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Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at Extremes 2024年第4期9卷 16-28页

作者： Weipeng Yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.Chen Emmanuel d’Humières Laurent gremillet Robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle gianluca sarri Yasuhiko Sentoku Hans-Peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien Fuchs LULI-CNRS CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-EMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National Institute for Physics and Nuclear Engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom Department of Physics University of NevadaRenoNevada 89557USA Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan Institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

Demonstration of laser pulse amplification by stimulated Brillouin scattering

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High Power Laser Science and Engineering 2014年第4期 46-51页

作者： E.guillaume K.Humphrey H.Nakamura R.M.g.M.Trines R.Heathcote M.galimberti Y.Amano D.Doria g.Hicks E.Higson S.Kar g.sarri M.Skramic J.Swain K.Tang J.Weston P.Zak E.P.Alves R.A.Fonseca F.Fi ′uza H.Habara K.A.Tanaka R.Bingham M.Borghesi Z.Najmudin L.O.Silva P.A.Norreys Laboratoire d'Optique Appliqu′ee Ecole PolytechniquePalaiseau 91128 France STFC Rutherford Appleton Laboratory Didcot Oxon OX11 0QX United Kingdom University of Strathclyde Glasgow G11XQ United Kingdom Blackett Laboratory Imperial College London Prince Consort RoadLondon SW7 2BZ United Kingdom graduate School of Engineering Osaka University Queens University Belfast Belfast BT7 1NN United Kingdom University of Oxford Parks RoadOxford OX1 3PU United Kingdom

The energy transfer by stimulated Brillouin backscatter from a long pump pulse(15 ps) to a short seed pulse(1 ps)has been investigated in a proof-of-principle demonstration experiment. The two pulses were both amplified in different beamlines of a Nd:glass laser system, had a central wavelength of 1054 nm and a spectral bandwidth of 2 nm, and crossed each other in an underdense plasma in a counter-propagating geometry, off-set by 10?. It is shown that the energy transfer and the wavelength of the generated Brillouin peak depend on the plasma density, the intensity of the laser pulses, and the competition between two-plasmon decay and stimulated Raman scatter instabilities. The highest obtained energy transfer from pump to probe pulse is 2.5%, at a plasma density of 0.17 ncr, and this energy transfer increases significantly with plasma density. Therefore, our results suggest that much higher efficiencies can be obtained when higher densities(above0.25ncr) are used.

关键词： laser–plasma interactions optical pulse generation and compression stimulated Brillouin and Raman scattering ultra-fast optical processes

Pulse chirping effect on controlling the transverse cavity oscillations in nonlinear bubble regime

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Chinese Physics B 2017年第2期26卷 313-319页

作者： H Vosoughian Z Riazi H Afarideh g.sarri Laser and Optic Institute Nuclear Science and Technology Research Institute Tehran Iran physics and Accelerator School Nuclear Science and Technology Research Institute Tehran Iran Department of Energy Engineering and Physics Amirkabir University of Technology P. O. Box 15875-4413 Tehran Iran School of Mathematics and Physics The Queen's University of Belfast BT7 INN Belfast United Kingdom

The propagation of an intense laser pulse in an under-dense plasma induces a plasma wake that is suitable for the acceleration of electrons to relativistic energies. For an ultra-intense laser pulse which has a longitudinal size shorter than the plasma wavelength, λp, instead of a periodic plasma wave, a cavity free from cold plasma electrons, called a bubble, is formed behind the laser pulse. An intense charge separation electric field inside the moving bubble can capture the electrons at the base of the bubble and accelerate them with a narrow energy spread. In the nonlinear bubble regime, due to localized depletion at the front of the pulse during its propagation through the plasma, the phase shift between carrier waves and pulse envelope plays an important role in plasma response. The carrier–envelope phase（CEP） breaks down the symmetric transverse ponderomotive force of the laser pulse that makes the bubble structure unstable. Our studies using a series of two-dimensional（2D） particle-in-cell（PIC） simulations show that the frequency-chirped laser pulses are more effective in controlling the pulse depletion rate and consequently the effect of the CEP in the bubble regime. The results indicate that the utilization of a positively chirped laser pulse leads to an increase in rate of erosion of the leading edge of the pulse that rapidly results in the formation of a steep intensity gradient at the front of the pulse. A more unstable bubble structure, the self-injections in different positions, and high dark current are the results of using a positively chirped laser pulse. For a negatively chirped laser pulse, the pulse depletion process is compensated during the propagation of the pulse in plasma in such a way that results in a more stable bubble shape and therefore, a localized electron bunch is produced during the acceleration process. As a result, by the proper choice of chirping, one can tune the number of self-injected electrons, the size of accelerated bunch

关键词： bubble regime plasma wake field positively chirped laser pulse

An investigation of the L-shell x-ray conversion efficiency for laser-irradiated tin foils

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Plasma Science and Technology 2020年第4期22卷 48-54页

作者： David BAILIE Cormac HYLAND Raj L SINgH Steven WHITE gianluca sarri Francis P KEENAN David RILEY Steven J ROSE Edward g HILL 王菲鹿袁大伟赵刚魏会冈韩波朱宝强朱健强杨朋千 Centre for Plasma Physics School of Mathematics and PhysicsQueen's University BelfastBelfastBT7 INNUnited Kingdom Astrophysics Research Centre School of Mathematics and PhysicsQueen's University BelfastBelfastBT7 INNUnited Kingdom Plasma Physics group Blackett LaboratoryPrince Consort RoadLondonSW72AZUnited Kingdom Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012People's Republic of China Department of Astronomy Beijing Normal UniversityBeijing 100875People's Republic of China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences.Shanghai 201800People's Republic of China

We have used the ShenguangⅡlaser in third harmonic(351 nm)to investigate the emission of L-shell radiation in the 3.3–4.4 ke V range generated using thin foils of Sn coated onto a parylene substrate with irradiation of order 1015 W cm-2 and nanosecond pulse *** our experiment,we have concentrated on assessing the emission on the non-laser irradiated side as this allows an experimental geometry relevant to experiments on photo-ionised plasmas where a secondary target must be placed close to the source,to achieve x-ray fluxes appropriate to astrophysical *** L-shell conversion efficiencies are estimated to be of order 1%,with little dependence on Sn thickness between 400 and 800 nm.

关键词： conversion efficiency laser plasma x-ray sources laboratory astrophysics

Effect of double-balloon enteroscopy on pancreas:An experimental porcine model

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World Journal of gastroenterology 2012年第37期18卷 5181-5187页

作者： Rafael Latorre Federico Soria Octavio López-Albors Ricardo sarriá Francisco Sánchez-Margallo Pilar Esteban Fernando Carballo Enrique Pérez-Cuadrado Department of Anatomy and Comparative Pathology University of MurciaCampus de Espinardo Jesús Usón Minimally Invasive Surgery Center 10071 CáceresSpain Jesús Usón Minimally Invasive Surgery Center Digestive Service Morales Meseguer Hospital Digestive Service Virgen de la Arrixaca Hospital

AIM:To evaluate the effect of double-balloon enteroscopy (DBE) on pancreas histology and levels of pancreatic enzymes. METHODS:Conventional upper gastrointestinal endoscopy was performed on five control pigs. Oral DBE was performed with an EN-450T5 enteroscope on 20 pigs. Two experimental groups (10 pigs each) were defined according to DBE duration:90 min for group 1 and 140 min for group 2. During oral insertion, the balloons were not inflated in the descending part of the duode-num to avoid the minor duodenal papilla. Serum amylase, lipase and C-reactive protein (CRP) levels were monitored before the procedure and repeated every 30 min until the exploration was finished, as well as 24 h and 7 d after. After the procedure and for a total of 7 d, the pigs were observed twice a day for signs of decreased activity, irritability, vomiting or anorexia. gross and microscopic examination of the pancreas was performed on day 7. RESULTS:All animals tolerated DBE without clinical manifestations of acute pancreatitis. Experimental groups had higher levels of enzymes than the control group at 24 h. Throughout the exploration, the amylase levels increased significantly above the baseline 24 h after DBE, although the increase was not statistically significant and did not reach 20% of the baseline. An increase in lipase and CRP was observed at 24 h after the procedure, although by day 7, all enzymatic levels had returned to baseline. No differences between groups 1 and 2 were found for any enzyme and sampling site during and after the procedure. Similarly, no correlation between insertion depth and enzyme levels was observed. Direct in situ and post-removal inspection of the pancreas did not show any evidence of fluid collection, abscesses or hemorrhage. Histological examination of the pancreas from groups 1 and 2 revealed the existence of focal areas (0.14-0.26 mm 2 ) of ischemic necrosis in 47.4% of the animals. In the pigs with damaged pancreas, the left lobe (tail) was always

关键词：急性胰腺炎实验猪双气囊小肠血清淀粉酶显微镜检查组织学检查模型

A Mathematical Model for Deriving Optimal Leasing Policies of a Satellite Operator

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Open Journal of Optimization 2014年第4期3卷 43-58页

作者： Elena sarri george P. Papavassilopoulos School of Electrical and Computer Engineering National Technical University of Athens Athens Greece

This paper presents a dynamic mathematical model of optimal leasing allocation of satellite band-width and services in terms of expected revenues and associated risk. This tool meets the need of a Satellite Operator to determine the optimal leasing policy of the available bandwidth. A methodology and a tool for techno-economic evaluation of satellite services are developed. The output of the tool enables the policy decisions to be customized by the attitude toward risk that the company wants to apply at each time period. The study is based on inputs concerning data and services from an existing Satellite Operator and addresses a real situation. Demand and pricing data have been gathered from the international market. The decision making tool is given in the set-up of a decision tree presenting quantified alternative leasing policies and risks. Sensitivity analysis is also performed to measure the efficiency of the model.

关键词： Decision Making Tool Dynamic Model Satellite Services Techno-Economic Evaluation

Mesenchymal stromal cell delivery as a potential therapeutic strategy against COVID-19:Promising evidence from in vitro results

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World Journal of Biological Chemistry 2022年第2期13卷 47-65页

作者： Panagiotis Mallis Theofanis Chatzistamatiou Zetta Dimou Eirini-Faidra sarri Eleni georgiou Maria Salagianni Vasiliki Triantafyllia Evangelos Andreakos Catherine Stavropoulos-giokas Efstathios Michalopoulos Hellenic Cord Blood Bank Biomedical Research Foundation Academy of AthensAthens 11527Greece Laboratory of Immunobiology Center for ClinicalExperimental Surgery and Translational ResearchBiomedical Research Foundation Academy of AthensAthens 11527Greece

BACKgROUND Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is responsible for the coronavirus disease 2019(COVID-19)pandemic,which was initiated in December ***-19 is characterized by a low mortality rate(ge is higher in elderly people and patients with underlying ***-19 is characterized by mild to severe ***,several therapeutic strategies are evaluated,such as the use of anti-viral drugs,prophylactic treatment,monoclonal antibodies,and *** cellular therapies are also investigated,thus representing an additional therapeutic tool for *** stromal cells(MSCs),which are known for their immunoregulatory properties,may halt the induced cytokine release syndrome mediated by SARS-CoV-2,and can be considered as a potential stem cell *** To evaluate the immunoregulatory properties of MSCs,upon stimulation with COVID-19 patient *** MSCs derived from the human Wharton’s Jelly(WJ)tissue and bone marrow(BM)were isolated,cryopreserved,expanded,and defined according to the criteria outlined by the International Society for Cellular ***,WJ and BM-MSCs were stimulated with a culture medium containing 15%COVID-19 patient serum,1%penicillin-streptomycin,and 1%L-glutamine for 48 *** quantification of interleukin(IL)-1 receptor a(Ra),IL-6,IL-10,IL-13,transforming growth factor(TgF)-β1,vascular endothelial growth factor(VEgF)-a,fibroblast growth factor(FgF),platelet-derived growth factor(PDgF),and indoleamine-2,3-dioxygenase(IDO)was performed using commercial ELISA *** expression of HLA-g1,g5,and g7 was evaluated in unstimulated and stimulated WJ and ***,the interactions between MSCs and patients’macrophages were established using co-culture *** Thawed WJ and BM-MSCs exhibited a spindle-shaped morphology,successfully differentiated to“osteocytes”,“adipocytes”,and“chondrocytes”,and in flow cytometric analysis were characte

关键词： SARS-CoV-2 COVID-19 MSCs Stem cell therapy Cytokine storm Immunomodulation

Quantum electrodynamics experiments with colliding petawatt laser pulses

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High Power Laser Science and Engineering 2019年第1期7卷 74-81页

作者： I. C. E. Turcu B. Shen D. Neely g. sarri K. A. Tanaka P. McKenna S. P. D. Mangles T.-P. Yu W. Luo X.-L. Zhu Y. Yin STFC Rutherford Appleton Laboratory Central Laser Facility School of Electronic Science and Engineering Nanjing University ELI-NP Extreme Light Infrastructure – Nuclear Physics National Institute of Physics and Nuclear Engineering (IFIN HH) State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences School of Physical Science and Technology ShanghaiTech University Shanghai Normal University School of Mathematics and Physics Queen’s University Belfast SUPA Department of Physics University of Strathclyde The John Adams Institute for Accelerator Science Imperial College London Department of Physics National University of Defense Technology School of Nuclear Science and Technology University of South China Key Laboratory for Laser Plasmas (MOE) School of Physics and Astronomy Shanghai Jiao Tong University

A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt(PW)and even 100 PW, capable of reaching intensities of 1023 W/cm^2 in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity IS= 2.3×1029 W/cm^2 at which the theory of quantum electrodynamics(QED) predicts that a large part of the energy of the laser photons will be transformed to hard gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of 10 PW focused to intensities 10^(22) W/cm^2.

关键词： colliding petawatt laser pulses electron-positron pairs creation nonlinear Breit-Wheeler process petawatt laser facilities quantum electrodynamics

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青少年犯罪行为与发育成熟(英文)

教育生物学杂志 2013年第4期1卷 259-262页

作者： Rosemary C.sarri 密西根大学社会学研究所

青少年罪犯是否需要以成人身份为其犯罪行为接受检控及监禁一直备受争议。在本文中,作者的答案是否定的。其以近期神经认知科学的发现为论据,指出青少年的前额皮层仍在发育中,故不应因其行为而受到太大惩罚。前额皮层的不成熟在青少年... 详细信息

青少年罪犯是否需要以成人身份为其犯罪行为接受检控及监禁一直备受争议。在本文中,作者的答案是否定的。其以近期神经认知科学的发现为论据,指出青少年的前额皮层仍在发育中,故不应因其行为而受到太大惩罚。前额皮层的不成熟在青少年罪犯中尤为明显,因为其有更大的机会受到虐待及遭到创伤,导致前额皮层受损。作者促请现行法律制度在检控青少年犯罪时需考虑其在神经认知方面发育未全。

关键词：青少年犯罪行为大脑发育