The interaction between a molecular cloud and an external agent(e.g.,a supernova remnant,plasma jet,radiation,or another cloud)is a common phenomenon throughout the Universe and can significantly change the star forma...The interaction between a molecular cloud and an external agent(e.g.,a supernova remnant,plasma jet,radiation,or another cloud)is a common phenomenon throughout the Universe and can significantly change the star formation rate within a galaxy.This process leads to fragmentation of the cloud and to its subsequent compression and can,eventually,initiate the gravitational collapse of a stable molecular cloud.It is,however,difficult to study such systems in detail using conventional techniques(numerical simulations and astronomical observations),since complex interactions of flows occur.In this paper,we experimentally investigate the compression of a foam ball by Taylor–Sedov blast waves,as an analog of supernova remnants interacting with a molecular cloud.The formation of a compression wave is observed in the foam ball,indicating the importance of such experiments for understanding how star formation is triggered by external agents.展开更多
A developing application of laser-driven currents is the generation of magnetic fields of picosecond-nanosecond duration with magnitudes exceeding B=10 T.Single-loop and helical coil targets can direct laser-driven di...A developing application of laser-driven currents is the generation of magnetic fields of picosecond-nanosecond duration with magnitudes exceeding B=10 T.Single-loop and helical coil targets can direct laser-driven discharge currents along wires to generate spatially uniform,quasi-static magnetic fields on the millimetre scale.Here,we present proton deflectometry across two axes of a single-loop coil ranging from 1 to 2 mm in diameter.Comparison with proton tracking simulations shows that measured magnetic fields are the result of kiloampere currents in the coil and electric charges distributed around the coil target.Using this dual-axis platform for proton deflectometry,robust measurements can be made of the evolution of magnetic fields in a capacitor coil target.展开更多
基金the support of Investissements d’Avenir of LabEx PALM(Grant No.ANR-10-LABX-0039-PALM)the Ministry of Science and Higher Education of the Russian Federation(Agreement with Joint Institute for High Temperatures RAS No.075-15-2020-785)G.G.acknowledges support from the UK EPSRC(Grant Nos.EP/M022331/1 and EP/N014472/1)。
文摘The interaction between a molecular cloud and an external agent(e.g.,a supernova remnant,plasma jet,radiation,or another cloud)is a common phenomenon throughout the Universe and can significantly change the star formation rate within a galaxy.This process leads to fragmentation of the cloud and to its subsequent compression and can,eventually,initiate the gravitational collapse of a stable molecular cloud.It is,however,difficult to study such systems in detail using conventional techniques(numerical simulations and astronomical observations),since complex interactions of flows occur.In this paper,we experimentally investigate the compression of a foam ball by Taylor–Sedov blast waves,as an analog of supernova remnants interacting with a molecular cloud.The formation of a compression wave is observed in the foam ball,indicating the importance of such experiments for understanding how star formation is triggered by external agents.
基金This paper was supported by the LLNL Academic Partnership in ICF,EPSRC grants EP/L01663X/1 and EP/L000644/1the Czech Republic MSMT targeted support of Large Infrastructures+1 种基金ELI Beamlines Project LQ1606 of the National Programme of Sustainability IIThe contribution of the JIHT RAS team was completed within the framework of the Russian Ministry state assignment for Science and Higher Education(topic#01201357846).
文摘A developing application of laser-driven currents is the generation of magnetic fields of picosecond-nanosecond duration with magnitudes exceeding B=10 T.Single-loop and helical coil targets can direct laser-driven discharge currents along wires to generate spatially uniform,quasi-static magnetic fields on the millimetre scale.Here,we present proton deflectometry across two axes of a single-loop coil ranging from 1 to 2 mm in diameter.Comparison with proton tracking simulations shows that measured magnetic fields are the result of kiloampere currents in the coil and electric charges distributed around the coil target.Using this dual-axis platform for proton deflectometry,robust measurements can be made of the evolution of magnetic fields in a capacitor coil target.