692 research outputs found
Lâaccueil en France des longs mĂ©trages hollywoodiens en relief (1952-1955)
Le 26 novembre 1952 sort Ă Los Angeles le long mĂ©trage Bwana Devil, film partiellement rĂ©alisĂ© en relief, dont le succĂšs rouvre alors la perspective dâun cinĂ©ma stĂ©rĂ©oscopique. Entre cette date et novembre 1954, soixante-deux films sont rĂ©alisĂ©s et distribuĂ©s en relief aux Etats-Unis. Trente de ces films, tous des longs mĂ©trages, sont distribuĂ©s en France Ă partir dâavril 1953. Cet article analyse lâaccueil de ces longs mĂ©trages et, par leur biais, de leur technologie mĂȘme par les professionnels et le public français. Il montre que le relief de Hollywood nâa exercĂ© sur ces derniers quâun bref attrait et tente de mettre en perspective les multiples facteurs de lâĂ©chec de cette aventure technique qui contribua nĂ©anmoins Ă introduire un renouvellement du spectacle cinĂ©matographique en France.On 26 November 1952, Bwana Devil , a feature length film partially made in 3-D, was released in Los Angeles. Its success revives the idea of stereoscopic cinema. Over the next two years, sixty-two 3-D films are made and distributed in the USA. Thirty of them, all feature films, are released in France, from April 1953 onwards. This article analyses how these films and, by extension, their technology were received both by film professionals and the French public. It shows that Hollywood 3-D had only a short-lived appeal in France, and aims to put in perspective the many reasons for the failure of this technical experiment, which nonetheless contributed to a revival of the film spectacle in France
« Le Film sur lâart, entre histoire de lâart et documentaire de crĂ©ation »
Du 14 au 16 avril 2011 a eu lieu, Ă la section dâHistoire et esthĂ©tique du cinĂ©ma de lâUniversitĂ© de Lausanne, un colloque international intitulĂ© « Le film sur lâart, entre histoire de lâart et documentaire de crĂ©ation ». Ce colloque, dirigĂ© par François Albera, Kornelia Imesch, Laurent Le Forestier, Mario LĂŒscher et Valentine Robert, Ă©tait coorganisĂ© par trois sections de lâUniversitĂ© de Lausanne (Sciences historiques de la culture, Histoire de lâart, Histoire et esthĂ©tique du cinĂ©ma) et par..
Des parents italiens pour les Enfants du Paradis
Beaucoup de lĂ©gendes entourent la production des Enfants du Paradis. FondĂ© sur lâexploration dâarchives peu Ă©tudiĂ©es, cet article vise Ă mettre au jour une rĂ©alitĂ© plus complexe en replaçant lâhistoire du film dans un triple contexte. Dâabord celui des stratĂ©gies de pĂ©nĂ©tration du cinĂ©ma français par les Italiens durant lâOccupation. Ensuite les activitĂ©s du producteur AndrĂ© PaulvĂ© Ă la tĂȘte des studios de Nice pendant cette pĂ©riode. Enfin le rĂŽle jouĂ© en Italie et en France par la sociĂ©tĂ© Scalera Film au mĂȘme moment. Il en ressort que les restrictions imposĂ©es au cinĂ©ma français de lâOccupation ont obligĂ© PaulvĂ© Ă proposer Ă la firme italienne Scalera de devenir le producteur des Enfants du Paradis. Pour cette raison, câest lâarmistice sĂ©parĂ© signĂ© par les Italiens qui a provoquĂ© en septembre 1943 lâinterruption du tournage. La reprise de la production par PathĂ©-CinĂ©ma a Ă©tĂ© ensuite fortement encouragĂ©e par les Pouvoirs publics français. DĂšs avant la sortie du film, un discours consensuel sâest immĂ©diatement constituĂ© pour faire de celui-ci une sorte dâemblĂšme de la RĂ©sistance nationale, au prix dâun certain nombre de distorsions de la vĂ©ritĂ© historique largement nourries par les dĂ©clarations de Marcel CarnĂ©.There are many legends around the production of Marcel CarnĂ©âs Les Enfants du Paradis. Using little known archival sources, this article aims to reveal the hitherto unknown and more complex reality by exploring three questions. First, the strategies developed by the Italians to penetrate the French film industry during the Occupation. Second, the actions of producer AndrĂ© PaulvĂ© as head of the Nice film studios. Third, the part played by the company Scalera Film in Italy and in France at that time. From this analysis it appears that the restrictions imposed upon the French film industry during the Occupation forced PaulvĂ© to bring in Scalera as the producer of Les Enfants du Paradis, with Italian financing. This is why the production was interrupted in September 1943 when the Italians signed a separate armistice with the Allies. PathĂ© CinĂ©ma then took over the production after much insistence from the French authorities. Even before the film was officially released, a large consensus had been formed, encouraged by CarnĂ© himself, to present it as a testimony to French national Resistance
The Dragonfly Galaxy. III. Jet-brightening of a High-redshift Radio Source Caught in a Violent Merger of Disk Galaxies
The Dragonfly Galaxy (MRC 0152-209), the most infrared-luminous radio galaxy
at redshift z~2, is a merger system containing a powerful radio source and
large displacements of gas. We present kpc-resolution data from ALMA and the
VLA of carbon monoxide (6-5), dust, and synchrotron continuum, combined with
Keck integral-field spectroscopy. We find that the Dragonfly consists of two
galaxies with rotating disks that are in the early phase of merging. The radio
jet originates from the northern galaxy and brightens when it hits the disk of
the southern galaxy. The Dragonfly Galaxy therefore likely appears as a
powerful radio galaxy because its flux is boosted into the regime of high-z
radio galaxies by the jet-disk interaction. We also find a molecular outflow of
(1100 550) M/yr associated with the radio host galaxy, but not
with the radio hot-spot or southern galaxy, which is the galaxy that hosts the
bulk of the star formation. Gravitational effects of the merger drive a slower
and longer lived mass displacement at a rate of (170 40) M/yr,
but this tidal debris contain at least as much molecular gas mass as the much
faster outflow, namely M(H2) = (3 1) x 10 (alpha(CO)/0.8)
M. This suggests that both the AGN-driven outflow and mass transfer
due to tidal effects are important in the evolution of the Dragonfly system.
The Keck data show Ly emission spread across 100 kpc, and CIV and HeII
emission across 35 kpc, confirming the presence of a metal-rich and extended
circumgalactic medium previously detected in CO(1-0).Comment: Accepted for publication in ApJ (15 pages, 9 figures
ALMA finds dew drops in the dusty spiderâs web
We present 0.Ì5 resolution ALMA detections of the observed 246âGHz continuum, [CI] 3P2â3P1 fine structure line ([CI]2â1), CO(7â6), and H2O lines in the z = 2.161 radio galaxy MRC1138-262, the so-called Spiderweb galaxy. We detect strong [CI]2â1 emission both at the position of the radio core, and in a second component ~4âkpc away from it. The 1100âkmâs-1 broad [CI]2â1 line in this latter component, combined with its H2 mass of 1.6 Ă 1010âMâ, implies that this emission must come from a compact region <60âpc, possibly containing a second active galactic nucleus (AGN). The combined H2 mass derived for both objects, using the [CI]2â1 emission, is 3.3 Ă 1010âMâ. The total CO(7â6)/[CI]2â1 line flux ratio of 0.2 suggests a low excitation molecular gas reservoir and/or enhanced atomic carbon in cosmic ray dominated regions. We detect spatially-resolved H2O 211â202 emission â for the first time in a high-z unlensed galaxy â near the outer radio lobe to the east, and near the bend of the radio jet to the west of the radio galaxy. No underlying 246âGHz continuum emission is seen at either position. We suggest that the H2O emission is excited in the cooling region behind slow (10â40 kmâs-1) shocks in dense molecular gas (103â5 cm-3). The extended water emission is likely evidence of the radio jetâs impact on cooling and forming molecules in the post-shocked gas in the halo and inter-cluster gas, similar to what is seen in low-z clusters and other high-z radio galaxies. These observations imply that the passage of the radio jet in the interstellar and inter-cluster medium not only heats gas to high temperatures, as is commonly assumed or found in simulations, but also induces cooling and dissipation, which can lead to substantial amounts of cold dense molecular gas. The formation of molecules and strong dissipation in the halo gas of MRC1138-262 may explain both the extended diffuse molecular gas and the young stars observed around MRC1138-262
Combined spectroscopy and intensity interferometry to determine the distances of the blue supergiants P Cygni and Rigel
In this paper, we report on the spatial intensity interferometry measurements
within the H line on two stars: the Luminous Blue Variable (LBV)
supergiant \PCygni\,and the late-type B supergiant Rigel. The experimental
setup has been upgraded to allow simultaneous measurement of two polarization
channels and the zero baseline correlation function. Combined with simultaneous
spectra measurements and based on radiative transfer models calculated with the
code CMFGEN, we were able to fit our measured visibility curves to extract the
stellar distances. Our distance determinations for both \PCygni\ (1.61
0.18 kpc) and Rigel (0.26 0.02 kpc) agree very well with the values
provided by astrometry with the Gaia and Hipparcos missions, respectively. This
is the first successful step towards extending the application of the Wind
Momentum Luminosity Relation method for distance calibration from an LBV
supergiant to a more normal late-type B supergiant
3D tomography of the giant Lyα nebulae of z â 3â5 radio-loud AGN
Lyα emission nebulae are ubiquitous around high-redshift galaxies and are tracers of the gaseous environment on scales out to âł100 pkpc (proper kiloparsec). High-redshift radio galaxies (HzRGs, type-2 radio-loud quasars) host large-scale nebulae observed in the ionised gas differ from those seen in other types of high-redshift quasars. In this work, we exploit MUSE observations of Lyα nebulae around eight HzRGs (2.92â<âzâ<â4.51). All of the HzRGs have large-scale Lyα emission nebulae with seven of them extended over 100 pkpc at the observed surface brightness limit (âŒ2â
ââ
20â
Ăâ
10â19âergâsâ1âcmâ2âarcsecâ2). Because the emission line profiles are significantly affected by neutral hydrogen absorbers across the entire nebulae extent, we performed an absorption correction to infer maps of the intrinsic Lyα surface brightness, central velocity, and velocity width, all at the last scattering surface of the observed Lyα photons. We find the following: (i) that the intrinsic surface brightness radial profiles of our sample can be described by an inner exponential profile and a power law in the low luminosity extended part; (ii) our HzRGs have a higher surface brightness and more asymmetric nebulae than both radio-loud and radio-quiet type-1 quasars; (iii) intrinsic nebula kinematics of four HzRGs show evidence of jet-driven outflows but we find no general trends for the whole sample; (iv) a relation between the maximum spatial extent of the Lyα nebula and the projected distance between the active galactic nuclei (AGN) and the centroids of the Lyα nebula; and (v) an alignment between radio jet position angles and the Lyα nebula morphology. All of these findings support a scenario in which the orientation of the AGN has an impact on the observed nebular morphologies and resonant scattering may affect the shape of the surface brightness profiles, nebular kinematics, and relations between the observed Lyα morphologies. Furthermore, we find evidence showing that the outskirts of the ionised gas nebulae may be âcontaminatedâ by Lyα photons from nearby emission halos and that the radio jet affects the morphology and kinematics of the nebulae. Overall, this work provides results that allow us to compare Lyα nebulae around various classes of quasars at and beyond cosmic noon (zââŒâ3)
Single-mode instability in standing-wave lasers: The quantum cascade laser as a self-pumped parametric oscillator
We report the observation of a clear single-mode instability threshold in continuous-wave Fabry-Perot quantum cascade lasers (QCLs). The instability is characterized by the appearance of sidebands separated by tens of free spectral ranges (FSR) from the first lasing mode, at a pump current not much higher than the lasing threshold. As the current is increased, higher-order sidebands appear that preserve the initial spacing, and the spectra are suggestive of harmonically phase-locked waveforms. We present a theory of the instability that applies to all homogeneously broadened standing-wave lasers. The low instability threshold and the large sideband spacing can be explained by the combination of an unclamped, incoherent Lorentzian gain due to the population grating, and a coherent parametric gain caused by temporal population pulsations that changes the spectral gain line shape. The parametric term suppresses the gain of sidebands whose separation is much smaller than the reciprocal gain recovery time, while enhancing the gain of more distant sidebands. The large gain recovery frequency of the QCL compared to the FSR is essential to observe this parametric effect, which is responsible for the multiple-FSR sideband separation. We predict that by tuning the strength of the incoherent gain contribution, for example by engineering the modal overlap factors and the carrier diffusion, both amplitude-modulated (AM) or frequency-modulated emission can be achieved from QCLs. We provide initial evidence of an AM waveform emitted by a QCL with highly asymmetric facet reflectivities, thereby opening a promising route to ultrashort pulse generation in the mid-infrared. Together, the experiments and theory clarify a deep connection between parametric oscillation in optically pumped microresonators and the single-mode instability of lasers, tying together literature from the last 60 years.United States. Defense Advanced Research Projects Agency. Spectral Combs from UV to THz Program (Grant W31P4Q-16-1-0002)National Science Foundation (U.S.) (Awards ECCS-1230477, ECCS-1614631 and ECCS- 1614531)United States. Dept. of Defense. Assistant Secretary of Defense for Research & Engineering (Air Force Contracts FA8721-05-C- 0002 and No. FA8702-15-D-0001
The mysterious morphology of MRC0943-242 as revealed by ALMA and MUSE
© 2016 ESO. We present a pilot study of the z = 2.923 radio galaxy MRC0943-242, where we combine information from ALMA and MUSE data cubes for the first time. Even with modest integration times, we disentangle the AGN and starburst dominated components. These data reveal a highly complex morphology as the AGN, starburst, and molecular gas components show up as widely separated sources in dust continuum, optical continuum, and CO line emission observations. CO(1-0) and CO(8-7) line emission suggest that there is a molecular gas reservoir offset from both the dust and the optical continuum that is located ~90 kpc from the AGN. The UV line emission has a complex structure in emission and absorption. The line emission is mostly due to a large scale ionisation cone energised by the AGN, and a Lya emitting bridge of gas between the radio galaxy and a heavily star-forming set of components. Strangely, the ionisation cone has no Lya emission. We find this is due to an optically thick layer of neutral gas with unity covering fraction spread out over a region of at least ~100 kpc from the AGN. Other less thick absorption components are associated with Lya emitting gas within a few tens of kpc from the radio galaxy and are connected by a bridge of emission. We speculate that this linear structure of dust, Lya and CO emission, and the redshifted absorption seen in the circum nuclear region may represent an accretion flow feeding gas into this massive AGN host galaxy
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