Enhancement of Target Normal Sheath Acceleration via Improved Fast Electron Heating in a Controlled Pre-Plasma Driven by a Femtosecond Laser Pre-Pulse

Enhancement of Target Normal Sheath Acceleration via Improved Fast Electron Heating in a Controlled Pre-Plasma Driven by a Femtosecond Laser Pre-Pulse | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Enhancement of Target Normal Sheath Acceleration via Improved Fast Electron Heating in a Controlled Pre-Plasma Driven by a Femtosecond Laser Pre-Pulse Leonida Gizzi, Elisabetta Boella, Luca Labate, Federica Baffigi, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-365870/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract The interaction of ultraintense laser pulses with solids is largely affected by the plasma gradient at the vacuum-solid interface, which modifies the absorption and ultimately, controls the energy distribution function of heated electrons. A micrometer scale-length plasma has been predicted to yield a significant enhancement of the energy and weight of the fast electron population and to play a major role in laser-driven proton acceleration with thin foils. We report on recent experimental results on proton acceleration from laser interaction with foil targets at ultra-relativistic intensities. We show a three-fold increase of the proton cut-off energy when a micrometer scale-length pre-plasma is introduced by irradiation with a low energy femtosecond pre-pulse. Our realistic numerical simulations agree with the observed gain of the proton cut-off energy and confirm the role of stochastic heating of fast electrons in the enhancement of the accelerating sheath field. Plasma and Fluids Atomic and Molecular Physics Enhancement Acceleration electron heating pre-plasma Figures Figure 1 Figure 2 Figure 3 Figure 4 Full Text Due to technical limitations, full-text HTML conversion of this manuscript could not be completed. However, the manuscript can be downloaded and accessed as a PDF. Additional Declarations No competing interests reported. Supplementary Files GizzietalSupplMaterial.pdf Cite Share Download PDF Status: Under Review Version 1 posted Editor assigned by journal 14 Apr, 2021 Editor invited by journal 14 Apr, 2021 Submission checks completed at journal 14 Apr, 2021 First submitted to journal 26 Mar, 2021 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-365870","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":21245244,"identity":"f27dbf09-0a0c-47d9-a1bb-f4e9d4ea0a01","order_by":0,"name":"Leonida 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Milano","correspondingAuthor":false,"prefix":"","firstName":"Alberto","middleName":"","lastName":"Fazzi","suffix":""},{"id":21245255,"identity":"f95769af-dafd-48fb-a5e7-60ef506d717c","order_by":8,"name":"Lorenzo Fulgentini","email":"","orcid":"","institution":"Intense Laser Irradiation Laboratory, INO-CNR, Pisa","correspondingAuthor":false,"prefix":"","firstName":"Lorenzo","middleName":"","lastName":"Fulgentini","suffix":""},{"id":21245256,"identity":"c8cf4fe9-cc6a-494e-89fe-8405fb029d17","order_by":9,"name":"Dario Giove","email":"","orcid":"","institution":"INFN-LASA, Segrate","correspondingAuthor":false,"prefix":"","firstName":"Dario","middleName":"","lastName":"Giove","suffix":""},{"id":21245257,"identity":"af94df6e-bfef-46aa-bddd-2d8a077c7921","order_by":10,"name":"Petra Koester","email":"","orcid":"","institution":"Intense Laser Irradiation Laboratory, INO-CNR, Pisa","correspondingAuthor":false,"prefix":"","firstName":"Petra","middleName":"","lastName":"Koester","suffix":""},{"id":21245258,"identity":"db20f13f-6d83-4fba-ae55-91942ade4cd0","order_by":11,"name":"Daniele Palla","email":"","orcid":"","institution":"Intense Laser Irradiation Laboratory, INO-CNR, Pisa","correspondingAuthor":false,"prefix":"","firstName":"Daniele","middleName":"","lastName":"Palla","suffix":""},{"id":21245259,"identity":"67a01a33-c4a8-4104-90bb-d400afd795b2","order_by":12,"name":"Paolo Tomassini","email":"","orcid":"","institution":"Intense Laser Irradiation Laboratory, INO-CNR, Pisa","correspondingAuthor":false,"prefix":"","firstName":"Paolo","middleName":"","lastName":"Tomassini","suffix":""}],"badges":[],"createdAt":"2021-03-26 13:29:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-365870/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-365870/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":8061774,"identity":"22308435-a0bb-4e1f-aafa-3f65f551b6fa","added_by":"auto","created_at":"2021-04-15 20:46:48","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":82531,"visible":true,"origin":"","legend":"(left) Comparison of experimental proton spectra obtained from the TPS for 10 µm thick Al targets without pre-plasma and 25 µm thick Ti target with the pre-plasma. Sample error bars on the measured proton energy are shown for two spectra and are indicative of the error-bars for all the curves. (right) Comparison of experimental spectra obtained from deconvolution of the temporal evolution of the TOF signals from a set of Titanium foil targets of different thickness of 2, 5, 12.5 and 25 µm. All data were taken without the pre-plasma, except the purple line for 25 µm with cut-off energy at 10 MeV. Sample error bars on the measured proton energy are shown on the two spectra with 25 µm Ti targets.","description":"","filename":"fig1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1/32285424c4b737603ec276c3.jpg"},{"id":8061777,"identity":"7be228f6-c3a2-4bc2-9600-733d41f3af47","added_by":"auto","created_at":"2021-04-15 20:46:49","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":47385,"visible":true,"origin":"","legend":"3D PIC simulation results: (a) Proton energy spectra for a 10 µm Al target for different pre-plasma scalength: Lg = 0:13 (blue), 0:42 (red) and 1:27 µm (green). The black curve corresponds to a sharp plasma-vacuum transition. (b) Cut-off energy vs pre-plasma scalength for the cases in (a).","description":"","filename":"fig2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1/c83888389b0c9d6178cae46b.jpg"},{"id":8061773,"identity":"7cbe8e18-b25c-4e62-ab9e-ef217c7b1551","added_by":"auto","created_at":"2021-04-15 20:46:48","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":133551,"visible":true,"origin":"","legend":"2D PIC simulations: (a, b) Laser electric field and longitudinal density profile (black solid line), (c, d) electron density, (e, f) longitudinal electric field and (g, h) electron kinetic energy density at t = 0:11 ps for a Ti plasma with Lg = 5 (left column) and 0:13 µm (right column). The black dashed lines in (a, b) denote the position of the critical density and the relativistic critical density. The inset in (c) is an enlargement showing details of the electron cavities on the target surface. The black solid lines in (e, f) represent the electric field lineout in the middle of the simulation box.","description":"","filename":"fig3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1/e49d744200ee0ea05d7d3cd5.jpg"},{"id":8061776,"identity":"1749eda4-5c5d-45e9-bfcb-7b431e880055","added_by":"auto","created_at":"2021-04-15 20:46:49","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":53808,"visible":true,"origin":"","legend":"2D PIC simulations results: (a) Electron distribution for density scale-length Lg = 0:13 (orange), 0:25 (blue), 1:27 (green), 3:38 (red) and 5:07 mm (black). (b) Proton cut-off energy vs pre-plasma scale length and (c) proton angular distribution for the cases in (a).","description":"","filename":"fig4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1/65b195aafec5b32fba37c92a.jpg"},{"id":13622193,"identity":"8637689c-0247-49b0-ba22-db9f7c440b6e","added_by":"auto","created_at":"2021-09-17 07:13:45","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1435644,"visible":true,"origin":"","legend":"","description":"","filename":"Gizzietalmanuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1_covered.pdf"},{"id":8062345,"identity":"f3db6f86-134d-4fd6-9d16-7a7a5ed73f62","added_by":"auto","created_at":"2021-04-15 20:49:54","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1497044,"visible":true,"origin":"","legend":"","description":"","filename":"Gizzietalmanuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1_stamped.pdf"},{"id":8061775,"identity":"48c66037-85f0-4b66-b07c-f3512c1eace2","added_by":"auto","created_at":"2021-04-15 20:46:48","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":711679,"visible":true,"origin":"","legend":"","description":"","filename":"GizzietalSupplMaterial.pdf","url":"https://assets-eu.researchsquare.com/files/rs-365870/v1/409213d871d206847696e2cd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eEnhancement of Target Normal Sheath Acceleration via Improved Fast Electron Heating in a Controlled Pre-Plasma Driven by a Femtosecond Laser Pre-Pulse\u003c/p\u003e","fulltext":[{"header":"Full Text","content":"\u003cp\u003eDue to technical limitations, full-text HTML conversion of this manuscript could not be completed. 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A micrometer scale-length plasma has been predicted to yield a significant enhancement of the energy and weight of the fast electron population and to play a major role in laser-driven proton acceleration with thin foils. We report on recent experimental results on proton acceleration from laser interaction with foil targets at ultra-relativistic intensities. We show a three-fold increase of the proton cut-off energy when a micrometer scale-length pre-plasma is introduced by irradiation with a low energy femtosecond pre-pulse. Our realistic numerical simulations agree with the observed gain of the proton cut-off energy and confirm the role of stochastic heating of fast electrons in the enhancement of the accelerating sheath field.","manuscriptTitle":"Enhancement of Target Normal Sheath Acceleration via Improved Fast Electron Heating in a Controlled Pre-Plasma Driven by a Femtosecond Laser Pre-Pulse","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2021-04-15 20:46:47","doi":"10.21203/rs.3.rs-365870/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorAssigned","content":"","date":"2021-04-14T15:37:40+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2021-04-14T15:14:04+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2021-04-14T04:58:33+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2021-03-26T13:17:25+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1a22fc48-3c1a-4998-b436-fd67097c3390","owner":[],"postedDate":"April 15th, 2021","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":3654804,"name":"Plasma and Fluids"},{"id":3654805,"name":"Atomic and Molecular Physics"}],"tags":[],"updatedAt":"2021-05-10T07:29:12+00:00","versionOfRecord":[],"versionCreatedAt":"2021-04-15 20:46:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-365870","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-365870","identity":"rs-365870","version":["v1"]},"buildId":"_2-kVJe1T_tPrBINL-cwx","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}