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The next generation of instrumentation for nuclear astrophysics will have to achieve a factor of 10-100 improvement in sensitivity over present technologies. With the focusing gamma-ray telescope MAX we take up this challenge: combining unprecedented sensitivity with high spectral and angular resolution, and the capability of measuring the polarization of the incident photons. The feasibility of such a crystal diffraction gamma-ray lens has recently been demonstrated with the prototype lens CLAIRE. MAX is a proposed mission which will make use of satellite formation flight to achieve 86m focal length, with the Laue lens being carried by one satellite and the detector by the other. In the current design, the Laue diffraction lens of MAX will consist of 13740 copper and germanium (Ge1−x Six, x ∼ 0.02) crystal tiles arranged on 36 concentric rings. It simultaneously focuses in two energy bands, each centred on one of the main scientific objectives of the mission: the 800-900 keV band is dedicated to the study of nuclear gamma-ray lines from type Ia supernovae (e.g. 56Co decay line at 847 keV) while the 450-530 keV band focuses on electron-positron annihilation (511 keV emission) from the Galactic centre region with the aim of resolving potential point sources. MAX promises a breakthrough in the study of point sources at gamma-ray energies by combining high narrow-line sensitivity (better than 10−6 cm−2 s−1) and high energy resolution (E/dE ∼ 500). The mission has successfully undergone a pre-phase A study with the French Space Agency CNES, and continues to evolve: new diffracting materials such as bent or composite crystals seem very promising. [ABSTRACT FROM AUTHOR]

We discuss how several of the questions that remain unclear on the physics of Active Galactic Nuclei may find elements of answers when using in the coming years the extraordinary set of instruments that will be flying simultaneously to observe in all bands of the electromagnetic spectrum. The choice of questions mentioned here is personal and not exhaustive. [ABSTRACT FROM AUTHOR]

The filamentation of powerful, ultrashort laser pulses in liquids is investigated, both experimentally and numerically, varying two-photon absorption dye concentration. Pump-dump pulse experiments furthermore locks in phase each filament fluorescence leading to bright interference patterns. [ABSTRACT FROM AUTHOR]

We explore the possibility that the Kα line from the thermal matter may appear at tens of keV due to a high Doppler blue-shift. In the jet comoving frame, the energy density of photons originally emitted by the accretion disk and reflected off the broad line region clouds dominates over that of photons of other origin. We discuss the photoionization states of the thermal matter and find that the irons elements are neutral. The high metallicity in quasars enhances the possibility to detect the thermal matter in the relativistic jet in some radio-loud quasars. A highly Doppler blue-shifted Kα line may be detected. We make a prediction for 3C 273, in which the Kα line luminosity might be of the order 3.0× 1044erg s-1 with an equivalent width of 2.4 keV. Such a line could be detected in a future mission. [ABSTRACT FROM AUTHOR]