The use of ultra-high intensity laser beams to achieve extreme material states in the laboratory has become almost routine with the development of the petawatt laser. Petawatt class lasers have been constructed for sp...The use of ultra-high intensity laser beams to achieve extreme material states in the laboratory has become almost routine with the development of the petawatt laser. Petawatt class lasers have been constructed for specific research activities,including particle acceleration, inertial confinement fusion and radiation therapy, and for secondary source generation(x-rays, electrons, protons, neutrons and ions). They are also now routinely coupled, and synchronized, to other large scale facilities including megajoule scale lasers, ion and electron accelerators, x-ray sources and z-pinches. The authors of this paper have tried to compile a comprehensive overview of the current status of petawatt class lasers worldwide.The definition of ‘petawatt class' in this context is a laser that delivers >200 TW.展开更多
There are several petawatt-scale laser facilities around the world and the fidelity of the pulses to target is critical in achieving the highest focused intensities and the highest possible contrast. The United Kingdo...There are several petawatt-scale laser facilities around the world and the fidelity of the pulses to target is critical in achieving the highest focused intensities and the highest possible contrast. The United Kingdom has three such laser facilities which are currently open for access to the academic community: Orion at AWE, Aldermaston and Vulcan & Astra-Gemini at the Central Laser Facility(CLF), STFC(Science and Technology Facilities Council)Rutherford Appleton Laboratory(RAL). These facilities represent the two main classes of petawatt facilities: the mixed OPCPA/Nd:glass high-energy systems of Orion and Vulcan and the ultra-short-pulse Ti:Sapphire system of AstraGemini. Many of the techniques used to enhance and control the pulse generation and delivery to target have been pioneered on these facilities. In this paper, we present the system designs which make this possible and discuss the contrast enhancement schemes that have been implemented.展开更多
The Atomic Weapons Establishment(AWE) is tasked with supporting Continuous At Sea Deterrence(CASD) by certifying the performance and safety of the national deterrent in the Comprehensive Test Ban Treaty(CTBT) era. Thi...The Atomic Weapons Establishment(AWE) is tasked with supporting Continuous At Sea Deterrence(CASD) by certifying the performance and safety of the national deterrent in the Comprehensive Test Ban Treaty(CTBT) era. This means that recourse to further underground testing is not possible, and certification must be achieved by supplementing the historical data with the use of computer calculation. In order to facilitate this, AWE operates some of the largest supercomputers in the UK. To validate the computer codes, and indeed the designers who are using them, it is necessary to carry out further experiments in the right regimes. An excellent way to meet many of the requirements for material property data and to provide confidence in the validity of the algorithms is through experiments carried out on high power laser facilities.展开更多
In 2018 the journal High Power Laser Science and Engineering produced a Special Issue on Laboratory Astrophysics.The scope of the special issue was to span the latest research and reviews on the following topics relat...In 2018 the journal High Power Laser Science and Engineering produced a Special Issue on Laboratory Astrophysics.The scope of the special issue was to span the latest research and reviews on the following topics related to laboratory astrophysics and related phenomena.The topics invited for inclusion were:·collisionless shocks;·planetary formation dynamics and planetary interiors;·warm dense matter;·hydrodynamic and magnetohydrodynamic instabilities;·magnetic reconnection;·relativistic plasmas;·magnetic turbulence and magnetic amplification;·nuclear astrophysics;·radiative transfer and radiation hydrodynamics;·target design;·laser-based HED facilities.although this was not meant as an exhaustive list.As is usual with a special issue of this type vip Editors were invited to lead in sourcing articles.展开更多
David Neely was an internationally recognised scientist who formed collaborations and friendships across the world. His passion for his work always shone through. He always made time for early-career scientists and be...David Neely was an internationally recognised scientist who formed collaborations and friendships across the world. His passion for his work always shone through. He always made time for early-career scientists and became a mentor and supervisor to many. He was an active Editorial Board Member of the international journal High Power Laser Science and Engineering. Sadly, David was taken from us much too early. In this Editorial we pay tribute to his work through his publications in the journal.展开更多
In 2017 the journal High Power Laser Science and Engineering produced a Special Issue on Target Fabrication.The scope of the special issue was to span the latest developments and reviews on topics related to their dep...In 2017 the journal High Power Laser Science and Engineering produced a Special Issue on Target Fabrication.The scope of the special issue was to span the latest developments and reviews on topics related to their deployment on ultrahigh-energy/power laser facilities.The topics invited for inclusion were:·Target assembly·Novel characterization展开更多
The Orion facility at the Atomic Weapons Establishment in the United Kingdom has the capability to operate one of its two 500 J, 500 fs short-pulse petawatt beams at the second harmonic, the principal reason being to ...The Orion facility at the Atomic Weapons Establishment in the United Kingdom has the capability to operate one of its two 500 J, 500 fs short-pulse petawatt beams at the second harmonic, the principal reason being to increase the temporal contrast of the pulse on target. This is achieved post-compression, using 3 mrn thick type-1 potassium dihydrogen phosphate crystals. Since the beam diameter of the compressed pulse is ~600 mm, it is impractical to achieve this over the full aperture due to the unavailability of the large aperture crystals. Frequency doubling was originally achieved on Orion using a circular sub-aperture of 300 mm diameter. The reduction in aperture limited the output energy to 100 J. The second-harmonic capability has been upgraded by taking two square 300 mmx 300 mm sub-apertures from the beam and combining them at focus using a single paraboloidal mirror, thus creating a 200 J, 500 fs, i.e., 400 TW facility at the second harmonic.展开更多
文摘The use of ultra-high intensity laser beams to achieve extreme material states in the laboratory has become almost routine with the development of the petawatt laser. Petawatt class lasers have been constructed for specific research activities,including particle acceleration, inertial confinement fusion and radiation therapy, and for secondary source generation(x-rays, electrons, protons, neutrons and ions). They are also now routinely coupled, and synchronized, to other large scale facilities including megajoule scale lasers, ion and electron accelerators, x-ray sources and z-pinches. The authors of this paper have tried to compile a comprehensive overview of the current status of petawatt class lasers worldwide.The definition of ‘petawatt class' in this context is a laser that delivers >200 TW.
文摘There are several petawatt-scale laser facilities around the world and the fidelity of the pulses to target is critical in achieving the highest focused intensities and the highest possible contrast. The United Kingdom has three such laser facilities which are currently open for access to the academic community: Orion at AWE, Aldermaston and Vulcan & Astra-Gemini at the Central Laser Facility(CLF), STFC(Science and Technology Facilities Council)Rutherford Appleton Laboratory(RAL). These facilities represent the two main classes of petawatt facilities: the mixed OPCPA/Nd:glass high-energy systems of Orion and Vulcan and the ultra-short-pulse Ti:Sapphire system of AstraGemini. Many of the techniques used to enhance and control the pulse generation and delivery to target have been pioneered on these facilities. In this paper, we present the system designs which make this possible and discuss the contrast enhancement schemes that have been implemented.
文摘The Atomic Weapons Establishment(AWE) is tasked with supporting Continuous At Sea Deterrence(CASD) by certifying the performance and safety of the national deterrent in the Comprehensive Test Ban Treaty(CTBT) era. This means that recourse to further underground testing is not possible, and certification must be achieved by supplementing the historical data with the use of computer calculation. In order to facilitate this, AWE operates some of the largest supercomputers in the UK. To validate the computer codes, and indeed the designers who are using them, it is necessary to carry out further experiments in the right regimes. An excellent way to meet many of the requirements for material property data and to provide confidence in the validity of the algorithms is through experiments carried out on high power laser facilities.
文摘In 2018 the journal High Power Laser Science and Engineering produced a Special Issue on Laboratory Astrophysics.The scope of the special issue was to span the latest research and reviews on the following topics related to laboratory astrophysics and related phenomena.The topics invited for inclusion were:·collisionless shocks;·planetary formation dynamics and planetary interiors;·warm dense matter;·hydrodynamic and magnetohydrodynamic instabilities;·magnetic reconnection;·relativistic plasmas;·magnetic turbulence and magnetic amplification;·nuclear astrophysics;·radiative transfer and radiation hydrodynamics;·target design;·laser-based HED facilities.although this was not meant as an exhaustive list.As is usual with a special issue of this type vip Editors were invited to lead in sourcing articles.
文摘David Neely was an internationally recognised scientist who formed collaborations and friendships across the world. His passion for his work always shone through. He always made time for early-career scientists and became a mentor and supervisor to many. He was an active Editorial Board Member of the international journal High Power Laser Science and Engineering. Sadly, David was taken from us much too early. In this Editorial we pay tribute to his work through his publications in the journal.
文摘In 2017 the journal High Power Laser Science and Engineering produced a Special Issue on Target Fabrication.The scope of the special issue was to span the latest developments and reviews on topics related to their deployment on ultrahigh-energy/power laser facilities.The topics invited for inclusion were:·Target assembly·Novel characterization
文摘The Orion facility at the Atomic Weapons Establishment in the United Kingdom has the capability to operate one of its two 500 J, 500 fs short-pulse petawatt beams at the second harmonic, the principal reason being to increase the temporal contrast of the pulse on target. This is achieved post-compression, using 3 mrn thick type-1 potassium dihydrogen phosphate crystals. Since the beam diameter of the compressed pulse is ~600 mm, it is impractical to achieve this over the full aperture due to the unavailability of the large aperture crystals. Frequency doubling was originally achieved on Orion using a circular sub-aperture of 300 mm diameter. The reduction in aperture limited the output energy to 100 J. The second-harmonic capability has been upgraded by taking two square 300 mmx 300 mm sub-apertures from the beam and combining them at focus using a single paraboloidal mirror, thus creating a 200 J, 500 fs, i.e., 400 TW facility at the second harmonic.
