| 1. |
- Acero, F., et al.
(författare)
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Prospects for Cherenkov Telescope Array Observations of the Young Supernova Remnant RX J1713.7-3946
- 2017
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Ingår i: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 0004-637X .- 1538-4357. ; 840:2
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Tidskriftsartikel (refereegranskat)abstract
- We perform simulations for future Cherenkov Telescope Array (CTA) observations of RX J1713.7-3946, a young supernova remnant (SNR) and one of the brightest sources ever discovered in very high energy (VHE) gamma rays. Special attention is paid to exploring possible spatial (anti) correlations of gamma rays with emission at other wavelengths, in particular X-rays and CO/H I emission. We present a series of simulated images of RX J1713.7-3946 for CTA based on a set of observationally motivated models for the gamma-ray emission. In these models, VHE gamma rays produced by high-energy electrons are assumed to trace the nonthermal X-ray emission observed by XMM-Newton, whereas those originating from relativistic protons delineate the local gas distributions. The local atomic and molecular gas distributions are deduced by the NANTEN team from CO and H I observations. Our primary goal is to show how one can distinguish the emission mechanism(s) of the gamma rays (i.e., hadronic versus leptonic, or a mixture of the two) through information provided by their spatial distribution, spectra, and time variation. This work is the first attempt to quantitatively evaluate the capabilities of CTA to achieve various proposed scientific goals by observing this important cosmic particle accelerator.
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| 2. |
- Delfin, C, et al.
(författare)
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Influence of the medium length on high-order harmonic generation
- 1999
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Ingår i: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 32:22, s. 5397-5409
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Tidskriftsartikel (refereegranskat)abstract
- We study high-order harmonic generation using a 110 fs Ti:sapphire laser loosely focused into a variable-length gas cell filled with neon or argon at 5 mbar pressure. The harmonic intensity is recorded as a function of the medium length, varying between 2 and 21 mm. Several cases are examined, the 17th and the 29th harmonic in argon, and the 29th and 51st harmonic in neon, at the same intensity 4 x 10(14) W cm(-2). We find that the length which maximizes the harmonic yield varies from 10 mm to more than 20 mm. We discuss the different effects affecting the photon yield of the high-order harmonics.
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| 3. |
- Bruno, A, et al.
(författare)
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In situ detection of soot nanoparticles by time-resolved fluorescence analysis
- 2008
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Ingår i: Journal of Optics. A, Pure and Applied Optics. - : IOP Publishing. - 1741-3567 .- 1464-4258. ; 10:6, s. 5-064016
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Tidskriftsartikel (refereegranskat)abstract
- We present a new implementation of the time-resolved fluorescence anisotropy technique for the analysis of carbon nanoparticles directly in a Bunsen-type propane flame. By exploiting femtosecond laser excitation, UV-visible laser-induced fluorescence and time resolution of the experimental set-up, small soot nanoparticles have been identified within the flame. From the measurement of the decay time of the anisotropy ratio, we determined an ensemble-averaged diameter of the carbon particles of approximately 10 nm, with a slightly larger value in the outer edge of the flame compared to its centre.
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