Download or read book Grazing Incidence Pumped Zr X ray Laser for Spectroscopy on Li like Ions written by Daniel Ursescu and published by . This book was released on 2006 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Grazing Incidence Pumped Zr X ray Laser for Spectroscopy on Li like Ions written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray laser fluorescence spectroscopy of the 2s-2p transition in Li-like ions is promising to become a widely applicable tool to provide information on the nuclear charge radii of stable and radioactive isotopes. For performing such experiments at the Experimental Storage Ring ESR, and the future NESR within the FAIR Project, a grazing incidence pumped (GRIP) x-ray laser (XRL) was set up at GSI Darmstadt using PHELIX (Petawatt High Energy Laser for heavy Ions eXperiments). The experiments demonstrated that lasing using the GRIP geometry could be achieved with relatively low pump energy, a prerequisite for higher repetition rate. In the first chapter the need of a plasma XRL is motivated and a short history of the plasma XRL is presented. The distinctive characteristic of the GRIP method is the controlled deposition of the pump laser energy into the desired plasma density region. While up to now the analysis performed were mostly concerned with the plasma density at the turning point of the main pump pulse, in this thesis it is demonstrated that also the energy deposition is significantly modified for the GRIP method, being sensitive in different ways to a large number of parameters. In the second chapter, the theoretical description of the plasma evolution, active medium and XRL emission properties are reviewed. In addition an innovative analysis of the laser absorption in plasma which includes an inverse Bremsstrahlung (IB) correction factor is presented. The third chapter gives an overview of the experimental set-up and diagnostics, providing an analytical formula for the average and instantaneous traveling wave speed generated with a tilted, on-axis spherical mirror, the only focusing system used up to now in GRIP XRL. The fourth chapter describes the experimental optimization and results. The emphasis is on the effect of the incidence angle of the main pump pulse on the absorption in plasma and on output and gain in different lasing lines. This is compared to th.
Download or read book X Ray Lasers 2006 written by P.V. Nickles and published by Springer Science & Business Media. This book was released on 2008-01-18 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: The search for table-top and repetitive pump schemes during the last decade has been the driving force behind the spectacular advances demonstrated during the 10th International Conference on X-Ray Lasers, organized in 2006 in Berlin. The proceedings of this series of conferences constitute a comprehensive source of reference of the acknowledged state-of the-art in this specific area of laser and plasma physics.
Download or read book Grazing Incidence Pumping for Efficient X ray Lasers written by R. F. Smith and published by . This book was released on 2004 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report progress in developing efficient pumping of laser-driven x-ray lasers that opens new possibilities for both high average power x-ray lasers as well as producing progressively shorter wavelength lasers. The new scheme of grazing incidence pumping (GRIP) is described. In essence, a chosen electron density region of a pre-formed plasma column, produced by a longer pulse at normal incidence onto a slab target, is selectively pumped by focusing the short pulse {approx}ps laser at a determined grazing incidence angle to the target. The controlled use of refraction of the pumping laser in the plasma results in several benefits: The pump laser path length is longer and there is an increase in the laser absorption in the gain region for creating a collisional Ni-like ion x-ray laser. There is also an inherent traveling wave, close to c, that increases the overall pumping efficiency. The scheme requires careful tailoring of the pump and plasma conditions to the specific x-ray laser under investigation but the main advantage is a 3 - 30 times reduction in the laser pump energy for mid-Z materials. We report several examples of this new x-ray laser on two different laser systems. The first demonstrates a 10 Hz x-ray laser operating at 18.9 nm pumped with a total of 150 mJ of 800 nm wavelength from a Ti:Sapphire laser. The second case is shown where the COMET laser is used both at 527 nm and 1054 nm wavelength to pump higher Z materials with the goal of extending the wavelength regime of tabletop x-ray lasers below 10 nm.
Download or read book Grazing Incidence Pumping for High Efficiency X ray Lasers written by J. Dunn and published by . This book was released on 2005 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade, most laser-driven collisional excitation x-ray lasers have relied on the absorption of the pump energy incident at normal incidence to a pre-formed plasma. The main advantage is that the inversion can be created at various plasma regions in space and time where the amplification and ray propagation processes are best served. The main disadvantage is that different plasma regions regardless of the contribution to the inversion have to be pumped simultaneously in order to make the laser work. This leads to a loss of efficiency. The new scheme of grazing incidence pumping (GRIP) addresses this issue. In essence, a chosen electron density region of a pre-formed plasma column, produced by a longer pulse at normal incidence onto a slab target, is selectively pumped by focusing a short pulse of 100 fs-10 ps duration laser at a determined grazing incidence angle to the target surface. The exact angle is dependent on the pump wavelength and relates to refraction of the drive beam in the plasma. The controlled use of refraction of the pumping laser in the plasma results in several benefits: The pump laser path length is longer and there is an increase in the laser absorption in the gain region for creating a collisional Ni-like ion x-ray laser. There is also an inherent traveling wave, close to c, that increases the overall pumping efficiency. This can lead to a 3-30 times reduction in the pump energy for mid-Z, sub-20 nm lasers. We report several examples of this new x-ray laser on two different laser systems. The first demonstrates a 10 Hz x-ray laser operating at 18.9 nm pumped with a total of 150 mJ of 800 nm wavelength from a Ti:Sapphire laser. The second case is shown where the COMET laser is used both at 527 nm and 1054 nm wavelength to pump higher Z materials with the goal of extending the wavelength regime of tabletop x-ray lasers below 10 nm.
Download or read book X ray Lasers written by and published by . This book was released on 1990 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EBIT X ray Spectroscopy Studies for Applications to Photo pumped X ray Lasers written by and published by . This book was released on 1994 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several pumping mechanisms have been suggested for x-ray lasers including collisional excitation, recombination, photo-ionization and photo-pumping. The success of photo-pumping as an x-ray laser scheme hinges on sufficient overlap of the emission and adsorption lines. For such a scheme to exhibit gain, the difference of the energies of the two lines must be within the line widths determined by the plasma dynamics, such as Doppler and opacity broadening. Typically, an overlap of a few parts in 104 is required. Due to correlation effects, high-n levels of multi-electron ions are difficult to calculate and are reliable to roughly a part in 103. These differences are large enough to preclude accurate predictions of successful overlaps. As a result, precise measurements of the overlaps are needed. The continued interest in photo-pumping schemes lies in its potential to improve the laser output. It also allows the excitation of lasing transitions not accessible to other mechanisms and thus to the test laser kinetics from a different perspective. We have studied several such photo-pumping schemes at the LLNL electron beam ion trap. The N-like isoelectronic sequence 3d-5f and 3d-6f transitions were studied for photo-pumping by He-like ions, the Ne-like 2p-4d transitions were studied for photo-pumping by N-like 3d-4f transitions, and Ni-like 3d52-6f--2 transitions were studied for photo-pumping by H-like Ly-[alpha] transitions. A number of other chance coincidence pairs which do not follow an isoelectronic sequence were also studied. The data were taken with a flat-crystal vacuum spectrometer, a flat-crystal helium atmosphere spectrometer, or a curved-crystal spectrometer in the von Hamos geometry. The advantage of EBIT over laser-produced or tokamak plasmas for such experiments is its ability to control the charge balance and the excitation process. By choosing the electron beam energy, we can select a dominant charge state.
Download or read book High Repetition Rate Grazing Incidence Pumped X ray Laser Operating at 18 9 Nm written by and published by . This book was released on 2004 with total page 103901 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have demonstrated a 10 Hz Ni-like Mo X-ray laser operating at 18.9 nm with 150 mJ total pump energy by employing a novel pumping scheme. The grazing incidence scheme is described, where a picosecond pulse is incident at a grazing angle to a Mo plasma column produced by a slab target irradiated by a 200 ps laser pulse. This scheme uses refraction of the short pulse at a pre-determined electron density to increase absorption to pump a specific gain region. The high efficiency inherent to this scheme allows a reduction in the pump energy where 70 mJ long pulse energy and 80 mJ short pulse energy are sufficient to produce lasing at a 10 Hz repetition rate. Under these conditions and by optimizing the delay between the pulses, we achieve strong amplification and saturation for 4 mm long targets.
Download or read book Characterization and Optimization of an X ray Laser for the Spectroscopy of Li like Heavy ions written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent developments in the theory of plasma-based collisionally excited x-ray lasers (XRL) have shown an optimization potential based on the dependence of the absorption region of the pumping laser on its angle of incidence on the plasma. For the experimental proof of this idea, a number of diagnostic schemes were developed, tested, qualified and applied. A high-resolution imaging system, yielding the keV emission profile perpendicular to the target surface, provided positions of the hottest plasma regions, interesting for the benchmarking of plasma simulation codes. The implementation of a highly efficient spectrometer for the plasma emission made it possible to gain information about the abundance of the ionization states necessary for the laser action in the plasma. The intensity distribution and deflection angle of the pump laser beam could be imaged for single XRL shots, giving access to its refraction process within the plasma. During a European collaboration campaign at the Lund Laser Center, Sweden, the optimization of the pumping laser incidence angle resulted in a reduction of the required pumping energy for a Ni-like Mo XRL, which enabled the operation at a repetition rate of 10 Hz. Using the experiences gained there, the XRL performance at the PHELIX facility, GSI Darmstadt with respect to achievable repetition rate and at wavelengths below 20 nm was significantly improved, and also important information for the development towards multi-100 eV plasma XRLs was acquired. Due to the setup improvements achieved during the work for this thesis, the PHELIX XRL system now has reached a degree of reproducibility and versatility which is sufficient for demanding applications like the XRL spectroscopy of heavy ions. In addition, a European research campaign, aiming towards plasma XRLs approaching the water-window (wavelengths below 5 nm) was initiated.
Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A 10 Hz Grazing Incidence Pumped Ni like Mo Laser at 18 9 Nm with 150 MJ Pump Energy written by R. F. Smith and published by . This book was released on 2004 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first demonstration of the grazing incidence pumping (GRIP) scheme for laser-driven x-ray lasers (XRLs) is described utilizing 2-pulse pumping. A long pulse is incident normal to the target to produce a plasma with a particular density profile. Then a short pulse is incident at a grazing angle, chosen to optimally couple the short pulse laser energy into the specific density region where the inversion process will occur. The short pulse is simultaneously absorbed and refracted at a maximum electron density specified by the chosen pump angle then turns back into the gain region. The increased path length gives improved absorption allowing a reduction in the drive energy required for lasing. A Ni-like Mo XRL at 18.9 nm has been demonstrated with only 150 mJ total pump energy and a repetition rate of 10 Hz. We report high gains of 60 cm{sup -1} and the achievement of gain saturation for targets of 4 mm length.
Download or read book X ray Lasers from Collisionally pumped Nickel like Ions written by Riccardo Tommasini and published by . This book was released on 1999 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization and Optimization of an X ray Laser for the Spectroscopy of Li like Heavy ions written by Bernhard Zielbauer and published by . This book was released on 2007 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Science Abstracts written by and published by . This book was released on 1993 with total page 948 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optics Index written by and published by . This book was released on 1990 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fusion Energy Update written by and published by . This book was released on 1985 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synchrotron Light Sources and Free Electron Lasers written by Eberhard J. Jaeschke and published by Springer. This book was released on 2016-05-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hardly any other discovery of the nineteenth century did have such an impact on science and technology as Wilhelm Conrad Röntgen’s seminal find of the X-rays. X-ray tubes soon made their way as excellent instruments for numerous applications in medicine, biology, materials science and testing, chemistry and public security. Developing new radiation sources with higher brilliance and much extended spectral range resulted in stunning developments like the electron synchrotron and electron storage ring and the freeelectron laser. This handbook highlights these developments in fifty chapters. The reader is given not only an inside view of exciting science areas but also of design concepts for the most advanced light sources. The theory of synchrotron radiation and of the freeelectron laser, design examples and the technology basis are presented. The handbook presents advanced concepts like seeding and harmonic generation, the booming field of Terahertz radiation sources and upcoming brilliant light sources driven by laser-plasma accelerators. The applications of the most advanced light sources and the advent of nanobeams and fully coherent x-rays allow experiments from which scientists in the past could not even dream. Examples are the diffraction with nanometer resolution, imaging with a full 3D reconstruction of the object from a diffraction pattern, measuring the disorder in liquids with high spatial and temporal resolution. The 20th century was dedicated to the development and improvement of synchrotron light sources with an ever ongoing increase of brilliance. With ultrahigh brilliance sources, the 21st century will be the century of x-ray lasers and their applications. Thus, we are already close to the dream of condensed matter and biophysics: imaging single (macro)molecules and measuring their dynamics on the femtosecond timescale to produce movies with atomic resolution.
