots emit photoelectrons when subjected to laser intensities that are less than the intensity actually required to produce the damage. The weak spots may be eliminated by sustained exposure to the laser beam.

Siekhaus, Wigbert (Berkeley, CA)

1987-01-01T23:59:59.000Z

247

Compact Quantum Cascade Laser Transmitter  

SciTech Connect (OSTI)

): In this paper we present design considerations, thermal and optical modeling results, and device performance for a ruggedized, compact laser transmitter that utilizes a room temperature quantum cascade (QC) laser source. The QC laser transmitter is intended for portable mid-infrared (3-12 µm) spectroscopy applications, where the atmospheric transmission window is relatively free of water vapor interference and where the molecular rotational vibration absorption features can be used to detect and uniquely identify chemical compounds of interest. Initial QC laser-based sensor development efforts were constrained by the complications of cryogenic operation. However, improvements in both QC laser designs and fabrication processes have provided room-temperature devices that now enable significant miniaturization and integration potential for national security, environmental monitoring, atmospheric science, and industrial safety applications.

Anheier, Norman C.; Hatchell, Brian K.; Gervais, Kevin L.; Wojcik, Michael D.; Krishnaswami, Kannan; Bernacki, Bruce E.

2009-04-01T23:59:59.000Z

248

Le Bail Intensity Extraction  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Le Bail Intensity Extraction Le Bail Intensity Extraction Presentation Goal Introduce the concepts behind LeBail fitting; why it is useful and how to perform a Le Bail fit with GSAS. Format: PDF slides or a RealPlayer video of the slides with accompanying audio and a demo video that shows how a Le Bail fit is performed. Presentation Outline What is the Le Bail method? Other approaches Why use the Le Bail method? Parameter fitting with Le Bail intensity extraction Le Bail refinement strategies Avoiding problems with background fitting: BKGEDIT Demo: an example Le Bail fit Links Le Bail lecture Slides (as PDF file) FlashMovie presentation with index (best viewed with 1024x768 or better screen resolution) FlashMovie file (800x600 pixels) Le Bail demo FlashMovie presentation with index (best viewed with 1024x768 or

249

Focus issue introduction: Laser Ignition Conference  

Science Journals Connector (OSTI)

The purpose of this feature issue is to share information on laser ignition and related sciences and technologies. This feature offers five papers in the field that cover aspects of...

Taira, Takunori; Furutani, Hirohide; Guo, Chunlei; Wintner, Ernst; Akamatsu, Fumiteru; Lucht, Robert; Washio, Kunihiko

2014-01-01T23:59:59.000Z

250

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In a third embodiment, alternating short and long pulses of light from the excitation light source are directed into the ignitor laser. Each of the embodiments of the invention can be multiplexed so as to provide laser light energy sequentially to more than one ignitor laser.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2003-01-01T23:59:59.000Z

251

Title of Document: LONGITUDINAL CONTROL OF INTENSE CHARGED PARTICLE BEAMS  

E-Print Network [OSTI]

ABSTRACT Title of Document: LONGITUDINAL CONTROL OF INTENSE CHARGED PARTICLE BEAMS Brian Louis, accelerator facilities are demanding beams with higher quality. Applications such as Free Electron Lasers energy spread throughout the accelerator. Fluctuations in beam energy or density at the low-energy side

Anlage, Steven

252

Applications of soft x-ray lasers  

SciTech Connect (OSTI)

The high brightness and short pulse duration of soft x-ray lasers provide unique advantages for novel applications. Imaging of biological specimens using x-ray lasers has been demonstrated by several groups. Other applications to fields such as chemistry, material science, plasma diagnostics, and lithography are beginning to emerge. We review the current status of soft x-ray lasers from the perspective of applications, and present an overview of the applications currently being developed.

Skinner, C.H.

1993-08-01T23:59:59.000Z

253

Interaction between laser beam and powder stream in the process of laser cladding with powder feeding  

Science Journals Connector (OSTI)

Based on Lambert–Beer theorem and Mie's theory, the attenuation of laser power by a powder stream was calculated and the laser intensity distribution at the laser spot on the surface of a workpiece was obtained. Simultaneously, the temperature distribution of the powder particles arriving at different sites on the surface of the workpiece was computed following the heat equilibrium principle. The computed results revealed that for a given stream spread and speed of powder particles, the intensity distribution of the laser spot and the temperature distribution of the powder particles reaching the surface of the workpiece are both greatly affected by the powder feeding rate and the feeding angle. It is suggested that the presented results should be considered in the laser cladding process in order to control the dynamic processes in a laser molten pool.

Yan-Lu Huang; Gong-Ying Liang; Jun-Yi Su; Jian-Guo Li

2005-01-01T23:59:59.000Z

254

Zone folding effect in Raman G-band intensity of twisted bilayer graphene  

E-Print Network [OSTI]

The G-band Raman intensity is calculated for twisted bilayer graphene as a function of laser excitation energy based on the extended tight binding method. Here we explicitly consider the electron-photon and electron-phonon ...

Dresselhaus, Mildred

255

Limiting effects on laser compression by resonant backward Raman scattering in modern experimentsa)  

E-Print Network [OSTI]

amplifier by high intensity radiation is avoided by the temporal stretching of the laser pulse, its the cost of the CPA laser and CPA technology approaches its practical limit. Alternatively, plasma can

256

Effect of Beam Quality on the Scaling of High-Energy Flow Lasers  

Science Journals Connector (OSTI)

The maximum output power from high-energy flow lasers is primarily determined by the ... field intensity, however, depends on the beam quality that can be achieved with the laser ... of gas flow inhomogeneities o...

W. L. Bohn; Th. Hall

1987-01-01T23:59:59.000Z

257

Statistical analysis and optimization of processing parameters in high-power direct diode laser cladding  

Science Journals Connector (OSTI)

High-power direct diode laser (HPDDL) offers a wide laser beam with a top-hat intensity distribution, ... making it an ideal tool for large-area cladding. In this study, a systemic study on the HPDDL cladding pro...

Shuang Liu; Radovan Kovacevic

2014-09-01T23:59:59.000Z

258

Energy Intensity Strategy  

E-Print Network [OSTI]

Our presentation will cover how we began the journey of conserving energy at our facility. We’ll discuss a basic layout of our energy intensity plan and the impact our team has had on the process, what tools we’re using, what goals have been...

Rappolee, D.; Shaw, J.

2008-01-01T23:59:59.000Z

259

Laser-plasma interactions for fast ignition  

E-Print Network [OSTI]

In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multi-dimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporal evolution. Scaling with irradiation conditions such as laser intensity are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the compa...

Kemp, A J; Debayle, A; Johzaki, T; Mori, W B; Patel, P K; Sentoku, Y; Silva, L O

2013-01-01T23:59:59.000Z

260

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In the embodiment of the invention claimed herein, the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Unlocking energy intensive habits  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

energy intensive habits energy intensive habits Presentation at LBL Oct 10, 2013 by Hal Wilhite Professor and Research Director University of Oslo Centre for Development and the Environment Source: WWF US EIA Outlook 2011 Conventional framing of the energy consumption and savings * Sovereign consumers * Economically rational and persistentely reflexive. * Uninfluenced by social and material conditions of everyday life * Focus on efficiency and not on size and volume which is for the most part treated as an indifferent variable Cognitive reductionism The change of frame * From individual to socio-material * From rational/reflexive experience-based (practical) knowledge * From efficiency to reduction A theory of habit * Acknowledges the role of lived experience (history, both cultural and personal) in forming

262

The intensity of motivation  

E-Print Network [OSTI]

rearranged before they were repeated in reverse sequence. Electrocardiographic T-wave amplitude (TWA) and changes were monitored during a 15-sec anticipatory phase, as well as during each 15-second mental manipulation phase. (This ensured that the measures..., and the subject was surreptitiously observed. The high-self-esteem subjects were observed to do more practice www.annualreviews.org/aronline Annual Reviews INTENSITY OF MOTIVATION 121 problems for the difficult- than for the easy-to-please experimenter...

Brehm, Jack W.; Self, E. A.

1989-01-01T23:59:59.000Z

263

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source capable of producing alternating beams of light having different wavelengths is used in tandem with one or more ignitor lasers to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using the single remote excitation light source for pumping one or more small lasers located proximate to one or more fuel combustion zones with alternating wavelengths of light.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2002-01-01T23:59:59.000Z

264

Treatment of metal surfaces with excimer laser radiation for radiative applications  

Science Journals Connector (OSTI)

In this study the effects of intense excimer laser irradiation (108–109 W cm?2) on some radiative properties of copper, aluminum, magnesium, tantalum,...

Kinsman, G; Duley, W W

1993-01-01T23:59:59.000Z

265

ON COMPUTING UPPER LIMITS TO SOURCE INTENSITIES  

SciTech Connect (OSTI)

A common problem in astrophysics is determining how bright a source could be and still not be detected in an observation. Despite the simplicity with which the problem can be stated, the solution involves complicated statistical issues that require careful analysis. In contrast to the more familiar confidence bound, this concept has never been formally analyzed, leading to a great variety of often ad hoc solutions. Here we formulate and describe the problem in a self-consistent manner. Detection significance is usually defined by the acceptable proportion of false positives (background fluctuations that are claimed as detections, or Type I error), and we invoke the complementary concept of false negatives (real sources that go undetected, or Type II error), based on the statistical power of a test, to compute an upper limit to the detectable source intensity. To determine the minimum intensity that a source must have for it to be detected, we first define a detection threshold and then compute the probabilities of detecting sources of various intensities at the given threshold. The intensity that corresponds to the specified Type II error probability defines that minimum intensity and is identified as the upper limit. Thus, an upper limit is a characteristic of the detection procedure rather than the strength of any particular source. It should not be confused with confidence intervals or other estimates of source intensity. This is particularly important given the large number of catalogs that are being generated from increasingly sensitive surveys. We discuss, with examples, the differences between these upper limits and confidence bounds. Both measures are useful quantities that should be reported in order to extract the most science from catalogs, though they answer different statistical questions: an upper bound describes an inference range on the source intensity, while an upper limit calibrates the detection process. We provide a recipe for computing upper limits that applies to all detection algorithms.

Kashyap, Vinay L.; Siemiginowska, Aneta [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Van Dyk, David A.; Xu Jin [Department of Statistics, University of California, Irvine, CA 92697-1250 (United States); Connors, Alanna [Eureka Scientific, 2452 Delmer Street, Suite 100, Oakland, CA 94602-3017 (United States); Freeman, Peter E. [Department of Statistics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Zezas, Andreas, E-mail: vkashyap@cfa.harvard.ed, E-mail: asiemiginowska@cfa.harvard.ed, E-mail: dvd@ics.uci.ed, E-mail: jinx@ics.uci.ed, E-mail: aconnors@eurekabayes.co, E-mail: pfreeman@cmu.ed, E-mail: azezas@cfa.harvard.ed [Physics Department, University of Crete, P.O. Box 2208, GR-710 03, Heraklion, Crete (Greece)

2010-08-10T23:59:59.000Z

266

Imaging System With Confocally Self-Detecting Laser.  

DOE Patents [OSTI]

The invention relates to a confocal laser imaging system and method. The system includes a laser source, a beam splitter, focusing elements, and a photosensitive detector. The laser source projects a laser beam along a first optical path at an object to be imaged, and modulates the intensity of the projected laser beam in response to light reflected from the object. A beam splitter directs a portion of the projected laser beam onto a photodetector. The photodetector monitors the intensity of laser output. The laser source can be an electrically scannable array, with a lens or objective assembly for focusing light generated by the array onto the object of interest. As the array is energized, its laser beams scan over the object, and light reflected at each point is returned by the lens to the element of the array from which it originated. A single photosensitive detector element can generate an intensity-representative signal for all lasers of the array. The intensity-representative signal from the photosensitive detector can be processed to provide an image of the object of interest.

Webb, Robert H. (Lincoln, MA); Rogomentich, Fran J. (Concord, MA)

1996-10-08T23:59:59.000Z

267

Fusion pumped laser  

DOE Patents [OSTI]

The apparatus of this invention may comprise a system for generating laser radiation from a high-energy neutron source. The neutron source is a tokamak fusion reactor generating a long pulse of high-energy neutrons and having a temperature and magnetic field effective to generate a neutron flux of at least 10/sup 15/ neutrons/cm/sup 2//center dot/s. Conversion means are provided adjacent the fusion reactor at a location operable for converting the high-energy neutrons to an energy source with an intensity and energy effective to excite a preselected lasing medium. A lasing medium is spaced about and responsive to the energy source to generate a population inversion effective to support laser oscillations for generating output radiation. 2 figs., 2 tabs.

Pappas, D.S.

1987-07-31T23:59:59.000Z

268

SLAC All Access: Atomic, Molecular and Optical Science Instrument  

ScienceCinema (OSTI)

John Bozek, a staff scientist at SLAC's Linac Coherent Light Source (LCLS) X-ray laser who manages the LCLS Soft X-ray Department, takes us behind the scenes at the Atomic, Molecular and Optical Science (AMO) instrument, the first of six experimental stations now operating at LCLS. Samples used in AMO experiments include atoms, molecules, clusters, and nanoscale objects such as protein crystals or viruses. Science performed at AMO includes fundamental studies of light-matter interactions in the extreme X-ray intensity of the LCLS pules, time-resolved studies of increasingly charged states of atoms and molecules, X-ray diffraction imaging of nanocrystals, and single-shot imaging of a variety of objects.

Bozek, John

2014-06-03T23:59:59.000Z

269

Coherence theory of the ring laser  

Science Journals Connector (OSTI)

Expressions for the fluctuations and correlations of the light emitted by a ring laser with counter-rotating traveling wave modes are derived theoretically. It is shown that the competition of the two modes for the excited atomic population leads to negative correlations between their intensity fluctuations, whose magnitude depends on the detuning of the laser cavity from the atomic line center. As a result of the mode competition, the relative intensity fluctuations do not die out in general as the working point of the laser is raised above threshold at line center, and the emitted light does not become fully coherent as in a conventional laser. The two-time amplitude and intensity correlation functions of the light are calculated at line center, and are shown to be expressible in terms of the eigenfunctions and eigenvalues of a certain Schrödinger equation, in complete analogy with the theory of the single-mode laser. However, the intensity correlation time increases with pump parameter above threshold, unlike that for the single-mode laser.

M. M- Tehrani and L. Mandel

1978-02-01T23:59:59.000Z

270

Optical diagnostics integrated with laser spark delivery system  

DOE Patents [OSTI]

A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

Yalin, Azer (Fort Collins, CO); Willson, Bryan (Fort Collins, CO); Defoort, Morgan (Fort Collins, CO); Joshi, Sachin (Fort Collins, CO); Reynolds, Adam (Fort Collins, CO)

2008-09-02T23:59:59.000Z

271

Physics of Laser-driven plasma-based acceleration  

SciTech Connect (OSTI)

The physics of plasma-based accelerators driven by short-pulse lasers is reviewed. This includes the laser wake-field accelerator, the plasma beat wave accelerator, the self-modulated laser wake-field accelerator, and plasma waves driven by multiple laser pulses. The properties of linear and nonlinear plasma waves are discussed, as well as electron acceleration in plasma waves. Methods for injecting and trapping plasma electrons in plasma waves are also discussed. Limits to the electron energy gain are summarized, including laser pulse direction, electron dephasing, laser pulse energy depletion, as well as beam loading limitations. The basic physics of laser pulse evolution in underdense plasmas is also reviewed. This includes the propagation, self-focusing, and guiding of laser pulses in uniform plasmas and plasmas with preformed density channels. Instabilities relevant to intense short-pulse laser-plasma interactions, such as Raman, self-modulation, and hose instabilities, are discussed. Recent experimental results are summarized.

Esarey, Eric; Schroeder, Carl B.

2003-06-30T23:59:59.000Z

272

Science Showcase | OSTI, US Dept of Energy, Office of Scientific and  

Office of Scientific and Technical Information (OSTI)

Science Showcase Science Showcase 2013 2012 2011 2010 2009 December DOE Science Showcase - Light-emitting Diode (LED) Lighting Research November DOE Science Showcase - Gamma-Ray Bursts October DOE Science Showcase - Bayesian Inference September DOE Science Showcase - Understanding High-Temperature Superconductors August DOE Science Showcase - Exciting Higgs Boson Research July DOE Science Showcase - DOE's Smart Grid Research June DOE Science Showcase - DOE Plasma Research May DOE Science Showcase - Oil Shale Research April DOE Science Showcase - Fission Theory March DOE Science Showcase - Free-Electron Lasers February DOE Science Showcase - Heat Pump Research January DOE Science Showcase - Monte Carlo Methods December DOE Science Showcase - Quantum Computer Hardware November DOE Science Showcase - Metamaterials

273

Floquet–Liouville supermatrix approach. II. Intensity?dependent generalized nonlinear optical susceptibilities  

E-Print Network [OSTI]

We present a practical n o n p e r t u r b a t i v e method for e x a c t treatment of i n t e n s i t y?d e p e n d e n t generalized nonlinear optical susceptibilities ?(?) in intense polychromatic fields, valid for arbitrary laser intensities...

Chu, Shih-I; Wang, Kwanghsi

1987-08-15T23:59:59.000Z

274

Laser device  

DOE Patents [OSTI]

A laser device includes a virtual source configured to aim laser energy that originates from a true source. The virtual source has a vertical rotational axis during vertical motion of the virtual source and the vertical axis passes through an exit point from which the laser energy emanates independent of virtual source position. The emanating laser energy is collinear with an orientation line. The laser device includes a virtual source manipulation mechanism that positions the virtual source. The manipulation mechanism has a center of lateral pivot approximately coincident with a lateral index and a center of vertical pivot approximately coincident with a vertical index. The vertical index and lateral index intersect at an index origin. The virtual source and manipulation mechanism auto align the orientation line through the index origin during virtual source motion.

Scott, Jill R. (Idaho Falls, ID); Tremblay, Paul L. (Idaho Falls, ID)

2008-08-19T23:59:59.000Z

275

ARM - Publications: Science Team Meeting Documents  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Radiation Measurement (ARM) Science Team Meeting The Unmanned Aerospace Vehicle (UAV) Program conducted an ARM Enhanced Shortwave Experiment (ARESE) II Intensive...

276

High intensity femtosecond enhancement cavities  

E-Print Network [OSTI]

To produce extreme ultraviolet radiation via high harmonic generation (HHG) in rare gases, light intensities in excess of 1014 W/cm 2 are required. Usually such high intensity are obtained by parametric amplification of ...

Abram, Gilberto

2009-01-01T23:59:59.000Z

277

Nonlinear magneto-optic polarization rotation with intense laser fields  

E-Print Network [OSTI]

. A polarization analyzer P2 is placed after the cell and titled 45 degrees with respect to the polarizer. Photodiodes PD1 and PD2 detect the light from both chan- nels of the analyzer, allowing simultaneous measurements of the polarization...

Hsu, Paul S.; Patnaik, Anil K.; Welch, George R.

2008-01-01T23:59:59.000Z

278

Laser Systems for Orbital Debris Removal  

SciTech Connect (OSTI)

The use of a ground based laser for space debris cleaning was investigated by the ORION project in 1996. Since that study the greatest technological advance in the development of high energy pulsed laser systems has taken place within the NIF project at LLNL. The proposed next laser system to follow the NIF at LLNL will be a high rep rate version of the NIF based on diode-pumping rather than flashlamp excitation; the so called 'LIFE' laser system. Because a single 'LIFE' beamline could be built up in a few year time frame, and has performance characteristics relevant to the space debris clearing problem, such a beamline could enable a near term demonstration of space debris cleaning. Moreover, the specifics of debris cleaning make it possible to simplify the LIFE laser beyond what is required for a fusion drive laser, and so substantially reduce its cost. Starting with the requirements for laser intensity on the target, and then considering beam delivery, we will flow back the laser requirements needed for space debris cleaning. Using these derived requirements we will then optimize the pulse duration, the operational regime, and the output pulse energy of the laser with a focus of simplifying its overall design. Anticipated simplifications include operation in the heat capacity regime, eliminating cooling requirements on the laser gain slabs, and relaxing B-integral and birefrigence requirements.

Rubenchik, A M; Barty, C P; Beach, R J; Erlandson, A C; Caird, J A

2010-02-05T23:59:59.000Z

279

Laser goniometer  

DOE Patents [OSTI]

The laser goniometer is an apparatus which permits an operator to sight along a geologic feature and orient a collimated lamer beam to match the attitude of the feature directly. The horizontal orientation (strike) and the angle from horizontal (dip), are detected by rotary incremental encoders attached to the laser goniometer which provide a digital readout of the azimuth and tilt of the collimated laser beam. A microprocessor then translates the square wave signal encoder outputs into an ASCII signal for use by data recording equipment.

Fairer, George M. (Boulder, CO); Boernge, James M. (Lakewood, CO); Harris, David W. (Lakewood, CO); Campbell, DeWayne A. (Littleton, CO); Tuttle, Gene E. (Littleton, CO); McKeown, Mark H. (Golden, CO); Beason, Steven C. (Lakewood, CO)

1993-01-01T23:59:59.000Z

280

CHALLENGES IN DATA INTENSIVE ANALYSIS AT SCIENTIFIC EXPERIMENTAL USER FACILITIES  

SciTech Connect (OSTI)

This chapter will discuss the critical data intensive analysis and visualiza-tion challenges faced by the experimental science community at large scale and laboratory based facilities. The chapter will further highlight initial solutions under development through community efforts and lay out perspectives for the future, such as the potential of more closely linked experimental and computational science approaches, methods to achieve real time analysis capabilities and the challenges and opportunities of data integration across experimental scales, levels of theory and varying techniques.

Kleese van Dam, Kerstin; Li, Dongsheng; Miller, Stephen D.; Cobb, John W.; Green, Mark L.; Ruby, Catherine L.

2011-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Materials Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Materials Science science-innovationassetsimagesicon-science.jpg Materials Science National security depends on science and technology. The United States relies on Los Alamos...

282

Coherence delay augmented laser beam homogenizer  

DOE Patents [OSTI]

The geometrical restrictions on a laser beam homogenizer are relaxed by ug a coherence delay line to separate a coherent input beam into several components each having a path length difference equal to a multiple of the coherence length with respect to the other components. The components recombine incoherently at the output of the homogenizer, and the resultant beam has a more uniform spatial intensity suitable for microlithography and laser pantogography. Also disclosed is a variable aperture homogenizer, and a liquid filled homogenizer.

Rasmussen, P.; Bernhardt, A.

1993-06-29T23:59:59.000Z

283

Coherence delay augmented laser beam homogenizer  

DOE Patents [OSTI]

The geometrical restrictions on a laser beam homogenizer are relaxed by ug a coherence delay line to separate a coherent input beam into several components each having a path length difference equal to a multiple of the coherence length with respect to the other components. The components recombine incoherently at the output of the homogenizer, and the resultant beam has a more uniform spatial intensity suitable for microlithography and laser pantogography. Also disclosed is a variable aperture homogenizer, and a liquid filled homogenizer.

Rasmussen, Paul (Livermore, CA); Bernhardt, Anthony (Berkeley, CA)

1993-01-01T23:59:59.000Z

284

Laser-Accelerated Protons with Energy-Dependent Beam Direction  

Science Journals Connector (OSTI)

The spatial distribution of protons, accelerated by intense femtosecond laser pulses interacting with thin target foils under oblique irradiation are investigated. Under certain conditions, the proton beams are directed away from the target normal. This deviation is towards the laser forward direction, with an angle that increases with the level and duration of the amplified spontaneous emission pedestal before the main laser pulse. In addition, for a given laser pulse, this beam deviation increases with proton energy. The observations are discussed in terms of different electron acceleration mechanisms and target normal sheath acceleration, in combination with a laser-controllable shock wave locally deforming the target rear surface.

F. Lindau; O. Lundh; A. Persson; P. McKenna; K. Osvay; D. Batani; C.-G. Wahlström

2005-10-19T23:59:59.000Z

285

Pulsed Laser Deposition | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Pulsed Laser Deposition Pulsed Laser Deposition EMSL's pulsed laser deposition (PLD) system is designed for epitaxial growth of oxide, ceramic, or synthetic mineral thin films and...

286

Laser barometer  

SciTech Connect (OSTI)

This paper describes an invention of a pressure measuring instrument which uses laser radiation to sense the pressure in an enclosed environment by means of measuring the change in refractive index of a gas - which is pressure dependent.

Abercrombie, K.R.; Shiels, D.; Rash, T.

1998-04-01T23:59:59.000Z

287

LASER ACCELERATORS  

E-Print Network [OSTI]

UNIVERSITY OF CALIFORNIA Accelerator & Fusion Researchat the 1983 Particle Accelerator Conference, Santa Fe, NM,March 21-23, 1983 LASER ACCELERATORS A.M. Sessler TWO-WEEK

Sessler, A.M.

2008-01-01T23:59:59.000Z

288

Laser ignition  

Science Journals Connector (OSTI)

Due to their thermodynamic benefits, second-generation spark-ignition engines with gasoline direct injection systems have ... combination of a spray-guided combustion process with laser-induced ignition allows th...

Bernhard Geringer; Dominikus Klawatsch; Josef Graf; Hans Peter Lenz…

2004-03-01T23:59:59.000Z

289

Laser EYE SURGERY LASIK and Excimer Lasers  

E-Print Network [OSTI]

Laser EYE SURGERY LASIK and Excimer Lasers Michael Hutchins #12;The PROBLEM opia - near sightedness - Laser Assisted in SItu Keratomileusis atomileusis is the procedure of opening the eye and ring the cornea. SIK uses an excimer laser to perform the alterations an er a knife or a femtosecond laser

Fygenson, Deborah Kuchnir

290

Proposed Laser-Based HED physics experiments for Stockpile Stewardship  

SciTech Connect (OSTI)

An analysis of the scientific areas in High Energy Density (HED) physics that underpin the enduring LANL mission in Stockpile Stewardship (SS) has identified important research needs that are not being met. That analysis has included the work done as part of defining the mission need for the High Intensity Laser Laboratory (HILL) LANL proposal to NNSA, LDRD DR proposal evaluations, and consideration of the Predictive Capability Framework and LANL NNSA milestones. From that evaluation, we have identified several specific and scientifically-exciting experimental concepts to address those needs. These experiments are particularly responsive to physics issues in Campaigns 1 and 10. These experiments are best done initially at the LANL Trident facility, often relying on the unique capabilities available there, although there are typically meritorious extensions envisioned at future facilities such as HILL, or the NIF once the ARC short-pulse laser is available at sufficient laser intensity. As the focus of the LANL HEDP effort broadens from ICF ignition of the point design at the conclusion of the National Ignition Campaign, into a more SS-centric effort, it is useful to consider these experiments, which address well-defined issues, with specific scientific hypothesis to test or models to validate or disprove, via unit-physics experiments. These experiments are in turn representative of a possible broad experimental portfolio to elucidate the physics of interest to these campaigns. These experiments, described below, include: (1) First direct measurement of the evolution of particulates in isochorically heated dense plasma; (2) Temperature relaxation measurements in a strongly-coupled plasma; (3) Viscosity measurements in a dense plasma; and (4) Ionic structure factors in a dense plasma. All these experiments address scientific topics of importance to our sponsors, involve excellent science at the boundaries of traditional fields, utilize unique capabilities at LANL, and contribute to the Campaign milestone in 2018. Given their interdisciplinary nature, it is not surprising that these research needs are not being addressed by the other excellent high-energy density physics (HEDP) facilities coming on line, facilities aimed squarely at more established fields and missions. Although energy rich, these facilities deliver radiation (e.g., particle beams for isochoric heating) over a timescale that is too slow in these unit physics experiments to eliminate hydrodynamic evolution of the target plasma during the time it is being created. A theme shared by all of these experiments is the need to quickly create a quasi-homogeneous 'initial state' whose properties and evolution we wish to study. Otherwise, we cannot create unit experiments to isolate the physics of interest and validate the models in our codes, something that cannot be done with the integrated experiments often done in HED. Moreover, these experiments in some cases involve combinations of solid and plasmas, or matter in the warm-dense matter state, where neither the theoretical approximations of solid state or of fully-ionized weakly-coupled plasmas can be used. In all cases, the capability of 'isochoric heating' ('flash' heating at constant density) is important. In some cases, the ability to selectively heat to different degrees different species within a target, whether mixed or adjacent to each other, is critical for the experiment. This capability requires the delivery of very high power densities, which require the conversion of the laser into very short and intense pulses of secondary radiation (electrons, ions, neutrons, x-rays). Otherwise, there is no possibility of a clean experiment to constrain the models, in the cases there are any, or inform the creation of one. Another typical requirement of these experiments is the ability to probe these exotic extreme conditions of matter with flexible and diverse sources of secondary radiation. Without a high-intensity high-power laser with some unique attributes available on Trident today (e.g., ultra-high laser-puls

Benage, John F. [Los Alamos National Laboratory; Albright, Brian J. [Los Alamos National Laboratory; Fernandez, Juan C. [Los Alamos National Laboratory

2012-09-04T23:59:59.000Z

291

Laser Detection Of Material Thickness  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Detection Of Material Thickness Detection Of Material Thickness Laser Detection Of Material Thickness There is provided a method for measuring material thickness. Available for thumbnail of Feynman Center (505) 665-9090 Email Laser Detection Of Material Thickness There is provided a method for measuring material thickness comprising: (a) contacting a surface of a material to be measured with a high intensity short duration laser pulse at a light wavelength which heats the area of contact with the material, thereby creating an acoustical pulse within the material: (b) timing the intervals between deflections in the contacted surface caused by the reverberation of acoustical pulses between the contacted surface and the opposite surface of the material: and (c) determining the thickness of the material by calculating the proportion of

292

Nonlinear optics with focused x-ray lasers  

SciTech Connect (OSTI)

We have investigated the possibility of focusing x-ray lasers with the use of multilayered mirrors or zone plates. The results indicate that x-ray intensities as high as 10{sup 14} W/cm{sup 2} can be achieved by focusing saturated Ne-like x-ray lasers. These intensities should be adequate for studying nonlinear optical phenomena. 9 refs., 2 figs.

DaSilva, L.B.; Muendel, M.H.; Falcone, R.W.; Fields, D.J.; Kortright, J.B.; MacGowan, B.J.; Matthews, D.L.; Mrowka, S.; Shimkaveg, G.M.; Trebes, J.E.

1990-12-12T23:59:59.000Z

293

Physics of Optoelectronic and Plasmonic Devices: Cavities, Waveguides, Modulators and Lasers  

E-Print Network [OSTI]

electronics and optoelectronics: Exploring nanoscale scienceInternational Journal of Optoelectronics 11, 155-168 (impact of plasmonic lasers on optoelectronics integration is

Sorger, Volker J.

2011-01-01T23:59:59.000Z

294

Ion Acceleration by Short Chirped Laser Pulses  

E-Print Network [OSTI]

Direct laser acceleration of ions by short frequency-chirped laser pulses is investigated theoretically. We demonstrate that intense beams of ions with a kinetic energy broadening of about 1 % can be generated. The chirping of the laser pulse allows the particles to gain kinetic energies of hundreds of MeVs, which is required for hadron cancer therapy, from pulses of energies of the order of 100 J. It is shown that few-cycle chirped pulses can accelerate ions more efficiently than long ones, i.e. higher ion kinetic energies are reached with the same amount of total electromagnetic pulse energy.

Li, Jian-Xing; Keitel, Christoph H; Harman, Zoltán

2015-01-01T23:59:59.000Z

295

Laser Program annual report, 1985  

SciTech Connect (OSTI)

This volume presents the unclassified activities and accomplishments of the Inertial Confinement Fusion and Advanced Laser Development elements of the Laser Program at the Lawrence Livermore National Laboratory for the calendar year 1985. This report has been organized into major sections that correspond to our principal technical activities. Section 1 provides an overview. Section 2 comprises work in target theory, design, and code development. Target development and fabrication and the related topics in materials science are contained in Section 3. Section 4 presents work in experiments and diagnostics and includes developments in data acquisition and management capabilities. In Section 5 laser system (Nova) operation and maintenance are discussed. Activities related to supporting laser and optical technologies are described in Section 6. Basic laser research and development is reported in Section 7. Section 8 contains the results of studies in ICF applications where the work reported deals principally with the production of electric power with ICF. Finally, Section 9 is a comprehensive discussion of work to date on solid state lasers for average power applications. Individual sections, two through nine, have been cataloged separately.

Rufer, M.L.; Murphy, P.W. (eds.)

1986-11-01T23:59:59.000Z

296

OPTICAL SCIENCE & ENGINEERINGOPTICAL SCIENCE &ENGINEERINGOPTICAL SCIENCE & ENGINEERINGOPTICAL SCIENCE &ENGINEERING University of New Mexico  

E-Print Network [OSTI]

SCIENCE &ENGINEERING University of New Mexico Abstract:. The injection problem in semiconductor lasers was born in Thessaloniki, Greece. He received the BS in Electrical Engineering from the University. Retired from the Air Force Research Laboratory RD and joined the faculty of the University of New Mexico

New Mexico, University of

297

SCIENCE CHINA Technological Sciences  

E-Print Network [OSTI]

SCIENCE CHINA Technological Sciences © Science China Press and Springer-Verlag Berlin Heidelberg and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China; 2 Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000, China; 3 School of Material Science and Engineering, Georgia Institute

Wang, Zhong L.

298

Laser ablation in analytical chemistry - A review  

SciTech Connect (OSTI)

Laser ablation is becoming a dominant technology for direct solid sampling in analytical chemistry. Laser ablation refers to the process in which an intense burst of energy delivered by a short laser pulse is used to sample (remove a portion of) a material. The advantages of laser ablation chemical analysis include direct characterization of solids, no chemical procedures for dissolution, reduced risk of contamination or sample loss, analysis of very small samples not separable for solution analysis, and determination of spatial distributions of elemental composition. This review describes recent research to understand and utilize laser ablation for direct solid sampling, with emphasis on sample introduction to an inductively coupled plasma (ICP). Current research related to contemporary experimental systems, calibration and optimization, and fractionation is discussed, with a summary of applications in several areas.

Russo, Richard E.; Mao, Xianglei; Liu, Haichen; Gonzalez, Jhanis; Mao, Samuel S.

2001-10-10T23:59:59.000Z

299

Stable plateau formation and Brillouin suppression in laser plasma  

SciTech Connect (OSTI)

Among the variety of ponderomotively induced density structures in laser produced plasmas in one dimension, it is shown by particle-in-cell simulations that the stable plateau formation at critical, subcritical, and above critical density is possible. Stimulated Brillouin backscattering is suppressed with increasing laser intensity.

Mulser, P. [Theoretical Quantum Electronics (TQE), Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Weng, S. M. [Theoretical Quantum Electronics (TQE), Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Department of Physics, Ludwig-Maximilians-Universitaet Muenchen, D-80333 Munich (Germany)

2010-10-15T23:59:59.000Z

300

Vanadium-pumped titanium x-ray laser  

DOE Patents [OSTI]

A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions. 4 figs.

Nilsen, J.

1992-05-26T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Vanadium-pumped titanium x-ray laser  

DOE Patents [OSTI]

A resonantly photo-pumped x-ray laser (10) is formed of a vanadium (12) and titanium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state neon-like titanium ions (34) are resonantly photo-pumped by line emission from fluorine-like vanadium ions (32).

Nilsen, Joseph (Livermore, CA)

1992-01-01T23:59:59.000Z

302

Quantum Reservoir Engineering with Laser Cooled Trapped Ions  

Science Journals Connector (OSTI)

We show how to design different couplings between a single ion trapped in a harmonic potential and an environment. The coupling is due to the absorption of a laser photon and subsequent spontaneous emission. The variation of the laser frequencies and intensities allows one to “engineer” the coupling and select the master equation describing the motion of the ion.

J. F. Poyatos; J. I. Cirac; P. Zoller

1996-12-02T23:59:59.000Z

303

Laser Safety Introduction  

E-Print Network [OSTI]

Laser Safety #12;Introduction · A Laser is a device that controls the way energized atoms release photons. · LASER is an acronym for "Light Amplification by Stimulated Emission of Radiation" · The light emitted by a laser is non

McQuade, D. Tyler

304

Along the Laser Beampath  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

8 20 | Next | Last Back to Index NIF Laser Bay Each NIF laser bay is 122 meters (400 feet) long and contains 96 beamlines. This side view of Laser Bay 2 shows the four-high laser...

305

Corpuscular theory of intensity noise with gain compression  

Science Journals Connector (OSTI)

When light from a laser is fully absorbed by an ideal detector, the detected current exhibits a fluctuation called here ‘‘photonic noise.’’ The spectral density of Iintensity noiseR, defined as the difference of the photonic-noise spectral density and a term corresponding to the shot-noise level, is negative for sub-Poissonian statistics. The usefulness of the relative-intensity-noise concept is that it is independent of any linear attenuation. A simple circuit theory of intensity noise based only on energy conservation and the Nyquist formula (zero-point fluctuation) leads to expressions of the spectral densities that agree with quantum theory even for sub-Poissonian photon statistics. When the optical gain and loss are frequency independent, the circuit theory reduces to a corpuscular theory that keeps track of the time rates of change of electron and photon numbers treated as continuous variables. Consideration is given to laser diodes in which the rate of electron-photon conversion depends nonlinearly on both the carrier and photon densities. The cross-spectral density between electrical-voltage and relative photonic fluctuations is independent of internal or external optical losses. Standard rate equations are inaccurate in the case of gain compression. Very general yet simple formulas for intensity noise are applied to room-temperature GaAs laser diodes, using recently calculated optical parameters.

J. Arnaud

1992-02-01T23:59:59.000Z

306

High-brightness switchable multiwavelength remote laser in air  

SciTech Connect (OSTI)

We demonstrate a harmonic-seeded switchable multiwavelength laser in air driven by intense midinfrared femtosecond laser pulses, in which population inversion occurs at an ultrafast time scale (i.e., less than {approx}200 fs) owing to direct formation of excited molecular nitrogen ions by strong-field ionization of inner-valence electrons. The bright multiwavelength laser in air opens the perspective for remote detection of multiple pollutants based on nonlinear optical spectroscopy.

Yao Jinping; Cheng Ya; Xu Zhizhan [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Zeng Bin; Li Guihua; Chu Wei; Ni Jielei; Zhang Haisu [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate School of Chinese Academy of Sciences, Beijing 100080 (China); Xu Huailiang [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Chin, See Leang [Center for Optics, Universite Laval, Quebec City, Quebec G1V 0A6 (Canada)

2011-11-15T23:59:59.000Z

307

Control of XeF laser output by pulse injecton  

SciTech Connect (OSTI)

Injection locking is investigated as a means for control of optical pulse duration and polarization in a XeF laser. Intense short-pulse generation in the ultraviolet is achieved by injection of a low-level 1-ns optical pulse into a XeF oscillator. Control of laser output polarization by injection locking is demonstrated and studied as a function of injected signal level. Enhancement of XeF electric-discharge laser efficiency by injection pulse ''priming'' is observed.

Pacala, T.J.; Christensen, C.P.

1980-04-15T23:59:59.000Z

308

Possibility of Prolific Pair Production with High-Power Lasers  

SciTech Connect (OSTI)

Prolific electron-positron pair production is possible at laser intensities approaching 10{sup 24} W cm{sup -2} at a wavelength of 1 {mu}m. An analysis of electron trajectories and interactions at the nodes (B=0) of two counterpropagating, circularly polarized laser beams shows that a cascade of {gamma} rays and pairs develops. The geometry is generalized qualitatively to linear polarization and laser beams incident on a solid target.

Bell, A. R.; Kirk, John G. [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom) and STFC Central Laser Facility, RAL, Didcot, OX11 0QX (United Kingdom); Max-Planck-Institut fuer Kernphysik, Saupfercheckweg, 1, D-69117, Heidelberg (Germany)

2008-11-14T23:59:59.000Z

309

energy intensity | OpenEI  

Open Energy Info (EERE)

intensity intensity Dataset Summary Description Energy intensity data and documentation published by the U.S. DOE's office of Energy Efficiency and Renewable Energy (EERE). Energy intensity is defined as: amount of energy used in producing a given level of output or activity; expressed as energy per unit of output. This is the energy intensity of the the electricity sector, which is an energy consuming sector that generates electricity. Data are organized to separate electricity-only generators from combined heat and power (CHP) generators. Data is available for the period 1949 - 2004. Source EERE Date Released May 31st, 2006 (8 years ago) Date Updated Unknown Keywords Electricity Energy Consumption energy intensity fossil fuels renewable energy Data application/vnd.ms-excel icon electricity_indicators.xls (xls, 2.1 MiB)

310

Laser Controlled Area Standard Operating Procedure (SOP)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

72 72 2 Effective: Page 1 of 16 3/6/13 Subject: X26C Laser Safety Program Documentation The only official copy of this file is the one on-line in the Photon Sciences website. Before using a printed copy, verify that it is the most current version by checking the document issue date on the Photon Sciences website. 2.1/2g03e011.doc 1 (06/2009) BROOKHAVEN NATIONAL LABORATORY LASER CONTROLLED AREA STANDARD OPERATING PROCEDURE (SOP) This document defines the safety management program for the laser system(s) listed below. All American National Standard Institute (ANSI) Hazard Class 3B and 4 laser systems must be documented, reviewed, and approved through use of this form. Each system must be reviewed annually. Modify the template for this document to fit your particular circumstance.

311

Femtosecond diffractive imaging with a soft-X-ray free-electron laser  

E-Print Network [OSTI]

LETTERS Femtosecond diffractive imaging with a soft-X-ray free-electron laser HENRY N. CHAPMAN1 of this principle using the FLASH soft-X-ray free-electron laser. An intense 25 fs, 4 Ă? 1013 W cm-2 pulse by one10 . X-ray free-electron lasers (FELs) are expected to permit diffractive imaging at high

Loss, Daniel

312

Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams  

E-Print Network [OSTI]

Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams C. B. Schroeder, E of an intense laser or the space-charge force of a charged particle beam. The implications for accelerator design and the different physical mechanisms of laser-driven and beam-driven plasma acceleration

Geddes, Cameron Guy Robinson

313

AFM CHARACTERIZATION OF LASER INDUCED DAMAGE ON CDZNTE CRYSTAL SURFACES  

SciTech Connect (OSTI)

Semi-conducting CdZnTe (or CZT) crystals can be used in a variety of detector-type applications. CZT shows great promise for use as a gamma radiation spectrometer. However, its performance is adversely affected by point defects, structural and compositional heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity), secondary phases and in some cases, damage caused by external forces. One example is damage that occurs during characterization of the surface by a laser during Raman spectroscopy. Even minimal laser power can cause Te enriched areas on the surface to appear. The Raman spectra resulting from measurements at moderate intensity laser power show large increases in peak intensity that is attributed to Te. Atomic Force Microscopy (AFM) was used to characterize the extent of damage to the CZT crystal surface following exposure to the Raman laser. AFM data reveal localized surface damage in the areas exposed to the Raman laser beam. The degree of surface damage to the crystal is dependent on the laser power, with the most observable damage occurring at high laser power. Moreover, intensity increases in the Te peaks of the Raman spectra are observed even at low laser power with little to no visible damage observed by AFM. AFM results also suggest that exposure to the same amount of laser power yields different amounts of surface damage depending on whether the exposed surface is the Te terminating face or the Cd terminating face of CZT.

Hawkins, S; Lucile Teague, L; Martine Duff, M; Eliel Villa-Aleman, E

2008-06-10T23:59:59.000Z

314

Metal reflectivity under high?intensity optical radiation  

Science Journals Connector (OSTI)

Single high?intensity (106?109 W/cm2) pulses of 1.06?? radiation emitted from a Q?switched Nd : YAG laser have been used to study reflectivity behavior of single?crystal copper and tantalum samples. Metalreflectivity during irradiation undergoes a significant drop to values much lower than can be attributed to high?temperature effects. This reflectivity drop under high radiation intensity has two characteristic features. First if vaporization is avoided then during the rising portion of the laser pulse the reflectivity drops continuously until it reaches a constant low value. For copper this occurs at an intensity of 3×108 W/cm2 and has a reflectivity value of ?0.64. The corresponding values for tantalum are I?2.5×107 W/cm2 and R?0.41. For still higher intensities a further drop in reflectivity beyond the plateau region is observed. This drop in reflectivity is always accompanied by heavy melting and followed by some vaporization. As suggested by Prokhorov e t a l. this further drop in reflectivity could be associated with dielectriclike behavior of the molten zone.

T. E. Zavecz; M. A. Saifi; M. Notis

1975-01-01T23:59:59.000Z

315

CO2 laser frequency multiplication  

SciTech Connect (OSTI)

The duration of the mode-locked CO(2) laser pulses was measured to be 0.9 + or - nsec by the technique of (second harmonic) autocorrelation. Knowing the pulse duration, the spot size, and the harmonic conversion efficiency, a detailed fit of experiment to theory gave an estimate of the nonlinear coefficient of AgGaSe(2). d36 = 31 + or - V(1), in agreement with the most accurate literature values. A number of experiments were made with longer pulse trains in which the highest harmonic energy conversion reached 78%. The damage threshold was measured and it turned out to be related much more strongly to fluence than intensity. The shorter pulse trains had peak intensities of close to 300 MW 1/cm squared whereas the longer trains (3 usec) had intensities up to 40 MW 1/cm squared.

Not Available

1992-03-01T23:59:59.000Z

316

Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced plasmas  

SciTech Connect (OSTI)

We investigated the effects of laser excitation wavelength on water-window emission lines of laser-produced boron-nitride plasmas. Plasmas are produced by focusing 1064 nm and harmonically generated 532 and 266 nm radiation from a Nd:YAG laser on BN target in vacuum. Soft x-ray emission lines in the water-window region are recorded using a grazing-incidence spectrograph. Filtered photodiodes are used to obtain complementary data for water-window emission intensity and angular dependence. Spectral emission intensity changes in nitrogen Ly-{alpha} and He-{alpha} are used to show how laser wavelength affects emission. Our results show that the relative intensity of spectral lines is laser wavelength dependent, with the ratio of Ly-{alpha} to He-{alpha} emission intensity decreasing as laser wavelength is shortened. Filtered photodiode measurements of angular dependence showed that 266 and 532 nm laser wavelengths produce uniform emission.

Crank, M.; Harilal, S. S.; Hassan, S. M.; Hassanein, A. [Center for Materials Under Extreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

2012-02-01T23:59:59.000Z

317

Accelerators for Intensity Frontier Research  

SciTech Connect (OSTI)

In 2008, the Particle Physics Project Prioritization Panel identified three frontiers for research in high energy physics, the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. In this paper, I will describe how Fermilab is configuring and upgrading the accelerator complex, prior to the development of Project X, in support of the Intensity Frontier.

Derwent, Paul; /Fermilab

2012-05-11T23:59:59.000Z

318

Ponderomotive self-focusing of Gaussian laser beam in warm collisional plasma  

SciTech Connect (OSTI)

The propagation characteristics of a Gaussian laser beam through warm collisional plasma are investigated by considering the ponderomotive force nonlinearity and the complex eikonal function. By introducing the dielectric permittivity of warm unmagnetized plasma and using the WKB and paraxial ray approximations, the coupled differential equations defining the variations of laser beam parameters are obtained and solved numerically. Effects of laser and plasma parameters such as the collision frequency, the initial laser intensity and its spot size on the beam width parameter and the axis laser intensity distribution are analyzed. It is shown that, self-focusing of the laser beam takes place faster by increasing the collision frequency and initial laser spot size and then after some distance propagation the laser beam abruptly loses its initial diameter and vastly diverges. Furthermore, the modified electron density distribution is obtained and the collision frequency effect on this distribution is studied.

Jafari Milani, M. R., E-mail: mrj.milani@gmail.com [Plasma Physics Research School, Tehran (Iran, Islamic Republic of); Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Niknam, A. R., E-mail: a-niknam@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of); Farahbod, A. H. [Plasma Physics Research School, Tehran (Iran, Islamic Republic of)

2014-06-15T23:59:59.000Z

319

Control of focusing fields in laser-plasma accelerators using higher-order modes E. Cormier-Michel,1,* E. Esarey,1  

E-Print Network [OSTI]

of intense laser pulses in plasma channels [1] has many applications, including x-ray lasers [2], highControl of focusing fields in laser-plasma accelerators using higher-order modes E. Cormier-order laser modes are analyzed as a method to control focusing forces and improve the electron bunch quality

Geddes, Cameron Guy Robinson

320

Peter A. Norreys Professor of Inertial Fusion Science,  

E-Print Network [OSTI]

Campaign · "Science of Ignition on the NIF" Workshop · Central Laser Facility / ORION #12;Universities experimental checks #12;$4 Billion US National Ignition Facility 2009 Laser system completed 2010 National Leader Central Laser Facility, Rutherford Appleton Laboratory Inertial Fusion Plasmas #12;Thanks

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Range imaging laser radar  

DOE Patents [OSTI]

A laser source is operated continuously and modulated periodically (typicy sinusoidally). A receiver imposes another periodic modulation on the received optical signal, the modulated signal being detected by an array of detectors of the integrating type. Range to the target determined by measuring the phase shift of the intensity modulation on the received optical beam relative to a reference. The receiver comprises a photoemitter for converting the reflected, periodically modulated, return beam to an accordingly modulated electron stream. The electron stream is modulated by a local demodulation signal source and subsequently converted back to a photon stream by a detector. A charge coupled device (CCD) array then averages and samples the photon stream to provide an electrical signal in accordance with the photon stream.

Scott, Marion W. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

322

A Theory of Laser Induced Nuclear Reaction in Single Atoms  

SciTech Connect (OSTI)

An 'electron-bridge' mechanism of nuclear reaction in an atom or ion by ultra-intense laser fields is presented. A preliminary estimate of the intensity dependence of the rate of disintegration reaction of deuteron nucleus in deuterium atom is made for 800 nm laser fields. For intensities below 5x10{sup 21} W/cm{sup 2}, the rate of disintegration by the 'electron-bridge' mechanism is found to be small, but it rises sharply and becomes large already for {approx_equal}10{sup 22} W/cm{sup 2}.

Faisal, F. H. M.; Donner, C. [Fakultaet fuer Physik, Universitaet Bielefeld, Postfach 100131, D-33501 Bielefeld (Germany)

2010-02-02T23:59:59.000Z

323

ITP Energy Intensive Processes: Energy-Intensive Processes Portfolio...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

teChnologIes Program IntroduCtIon the research and development (r&d) portfolio for energy-Intensive Processes (eIP) addresses the top technology opportunities to save energy...

324

Assessment of intensive silvicultural practices and livestock grazing on watershed parameters, Kisatchie National Forest, Louisiana  

E-Print Network [OSTI]

ASSESSMENT OF INTENSIVE SILVICULTURAL PRACTICES AND LIVESTOCK GRAZING ON WATERSHED PARAMETERS, KISATCHIE NATIONAL FOREST, LOUISIANA A Thesis by THOMAS KENNETH HUNTER JR. Submitted to the Graduate College of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1985 Major Subject: Range Science ASSESSMENT OF INTENSIVE SILVICULTURAL PRACTICES AND LIVESTOCK GRAZING ON WATERSHED PARAMETERS, KISATCHIE NATIONAL FOREST, LOUISIANA A Thesis...

Hunter, Thomas Kenneth

1985-01-01T23:59:59.000Z

325

Luminescent light source for laser pumping and laser system containing same  

DOE Patents [OSTI]

The invention relates to a pumping lamp for use with lasers comprising a porous substrate loaded with a component capable of emitting light upon interaction of the component with exciting radiation and a source of exciting radiation. Preferably, the pumping lamp comprises a source of exciting radiation, such as an electron beam, and an aerogel or xerogel substrate loaded with a component capable of interacting with the exciting radiation, e.g., a phosphor, to produce light, e.g., visible light, of a suitable band width and of a sufficient intensity to generate a laser beam from a laser material.

Hamil, Roy A. (Tijeras, NM); Ashley, Carol S. (Albuquerque, NM); Brinker, C. Jeffrey (Albuquerque, NM); Reed, Scott (Albuquerque, NM); Walko, Robert J. (Albuquerque, NM)

1994-01-01T23:59:59.000Z

326

Resonantly photo-pumped nickel-like erbium X-ray laser  

DOE Patents [OSTI]

A resonantly photo-pumped X-ray laser (10) that enhances the gain of seve laser lines that also lase because of collisional excitations and recombination processes, is described. The laser comprises an aluminum (12) and erbium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like erbium ions (34) are resonantly photo-pumped by line emission from hydrogen-like aluminum ions (32).

Nilsen, Joseph (Livermore, CA)

1990-01-01T23:59:59.000Z

327

Neutral particle beam intensity controller  

DOE Patents [OSTI]

The neutral beam intensity controller is based on selected magnetic defocusing of the ion beam prior to neutralization. The defocused portion of the beam is dumped onto a beam dump disposed perpendicular to the beam axis. Selective defocusing is accomplished by means of a magnetic field generator disposed about the neutralizer so that the field is transverse to the beam axis. The magnetic field intensity is varied to provide the selected partial beam defocusing of the ions prior to neutralization. The desired focused neutral beam portion passes along the beam path through a defining aperture in the beam dump, thereby controlling the desired fraction of neutral particles transmitted to a utilization device without altering the kinetic energy level of the desired neutral particle fraction. By proper selection of the magnetic field intensity, virtually zero through 100% intensity control of the neutral beam is achieved.

Dagenhart, W.K.

1984-05-29T23:59:59.000Z

328

PERI Auto-tuning Memory Intensive Kernels  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

PERI PERI - Auto-tuning Memory Intensive Kernels for Multicore Samuel Williams † , Kaushik Datta † , Jonathan Carter , Leonid Oliker † , John Shalf , Katherine Yelick † , David Bailey CRD/NERSC, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA † Computer Science Division, University of California at Berkeley, Berkeley, CA 94720, USA E-mail: SWWilliams@lbl.gov, kdatta@eecs.berkeley.edu, JTCarter@lbl.gov, LOliker@lbl.gov, JShalf@lbl.gov, KAYelick@lbl.gov, DHBailey@lbl.gov Abstract. We present an auto-tuning approach to optimize application performance on emerging multicore architectures. The methodology extends the idea of search-based performance optimizations, popular in linear algebra and FFT libraries, to application-specific computational kernels. Our work applies this strategy to Sparse Matrix Vector Multiplication

329

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1995-10-17T23:59:59.000Z

330

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1994-08-16T23:59:59.000Z

331

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

Thacker, Louis H. (Knoxville, TN)

1995-01-01T23:59:59.000Z

332

Gamma radiation field intensity meter  

DOE Patents [OSTI]

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

Thacker, Louis H. (Knoxville, TN)

1994-01-01T23:59:59.000Z

333

Gas lasers with wave-chaotic resonators  

E-Print Network [OSTI]

Semiclassical multimode laser theory is extended to gas lasers with open two-dimensional resonators of arbitrary shape. The Doppler frequency shift of the linear-gain coefficient leads to an additional linear coupling between the modes, which, however, is shown to be negligible. The nonlinear laser equations simplify in the special case of wave-chaotic resonators. In the single-mode regime, the intensity of a chaotic laser, as a function of the mode frequency, displays a local minimum at the frequency of the atomic transition. The width of the minimum scales with the inhomogeneous linewidth, in contrast to the Lamb dip in uniaxial resonators whose width is given by the homogeneous linewidth.

Oleg Zaitsev

2010-10-28T23:59:59.000Z

334

Data-intensive computing laying foundation for biological breakthroughs  

SciTech Connect (OSTI)

Finding a different way is the goal of the Data-Intensive Computing for Complex Biological Systems (Biopilot) project—a joint research effort between the Pacific Northwest National Laboratory (PNNL) and Oak Ridge National Laboratory funded by the U.S. Department of Energy’s Office of Advanced Scientific Computing Research. The two national laboratories, both of whom are world leaders in computing and computational sciences, are teaming to support areas of biological research in urgent need of data-intensive computing capabilities.

Hachigian, David J.

2007-06-18T23:59:59.000Z

335

Jupiter Laser Facility  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Jupiter Laser Facility The commissioning of the Titan Petawatt-Class laser to LLNL's Jupiter Laser Facility (JLF) has provided a unique platform for the use of petawatt (PW)-class...

336

Hypersonic gasdynamic laser system  

SciTech Connect (OSTI)

This patent describes a visible, or near to mid infra-red, hypersonic gas dynamic laser system. It comprises: a hypersonic vehicle for carrying the hypersonic gas dynamic laser system, and also providing high energy ram air for thermodynamic excitation and supply of the laser gas; a laser cavity defined within the hypersonic vehicle and having a laser cavity inlet for the laser cavity formed by an opening in the hypersonic vehicle, such that ram air directed through the laser cavity opening supports gas dynamic lasing operations at wavelengths less than 10.6{mu} meters in the laser cavity; and an optical train for collecting the laser radiation from the laser cavity and directing it as a substantially collimated laser beam to an output aperture defined by an opening in the hypersonic vehicle to allow the laser beam to be directed against a target.

Foreman, K.M.; Maciulaitis, A.

1990-05-22T23:59:59.000Z

337

Terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

...Michael Pepper Terahertz quantum cascade lasers Jerome Faist 1 Lassaad Ajili...developments in terahertz quantum cascade lasers are reviewed. Structures...magnetic confinement| Terahertz quantum cascade lasers. | Recent developments in...

2004-01-01T23:59:59.000Z

338

PT-Symmetric Phonon Laser  

E-Print Network [OSTI]

By exploiting recent developments associated with coupled microcavities, we introduce the concept of PT-symmetric phonon laser with balanced gain and loss. This is accomplished by introducing gain to one of the microcavities such that it balances the passive loss of the other. In the vicinity of the gain-loss balance, a strong nonlinear relation emerges between the intracavity photon intensity and the input power. This then leads to a giant enhancement of both optical pressure and mechanical gain, resulting in a highly efficient phonon-lasing action. These results provide a promising approach for manipulating optomechanical systems through PT-symmetric concepts. Potential applications range from enhancing mechanical cooling to designing phonon-laser amplifiers.

H. Jing; Sahin K. Ozdemir; Xin-You Lv; Jing Zhang; Lan Yang; Franco Nori

2014-03-04T23:59:59.000Z

339

LASER-ELECTRON COMPTON INTERACTION IN PLASMA CHANNELS  

SciTech Connect (OSTI)

A concept of high intensity femtosecond laser synchrotron source (LSS) is based on Compton backscattering of focused electron and laser beams. The short Rayleigh length of the focused laser beam limits the length of interaction to a few picoseconds. However, the technology of the high repetition rate high-average power picosecond lasers required for high put through LSS applications is not developed yet. Another problem associated with the picosecond laser pulses is undesirable nonlinear effects occurring when the laser photons are concentrated in a short time interval. To avoid the nonlinear Compton scattering, the laser beam has to be split, and the required hard radiation flux is accumulated over a number of consecutive interactions that complicates the LSS design. In order to relieve the technological constraints and achieve a practically feasible high-power laser synchrotron source, we propose to confine the laser-electron interaction region in the extended plasma channel. This approach permits to use nanosecond laser pulses instead of the picosecond pulses. That helps to avoid the nonlinear Compton scattering regime and allows to utilize already existing technology of the high-repetition rate TEA CO{sub 2} lasers operating at the atmospheric pressure. We demonstrate the advantages of the channeled LSS approach by the example of the prospective polarized positron source for Japan Linear Collider.

POGORELSKY,I.V.

1998-10-01T23:59:59.000Z

340

High Power Lasers... Another approach to  

E-Print Network [OSTI]

as an integrated system Simultaneously addressing the science and engineering Direct Drive Pellet Designs Computer and technologies together, using the end goal of a practical power source as a guide Lasers DPPSL (LLNL) KrF (NRL) Target Fabrication Target Injection Chamber/Materials Final Optics Target Design (+NRL & LLE ) #12

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Theoretical Physics | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier Cosmic Frontier Theoretical Physics Unique Aspects and...

342

Research | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Research High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier Cosmic Frontier Theoretical Physics Advanced...

343

Cosmic Frontier | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Cosmic Frontier High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier Cosmic Frontier Theoretical Physics...

344

Energy Frontier | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Energy Frontier High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier Cosmic Frontier Theoretical Physics...

345

Production of a keV X-Ray Beam from Synchrotron Radiation in Relativistic Laser-Plasma Interaction  

E-Print Network [OSTI]

Production of a keV X-Ray Beam from Synchrotron Radiation in Relativistic Laser-Plasma Interaction demonstrate that a beam of x-ray radiation can be generated by simply focusing a single high- intensity laser spectral range) [6]. Laser-driven K x-ray sources [7­9] radiate subnanometer wavelength radiation

Umstadter, Donald

346

Laser Desorption Analysis | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Desorption Analysis Laser Desorption Analysis EMSL offers a suite of instrumentation dedicated to understanding photoreactivity in the condensed phase, on surfaces, and at...

347

Laser Desorption Analysis | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

neutral particle detection using a second multiphoton ionization or REMPI laser system; and UHV surface diagnostic equipment (AES, LEED, XPS). User Portal Name: Laser...

348

Laser Safety Management Policy Statement ............................................................................................................1  

E-Print Network [OSTI]

Laser Safety Management Policy Statement...........................................................2 Laser Users.............................................................................................................2 Unit Laser Safety Officer (ULSO

Davidson, Fordyce A.

349

Matrix-assisted Laser Desorption/Ionization by Two Collinear Subthreshold Laser Pulses  

E-Print Network [OSTI]

laser pulse delay times yielding maximum guest ion intensities were determined for four different (e.g. ~ 1140 m/s for sinapinic acid (SA) ions4 ), mass-independent guest velocities point to jet and molecular dynamics calcula- tions7 indicate similar lift-off velocities for neutrals and the possible role

Vertes, Akos

350

Double pulse laser induced breakdown spectroscopy; experimental study of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Double pulse laser induced breakdown spectroscopy; experimental study of Double pulse laser induced breakdown spectroscopy; experimental study of lead emission intensity dependence on the wavelengths and sample matrix Title Double pulse laser induced breakdown spectroscopy; experimental study of lead emission intensity dependence on the wavelengths and sample matrix Publication Type Journal Article Year of Publication 2009 Authors Piscitelli, Vincent, Mauro A. Martinez, Alberto J. Fernandez, Jhanis J. Gonzalez, Xianglei Mao, and Richard E. Russo Journal Spectrochimica Acta Part B Volume 64 Issue 2 Pagination 147-154 Date Published 02/2009 Keywords Double pulse LIBS, laser induced breakdown spectroscopy, lead Abstract Lead (Pb) emission intensity (atomic line 405.78 nm) dependence on the sample matrix (metal alloy) was studied by means of collinear double pulse (DP)-laser induced breakdown spectroscopy (LIBS). The measurement of the emission intensity produced by three different wavelength combinations (i.e. I:532 nm-II:1064 nm, I:532 nm-II:532 nm, and I:532 nm-II:355 nm) from three series of standard reference materials showed that the lead atomic line 405.78 nm emission intensity was dependent on the sample matrix for all the combination of wavelengths, however reduced dependency was found for the wavelength combination I:532 nm-II:355 nm.

351

Laser Stabilization  

SciTech Connect (OSTI)

This book chapter covers the basics of the field of stabilizing lasers to optical frequency references such as optical cavities and molecular transitions via the application of servo control systems. These discussions are given with reference to the real-life frequency metrology experienced in Hall-Labs (now Ye-Labs), JILA, University of Colorado. The subjects covered include: the basics of control system stability, a discussion of both the theoretical and experimental limitations, an outline of optical cavity susceptibility to environmental noise, and a brief introduction to the use and limitations of molecular transitions as frequency references.

Hall, John L.; Taubman, Matthew S.; Ye, Jun

2010-01-01T23:59:59.000Z

352

Omega Laser Facility - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

- Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to LLE LLE Tours LLE...

353

OMEGA Laser - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

- Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to LLE LLE Tours LLE...

354

OMEGA Laser Drivers - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Drivers - Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to LLE LLE...

355

Waves in Nature, Lasers to Tsumanis and Beyond  

ScienceCinema (OSTI)

Waves are everywhere. Microwaves, laser beams, music, tsunamis. Electromagnetic waves emanating from the Big Bang fill the universe. Learn about the similarities and difference in all of these wavy phenomena with Ed Moses and Rick Sawicki, Lawrence Livermore National Laboratory scientists Series: Science on Saturday [10/2006] [Science] [Show ID: 11541

LLNL - University of California Television

2009-09-01T23:59:59.000Z

356

MICROCAVITYMICROCAVITY PLASMA SCIENCE AND RECENTPLASMA SCIENCE AND RECENT APPLICATIONS: BOUNDAPPLICATIONS: BOUND--FREE COUPLING, TRANSISTORFREE COUPLING, TRANSISTOR  

E-Print Network [OSTI]

Plasma Surface Treatment High Intensity Plasma Arc Lamp Spark Gap Plasma Display (150 inch Panasonic Electrode Glass6 mm 250 m LED Backlight Microcavity Lamp #12;OPERATION OF MICROCAVITY PLASMA DEVICESMICROCAVITYMICROCAVITY PLASMA SCIENCE AND RECENTPLASMA SCIENCE AND RECENT APPLICATIONS

Shyy, Wei

357

Environmental Design for Patient Families in Intensive Care Unites  

E-Print Network [OSTI]

Open Access to this article benefits you. 2010 Multi-Science Publishing ISSN 1756-8250 Environmental Design for Patient Families in Intensive Care Units by Mahbub Rashid Reprinted from Journal of Healthcare Engineering Vol. 1 · No. 3 · 2010 Journal... wayfinding systems can be extremely costly piecemeal. The ED of a well-integrated in terms of both patient and family wayfinding system should include satisfaction and hard dollars. external building cues, functional • People tend to move along routes...

Rashid, Mahbub

2010-01-01T23:59:59.000Z

358

Changes in Energy Intensity 1985-1991  

Gasoline and Diesel Fuel Update (EIA)

Changes in Energy Intensity Changes in Energy Intensity 1985-1991 Overview Full Report The focus is on intensity of energy use measured by energy consumption relative to constant...

359

The laser satellites communications and laser noises  

Science Journals Connector (OSTI)

The gain of advanced optical communication systems is reduced by the noise of optical source. Coherent optical communication systems are in particular very sensitive to the noise transmitter and local laser. Optical space communications is on the verge ... Keywords: laser, laser communication, noise limits, optical communication, range loss, satellite communications, satellite systems, signal transfer loss, space channel

Marketa Mazalkova

2008-08-01T23:59:59.000Z

360

Render four channel data sets and allow real-time changes of colors and intensities.  

E-Print Network [OSTI]

University who work with images from confocal laser scanning microscopes (CLSM). · CLSM generate stacks of images (z-stacks) from specimen that had been stained with up to four different fluorescent proteins Table 1. · By using maximum intensity projection (MIP) we do not need to calculate opacity: multi

Schulze, JĂĽrgen P.

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Photon Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Photon Science Along with its primary missions-global security, energy security, basic science, and national competitiveness-the NIF & Photon Science Directorate also pursues...

362

Science Engagement  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Science Engagement Science Engagement Move your data Programs & Workshops Science Requirements Reviews Case Studies Contact Us Technical Assistance: 1 800-33-ESnet (Inside US) 1...

363

Science Briefs  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Science Briefs newsroomassetsimagesnewsroom-icon.jpg Science Briefs Read in detail about specific Los Alamos science achievements, and the honors our scientists are accruing....

364

Detection Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Chemistry for Measurement and Detection Science Chemistry for Measurement and Detection Science Project Description Chemistry used in measurement and detection science plays a...

365

Ultrafast Materials and Chemical Sciences FOA | U.S. DOE Office...  

Office of Science (SC) Website

manipulation of highly correlated electron systems in condensed matter Free electron laser science to investigate time-resolved phenomena correlated electron excitations and...

366

John L. Emmett, 1977 | U.S. DOE Office of Science (SC)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

as an effective leader, which have been central to the development of laser science and technology and to their application to the generation of nuclear and thermonuclear energy...

367

Zigzag laser with reduced optical distortion  

DOE Patents [OSTI]

The architecture of the present invention has been driven by the need to solve the beam quality problems inherent in Brewster's angle tipped slab lasers. The entrance and exit faces of a solid state slab laser are cut perpendicular with respect to the pump face, thus intrinsically eliminating distortion caused by the unpumped Brewster's angled faces. For a given zigzag angle, the residual distortions inherent in the remaining unpumped or lightly pumped ends may be reduced further by tailoring the pump intensity at these ends. 11 figures.

Albrecht, G.F.; Comaskey, B.; Sutton, S.B.

1994-04-19T23:59:59.000Z

368

Zigzag laser with reduced optical distortion  

DOE Patents [OSTI]

The architecture of the present invention has been driven by the need to solve the beam quality problems inherent in Brewster's angle tipped slab lasers. The entrance and exit faces of a solid state slab laser are cut perpendicular with respect to the pump face, thus intrinsically eliminating distortion caused by the unpumped Brewster's angled faces. For a given zigzag angle, the residual distortions inherent in the remaining unpumped or lightly pumped ends may be reduced further by tailoring the pump intensity at these ends.

Albrecht, Georg F. (Livermore, CA); Comaskey, Brian (Stockton, CA); Sutton, Steven B. (Manteca, CA)

1994-01-01T23:59:59.000Z

369

Future STEM Leaders Prepare for the National Science Bowl  

SciTech Connect (OSTI)

Each year, students from across the country converge on Washington, DC, for the National Science Bowl, an intense academic competition that tests the students' knowledge in science, engineering, chemistry, math and Earth science. Follow one team, from Washington DC's Woodrow Wilson High School, as they prepare for and compete in the 2014 National Science Bowl.

Benjamin, Angela

2014-06-11T23:59:59.000Z

370

Future STEM Leaders Prepare for the National Science Bowl  

ScienceCinema (OSTI)

Each year, students from across the country converge on Washington, DC, for the National Science Bowl, an intense academic competition that tests the students' knowledge in science, engineering, chemistry, math and Earth science. Follow one team, from Washington DC's Woodrow Wilson High School, as they prepare for and compete in the 2014 National Science Bowl.

Benjamin, Angela

2014-09-15T23:59:59.000Z

371

Intensive Skills Activities CAREERS SERVICE  

E-Print Network [OSTI]

in the state under the cover of night and in broad daylight, perhaps swimming in ship ballast water, tucked and the rest of the world focus more intensely on producing fuels and energy from grasses and other non to subscribe (it's free!), send a note to Futures Editor, 109 Agriculture Hall, Michigan State University, East

Bristol, University of

372

Neutral particle beam intensity controller  

DOE Patents [OSTI]

A neutral beam intensity controller is provided for a neutral beam generator in which a neutral beam is established by accelerating ions from an ion source into a gas neutralizer. An amplitude modulated, rotating magnetic field is applied to the accelerated ion beam in the gas neutralizer to defocus the resultant neutral beam in a controlled manner to achieve intensity control of the neutral beam along the beam axis at constant beam energy. The rotating magnetic field alters the orbits of ions in the gas neutralizer before they are neutralized, thereby controlling the fraction of neutral particles transmitted out of the neutralizer along the central beam axis to a fusion device or the like. The altered path or defocused neutral particles are sprayed onto an actively cooled beam dump disposed perpendicular to the neutral beam axis and having a central open for passage of the focused beam at the central axis of the beamline. Virtually zero therough 100% intensity control is achieved by varying the magnetic field strength without altering the ion source beam intensity or its species yield.

Dagenhart, William K. (Oak Ridge, TN)

1986-01-01T23:59:59.000Z

373

NREL: Energy Sciences - Materials Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Materials Science Hydrogen Technology & Fuel Cells Process Technology & Advanced Concepts Research Staff Computational Science Printable Version Materials Science Learn about our...

374

ablation laser spectrometer  

E-Print Network [OSTI]

ablation laser mass spectrometer molecular beam REMPI laser NREL has designed and developed a combined laser ablation/ pulsed sample introduction/mass spectrometry platform that integrates pyrolysis and/or laser ablation with resonance- enhanced multiphoton ionization (REMPI) time-of-flight mass

375

Narrow gap laser welding  

DOE Patents [OSTI]

A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables. 34 figs.

Milewski, J.O.; Sklar, E.

1998-06-02T23:59:59.000Z

376

Narrow gap laser welding  

DOE Patents [OSTI]

A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables.

Milewski, John O. (Santa Fe, NM); Sklar, Edward (Santa Fe, NM)

1998-01-01T23:59:59.000Z

377

Short wavelength laser  

DOE Patents [OSTI]

A short wavelength laser is provided that is driven by conventional-laser pulses. A multiplicity of panels, mounted on substrates, are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path. When the panels are illuminated by the conventional-laser pulses, single pass EUV or soft x-ray laser pulses are produced.

Hagelstein, P.L.

1984-06-25T23:59:59.000Z

378

Center for Cell and Genome Sciences, Crocker Science Building  

E-Print Network [OSTI]

chemistry Center for Cell and Genome Sciences genetic engineering building artificial life brain engineering nanotechnology light generating molecules light-activated ion channels breaking the light barrier laser tweezers photodiodes #12;the Cell engineering the genome, imaging proteins Invitrogen at the intersection of chemistry

Tipple, Brett

379

Demonstration of Laser Induced X-Ray Generation in an Expanding Laser Produced Plasma  

Science Journals Connector (OSTI)

X-ray emission at 10 nm stimulated by visible laser radiation at 614.2 nm in a beryllium laser produced plasma was investigated. A method of laser induced quenching of metastable ions was applied to He-like Be2+ ions in the 1s2s 1S0 state. Laser excitation to the 1s2p 1P1 state was followed by an intense x-ray emission at a resonance 1s2 1S0-1s2p 1P1 transition. Time, angular, and polarization characteristics of the radiation were studied; a linear polarization and a dipole type angular distribution have been found. The total energy radiated in a 1.5 ns pulse amounted to 10 ?J.

D. M. Simanovskii, A. N. Gladskikh, L. A. Shmaenok, and S. V. Bobashev

1996-07-29T23:59:59.000Z

380

Laser Glazing of Railroad Rails [Laser Applications Laboratory] - Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Glazing of Railroad Laser Glazing of Railroad Rails Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Glazing of Railroad Rails Project description: Laser glazing of rails. Category: Project with industrial partner (American Association of Railroads) Bookmark and Share

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Laser Welding of Metals [Laser Applications Laboratory] - Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Welding of Metals Laser Welding of Metals Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Welding of Metals Project description: High-speed laser welding of metals. Category: Project with industrial partner (Delphi Energy and Engine Management Systems) Bookmark and Share

382

Science Mathematics Engineering  

E-Print Network [OSTI]

Science Mathematics Engineering . ­ p.1 #12;Science Mathematics Engineering Science, Computer `Science', . ­ p.1 #12;Science Mathematics Engineering Science, Computer `Science', Mathematics, . ­ p.1 #12;Science Mathematics Engineering Science, Computer `Science', Mathematics, and Software Development

Hamlet, Richard

383

Effects of carbon nanotubes and graphene oxide absorbers on the noise of mode-locked fiber lasers  

E-Print Network [OSTI]

Phase noise is very important for the ultrafast pulse application in telecommunication, ultrafast diagnose, material science, and biology. In this paper, two types of carbon nano-materials, single-wall carbon nanotube and graphene oxide, are investigated for noise suppression in ultrafast photonics. Various properties of the wall-paper SAs, such as saturable intensity, optical absorption and degree of purity, are found to be key factors determining the phase noise of the ultrafast pulses. A reduced-noise femtosecond fiber laser is experimentally demonstrated by optimizing the above parameters of carbon material based SAs. The phase noise reduction more than 10 dB at 10 kHz can be obtained in the experiments. To our knowledge, this is the first time that the relationship between different carbon material based SAs and the phase noise of mode-locked lasers has been investigated. This work will pave the way to get a high-quality ultrashort pulse in passively mode-locked fiber lasers.

Li, Xiaohui; Yu, Xuechao; Wang, Yonggang; Wang, Yishan; Meng, Bo; Tang, Yulong; Yu, Xia; Zhang, Ying; Sun, Zhipei; Shum, Perry Ping; Wang, Qi Jie

2014-01-01T23:59:59.000Z

384

Advances in materials science, metals and ceramics division. Triannual progress report, June-September 1980  

SciTech Connect (OSTI)

Information is presented concerning the magnetic fusion energy program; the laser fusion energy program; geothermal research; nuclear waste management; Office of Basic Energy Sciences (OBES) research; diffusion in silicate minerals; chemistry research resources; and chemistry and materials science research.

Truhan, J.J.; Hopper, R.W.; Gordon, K.M. (eds.)

1980-10-28T23:59:59.000Z

385

Advances in materials science, Metals and Ceramics Division. Triannual progress report, February-May 1980  

SciTech Connect (OSTI)

Research is reported in the magnetic fusion energy and laser fusion energy programs, aluminium-air battery and vehicle research, geothermal research, nuclear waste management, basic energy science, and chemistry and materials science. (FS)

Truhan, J.J.; Gordon, K.M. (eds.)

1980-08-01T23:59:59.000Z

386

Copyright 2006 by the NEPAD Office of Science and Technology  

E-Print Network [OSTI]

#12;Copyright © 2006 by the NEPAD Office of Science and Technology P.O. Box 395, Lynnwood, Pretoria Office of Science and Technology. Publication compiled by Dr. John Mugabe and Professor Aggrey Ambali 24 PROGRAMME CLUSTER 3: MATERIAL SCIENCES, MANUFACTURING, LASER AND POST-HARVEST TECHNOLOGIES 33

387

Growing Crystaline Sapphire Fibers By Laser Heated Pedestal Techiques  

DOE Patents [OSTI]

An improved system and process for growing crystal fibers comprising a means for creating a laser beam having a substantially constant intensity profile through its cross sectional area, means for directing the laser beam at a portion of solid feed material located within a fiber growth chamber to form molten feed material, means to support a seed fiber above the molten feed material, means to translate the seed fiber towards and away from the molten feed material so that the seed fiber can make contact with the molten feed material, fuse to the molten feed material and then be withdrawn away from the molten feed material whereby the molten feed material is drawn off in the form of a crystal fiber. The means for creating a laser beam having a substantially constant intensity profile through its cross sectional area includes transforming a previously generated laser beam having a conventional gaussian intensity profile through its cross sectional area into a laser beam having a substantially constant intensity profile through its cross sectional area by passing the previously generated laser beam through a graded reflectivity mirror. The means for directing the laser beam at a portion of solid feed material is configured to direct the laser beam at a target zone which contains the molten feed material and a portion of crystal fiber drawn off the molten feed material by the seed fiber. The means to support the seed fiber above the molten feed material is positioned at a predetermined height above the molten feed material. This predetermined height provides the seed fiber with sufficient length and sufficient resiliency so that surface tension in the molten feed material can move the seed fiber to the center of the molten feed material irrespective of where the seed fiber makes contact with the molten feed material. The internal atmosphere of the fiber growth chamber is composed substantially of Helium gas.

Phomsakha, Vongvilay (St. Petersburg, FL); Chang, Robert S. F. (Tampa, FL); Djeu, Nicholas I. (Tampa, FL)

1997-03-04T23:59:59.000Z

388

Capabilities Strategy: Science Pillars  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Innovation Capabilities Strategy: Science Pillars science-innovationassetsimagesicon-science.jpg Capabilities Strategy: Science Pillars The Lab's four Science Pillars...

389

Science Fairs for Science Literacy  

E-Print Network [OSTI]

is supported by a National Science Foundation PostdoctoralT.  Culbertson is a middle school science and math teacher.for the Advancement of Science (AAAS) (1990), Science for

Mackey, Katherine; Culbertson, Timothy

2014-01-01T23:59:59.000Z

390

BIOLOGICAL SCIENCES Contemporary biological science  

E-Print Network [OSTI]

BIOLOGICAL SCIENCES Contemporary biological science covers a range of diverse and overlapping in cellular and molecular biology. Wichita State University's Department of Biological Sciences offers courses in most aspects of contemporary biological science. Our required core courses will expose you

391

PALM - Laser Capture Microdissection | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

PALM - Laser Capture Microdissection PALM - Laser Capture Microdissection This Laser Capture Microdissection system is equipped with 100 x objective lens for enriching distinct...

392

Neutrino physics with an intense \  

E-Print Network [OSTI]

We study some of the physics potential of an intense $1\\,\\mathrm{MCi}$ $^{51}\\mathrm{Cr}$ source combined with the {\\sc Majorana Demonstrator} enriched germanium detector array. The {\\sc Demonstrator} will consist of detectors with ultra-low radioactive backgrounds and extremely low energy thresholds of~$\\sim 400\\,\\mathrm{eV}$. We show that it can improve the current limit on the neutrino magnetic dipole moment. We briefly discuss physics applications of the charged-current reaction of the $^{51}\\mathrm{Cr} neutrino with the $^{73}\\mathrm{Ge} isotope. Finally, we argue that the rate from a realistic, intense tritium source is below the detectable limit of even a tonne-scale HPGe experiment

R. Henning

2010-11-16T23:59:59.000Z

393

Short-pulse laser interferometric measurement of absolute gas densities from a cooled gas jet  

Science Journals Connector (OSTI)

We report on the use of a novel technique to measure the gas density from a pulsed gas jet. Deuterium gas is fully ionized with an intense picosecond laser, and the resulting...

Ditmire, T; Smith, R A

1998-01-01T23:59:59.000Z

394

Multiple isotope magneto-optical trap from a single diode laser  

Science Journals Connector (OSTI)

We present a dual isotope magneto-optical trap produced using a single diode laser. We generate all the optical frequencies needed for trapping both species using a fiber intensity...

Valenzuela, Victor Manuel; Hamzeloui, Saeed; Gutiérrez, Monica; Gomez, Eduardo

2013-01-01T23:59:59.000Z

395

Spectroscopic studies of XeCl-laser-induced plasma on Ti targets in nitrogen containing atmospheres  

Science Journals Connector (OSTI)

This work deals with the study of a plasma produced by intense XeCl-excimer-laser irradiation of a titanium surface in nitrogen-containing atmospheres. We observed that the optical emission spectra ... from irrad...

M. L. De Giorgi; J. Hermann; A. Luches; A. Perrone; L. Renna

1994-06-01T23:59:59.000Z

396

Electron-beam–deposited distributed polarization rotator for high-power laser applications  

Science Journals Connector (OSTI)

Electron-beam deposition of silica and alumina is used to fabricate distributed polarization rotators suitable for smoothing the intensity of large-aperture, high-peak-power lasers....

Oliver, J B; Kessler, T J; Smith, C; Taylor, B; Gruschow, V; Hettrick, J; Charles, B

2014-01-01T23:59:59.000Z

397

Nonlinear Phenomena Induced by Millijoule Femtosecond Laser Pulses at an Air-water Interface  

E-Print Network [OSTI]

transformation in water. We find that nonlinear femtosecond pulse propagation begins at a peak pulse intensity of about 1010 W/cm2. This experiment provides a convenient segway into the discussion and investigation of femtosecond laser filaments. We describe...

Strycker, Benjamin

2013-11-04T23:59:59.000Z

398

The Science of Science Foundation  

Science Journals Connector (OSTI)

... THE 'science of ... of science' is an awkward name but, as it describes accurately what is meant, it ...

MAURICE GOLDSMITH

1965-01-02T23:59:59.000Z

399

Scattering apodizer for laser beams  

DOE Patents [OSTI]

A method is disclosed for apodizing a laser beam to smooth out the production of diffraction peaks due to optical discontinuities in the path of the laser beam, such method comprising introduction of a pattern of scattering elements for reducing the peak intensity in the region of such optical discontinuities, such pattern having smoothly tapering boundaries in which the distribution density of the scattering elements is tapered gradually to produce small gradients in the distribution density, such pattern of scattering elements being effective to reduce and smooth out the diffraction effects which would otherwise be produced. The apodizer pattern may be produced by selectively blasting a surface of a transparent member with fine abrasive particles to produce a multitude of minute pits. In one embodiment, a scattering apodizer pattern is employed to overcome diffraction patterns in a multiple element crystal array for harmonic conversion of a laser beam. The interstices and the supporting grid between the crystal elements are obscured by the gradually tapered apodizer pattern of scattering elements.

Summers, Mark A. (Livermore, CA); Hagen, Wilhelm F. (Livermore, CA); Boyd, Robert D. (Livermore, CA)

1985-01-01T23:59:59.000Z

400

Scattering apodizer for laser beams  

DOE Patents [OSTI]

A method is disclosed for apodizing a laser beam to smooth out the production of diffraction peaks due to optical discontinuities in the path of the laser beam, such method comprising introduction of a pattern of scattering elements for reducing the peak intensity in the region of such optical discontinuities, such pattern having smoothly tapering boundaries in which the distribution density of the scattering elements is tapered gradually to produce small gradients in the distribution density, such pattern of scattering elements being effective to reduce and smooth out the diffraction effects which would otherwise be produced. The apodizer pattern may be produced by selectively blasting a surface of a transparent member with fine abrasive particles to produce a multitude of minute pits. In one embodiment, a scattering apodizer pattern is employed to overcome diffraction patterns in a multiple element crystal array for harmonic conversion of a laser beam. The interstices and the supporting grid between the crystal elements are obscured by the gradually tapered apodizer pattern of scattering elements.

Summers, M.A.; Hagen, W.F.; Boyd, R.D.

1984-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

The effect of plasma channel on the self-distortion of laser pulse propagating through the collisional plasma channel  

Science Journals Connector (OSTI)

Abstract In the present paper, laser pulse distortion/breakup and the effect of the plasma channel on the laser propagation through the collisional plasma have been studied by using moment theory approach. Second order nonlinear differential equations of the beam width parameter have been derived for the propagation of the laser through uniform homogenous plasma and preformed plasma channel having parabolic density profile. Differential equations of beam width parameter have been solved numerically using Runge Kutta method. It has been observed from analysis that when the laser pulse propagates through the homogenous plasma, the low intensity front and rear parts of the laser get defocused/diffracted and the high intensity central/main portion of the laser pulse gets self-guided. As a result of this, the laser pulse gets distorted. This distortion of the laser has not been observed when the laser pulse is propagated through the plasma channel having density minimum at the axis and maximum at the edges. The laser pulse is guided as a whole, even the low intensity front and rear parts of the laser are also guided. Therefore, the plasma channel is useful to prevent the distortion/breakup of the laser.

Navpreet Singh; Arvinder Singh

2014-01-01T23:59:59.000Z

402

Science in science fiction  

Science Journals Connector (OSTI)

Science fiction, from Star Trek to Star Wars, is hugely popular and pupils will surely have encountered good and bad physics there, but do they really notice? Discussing the science implied in books and movies, such as in the use of transporters, can be a good way of getting students interested in physics.

Jonathan Allday

2003-01-01T23:59:59.000Z

403

Laser assisted proton collision on light nuclei at moderate energies  

E-Print Network [OSTI]

We present analytic angular differential cross section model for laser assisted proton nucleon scattering on a Woods-Saxon optical potential where the nth-order photon absorption is taken into account simultaneously. As a physical example we calculate cross sections for proton - $^{12}$C collision at 49 MeV in the laboratory frame where the laser intensity is in the range of $ 10^{7} - 10^{21}$ W/cm$^2$ at optical frequencies. The upper intensity limit is slightly below the relativistic regime.

I. F Barna; S. Varro

2014-06-24T23:59:59.000Z

404

Method for changing the cross section of a laser beam  

DOE Patents [OSTI]

A technique is disclosed herein in which a circular optical beam, for example a copper vapor laser (CVL) beam, is converted to a beam having a profile other than circular, e.g. square or triangular. This is accomplished by utilizing a single optical mirror having a reflecting surface designed in accordance with a specifically derived formula in order to make the necessary transformation, without any substantial light loss and without changing substantially the intensity profile of the circular beam which has a substantially uniform intensity profile. In this way, the output beam can be readily directed into the dye cell of a dye laser. 4 figs.

Sweatt, W.C.; Seppala, L.

1995-12-05T23:59:59.000Z

405

1 Biomedical Sciences BIOMEDICAL SCIENCES  

E-Print Network [OSTI]

1 Biomedical Sciences BIOMEDICAL SCIENCES The interdisciplinary doctoral programs in the biomedical sciences are organized within the Institute for Biomedical Sciences. The first full year of study toward are admitted directly into the Institute for Biomedical Sciences through Columbian College of Arts and Sciences

Vertes, Akos

406

DOE Center of Excellence in Medical Laser Applications. Final report  

SciTech Connect (OSTI)

An engineering network of collaborating medical laser laboratories are developing laser and optical technologies for medical diagnosis and therapy and are translating the engineering into medical centers in Portland, OR, Houston, TX, and Galveston, TX. The Center includes the University of Texas M.D. Anderson Cancer Center, the University of Texas-Austin, Texas A and M University, Rice University, the University Texas Medical Branch-Galveston, Oregon Medical Laser Center (Providence St. Vincent Medical Center, Oregon Health Sciences University, and Oregon Graduate Institute, Portland, OR), and the University of Oregon. Diagnostics include reflectance, fluorescence, Raman IR, laser photoacoustics, optical coherence tomography, and several new video techniques for spectroscopy and imaging. Therapies include photocoagulation therapy, laser welding, pulsed laser ablation, and light-activated chemotherapy of cancer (photodynamic therapy, or PDT). Medical applications reaching the clinic include optical monitoring of hyperbilirubinemia in newborns, fluorescence detection of cervical dysplasia, laser thrombolysis of blood clots in heart attack and brain stroke, photothermal coagulation of benign prostate hyperplasia, and PDT for both veterinary and human cancer. New technologies include laser optoacoustic imaging of breast tumors and hemorrhage in head trauma and brain stroke, quality control monitoring of dosimetry during PDT for esophageal and lung cancer, polarization video reflectometry of skin cancer, laser welding of artificial tissue replacements, and feedback control of laser welding.

Jacques, S.L. (Oregon Medical Laser Center, Portland, OR (United States))

1998-01-01T23:59:59.000Z

407

Photon Sciences Training Courses  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Photon Sciences Training Courses Photon Sciences Training Courses Beamline Ops (BLOSA) BNL Web Courses (Help) BNL Class Schedules Business Systems & Software Contractor Orientation Cranes, Forklifts, Aerial Lifts Electrical Environmental ESH Briefings ESH Tours GERT GERT Reciprocity Human Resources IRP (Briefings) (Procedures) Job Briefings JRAs and FRAs Lasers Lead Machine Shops Medical Surveillance Nano Materials NSLS-II (Bldg 740) Photographic Dark Rm Procedures (Control Rm) Procedures (PRMs) (SOPs) Radiological Remedial (GERT) (NSLS) Roster Form (.docx) R2A2s Source Dev Lab Staff Development Study Guides Supervisory Training Training Course Dev Form User Training Work Control All Photon Sciences (PS) courses and some BNL courses (HP, OM, TQ, and GE) commonly assigned by the PS Directorate for work within PS buildings are

408

Conservation laws and laser cooling of atoms  

E-Print Network [OSTI]

The straightforward application of energy and linear momentum conservation to the absorption/emission of photons by atoms--first outlined by Schr\\"odinger in 1922--allows to establish the essential features of laser cooling of two levels atoms at low laser intensities. The minimum attainable average kinetic energy of the atoms depends on the ratio $\\Gamma/E_R$ between the natural linewidth and the recoil energy and tends to $E_R$ as $\\Gamma/E_R$ tends to zero. This treatment is valid for any value of the ratio $\\Gamma/E_R$ and contains the semiclassical theory of laser cooling as the limiting case in which $E_R\\ll \\Gamma$.

Giuliani, Giuseppe

2015-01-01T23:59:59.000Z

409

Ion expansion characteristics from a KrF-laser-produced plasma  

Science Journals Connector (OSTI)

Two groups of ions are observed in an aluminum plasma produced by focusing a Raman-compressed KrF-laser beam (268 nm) on thick planar targets in the intensity range 5×1011–1013 W/cm2. The angular distribution, velocity distribution, energy partition between the two groups, and scaling of the ion velocities with laser intensity are presented. The role of lateral energy transport in generating the two groups of ions is discussed.

P. D. Gupta; Y. Y. Tsui; R. Popil; R. Fedosejevs; A. A. Offenberger

1986-05-01T23:59:59.000Z

410

BNL | CO2 Laser  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

CO2 Laser CO2 Laser The ATF is one of the only two facilities worldwide operating picosecond, terawatt-class CO2 lasers. Our laser system consists of a picoseconds pulse-injector based on fast optical switching from the output of a conventional CO2 laser oscillator, and a chain of high-pressure laser amplifiers. It starts with a wavelength converter wherein a near-IR picosecond solid-state laser with l»1 μm produces a mid-IR 10-μm pulse. This process employs two methods; semiconductor optical switching, and the Kerr effect. First, we combine the outputs from a multi-nanosecond CO2 laser oscillator with a picosecond Nd:YAG laser on a germanium Brewster-plate to produce an ~200 ps, 10μm pulse by semiconductor optical switching. Co-propagating this pulse with a Nd:YAG's 2nd harmonic in a

411

An Open-path Laser Transmissometer for Atmospheric Extinction Measurements  

SciTech Connect (OSTI)

A transmissometer is an optical instrument which measures transmitted intensity of monochromatic light over a fixed pathlength. Prototype of a simple laser transmissometer has been developed for transmission (or extinction) measurements through suspended absorbers and scatterers in the atmosphere over tens of meters. Instrument consists of a continuous green diode pumped solid state laser, transmission optics, photodiode detectors and A/D data acquisition components. A modulated laser beam is transmitted and subsequently reflected and returned to the unit by a retroreflecting mirror assembly placed several tens of meters away. Results from an open-path field measurement of the instrument are described.

Chandran, P. M. Satheesh; Krishnakumar, C. P.; Varma, Ravi [Department of Physics, National Institute of Technology Calicut, Calicut, Kerala 673 601 (India); Yuen, Wangki; Rood, Mark J. [Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, Urbana (United States)

2011-10-20T23:59:59.000Z

412

DFT studies of ethylene in femtosecond laser pulses  

E-Print Network [OSTI]

Using time-dependent density functional theory, applied to valence electrons, coupled non-adiabatically to molecular dynamics of the ions, we study the induced dynamics of ethylene subjected to the laser field. We demonstrate the reliable quality of such an approach in comparison to the experimental data on atomic and molecular properties. The impact of ionic motion on the ionization is discussed showing the importance of dealing with electronic and ionic degrees of freedom simultaneously. We explore the various excitation scenarios of ethylene as a function of the laser parameters. We find that the Coulomb fragmentation depends sensitively on the laser frequency. The high laser intensity can cause brute-force Coulomb explosion and the laser pulse length actually has influence on the excitation dynamics of ethylene.

Wang, Z P; Reinhard, P -G; Suraud, E; Zhang, F S

2009-01-01T23:59:59.000Z

413

High energy density micro plasma bunch from multiple laser interaction with thin target  

SciTech Connect (OSTI)

Three-dimensional particle-in-cell simulation is used to investigate radiation-pressure driven acceleration and compression of small solid-density plasma by intense laser pulses. It is found that multiple impacts by presently available short-pulse lasers on a small hemispheric shell target can create a long-living tiny quasineutral monoenergetic plasma bunch of very high energy density.

Xu, Han [National Laboratory for Parallel and Distributed Processing, College of Computer Science, National University of Defense Technology, Changsha 410073 (China); Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, Wei; Luan, S. X.; Xu, Z. Z. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, M. Y., E-mail: myyu@zju.edu.cn [Physics Department, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, Bochum D-44780 (Germany); Cai, H. B.; Zhou, C. T. [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yang, X. H.; Yin, Y.; Zhuo, H. B. [College of Science, National University of Defense Technology, Changsha (China); Wang, J. W. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Murakami, M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan)

2014-01-13T23:59:59.000Z

414

Comparison of EUV spectral and ion emission features from laser-produced Sn and Li plasmas  

E-Print Network [OSTI]

Comparison of EUV spectral and ion emission features from laser- produced Sn and Li plasmas R. W. Coons, D. Campos, M. Crank, S. S. Harilal, and A. Hassanein School of Nuclear Engineering, and Center, and the kinetic energies and fluxes of ions at various laser intensities for both Sn and Li plasmas. The maximum

Harilal, S. S.

415

Nonlinear relativistic interaction of an ultrashort laser pulse with a cold plasma  

E-Print Network [OSTI]

J Fisch. . . . Princeton Plasma Physics Laboratory, Princeton University, Princeton, New JerseyNonlinear relativistic interaction of an ultrashort laser pulse with a cold plasma J M Raxa) and N that results when intense ( 10" W/cm* and above) and ultrashort (one plasma period or shorter) laser pulse

416

BNL | CFN Laser System Qualifications  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser System Qualification There are multiple laser systems at the CFN. Users who will be working with the following class 3B or 4 laser systems are required to complete the Laser...

417

A proposal for testing subcritical vacuum pair production with high power lasers  

E-Print Network [OSTI]

We present a proposal for testing the prediction of non-equilibrium quantum field theory below the Schwinger limit. The proposed experiments should be able to detect a measurable number of gamma rays resulting from the annihilation of pairs in the focal spot of two opposing high intensity laser beams. We discuss the dependence of the expected number of gamma rays with the laser parameters and compare with the estimated background level of gamma hits for realistic laser conditions.

G. Gregori; D. B. Blaschke; P. P. Rajeev; H. Chen; R. J. Clarke; T. Huffman; C. D. Murphy; A. V. Prozorkevich; C. D. Roberts; G. Röpke; S. M. Schmidt; S. A. Smolyansky; S. Wilks; R. Bingham

2010-05-18T23:59:59.000Z

418

Handbook of Pediatric Intensive Care  

Science Journals Connector (OSTI)

...objectionable, but I found that it streamlined the text. This handbook is useful in at least two ways. First, it can serve as a mini-textbook on pediatric intensive care. It is not meant to be a substitute for any of the major works in the field, but it does provide enough information for the reader to gain more... In caring for critically ill children, the demands on one's time are great, and there is often little time left for reading. Although there are a number of excellent, comprehensive books on pediatric critical care that must be read by those in the field, ...

Trager J.D.K.

1996-01-25T23:59:59.000Z

419

BUILDING A CHEMICAL LASER WEAPON  

Science Journals Connector (OSTI)

BUILDING A CHEMICAL LASER WEAPON ... Under fire, Airborne Laser program director confronts challenges of revolutionary weapons system ...

WILLIAM G. SCHULZ

2004-12-20T23:59:59.000Z

420

Laser-Ranging Long Baseline Differential Atom Interferometers for Space  

E-Print Network [OSTI]

High sensitivity differential atom interferometers are promising for precision measurements in science frontiers in space, including gravity field mapping for Earth science studies and gravitational wave detection. We propose a new configuration of twin atom interferometers connected by a laser ranging interferometer (LRI-AI) to provide precise information of the displacements between the two AI reference mirrors and a means to phase-lock the two independent interferometer lasers over long distances, thereby further enhancing the feasibility of long baseline differential atom interferometers. We show that a properly implemented LRI-AI can achieve equivalent functionality to the conventional differential atom interferometer measurement system. LRI-AI isolates the laser requirements for atom interferometers and for optical phase readout between distant locations, thus enabling optimized allocation of available laser power within a limited physical size and resource budget. A unique aspect of LRI-AI also enables...

Chiow, Sheng-wey; Yu, Nan

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Superlinear growth of Rayleigh scattering-induced intensity noise in single-mode fibers  

E-Print Network [OSTI]

Rayleigh scattering generates intensity noise close to an optical carrier that propagates in a single-mode optical fiber. This noise degrades the performance of optoelectronic oscillators and RF-photonic links. When using a broad linewidth laser, we previously found that the intensity noise power scales linearly with optical power and fiber length, which is consistent with guided entropy mode Rayleigh scattering (GEMRS), a third order nonlinear scattering process, in the spontaneous limit. In this work, we show that this behavior changes significantly with the use of a narrow linewidth laser. Using a narrow linewidth laser, we measured the bandwidth of the intensity noise plateau to be 10 kHz. We found that the scattered noise power scales superlinearly with fiber length up to lengths of 10 km in the frequency range of 500 Hz to 10 kHz, while it scales linearly in the frequency range of 10 Hz to 100 Hz. These results suggest that the Rayleigh-scattering-induced intensity noise cannot be explained by third-ord...

Cahill, James P; Zhou, Weimin; Menyuk, Curtis R; Carter, Gary M

2015-01-01T23:59:59.000Z

422

Dense plasma heating and Gbar shock formation by a high intensity flux of energetic electrons  

SciTech Connect (OSTI)

Process of shock ignition in inertial confinement fusion implies creation of a high pressure shock with a laser spike having intensity of the order of a few PW/cm{sup 2}. However, the collisional (Bremsstrahlung) absorption at these intensities is inefficient and a significant part of laser energy is converted in a stream of energetic electrons. The process of shock formation in a dense plasma by an intense electron beam is studied in this paper in a planar geometry. The energy deposition takes place in a fixed mass target layer with the areal density determined by the electron range. A self-similar isothermal rarefaction wave of a fixed mass describes the expanding plasma. Formation of a shock wave in the target under the pressure of expanding plasma is described. The efficiency of electron beam energy conversion into the shock wave energy depends on the fast electron energy and the pulse duration. The model is applied to the laser produced fast electrons. The fast electron energy transport could be the dominant mechanism of ablation pressure creation under the conditions of shock ignition. The shock wave pressure exceeding 1 Gbar during 200–300 ps can be generated with the electron pulse intensity in the range of 5–10 PW/cm{sup 2}. The conclusions of theoretical model are confirmed in numerical simulations with a radiation hydrodynamic code coupled with a fast electron transport module.

Ribeyre, X.; Feugeas, J.-L.; Nicolaď, Ph.; Tikhonchuk, V. T. [University Bordeaux-CNRS-CEA, CELIA, UMR 5107, 33405 Talence (France)] [University Bordeaux-CNRS-CEA, CELIA, UMR 5107, 33405 Talence (France); Gus'kov, S. [University Bordeaux-CNRS-CEA, CELIA, UMR 5107, 33405 Talence (France) [University Bordeaux-CNRS-CEA, CELIA, UMR 5107, 33405 Talence (France); P. N. Lebedev Physical Institute RAS, 53, Leninskii Prospect, Moscow 119991 (Russian Federation)

2013-06-15T23:59:59.000Z

423

Is sustainability science really a science?  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Is sustainability science really a science? Is sustainability science really a science? The team's work shows that although sustainability science has been growing explosively...

424

Computer Science Computer Science?  

E-Print Network [OSTI]

. Data and Information: Meet the challenges of"big data"via information management and through database in electrical engineering and computer science MSAIL: Artificial intelligence group HKN: Eta Kappa Nu honor

Eustice, Ryan

425

HARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE  

E-Print Network [OSTI]

-electron laser (FEL) beamlines which use the har- monic cascade approach to produce coherent XUV & soft X-ray for an integrated system of ultrafast x-ray techniques and lasers, using laser-seeded harmonic cascade FEL's, rfHARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE J. Corlett, W. Fawley

Wurtele, Jonathan

426

Along the Laser Beampath  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

has been installed in the preamplifier modules (PAMs) at the front end of the NIF laser system. The spatial shapers can obscure the laser light at programmed locations within...

427

Laser preheat enhanced ignition  

DOE Patents [OSTI]

A method for enhancing fuel ignition performance by preheating the fuel with laser light at a wavelength that is absorbable by the fuel prior to ignition with a second laser is provided.

Early, James W. (Los Alamos, NM)

1999-01-01T23:59:59.000Z

428

Laser preheat enhanced ignition  

DOE Patents [OSTI]

A method for enhancing fuel ignition performance by preheating the fuel with laser light at a wavelength that is absorbable by the fuel prior to ignition with a second laser is provided. 11 figs.

Early, J.W.

1999-03-02T23:59:59.000Z

429

Laser-assisted electrochemistry  

SciTech Connect (OSTI)

The effect of laser irradiation on electrodeposition processes has been investigated. These studies demonstrated that the addition of laser irradiation to an electroplating process can dramatically enhance plating rates and current efficiencies, as well as improve the morphology of the resultant electrodeposit. During the course of these investigations, the mechanism for the laser enhancement of electrodeposition processes was determined. Experimental evidence was obtained to show that laser irradiation of the substrate results in increased metal ion concentrations at the surface of the electrode due to a laser-induced Soret effect. The laser-induced Soret effect has important implications for laser-assisted electrochemical processing. The increase in the surface concentration of ions allows efficient electrodeposition from dilute solutions. As such, laser- assisted electrodeposition may develop into an environmentally conscious manufacturing process by reducing waste and limiting worker exposure to toxic chemicals.

Glenn, D.F.

1995-05-01T23:59:59.000Z

430

The design of laser trimmable temperature invariant active NMOS filters  

E-Print Network [OSTI]

THE DESIGN OF LASER TRIMMABLE TEMPERATURE INVARIANT ACTIVE NMOS FILTERS A Thesis MATHEW ANTON RYBICKI Submitted to the Graduate College of Teras A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1983 Major Subject: Electrical Engineering THE DESIGN OF LASER TRIMMABLE TEMPERA'IURE INVARIANT ACTIVE NMOS FILTERS A Thesis by MATHEW ANTON RYBICKI Approved as to style and content by: Randall L. Geiger (Chairman of Committee) Phil ip ED...

Rybicki, Mathew Anton

2012-06-07T23:59:59.000Z

431

CMOS ROM arrays programmable by laser beam scanning  

E-Print Network [OSTI]

CMOS ROM ARRAYS PROGRAMMABLE BY LASER BEAM SCANNING A Thesis bY JONG JUNE LEE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1984 Major Subject... : Electrical Engineering CMOS ROM ARRAYS PROGRAMMABLE BY LASER BEAM SCANNING A Thesis by JONGJUNE LEE Approved as to style and content by: Noel R. Strader II (Chairman of Committee) Philli E. Allen (Member) Philip S. Noe (Member) Daniel Colunga...

Lee, Jongjune

2012-06-07T23:59:59.000Z

432

The effects of high intensity continuous auditory stimulation on the perception of visual display information  

E-Print Network [OSTI]

THE EFFECTS OF HIGH INTENSITY CONTINUOUS AUDITORY STIMULATION ON THE PERCEPTION OF VISUAL DISPLAY INFORMATION A Thesis by WILLIAM HAROLD PERSKY Submitted to the Graduate College of Texas AS M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE May 1972 Major Subject: Industrial Hygiene THE EFFECTS OF HIGH INTENSITY CONTINUOUS AUDITORY STIMULATION ON THE PERCEPTION OF VISUAL DISPLAY INFORMATION A Thesis by WILLIAM HAROLD PERSKY Approved...

Persky, William Harold

1972-01-01T23:59:59.000Z

433

Short wavelength laser  

DOE Patents [OSTI]

A short wavelength laser (28) is provided that is driven by conventional-laser pulses (30, 31). A multiplicity of panels (32), mounted on substrates (34), are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path (42). When the panels (32) are illuminated by the conventional-laser pulses (30, 31), single pass EUV or soft x-ray laser pulses (44, 46) are produced.

Hagelstein, Peter L. (Livermore, CA)

1986-01-01T23:59:59.000Z

434

Laser Heat Treatment [Laser Applications Laboratory] - Nuclear Engineering  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Heat Treatment Heat Treatment Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Heat Treatment Project description: Optimization of laser beam heat treatment. Category: Project with industrial partner (Caterpillar and USCAR) Bookmark and Share Heat treatment optics

435

Computer Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Computer Science Computer Science1354608000000Computer ScienceSome of these resources are LANL-only and will require Remote Access.NoQuestions? 667-5809library@lanl.gov Computer...

436

Information Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Information Science Information Science1354608000000Information ScienceSome of these resources are LANL-only and will require Remote Access.NoQuestions? 667-5809library@lanl.gov...

437

Laser bottom hole assembly  

DOE Patents [OSTI]

There is provided for laser bottom hole assembly for providing a high power laser beam having greater than 5 kW of power for a laser mechanical drilling process to advance a borehole. This assembly utilizes a reverse Moineau motor type power section and provides a self-regulating system that addresses fluid flows relating to motive force, cooling and removal of cuttings.

Underwood, Lance D; Norton, Ryan J; McKay, Ryan P; Mesnard, David R; Fraze, Jason D; Zediker, Mark S; Faircloth, Brian O

2014-01-14T23:59:59.000Z

438

Earth Sciences Environmental Earth Sciences,  

E-Print Network [OSTI]

94 Earth Sciences­ Environmental Earth Sciences, Geology Degree options MGeol (Single Honours Degrees) Earth Sciences BSc (Single Honours Degrees) Environmental Earth Sciences Geology BSc (Joint placement. * The Geology and Environmental Earth Sciences degrees are accredited by the Geological Society

Brierley, Andrew

439

1 Political Science POLITICAL SCIENCE  

E-Print Network [OSTI]

1 Political Science POLITICAL SCIENCE With Capitol Hill nearby and the White House just blocks away, GW is the ideal place to study political science. Students in the program benefit from rigorous study and behavioral sciences discipline in the Columbian College of Arts and Sciences, the program examines politics

Vertes, Akos

440

1 Forensic Sciences FORENSIC SCIENCES  

E-Print Network [OSTI]

1 Forensic Sciences FORENSIC SCIENCES As part of the Columbian College of Arts and Sciences' natural, mathematical and biomedical sciences programs, the forensic sciences program provides an understanding of the integration of forensic disciplines with the investigation of criminal activity, along

Vertes, Akos

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

FORENSIC SCIENCE About Forensic Science  

E-Print Network [OSTI]

Fact Sheet FORENSIC SCIENCE About Forensic Science: The Forensic Science program at SJSU offers: The SJSU Forensic Science program delivers coursework and training to · Empowergraduatestobecomeagentsofchangetorecognize, document and report errors and injustices in the practice of forensic science and crime scene

Su, Xiao

442

National Ignition Facility & Photon Science NIF AT A GLANCe  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

& Photon Science NIF AT A GLANCe the national ignition Facility at a glance The National Ignition Facility (NIF) is the world's largest laser system, housed in a 10-story building...

443

Photo of the Week: Laser Beats Rock | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Laser Beats Rock Laser Beats Rock Photo of the Week: Laser Beats Rock April 8, 2013 - 5:28pm Addthis On August 5, 2012, the Curiosity rover touched down on the surface of Mars. The ChemCam instrument package, developed at Los Alamos National Laboratory, is a device mounted on the Mars Curiosity rover that uses two remote sensing instruments: the Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). The LIBS fires a powerful laser that determines chemical compositions of rock and soil samples, while the RMI takes photos of the samples within the rover's vicinity. In this photo, the ChemCam is being prepared in the clean room prior to the launch of NASA's Mars Science Laboratory mission. Learn more about the ChemCam. | Photo courtesy of Los Alamos National Laboratory.

444

Lasers, Electron Beams and New Years Resolutions | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Lasers, Electron Beams and New Years Resolutions Lasers, Electron Beams and New Years Resolutions Lasers, Electron Beams and New Years Resolutions March 2, 2011 - 3:43pm Addthis Charles Rousseaux Charles Rousseaux Senior Writer, Office of Science What are the key facts? The electron beam that powers Jefferson Lab's Free-Electron Laser pumped out a record power input of 500 kilvolts using an innovative energy-recovery system that amplifies energy with far less power. A sufficiently powerful laser could make an effective defensive weapon, as well as accurate detection and tracking. The few folks still keeping their New Year's resolutions to work out might be the first to appreciate the recent record-breaking lift by the Energy Department's Jefferson Lab. Take a steel dumbbell. Hoist it up - lift with your legs! - onto a stand. Then add another ...and another

445

Iron and Steel Energy Intensities  

U.S. Energy Information Administration (EIA) Indexed Site

If you are having trouble, call 202-586-8800 for help. Home > >Energy Users > Energy Efficiency Page > Iron and Steel Energy Intensities First Use of Energy Blue Bullet First Use/Value of Production Blue Bullet First Use/Ton of steel End Uses of Consumption Blue Bullet Total End Use/Value of Production Blue Bullet Total End Use/Ton of Steel Boiler Fuel as End Use Blue Bullet Boiler Fuel /Value of Production Blue Bullet Boiler Fuel /Ton of Steel Process Heating as End Use Blue Bullet Process Heating Fuel /Ton of Steel Blue Bullet Process Heating /Value of Production Machine Drive as End Use Blue Bullet Machine Drive Fuel/Ton of Steel Blue Bullet Machine Drive Fuel /Value of Production Expenditures Blue Bullet Purchased Fuel /Ton of Steel Blue Bullet Purchased Fuel /Value of Production

446

Energy Intensity Baselining and Tracking Guidance  

Broader source: Energy.gov [DOE]

The Energy Intensity Baselining and Tracking Guidance for the Better Buildings, Better Plants Program helps companies meet the program’s reporting requirements by describing the steps necessary to develop an energy consumption and energy intensity baseline and calculating consumption and intensity changes over time.

447

Science Organizations  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Organizations Science Organizations National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place...

448

Fermilab | Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

feature photo feature photo feature photo feature photo feature photo Science Navbar Toggle About Quick Info Science History Organization Photo and Video Gallery Diversity...

449

J. Quanr. .Specrrosc. Radiar. Trmfir Vol. 54, No. l/2, pp. 40141 I. 1995 Copyright 0 1995 Elsevier Science Ltd  

E-Print Network [OSTI]

.50+ 0.00 PICOSECOND x-RAYS FROM SUBPICOSECOND- LASER-PRODUCED HOT-DENSE MATTER D. UMSTADTER, J. WORKMAN-intensity laser-plasma interactions are investigated experimentally with temporally and spectrally resolved soft x-ray for a laser pulse width T,- 400 fs. With low contrast (lo'), the x-ray spectrum in the 1 = 40-100 A spectral

Umstadter, Donald

450

HELIOS: A high intensity chopper spectrometer at LANSCE  

SciTech Connect (OSTI)

A proposal to construct a high intensity chopper spectrometer at LANSCE as part of the SPSS upgrade project is discussed. HELIOS will be optimized for science requiring high sensitivity neutron spectroscopy. This includes studies of phonon density of states in small polycrystalline samples, magnetic excitations in quantum magnets and highly correlated electron systems, as well as parametric studies (as a function of pressure, temperature, or magnetic field) of S(Q,{omega}). By employing a compact design together with the use of supermirror guide in the incident flight path the neutron flux at HELIOS will be significantly higher than any other comparable instrument now operating.

Mason, T.E. [Oak Ridge National Lab., TN (United States); Broholm, C. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy; Fultz, B. [California Inst. of Tech., Pasadena, CA (United States). Dept. of Materials Science] [and others

1998-12-31T23:59:59.000Z

451

Creation of electron-positron plasma with superstrong laser field  

E-Print Network [OSTI]

We present a short review of recent progress in studying QED effects of interaction of ultra-relativistic laser pulses with vacuum and $e^-e^+$ plasma. The development of laser technologies promises very rapid growth of laser intensities in close future already. Two exawatt class facilities (ELI and XCELS, Russia) in Europe are already in the planning stage. Realization of these projects will make available a laser of intensity $\\sim 10^{26}$W/cm$^2$ or even higher. Therefore, discussion of nonlinear optical effects in vacuum are becoming urgent for experimentalists and are currently gaining much attention. We show that, in spite of the fact that the respective field strength is still essentially less than $E_S=m^2c^3/e\\hbar=1.32\\cdot 10^{16}$V/cm, the nonlinear vacuum effects will be accessible for observation at ELI and XCELS facilities. The most promissory for observation is the effect of pair creation by laser pulse in vacuum. It is shown, that at intensities $\\sim 5\\cdot 10^{25}$W/cm$^2$, creation even o...

Narozhny, N B

2013-01-01T23:59:59.000Z

452

Colloquium: Aligning molecules with strong laser pulses Henrik Stapelfeldt  

E-Print Network [OSTI]

-known example of the dependence of reactivity upon the relative orientation of the reactants is the SN2 reaction and nanoscale processing to stereodynamics and control of chemical reactions. After placing the intense laser transitions 554 V. Conclusion 555 Acknowledgments 556 References 556 I. INTRODUCTION Most chemical reactions

Seideman, Tamar

453

Diagnostics for Fast Ignition Science  

SciTech Connect (OSTI)

The concept for Electron Fast Ignition Inertial Confinement Fusion demands sufficient laser energy be transferred from the ignitor pulse to the assembled fuel core via {approx}MeV electrons. We have assembled a suite of diagnostics to characterize such transfer. Recent experiments have simultaneously fielded absolutely calibrated extreme ultraviolet multilayer imagers at 68 and 256eV; spherically bent crystal imagers at 4 and 8keV; multi-keV crystal spectrometers; MeV x-ray bremmstrahlung and electron and proton spectrometers (along the same line of sight); nuclear activation samples and a picosecond optical probe based interferometer. These diagnostics allow careful measurement of energy transport and deposition during and following laser-plasma interactions at extremely high intensities in both planar and conical targets. Augmented with accurate on-shot laser focal spot and pre-pulse characterization, these measurements are yielding new insight into energy coupling and are providing critical data for validating numerical PIC and hybrid PIC simulation codes in an area that is crucial for many applications, particularly fast ignition. Novel aspects of these diagnostics and how they are combined to extract quantitative data on ultra high intensity laser plasma interactions are discussed, together with implications for full-scale fast ignition experiments.

MacPhee, A; Akli, K; Beg, F; Chen, C; Chen, H; Clarke, R; Hey, D; Freeman, R; Kemp, A; Key, M; King, J; LePape, S; Link, A; Ma, T; Nakamura, N; Offermann, D; Ovchinnikov, V; Patel, P; Phillips, T; Stephens, R; Town, R; Wei, M; VanWoerkom, L; Mackinnon, A

2008-05-06T23:59:59.000Z

454

Superconducting laser photocathode RF gun at BNL | U.S. DOE Office of  

Office of Science (SC) Website

Superconducting laser photocathode RF Superconducting laser photocathode RF gun at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Superconducting laser photocathode RF gun at BNL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Superconducting laser photocathode RF gun Developed at: Brookhaven National Laboratory (BNL), New York and Advanced Energy Systems,

455

Method and apparatus for laser-controlled proton beam radiology  

DOE Patents [OSTI]

A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H.sup.- beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H.sup.- beam and laser beam to produce a neutral beam therefrom within a subsection of the H.sup.- beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H.sup.- beam in order to form the neutral beam in subsections of the H.sup.- beam. As the scanning laser moves across the H.sup.- beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser.

Johnstone, Carol J. (Warrenville, IL)

1998-01-01T23:59:59.000Z

456

Method and apparatus for laser-controlled proton beam radiology  

DOE Patents [OSTI]

A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H{sup {minus}} beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H{sup {minus}} beam and laser beam to produce a neutral beam therefrom within a subsection of the H{sup {minus}} beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H{sup {minus}} beam in order to form the neutral beam in subsections of the H{sup {minus}} beam. As the scanning laser moves across the H{sup {minus}} beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser. 9 figs.

Johnstone, C.J.

1998-06-02T23:59:59.000Z

457

Ultrafast Laser Facility | Photosynthetic Antenna Research Center  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Ultrafast Laser Facility Ultrafast Laser Facility Click for an Overview of the Ultrafast Laser Facility The PARC Ultrafast Laser Facility, under the direction of Associate Director...

458

Science | ORNL Neutron Sciences  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Neutron Science Neutron Science Neutron Scattering Science Neutrons are one of the fundamental particles that make up matter and have properties that make them ideal for certain types of research. In the universe, neutrons are abundant, making up more than half of all visible matter. Neutron scattering provides information about the positions, motions, and magnetic properties of solids. When a beam of neutrons is aimed at a sample, many neutrons will pass through the material. But some will interact directly with atomic nuclei and "bounce" away at an angle, like colliding balls in a game of pool. This behavior is called neutron diffraction, or neutron scattering. Using detectors, scientists can count scattered neutrons, measure their energies and the angles at which they scatter, and map their final position

459

BNL | ATF Laser Safety  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ATF Laser Safety ATF Laser Safety To be present in a secured laser area at ATF, a person must either have the required laser training, or be continuously escorted by someone who has such training: The training consists of an eye exam, BNL general laser safety lecture, and formal ATF laser familiarization. Untrained personnel should not be instructed to enter interlocked areas or be escorted into an area and left unattended. If someone without training must enter a secured area, they must be continuously escorted, and are considered spectators, which means they may not perform any work in the area. At ATF, there are 3 classes of personnel authorized to enter secured areas: Experimental operators may secure areas, perform approved experiments with beams from facility lasers (YAG + CO2) or FEL beams, and

460

Statistical properties of backscattered semiconductor laser radiation with different degrees of coherence  

SciTech Connect (OSTI)

This paper compares the statistical properties of the backscatter intensity in a single-mode optical fibre for semiconductor lasers with a high and a low degree of coherence. We demonstrate that, when short probe pulses are used, shorter than the coherence times of the lasers, the statistical properties of the backscatter intensity obtained with the two lasers are identical, and the intensity distribution over an ensemble of independent fibre sections has an exponential form for both. With increasing probe pulse duration, the backscatter intensity distribution obtained with the shorter coherence time laser approaches a Gaussian one, whereas the distribution function obtained with the high-coherence laser remains nearly exponential. Reflectograms of a coherent reflectometer that relies on the detection of backscattered radiation have the highest contrast for an exponential backscatter intensity distribution over an ensemble of independent fibre sections. The reflectometer then probably has the highest sensitivity to external influences. This leads us to conclude that, when short probe pulses are used, which ensure high spatial resolution (10 m and better), one can use a laser with a short coherence time, equal to the pulse duration.

Alekseev, A E; Tezadov, Ya A; Potapov, V T

2012-01-31T23:59:59.000Z

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Fusion reactions initiated by laser-accelerated particle beams in a laser-produced plasma  

E-Print Network [OSTI]

The advent of high-intensity pulsed laser technology enables the generation of extreme states of matter under conditions that are far from thermal equilibrium. This in turn could enable different approaches to generating energy from nuclear fusion. Relaxing the equilibrium requirement could widen the range of isotopes used in fusion fuels permitting cleaner and less hazardous reactions that do not produce high energy neutrons. Here we propose and implement a means to drive fusion reactions between protons and boron-11 nuclei, by colliding a laser-accelerated proton beam with a laser-generated boron plasma. We report proton-boron reaction rates that are orders of magnitude higher than those reported previously. Beyond fusion, our approach demonstrates a new means for exploring low-energy nuclear reactions such as those that occur in astrophysical plasmas and related environments.

Labaune, C; Depierreux, S; Goyon, C; Loisel, G; Yahia, V; Rafelski, J

2013-01-01T23:59:59.000Z

462

Improved ion acceleration via laser surface plasma waves excitation  

SciTech Connect (OSTI)

The possibility of enhancing the emission of the ions accelerated in the interaction of a high intensity ultra-short (<100 fs) laser pulse with a thin target (<10?{sub 0}), via surface plasma wave excitation is investigated. Two-dimensional particle-in-cell simulations are performed for laser intensities ranging from 10{sup 19} to 10{sup 20} Wcm{sup ?2}?m{sup 2}. The surface wave is resonantly excited by the laser via the coupling with a modulation at the target surface. In the cases where the surface wave is excited, we find an enhancement of the maximum ion energy of a factor ?2 compared to the cases where the target surface is flat.

Bigongiari, A. [CEA/DSM/LSI, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France) [CEA/DSM/LSI, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); TIPS/LULI, Université Paris 6, CNRS, CEA, Ecole Polytechnique, 3, rue Galilée, 94200 Ivry-sur-Seine (France); Raynaud, M. [CEA/DSM/LSI, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)] [CEA/DSM/LSI, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Riconda, C. [TIPS/LULI, Université Paris 6, CNRS, CEA, Ecole Polytechnique, 3, rue Galilée, 94200 Ivry-sur-Seine (France)] [TIPS/LULI, Université Paris 6, CNRS, CEA, Ecole Polytechnique, 3, rue Galilée, 94200 Ivry-sur-Seine (France); Héron, A. [CPHT, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)] [CPHT, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)

2013-05-15T23:59:59.000Z

463

Laser beam apparatus and method for analyzing solar cells  

DOE Patents [OSTI]

A laser beam apparatus and method for analyzing, inter alia, the current versus voltage curve at the point of illumination on a solar cell and the open circuit voltage of a solar cell. The apparatus incorporates a lock-in amplifier, and a laser beam light chopper which permits the measurement of the AC current of the solar cell at an applied DC voltage at the position on the solar cell where the cell is illuminated and a feedback scheme which permits the direct scanning measurements of the open circuit voltage. The accuracy of the measurement is a function of the intensity and wavelength of the laser light with respect to the intensity and wavelength distribution of sunlight and the percentage the dark current is at the open circuit voltage to the short circuit current of the solar cell.

Staebler, David L. (Lawrenceville, NJ)

1980-01-01T23:59:59.000Z

464

Calibration of a gated flat field spectrometer as a function of x-ray intensity  

SciTech Connect (OSTI)

We present an experimental determination of the response of a gated flat-field spectrometer at the Shenguang-II laser facility. X-rays were emitted from a target that was heated by laser beams and then were divided into different intensities with a step aluminum filter and collected by a spectrometer. The transmission of the filter was calibrated using the Beijing Synchrotron Radiation Facility. The response characteristics of the spectrometer were determined by comparing the counts recorded by the spectrometer with the relative intensities of the x-rays transmitted through the step aluminum filter. The response characteristics were used to correct the transmission from two shots of an opacity experiment using the same samples. The transmissions from the two shots are consistent with corrections, but discrepant without corrections.

Xiong, Gang; Yang, Guohong; Li, Hang; Zhang, Jiyan, E-mail: zhangjiyanzjy@sina.com; Zhao, Yang; Hu, Zhimin; Wei, Minxi; Qing, Bo; Yang, Jiamin; Liu, Shenye; Jiang, Shaoen [Research Center of Laser Fusion, China Academy of Engineering Physics, P. O. Box 919-986, Mianyang 621900 (China)] [Research Center of Laser Fusion, China Academy of Engineering Physics, P. O. Box 919-986, Mianyang 621900 (China)

2014-04-15T23:59:59.000Z

465

Science Facilities  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Electron Microscopy Lab Ion Beam Materials Lab Matter-Radiation Interactions in Extremes (MaRIE) Proton Radiography Trident Laser Facility LOOK INTO LANL - highlights...

466

Output-power fluctuations of flowing-gas CO/sub 2/ lasers with unstable resonators  

SciTech Connect (OSTI)

An experimental study was made of the influence of different factors on the stability of the output intensity of a flowing-gas CO/sub 2/ laser with an unstable resonator. The measured amplitude--frequency characteristics of the intensity fluctuation spectrum had resonance peaks at multiples of the frequency corresponding to the transit time of the gas to the optic axis of the resonator. A rise in the efficiency of the laser system was found to be accompanied by an increase in the amplitude of the fluctuations of the radiation intensity.

Artamonov, A.V.; Konev, V.A.; Likhanskii, V.V.; Napartovich, A.P.

1984-06-01T23:59:59.000Z

467

Phase I Trial of an Infrared Pulsed Laser Device in Patients with Advanced Neoplasias  

Science Journals Connector (OSTI)

...sectioned during the operation and viable tumor...interactions with biological systems. FASEB J., 7...Lubart R. 780 nm low power diode laser irradiation...1981. 21 . WHO handbook for reporting results...neuroscience: low-power laser effect on peripheral...and central nervous system (basic science...

Luis A. Santana-Blank; Elizabeth Rodríguez-Santana; Fernando Vargas; Heberto Reyes; Pablo Fernández-Andrade; Saide Rukos; and Karin E. Santana-Rodríguez

2002-10-01T23:59:59.000Z

468

Laser system using ultra-short laser pulses  

DOE Patents [OSTI]

A laser system using ultrashort laser pulses is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal.

Dantus, Marcos (Okemos, MI); Lozovoy, Vadim V. (Okemos, MI); Comstock, Matthew (Milford, MI)

2009-10-27T23:59:59.000Z

469

Building Science  

Broader source: Energy.gov (indexed) [DOE]

Science Science The "Enclosure" Joseph Lstiburek, Ph.D., P.Eng, ASHRAE Fellow www.buildingscience.com * Control heat flow * Control airflow * Control water vapor flow * Control rain * Control ground water * Control light and solar radiation * Control noise and vibrations * Control contaminants, environmental hazards and odors * Control insects, rodents and vermin * Control fire * Provide strength and rigidity * Be durable * Be aesthetically pleasing * Be economical Building Science Corporation Joseph Lstiburek 2 Water Control Layer Air Control Layer Vapor Control Layer Thermal Control Layer Building Science Corporation Joseph Lstiburek 3 Building Science Corporation Joseph Lstiburek 4 Building Science Corporation Joseph Lstiburek 5 Building Science Corporation

470

Laser-driven hole boring and gamma-ray emission in high-density plasmas  

E-Print Network [OSTI]

Ion acceleration in laser-produced dense plasmas is a key topic of many recent investigations thanks to its potential applications. Besides, at forthcoming laser intensities ($I \\gtrsim 10^{23} \\text{W}\\,\\text{cm}^{-2}$) interaction of laser pulses with plasmas can be accompanied by copious gamma-ray emission. Here we demonstrate the mutual influence of gamma-ray emission and ion acceleration during relativistic hole boring in high-density plasmas with ultra-intense laser pulses. If gamma-ray emission is abundant, laser pulse reflection and hole-boring velocity are lower and gamma-ray radiation pattern is narrower than in the case of low emission. Conservation of energy and momentum allows one to elucidate the effects of gamma-ray emission which are more pronounced at higher hole-boring velocities.

Nerush, Evgeny

2014-01-01T23:59:59.000Z

471

Ablation driven by hot electrons generated during the ignitor laser pulse in shock ignition  

SciTech Connect (OSTI)

An analytical model for the ablation driven by hot electrons is presented. The hot electrons are assumed to be generated during the high intensity laser spike used to produce the ignitor shock wave in the shock ignition driven inertial fusion concept, and to carry on the absorbed laser energy in its totality. Efficient energy coupling requires to keep the critical surface sufficiently close to the ablation front and this goal can be achieved for high laser intensities provided that the laser wavelength is short enough. Scaling laws for the ablation pressure and the other relevant magnitudes of the ablation cloud are found in terms of the laser and target parameters. The effect of the preformed plasma assembled by the compression pulse, previous to the ignitor, is also discussed. It is found that a minimum ratio between the compression and the ignitor pulses would be necessary for the adequate matching of the corresponding scale lengths.

Piriz, A. R.; Rodriguez Prieto, G. [E.T.S.I. Industriales, Universidad de Castilla-La Mancha and Instituto de Investigaciones Energeticas, 13071 Ciudad Real (Spain); Tahir, N. A. [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt (Germany); Zhang, Y. [School of Physics and Optoelectronic Technology, Dalian University of Technology, 116024 Dalian (China); Liu, S. D.; Zhao, Y. T. [Institute of Modern Physics, Chinese Academy of Science, 730000 Lanzhou (China)

2012-12-15T23:59:59.000Z

472

Long-period fiber grating inscription under high-intensity 352 nm femtosecond irradiation: Three-photon absorption  

E-Print Network [OSTI]

-photon absorption and energy deposition in cladding Stephen A. Slattery, David N. Nikogosyan * Department of Physics-intensity 211 and 264 nm laser pulses. Three-photon absorption coefficients for pure fused silica in the fiber cladding and the core. It was shown that the deposition of the majority of the absorbed energy

Nikogosyan, David N.

473

Intense femtosecond photoexcitation of bulk and monolayer MoS2  

E-Print Network [OSTI]

The effect of femtosecond laser irradiation on bulk and single-layer MoS2 on silicon oxide is studied. Optical, Field Emission Scanning Electron Microscopy (FESEM) and Raman microscopies were used to quantify the damage. The intensity of A1g and E2g1 vibrational modes was recorded as a function of the number of irradiation pulses. The observed behavior was attributed to laser-induced bond breaking and subsequent atoms removal due to electronic excitations. The single-pulse optical damage threshold was determined for the monolayer and bulk under 800nm and 1030nm pulsed laser irradiation and the role of two-photon versus one photon absorption effects is discussed.

Paradisanos, I; Fotakis, C; Kioseoglou, G; Stratakis, E

2015-01-01T23:59:59.000Z

474

Proton Accelerator Physics Continued| U.S. DOE Office of Science...  

Office of Science (SC) Website

Energy Frontier More Information High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier Cosmic Frontier...

475

Political Science College of Arts and Sciences  

E-Print Network [OSTI]

Political Science College of Arts and Sciences Degree Options Bachelor of Arts in Political Science General Political Science Global Politics Political Science Pre-Law Minors Political Science Program Law Campaign worker Politics Marketing and sales Nonprofit administration Consultant Certification

Collins, Gary S.

476

[Faculty of Science Information and Computing Sciences  

E-Print Network [OSTI]

[Faculty of Science Information and Computing Sciences] Terminating combinator parsers in Agda and Computing Sciences Utrecht University June 12, 2008 #12;[Faculty of Science Information and Computing Sciences] 2 Overview Totality Parser combinators Terminating combinator parsers #12;[Faculty of Science

Löh, Andres

477

LASER SAFETY POLICY Policy Statement  

E-Print Network [OSTI]

LASER SAFETY POLICY Policy Statement Each department that acquires or operates lasers for use in laboratories or research is responsible for reporting laser acquisition to the Office of Laboratory Safety, selecting a departmental deputy laser safety officer, mandating training for its laser operators

Vertes, Akos

478

OMEGA Extended Performance Laser System  

E-Print Network [OSTI]

at UR-LLE is close to that required for ignition to occur. #12;The OMEGA Extended Performance (EP) laserOMEGA Extended Performance Laser System R. L. McCrory University of Rochester Laboratory for Laser­18 February 2008 #12;OMEGA Extended Performance Laser System R.L. McCrory Laboratory for Laser Energetics

479

Energetic proton generation from intense Coulomb explosion of large-size ethane clusters  

Science Journals Connector (OSTI)

An experimental investigation is performed on the interaction of intense femtosecond laser pulses at the intensity of 6?×?1017?W/cm2 (55 fs 160?mJ at 800?nm) with ethane cluster (C2H6) N jets prepared under the backing pressure of 30 bars at room temperature (298?K). The experiment results indicate the generation of energetic protons whose average and maximum kinetic energies are 12.2 and 138.1?keV respectively by Coulomb explosion of (C2H6) N clusters. (C2H6) N clusters of 5?nm in radius are generated in the experiment which are 1.7 times larger than that of (CH4) N clusters prepared in the same conditions. Empirical estimation suggests that (C2H6) N clusters with radius of about 9.6?nm can be prepared at 80-bars backing pressure at 308?K. While (C2H6) N clusters of so large size are irradiated by sufficiently intense laser pulses the average energy of protons will be increased up to 50?keV. It is inferred that such large-size deuterated ethane clusters (C2D6) N will favor more efficient neutron generation due to the significant increase of the D-D nuclear reaction cross section in laser-driven cluster nuclear fusion.

Song Li; Zili Zhou; Ye Tian; Haiyang Lu; Wentao Wang; Jingjing Ju; Hongyu Li; Yi Xu; Yuxin Leng; Guoquan Ni; Cheng Wang; Jiansheng Liu

2013-01-01T23:59:59.000Z

480

Faculty of Science Computer Science  

E-Print Network [OSTI]

Faculty of Science Computer Science Software engineering, network and system analysis continue a variety of computer science programs to prepare students for a career in the technology industry or in research and academia. A computer science degree provides an in-depth understanding of the fundamentals

Note: This page contains sample records for the topic "intensity laser science" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Laser Safety Inspection Criteria  

SciTech Connect (OSTI)

A responsibility of the Laser Safety Officer (LSO) is to perform laser safety audits. The American National Standard Z136.1 Safe use of Lasers references this requirement in several sections: (1) Section 1.3.2 LSO Specific Responsibilities states under Hazard Evaluation, ''The LSO shall be responsible for hazards evaluation of laser work areas''; (2) Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''; and (3) Appendix D, under Survey and Inspections, it states, ''the LSO will survey by inspection, as considered necessary, all areas where laser equipment is used''. Therefore, for facilities using Class 3B and or Class 4 lasers, audits for laser safety compliance are expected to be conducted. The composition, frequency and rigueur of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms. In many institutions, a sole Laser Safety Officer (LSO) or a number of Deputy LSO's perform these audits. For that matter, there are institutions that request users to perform a self-assessment audit. Many items on the common audit list and the associated findings are subjective because they are based on the experience and interest of the LSO or auditor in particular items on the checklist. Beam block usage is an example; to one set of eyes a particular arrangement might be completely adequate, while to another the installation may be inadequate. In order to provide more consistency, the National Ignition Facility Directorate at Lawrence Livermore National Laboratory (NIF-LLNL) has established criteria for a number of items found on the typical laser safety audit form. These criteria are distributed to laser users, and they serve two broad purposes: first, it gives the user an expectation of what will be reviewed by an auditor, and second, it is an opportunity to explain audit items to the laser user and thus the reasons for some of these items. Some examples are given from the audit criteria handout. As an explanatory key to the reader, an Operational Safety Procedure (OSP) as a formally reviewed safety procedure required for all Class 3B and Class 4 laser installations. An ''OSP Binder'' contains all safety documentation related to a given laser operation and serves as a central repository for documents, such as the OSP, interlock logs, lessons learned, contact information etc. ''Unattended Operation'' refers to approved procedures for unattended operation of the laser installation and may include operation beyond normal working hours. ''L-train'' is the LLNL training tracking system.

Barat, K

2005-02-11T23:59:59.000Z

482

Security Science & Technology | Nuclear Science | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Research Areas Fuel Cycle Science & Technology Fusion Nuclear Science Isotope Development and Production Nuclear Security Science & Technology Border Security Comprehensive...

483

Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes  

E-Print Network [OSTI]

Design considerations for a laser-plasma linear collider,"E.Esarey, and W.P.Leemans, "Free-electron laser driven bythe LBNL laser-plasma accelerator," in Proc. Adv. Acc. Con.

Geddes, C.G.R.

2011-01-01T23:59:59.000Z

484

DOI: 10.1126/science.1216852 , 681 (2012);337Science  

E-Print Network [OSTI]

challenges, depletes energy reserves, and undermines human water security and ecosystem health. Here we, but it is often energy-intensive and comes at a steep ec- ological price. In the developing world, on the otherScience2012 by the American Association for the Advancement of Science; all rights reserved. The title

Marusic, Ivan

485

Science Projects  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Argonne Argonne Science Project Ideas! Our Science Project section provides you with sample classroom projects and experiments, online aids for learning about science, as well as ideas for Science Fair Projects. Please select any project below to continue. Also, if you have an idea for a great project or experiment that we could share, please click our Ideas page. We would love to hear from you! Science Fair Ideas Science Fair Ideas! The best ideas for science projects are learning about and investigating something in science that interests you. NEWTON has a list of Science Fair linkd that can help you find the right topic. Toothpick Bridge Web Sites Toothpick Bridge Sites! Building a toothpick bridge is a great class project for physics and engineering students. Here are some sites that we recommend to get you started!

486

Science DMZ for ALS  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ALS Science Engagement Move your data Programs & Workshops Science Requirements Reviews Case Studies OSCARS Case Studies Science DMZ Case Studies Science DMZ @ UF Science DMZ @ CU...

487

Science DMZ Case Studies  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Studies Science Engagement Move your data Programs & Workshops Science Requirements Reviews Case Studies OSCARS Case Studies Science DMZ Case Studies Science DMZ @ UF Science DMZ @...

488

NERSC Science Gateways  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

QCD, Materials Science, Science Gateways About Science Gateways A science gateway is a web based interface to access HPC computers and storage systems. Gateways allow science...

489

Polarization feedback laser stabilization  

DOE Patents [OSTI]

A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other. 4 figs.

Esherick, P.; Owyoung, A.

1987-09-28T23:59:59.000Z

490

Energy Intensity Baselining and Tracking Guidance  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Learn more at betterbuildings.energy.gov Energy Intensity Baselining and Tracking Guidance i Preface The U.S. Department of Energy's (DOE) Better Buildings, Better Plants Program...

491

Computational modeling of laser-plasma interactions: Pulse self-modulation and energy transfer between intersecting laser pulses  

Science Journals Connector (OSTI)

The nonlinear interaction of intense femtosecond laser pulses with a self-induced plasma channel in air and the energy transfer between two intersecting laser pulses were simulated using the finite-difference time-domain particle-in-cell method. Implementation of a simple numerical code enabled modeling of various phenomena, including pulse self-modulation in the spatiotemporal and spectral domains, conical emission, and energy transfer between two intersecting laser beams. The mechanism for energy transfer was found to be related to a plasma waveguide array induced by Moiré patterns of the interfering electric fields. The simulation results provide a persuasive replication and explanation of previous experimental results, when carried out under comparable physical conditions, and lead to prediction of others. This approach allows us to further examine the effect of the laser and plasma parameters on the simulation results and to investigate the underlying physics.

Rotem Kupfer; Boris Barmashenko; Ilana Bar

2013-07-17T23:59:59.000Z

492

Terahertz Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We provide an overview of terahertz quantum cascade lasers based on resonant-phonon depopulation and metal-metal waveguides, including two-phonon resonant-phonon depopulation...

Williams, Benjamin; Kumar, Sushil; Qin, Qi; Lee, Alan Wei Min; Hu, Qing; Reno, John L; Wasilewski, Z R; Liu, H C

493

Laser Electron Gamma Source. Biennial progress report  

SciTech Connect (OSTI)

The LEGS facility provides intense, polarized, monochromatic {gamma}-ray beams by Compton backscattering laser light from relativistic electrons circulating in the X-Ray storage ring of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. With the start of ring operations at 2.8 GeV, LEGS {gamma}-ray energies now extend to 370 MeV. Considerable progress has been made in the development of a new laser system that will increase the beam energies to 470 MeV, and this system is expected to come into operation before the next biennial report. The total flux is administratively held at 6 {times} 10{sup 6} s{sup {minus}1}. The {gamma}-ray energy is determined, with a resolution of 5.5 MeV, by detecting the scattering electrons in a magnetic spectrometer. This spectrometer can `tag` all {gamma}-rays with energies from 185 MeV up to the Compton edge. The beam spot size at the target position is 8 mm (V) {times} 18 mm (H), FWHM. For a single laser wavelength, the linear polarization of the beam is 98% at the Compton edge and decreases to 50% at about 1/2 the energy of the edge. By choosing the laser wavelengths appropriately the polarization can be maintained above 85% throughout the tagging range. During the last two years, experimental running at LEGS occupied an average of 3000 hours annually. Highlights of some of the programs are discussed below.

Sandorfi, A.M. [ed.; Caracappa, A.; Kuczewski, A.; Kistner, O.C.; Lincoln, F.; Miceli, L.; Thorn, C.E. [Brookhaven National Lab., Upton, NY (United States); Hoblit, S. [Univ. of Virginia, Charlottesville, VA (United States). Dept. of Physics; Khandaker, M. [Brookhaven National Lab., Upton, NY (United States)]|[Virginia Polytechnic Institute & State Univ., Blacksburg, VA (United States). Dept. of Physics

1994-06-01T23:59:59.000Z

494

The dynamics of laser droplet generation  

E-Print Network [OSTI]

We propose an experimental setup allowing for the characterization of laser droplet generation in terms of the underlying dynamics, primarily showing that the latter is deterministically chaotic by means of nonlinear time series analysis methods. In particular, we use a laser pulse to melt the end of a properly fed vertically placed metal wire. Due to the interplay of surface tension, gravity force and light-metal interaction, undulating pendant droplets are formed at the molten end, which eventually completely detach from the wire as a consequence of their increasing mass. We capture the dynamics of this process by employing a high-speed infrared camera, thereby indirectly measuring the temperature of the wire end and the pendant droplets. The time series is subsequently generated as the mean value over the pixel intensity of every infrared snapshot. Finally, we employ methods of nonlinear time series analysis to reconstruct the phase space from the observed variable and test it against determinism and stationarity. After establishing that the observed laser droplet generation is a deterministic and dynamically stationary process, we calculate the spectra of Lyapunov exponents. We obtain a positive largest Lyapunov exponent and a negative divergence, i.e., sum of all the exponents, thus indicating that the observed dynamics is deterministically chaotic with an attractor as solution in the phase space. In addition to characterizing the dynamics of laser droplet generation, we outline industrial applications of the process and point out the significance of our findings for future attempts at mathematical modeling.

Blaz Krese; Matjaz Perc; Edvard Govekar

2010-03-01T23:59:59.000Z

495

World Best Practice Energy Intensity Values for Selected Industrial Sectors  

E-Print Network [OSTI]

world best practice energy intensity values for productionWorld best practice energy intensity values for productionWorld Best Practice Final Energy Intensity Values for Aluminium Production (

Worrell, Ernst; Price, Lynn; Neelis, Maarten; Galitsky, Christina; Zhou, Nan

2007-01-01T23:59:59.000Z

496

World Best Practice Energy Intensity Values for Selected Industrial Sectors  

E-Print Network [OSTI]

Best Practice Final Energy Intensity Values for Stand-AloneBest Practice Final Energy Intensity Values for Stand-AloneBest Practice Primary Energy Intensity Values for Stand-

Worrell, Ernst; Price, Lynn; Neelis, Maarten; Galitsky, Christina; Zhou, Nan

2007-01-01T23:59:59.000Z

497

OMEGA EP Laser Dedication Movie - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dedication Movie - Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to...

498

Chirped Laser Dispersion Spectroscopy with Directly Modulated Quantum Cascade Laser  

Science Journals Connector (OSTI)

A feasibility study of chirped laser dispersion spectroscopy (CLaDS) with utilizing direct modulation of a quantum cascade laser instead of external modulators is presented....

Hangauer, Andreas; Spinner, Georg; Nikodem, Michal; Wysocki, Gerard

499

Documentation - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Daily Securing Checklist (S-AB-P-482) EP Bay and OAA Securing Walkthrough (S-AB-P-582) Laser StartupShutdown LOTF Laser Startup (S-AB-P-038) LOTF Laser Shutdown (S-AB-P-039) IRAT...

500