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In 2009, the Savannah Sports Council hosted its 11 annual Savannah Hockey Classic. In order to assist the future marketing of this event, a study was undertaken to assist the Savannah Sports Council in 3 major ways: (1) To obtain a consumer profile of spectators, (2) to explore the economic impact of the event on the city of Savannah, and (3) to discover the perceived personality of the event (assist in sponsor recruitment). To reach the objectives of the study, a survey was conducted with 267 spectators of the Savannah Hockey Classic. The survey consisted of four sections: (1) Economic impact (2) Consumer behavior & preferences, (3) Attitude and image perceptions of the event and organizing body, and (4) Consumer demographic characteristics. The majority of respondents were male (62%) and Caucasian (95%). While their average age was 36, 78% of respondents were between the ages of 25 to 59. Spectators tended to be educated (61% with a college degree of some sort) and affluent (63% earn > $50,000). Just over half (56%) of the spectators traveled to Savannah to attend the event. Eighty-one of the eighty-three out-of-town respondents reported spending at least 1 night in Savannah. However, 50% of out-of-town respondents said they would have come to Savannah even if the Hockey Classic was not taking place. Eighty-two percent said they would be visiting Savannah at some point in the following 3 months. This suggests that while the Hockey Classic is a popular event, most of the visitors would travel to Savannah even if the event did not take place. Spectators appear to have developed very positive feelings about the Savannah Hockey Classic. On a 7-point scale, respondents reported the following scores on a variety of items: Gratitude toward the Savannah Sports Council for organizing the event was very high 6.5, attitude regarding the success and quality of the hockey event itself was 6.4, and fan identification with the event was reported at 6.1. With regard to the image/brand of the event, respondents perceive the Hockey Classic to be: An exciting event (6.4 out of 7), a sincere/wholesome event (6.3 out of 7), and a competent and successful event (6.3 out of 7). 1 Dees and Hall: Savannah Hockey Classic: An Evaluation of Event Personality and E Published by ScholarWorks@GVSU, 2010 Journal of Tourism Insight s Vol. 1 No. 1 46 visitor-related transportation account for over $2 billion in visitors' spending per year and employ over 17,000 people (Savannah Convention & Visitors Bureau, 2006). Savannah also boasts many sports entertainment options for visitors to this beautiful and historic area. The Greater Savannah Sports Council (GSSC) is an organization that seeks to increase sports activity and spending in the area by marketing and promoting many of the local sporting teams and events such as the Savannah Sand Gnats, Enmark Bridge Run, and Savannah Hockey Classic. The purpose of this study was to assist the Savannah Sports Council with their marketing and promotional efforts for the Savannah Hockey Classic (SHC). An evaluation of the event’s personality and local economic impact was conducted in order to aid SHC event coordinators in creating future marketing strategies aimed at generating increased attendance and revenue via the sport tourism industry. The objective of the study was threefold: (1) To obtain a consumer profile of spectators, (2) to explore the economic impact of the event on the city of Savannah, and (3) to discover the perceived personality of the event (assist in sponsor recruitment). Savannah Hockey Classic Background In 2009, the Savannah Sports Council hosted its 11 annual Savannah Hockey Classic. The SHC has been a prominent winter event that has grown in size and popularity every year since its inception. Aside from the inaugural tournament, held in 1999, the four teams participating in the event have included the University of Georgia, Georgia Tech, University of Florida, and Florida State University. Typically, the opening night of the tournament (Friday) showcases the conference rivalries with Georgia competing against Florida and Georgia Tech facing off against Florida State. The home state rivalries are saved for the second night (Saturday) of the event. The Georgia schools have experienced a great deal of success since the tournament’s creation. Only in 2008 did one of the Florida schools win the SHC tournament (FSU). According to WTOC11 (2010) in Savannah: Twelve years this has been going on. And in each of those years, it has grown, including this year [2010] when a third night was added and two more teams brought in to further build on the rivalries that are the heart of the event. But now the Hockey Classic's growth is evident beyond Savannah, the event's identity at least partly responsible for the formation of a new league for SEC teams, the Southeastern Collegiate Hockey Conference. "I think this tournament had a big impact because of the popularity of it," said SECCH commissioner Ken Day, who was part of the Hockey Classic for 11 years as a coach with Georgia Tech. The SHC was held in January, 2009 at the Savannah Civic Center in the heart of downtown Savannah, Georgia. According to their website (Savannah Civic Center, 2010), the Savannah Civic Center is responsible for providing a wide spectrum of entertainment and cultural activities while also hosting conventions, exhibit shows, and social events. The Civic Center currently employs 20 full-time and more than 300 event labor staff. The venue plays host to approximately 900 events annually with a wide variety of entertainment experiences including: WWE & ECW Wrestling, Figure Skating Champions on Ice, Walt Disney on Ice, Ringling Brothers Circus, Best of Broadway Series, concerts and ballet. The Martin Luther King Arena has seating arrangements ranging from 3,500 to 9,600 while the Johnny Mercer Theatre seats 2,506, boasting one of the largest prosceniums in the Southeast. The SHC attracts roughly 10,000 spectators each year to the Savannah Civic Center (9,731 in 2009 and 10,290 in 2010, personal communication from Ben Wilder).

International audience; The electronic structure evolution of highly compressed aluminum has been investigated using timeresolved $K$ edge x-ray absorption spectroscopy. A long laser pulse (500 ps, I$_L$ $\approx$ 8 X 10$^{13}$ W/cm$^2$) wasused to create a uniform shock. A second ps pulse (I$_L$ $\approx$ 10$^{17}$ W/cm$^2$) generated an ultrashort broadbandx-ray source near the Al $K$ edge. The main target was designed to probe aluminum at reshocked conditionsup to now unexplored (3 times the solid density and temperatures around 8 eV). The hydrodynamicalconditions were obtained using rear side visible diagnostics. Data were compared to ${ab}$ ${initio}$ and denseplasma calculations, indicating potential improvements in either description. This comparison shows thatx-ray-absorption near-edge structure measurements provide a unique capability to probe matter at theseextreme conditions and severally constrains theoretical approaches currently used.

We compressed water to megabar pressures by laser-driven shock waves and evidenced transparent, opaque and reflecting phases as pressure increases. The refraction index of water in the first two states was measured using a VISAR system. At high compression a sharp increase of the real and imaginary part of the refraction index is observed. Experiments were performed at the LULI and RAL laboratories.

With the addition of recent PW shots, the propagation of short-pulse laser generated electron beams have been studied using laser pulse energies from 30 J to 300 J, generating currents up to ∼15 MA in solid Al:Cu targets. This is ∼5% of the current that will be required in an ignition pulse. To this level, the current appears to simply scale with laser power, the propagation spread not change at all. The resistance of the aluminum does not seem to play a role in the propagation characteristics, though it might in setting the current starting parameters. We do find that at the highest currents parts of these targets reach temperatures high enough to modify the Cu-K2 emission spectrum rendering our Bragg imaging mirrors ineffective; spectrometers will be needed to collect data at these higher temperatures. © EDP Sciences.

We present the set-up and the results of a supercritical radiative shock experiment performed with the LULI nanosecond laser facility. Using specific designed targets filled with xenon gaz at low pressure, the propagation of a strong shock with a radiative precursor is evidenced. The main measured quantities related to the shock (electronic density, propagation velocities, temperature, radial dimension) are presented and compared with various numerical simulations.

International audience; This paper reports the results of some recent experiments performed at the LULI laboratory (Palaiseau, France) concerning the propagation of large relativistic electron currents in a gas jet. We present our experimental results according to the type of diagnostics used in the experiments: (1) time resolved optical shadowgraphy and (2) proton imaging. Proton radiography images did show the presence of very strong fields in the gas probably produced by charge separation. In turn, these imply a slowing down of the fast electron cloud as it penetrates in the gas. Indeed, shadowgraphy images show a strong inhibition of propagation and a strong reduction in time of the velocity of the electron cloud from the initial value, which is of the order of a fraction of c.

Experiments on the Equation of State (EOS) of Carbon were performed at the PALS and LULl laboratories. We used Carbon samples with two different value of initial density, in order to explore a wider region of the phase diagram. We obtain experimental data for carbon Hugoniot at Megabar pressures induced by laser-driven shock waves. The target rear side eniissivity due to the shock unloading was recorded from > targets (Al-C) with space and time resolution. By applying the impedance mismatch method, a direct determination of relative EOS points was obtained. Experimental data are compared with previous experiments and with theoretical models. Our results indicate a higher compressibility of carbon at Megabar pressures compared to theoretical models.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Electron transport within solid targets, irradiated by a high-intensity short-pulse laser, has been measured by imaging ${K}_{\ensuremath{\alpha}}$ radiation from high-$Z$ layers (Cu, Ti) buried in low-$Z$ (CH, Al) foils. Although the laser spot is $\ensuremath{\sim}10\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$ [full width at half maximum (FWHM)], the electron beam spreads to $\ensuremath{\geqslant}70\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$ FWHM within $l20\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$ of penetration into an Al target then, at depths $g100\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$, diverges with a $40\ifmmode^\circ\else\textdegree\fi{}$ spreading angle. Monte Carlo and analytic models are compared to our data. We find that a Monte Carlo model with a heuristic model for the electron injection gives a reasonable fit with our data.

International audience; We study the propagation of fast electrons in a gas at different densities. A large relativistic electron current is produced by focusing a short-pulse ultrahigh-intensity laser on a metallic target. It then propagates in a gas jet placed behind the foil. Shadowgraphy in the gas shows an electron cloud moving at sub-relativistic average velocities. The experiment shows (i) the essential role of the density of background material for allowing propagation of fast electrons, (ii) the importance of the ionization phase which produces free electrons available for the return current, and (iii) the effect of electrostatic fields on fast-electron propagation.

We present an experimental point for the carbon equation of state (EOS) at megabar pressures, obtained by laser-driven shock waves. The rear side emissivity of "two-materials two-steps" targets (Al-C) was recorded with space and time resolution and, by applying the impedance mismatch method, allowed a direct determination of relative EOS points. Experiments were performed at the PALS and LULI laboratories using carbon samples with two different values of initial density, in order to explore a wider region of the phase diagram. Previously unreached pressures were obtained. The results are compared with previous experiments and with available theoretical models and seem to show a high compressibility of carbon at megabar pressures.

In this article, we present a laboratory astrophysics experiment on radiative shocks and its interpretation using simple modelization. The experiment is performed with a 100-J laser (pulse duration of about 0.5 ns) which irradiates a 1-mm3 xenon gas-filled cell. Descriptions of both the experiment and the associated diagnostics are given. The apparition of a radiation precursor in the unshocked material is evidenced from interferometry diagrams. A model including self-similar solutions and numerical ones is derived and fairly good agreements are obtained between the theoretical and the experimental results.

Rapid heating of a compressed fusion fuel by a short-duration laser pulse is a promising route to generating energy by nuclear fusion, and has been demonstrated on an experimental scale using a novel fast-ignitor geometry. Here we describe a refinement of this system in which a much more powerful, pulsed petawatt (10(15) watts) laser creates a fast-heated core plasma that is scalable to full-scale ignition, significantly increasing the number of fusion events while still maintaining high heating efficiency at these substantially higher laser energies. Our findings bring us a step closer to realizing the production of relatively inexpensive, full-scale fast-ignition laser facilities.

We report on rear-side optical self-emission results from ultraintense laser pulse interactions with solid targets. A prompt emission associated with a narrow electron jet has been observed up to aluminum target thicknesses of 400 microm with a typical spreading half-angle of 17 degrees. The quantitative results on the emitted energy are consistent with models where the optical emission is due to transition radiation of electrons reaching the back surface of the target or due to a synchrotron-type radiation of electrons pulled back to the target. These models associated with transport simulation results give an indication of a temperature of a few hundred keV for the fast-electron population.

We present equation of state points for iron, in the pressure range 10-45 Mbar, the first obtained with laser-driven shock waves. The experiment has been performed with the high energy laser Phebus, optically smoothed with Kinoform phase plates. Our results double the set of existing experimental data at very high pressures showing good agreement with the predictions of the quotidian equation of state model and with previous results.

The transport of relativistic electrons in solid targets irradiated by a short laser pulse at relativistic intensities has been studied both experimentally and numerically. A Monte‐Carlo collision code takes into account individual collisions with the ions and electrons in the target. A 3D‐hybrid code takes into account these collisions as well as the generation of electric and magnetic fields and the self‐consistent motion of the electrons in these fields. It predicts a magnetic guiding of a fraction of the fast electron current over long distances and a localized heating of the material along the propagation axis. In experiments performed at LULI on the 100 TW laser facility, several diagnostics have been implemented to diagnose the geometry of the fast electron transport and the target heating. The typical conditions were: E1 ⩽ 20 J, λ = 1 μm, τ ≈ 300 fs, I ≈ 1018−5.1019W/cm2. The results indicate a modest heating of the target (typically 20–40 eV over 20 μm to 50 μm), consistent with an acceleration of the electrons inside a wide aperture cone along the laser axis.

In recent years, shock waves driven by high power lasers have become a reliable tool for the study of the equation of state (EOS) of material sin the Megabar pressure range, where they become strongly correlated, degenerate, dense plasmas. The EOS of water at very high pressures plays a very important role in astrophysics. In particular, the large magnetic field measured on Uranus and Neptune by Voyager 2 is assumed to be generated in the 'ice' layers where pressures up to 6 Mbar are reached. Recent calculations predict an insulator-metallic phase transition of water in this regime. Here, we present some preliminary results form a recent experiment on water EOS performed with the laser PHEBUS and funded by the European Union in the framework of the 'Access to Large Scale Facilities' program. In the experiment, structured targets made of an Aluminium step followed by a water layer are irradiated by the laser at an intensity approximately equals 4.1014 W.cm-2 to generate a shock wave. Velocities are measured in the two materials using a VISAR interferometric diagnostic for water, and a streak camera to measure target emission for Al. EOS points for water are obtained with the impedance mismatch method using Al EOS as a reference. Water reflectivity was also measured.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Experimental results are reported on transport through a solid target of fast-electrons created by an ultra-intense laser pulse interaction. In particular, the goal was to determine the heating induced in the material by the fast electrons. Such a study is of great interest within the context of the Fast Igniter [1] approach to Inertial Confinement Fusion, where the heating needed to ignite nuclear reactions is supposed to be achieved by a sub-ps fast electron bunch. Experimentally, the main point is therefore to observe the propagation geometry of the fast electron beam and to estimate the amount of energy which can be carried and deposed in dense matter by a given electron source. So far, theory and simulations have not yet provided a complete picture of the prop-agation phenomena. Therefore, experimental work is requried in order to understand and dis crimed the basic processes involved.

Fast electron generation and propagation were studied in the interaction of a green laser with solids. The experiment, carried out with the LULI TW laser (350 fs, 15 J), used ${K}_{\ensuremath{\alpha}}$ emission from buried fluorescent layers to measure electron transport. Results for conductors (Al) and insulators (plastic) are compared with simulations: in plastic, inhibition in the propagation of fast electrons is observed, due to electric fields which become the dominant factor in electron transport.

The BL Lacertae object Markarian 501 was identified as a source of gamma-ray emission at the Whipple Observatory in March 1995. Here we present a flux variability analysis on several times-scales of the 233 hour data set accumulated over 213 nights (from March 1995 to July 1998) with the Whipple Observatory 10 m atmospheric Cherenkov imaging telescope. In 1995, with the exception of a single night, the flux from Markarian 501 was constant on daily and monthly time-scales and had an average flux of only 10% that of the Crab Nebula, making it the weakest VHE source detected to date. In 1996, the average flux was approximately twice the 1995 flux and showed significant month-to-month variability. No significant day-scale variations were detected. The average gamma-ray flux above ~350 GeV in the 1997 observing season rose to 1.4 times that of the Crab Nebula -- 14 times the 1995 discovery level -- allowing a search for variability on time-scales shorter than one day. Significant hour-scale variability was present in the 1997 data, with the shortest, observed on MJD 50607, having a doubling time of ~2 hours. In 1998 the average emission level decreased considerably from that of 1997 (to ~20% of the Crab Nebula flux) but two significant flaring events were observed. Thus, the emission from Markarian 501 shows large amplitude and rapid flux variability at very high energies as does Markarian 421. It also shows large mean flux level variations on year-to-year time-scales, behaviour which has not been seen from Markarian 421 so far., 19 pages, 3 figures, to appear in ApJ, June 20, 1999, Vol. 518 #2

We performed the first experimental study of propagation in compressed matter of hot electrons created by a short pulse intense laser. The experiment has been carried out with the VULCAN laser at Rutherford compressing plastic targets with two ns laser beams at an intensity ⩾1014 W/cm2. A CPA beam with an intensity ⩾1016 W/cm2 irradiated the rear side of the target and created hot electrons propagating through the compressed matter. K‐α emission was used as diagnostics of hot electron penetration by putting a chloride plastic layer inside the target.

This paper describes the generation of very-high pressures shocks by means of laser beams, and their use for Equation-of-State experiments on materials in the Megabar pressure ranges. In particular, we present some applications to the study of EOS of carbon. Finally, we discuss non-equilibrium processes in laser-driven shocks.

We present a control system, which allows an automatic optimization of the pulse train stability in a mode-locked laser cavity. In order to obtain real-time corrections, we chose a closed loop approach. The control variable is the cavity length, mechanically adjusted by gear system acting on the rear cavity mirror, and the controlled variable is the envelope modulation of the mode-locked pulse train. Such automatic control system maintains the amplitude of the mode-locking pulse train stable within a few percent rms during the working time of the laser. Full implementation of the system on an Nd:yttrium lithium fluoride actively mode-locked laser is presented.

Harmonics of the laser light have been observed from the rear side of solid targets irradiated by a laser beam at relativistic intensities. This emission evidences the acceleration of subfemtosecond electron bunches by the laser pulse in front of the target. These bunches emit coherent transition radiation (CTR) when passing through the back surface of the target. The spectral features of the signal recorded for targets of thicknesses up to several hundred microns are consistent with the electrons being accelerated by both the laser electric field—via vacuum heating and/or resonance absorption,—and the v×B component of the Lorentz force. The spatial study of the radiation shows that the relativistic electrons causing the CTR radiation are coherent and propagate ballistically through the target, originating from a source with a size of the order of the laser focal spot.

The second harmonic of the laser light ($2{\ensuremath{\omega}}_{0}$) is observed on the rear side of thick solid targets irradiated by a laser beam at relativistic intensities. This emission is explained by the acceleration by the laser pulse in front of the target of short bunches of electrons separated by the period (or half the period) of the laser light. When reaching the rear side of the target, these electron bunches emit coherent transition radiation at $2{\ensuremath{\omega}}_{0}$. The observations indicate that, in our conditions, the minimum fraction of the laser energy transferred to these electron bunches is of the order of 1%.

High power lasers are nowadays tools that can be used to simulate some astrophysical phenomena. In this experiment, the physical parameters have been chosen in order to reproduce radiative shock conditions. The targets were made of a small cell (1 mm3) filled with Xenon at low pressure (< 1 atm). On the laser side, we had a three layers pusher optimized for reaching conditions where the launched shock in Xe is radiative. Rear side and transverse diagnostics allowed to determine shock and precursor velocities, electronic density along the shock propagation. Comparison with numerical simulations and models are presented. These experiments were performed with the LULI laser.