Laser–plasma interactions have been studied in detail over the past twenty years,as they show great potential for the next generation of particle accelerators.The interaction between an ultra-intense laser and a soli...Laser–plasma interactions have been studied in detail over the past twenty years,as they show great potential for the next generation of particle accelerators.The interaction between an ultra-intense laser and a solid-state target produces a huge amount of particles:electrons and photons(X-rays andγ-rays)at early stages of the process,with protons and ions following them.At SPARC LAB Test Facility we have set up two diagnostic lines to perform simultaneous temporally resolved measurements on both electrons and protons.展开更多
This paper presents a new method to control the position of a micro-column snow target. This target enables the measurement of the mean electron density of the pre-plasma created by a pre-pulse with different time del...This paper presents a new method to control the position of a micro-column snow target. This target enables the measurement of the mean electron density of the pre-plasma created by a pre-pulse with different time delays. This research will allow a better understanding of the generation of fast protons from the interaction between a structured pre-plasma and a high intensity laser.展开更多
Enhanced acceleration of protons to high energy by relatively modest high power ultra-short laser pulses, interacting with snow micro-structured targets was recently proposed. A notably increased proton energy was att...Enhanced acceleration of protons to high energy by relatively modest high power ultra-short laser pulses, interacting with snow micro-structured targets was recently proposed. A notably increased proton energy was attributed to a combination of several mechanisms such as localized enhancement of the laser field intensity near the tip of 1 μm size whisker and increase in the hot electron concentration near the tip. Moreover, the use of mass-limited target prevents undesirable spread of absorbed laser energy out of the interaction zone. With increasing laser intensity a Coulomb explosion of the positively charged whisker will occur. All these mechanisms are functions of the local density profile and strongly depend on the laser pre-pulse structure. To clarify the effect of the pre-pulse on the state of the snow micro-structured target at the time of interaction with the main pulse, we measured the optical damage threshold(ODT) of the snow targets. ODT of 0.4 J/cm^2 was measured by irradiating snow micro-structured targets with 50 fs duration pulses of Ti:Sapphire laser.展开更多
文摘Laser–plasma interactions have been studied in detail over the past twenty years,as they show great potential for the next generation of particle accelerators.The interaction between an ultra-intense laser and a solid-state target produces a huge amount of particles:electrons and photons(X-rays andγ-rays)at early stages of the process,with protons and ions following them.At SPARC LAB Test Facility we have set up two diagnostic lines to perform simultaneous temporally resolved measurements on both electrons and protons.
文摘This paper presents a new method to control the position of a micro-column snow target. This target enables the measurement of the mean electron density of the pre-plasma created by a pre-pulse with different time delays. This research will allow a better understanding of the generation of fast protons from the interaction between a structured pre-plasma and a high intensity laser.
文摘Enhanced acceleration of protons to high energy by relatively modest high power ultra-short laser pulses, interacting with snow micro-structured targets was recently proposed. A notably increased proton energy was attributed to a combination of several mechanisms such as localized enhancement of the laser field intensity near the tip of 1 μm size whisker and increase in the hot electron concentration near the tip. Moreover, the use of mass-limited target prevents undesirable spread of absorbed laser energy out of the interaction zone. With increasing laser intensity a Coulomb explosion of the positively charged whisker will occur. All these mechanisms are functions of the local density profile and strongly depend on the laser pre-pulse structure. To clarify the effect of the pre-pulse on the state of the snow micro-structured target at the time of interaction with the main pulse, we measured the optical damage threshold(ODT) of the snow targets. ODT of 0.4 J/cm^2 was measured by irradiating snow micro-structured targets with 50 fs duration pulses of Ti:Sapphire laser.