304L 6.35 * 1mm Intsimbi engenastainless ebhijelwe ababoneleli ngeetyhubhu, Umboniso womqadi we-lithium oqinileyo wokuvelisa iineutron ezithe ngqo

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Njengenye indlela kuphononongo lwezixhobo zenyukliya, ijenereyitha ye-neutron eqhutywa yi-compact eqhutywa yi-accelerator esebenzisa i-lithium-ion beam driver inokuba ngumgqatswa othembisayo kuba ivelisa imitha engafunekiyo encinci.Nangona kunjalo, kwakunzima ukuhambisa umqadi oqinileyo we-lithium ion, kwaye ukusetyenziswa kwezixhobo ezinjalo kwakubhekwa njengento engenakwenzeka.Eyona ngxaki inzima kakhulu yokungonelanga kwe-ion flow yasonjululwa ngokusetyenziswa kweskimu sokumiliselwa kweplasma ngokuthe ngqo.Kulo cwangciso, i-plasma ye-pulsed high-density eveliswa yi-laser ablation ye-lithium metal foil ifakwe ngokufanelekileyo kwaye iqhutywe yi-high-frequency quadrupole accelerator (RFQ accelerator).Siye safumana i-peak beam current ye-35 mA ikhawuleze ukuya kwi-1.43 MeV, eyimiyalelo emibini yobukhulu obuphezulu kune-injector eqhelekileyo kunye neenkqubo ze-accelerator ezinokubonelela.
Ngokungafaniyo ne-X-reyi okanye amasuntswana ahlawuliweyo, i-neutron inobunzulu bokungena obukhulu kunye nokunxibelelana okukodwa kunye nombandela ojikiweyo, ubenze babe probes eziguquguqukayo kakhulu zokufunda iipropati zezinto1,2,3,4,5,6,7.Ngokukodwa, iindlela zokusasaza i-neutron ziqhele ukusetyenziselwa ukufunda ukubunjwa, ukwakheka, kunye noxinzelelo lwangaphakathi kwimiba ephonsiweyo kwaye inokubonelela ngolwazi oluthe kratya malunga neekhompawundi zomkhondo kwiialloyi zetsimbi ekunzima ukuzibona kusetyenziswa i-X-ray spectroscopy8.Le ndlela ithathwa njengesixhobo esinamandla kwisayensi esisiseko kwaye isetyenziswa ngabavelisi besinyithi kunye nezinye izinto.Kutshanje, i-neutron diffraction isetyenziselwe ukufumanisa uxinzelelo olushiyekileyo kumatshini onjengololiwe kunye neenxalenye zenqwelomoya9,10,11,12.Neutrons zikwasetyenziswa kwioyile kunye nerhasi amaqula kuba ngokulula abanjwe ngezinto proton-rich13.Iindlela ezifanayo zikwasetyenziswa kubunjineli boluntu.Uvavanyo lwe-neutron olungonakalisi sisixhobo esisebenzayo sokubona iimpazamo ezifihliweyo kwizakhiwo, iitonela kunye neebhulorho.Ukusetyenziswa imiqadi neutron ngokukhutheleyo isetyenziswa kuphando lwezenzululwazi kunye noshishino, uninzi lwazo ngokwembali zaphuhliswa usebenzisa reactors yenyukliya.
Nangona kunjalo, kunye nemvumelwano yehlabathi malunga nokwanda kwenyukliya, ukwakha izixhobo ezincinci zereactor ngeenjongo zophando kuya kuba nzima.Ngaphezu koko, ingozi yakutshanje yaseFukushima yenze ukuba isakhiwo sezixhobo zenyukliya samkeleke eluntwini.Ngokunxulumene nalo mkhwa, imfuno yemithombo ye-neutron kwi-accelerators iyakhula2.Njengenye indlela yezixhobo zenyukliya, imithombo emininzi ye-accelerator-splitting neutron sele iyasebenza14,15.Nangona kunjalo, ukusetyenziswa ngokufanelekileyo kweempawu zemiqadi ye-neutron, kuyimfuneko ukwandisa ukusetyenziswa kwemithombo ye-compact kwi-accelerators, i-16 enokuthi ibe yamaziko ophando oshishino kunye neyunivesithi.Imithombo ye-Accelerator neutron yongeze amandla amatsha kunye nemisebenzi ukongeza ekusebenzeni njengokutshintsha kwezixhobo zenyukliya14.Umzekelo, i-linac-driven generator inokwenza lula umlambo we-neutron ngokulawula umqadi wokuqhuba.Nje ukuba zikhutshiwe, iineutron kunzima ukulawula kwaye imilinganiselo yemitha kunzima ukuyihlalutya ngenxa yengxolo edalwe yi-neutron yangasemva.Neutron pulsed elawulwa i accelerator ukuphepha le ngxaki.Iiprojekthi ezininzi ezisekwe kwitekhnoloji yokukhawulezisa iproton ziye zacetywa kwihlabathi liphela17,18,19.Iireactions 7Li(p, n)7Be and 9Be(p, n)9B zezona zisetyenziswa rhoqo kwiproton-driven compact neutron generators because they are endothermic reactions20.Ukugqithiswa kwemitha yemitha kunye nenkunkuma ye-radioactive inokuncitshiswa ukuba amandla akhethwe ukuvuyisa umqa weproton angaphezulu kancinane kwixabiso lomqobo.Nangona kunjalo, ubunzima be-nucleus ekujoliswe kuyo bukhulu kakhulu kunobo beeprotons, kwaye i-neutrons ephumela kuyo isasazeke kuwo onke amacala.Oku kufutshane nokukhutshwa kwe-isotropic ye-neutron flux kuthintela ukuthuthwa okusebenzayo kwee-neutron ukuya kwinto yokufunda.Ukongeza, ukufumana idosi efunekayo ye-neutron kwindawo yento, kuyimfuneko ukwandisa ngokubonakalayo zombini inani leeproton ezihambayo kunye namandla azo.Ngenxa yoko, iidosi ezinkulu zemitha ye-gamma kunye ne-neutron ziya kusasazeka ngee-engile ezinkulu, zitshabalalisa i-advanteji ye-endothermic reactions.Ijenereyitha ye-neutron esekwe kwiproton ene-accelerator inamandla okukhusela kwimitha kwaye yeyona nxalenye inkulu yenkqubo.Isidingo sokunyusa amandla okuqhuba iiprotons sidla ngokufuna ukongezwa okongeziweyo kubungakanani bendawo ye-accelerator.
Ukoyisa iintsilelo ngokubanzi zemithombo ye-neutron ecwengileyo kwi-accelerators, iskim se-inversion-kinematic reaction yacetywa21.Kulo cwangciso, i-lithium-ion beam enzima isetyenziswe njengesikhokelo sesikhokelo endaweni yeproton, ejolise kwizinto ezicebileyo ze-hydrogen ezifana neeplastiki ze-hydrocarbon, i-hydrides, i-hydrogen gas, okanye i-hydrogen plasma.Ezinye iindlela ziye zaqwalaselwa, ezifana ne-beryllium ion-driven beams, nangona kunjalo, i-beryllium yinto enetyhefu efuna ukunakekelwa okukhethekileyo ekuphatheni.Ngoko ke, i-lithium beam yeyona nto ifanelekileyo kwi-inversion-kinematic reaction schemes.Ekubeni isantya se-lithium nuclei inkulu kuneeprotons, iziko lobunzima bongquzulwano lwenyukliya lihlala liqhubela phambili, kwaye i-neutron nayo ikhutshwa phambili.Olu phawu luyiphelisa kakhulu imitha ye-gamma engafunekiyo kunye nokukhutshwa kwe-neutron ephezulu22.Ukuthelekiswa kwemeko eqhelekileyo ye-injini yeproton kunye ne-inverse kinematics scenario iboniswe kwi-Figure 1.
Umzobo wee-angles ze-neutron zokuvelisa iproton kunye ne-lithium (ezotywe nge-Adobe Illustrator CS5, 15.1.0, https://www.adobe.com/products/illustrator.html).(a) I-Neutron inokukhutshwa kulo naliphi na icala ngenxa yokusabela ngenxa yokuba iiprotoni ezihambayo zibethe ii-athomu ezinzima kakhulu kwithagethi ye-lithium.(b) Ngokuchaseneyo, ukuba umqhubi we-lithium-ion ubhobhoza i-target ye-hydrogen-rich, i-neutron iveliswa kwikhowuni emxinwa kwindlela eya phambili ngenxa yesantya esiphezulu seziko lobunzima benkqubo.
Nangona kunjalo, zimbalwa kuphela iijenereyitha ze-neutron zekinematic eziguqukileyo ezikhoyo ngenxa yobunzima bokuvelisa i-flux efunekayo yeeyoni ezinzima kunye nentlawulo ephezulu xa kuthelekiswa neeproton.Zonke ezi zityalo zisebenzisa imithombo ye-ion ye-sputter engalunganga ngokudibanisa ne-tandem electrostatic accelerators.Ezinye iintlobo zemithombo ye-ion ziye zacetywa ukwandisa ukusebenza kwe-beam acceleration26.Kuyo nayiphi na imeko, i-lithium-ion beam ekhoyo yangoku ikhawulelwe kwi-100 µA.Kucetywayo ukusebenzisa i-1 mA ye-Li3 + 27, kodwa le ntsimbi ye-ion yangoku ayizange iqinisekiswe ngale ndlela.Ngokumalunga nokuqina, i-lithium beam accelerators ayikwazi ukukhuphisana ne-proton beam accelerators apho i-peak proton yangoku idlula i-10 mA28.
Ukuphumeza i-generator compact neutron generator esekelwe kwi-lithium-ion beam, kunenzuzo ukuvelisa ubuninzi obuphezulu obungenayo i-ion.Iiyoni zikhawuleza kwaye zikhokelwa ngamandla ombane, kwaye inqanaba lentlawulo ephezulu likhokelela kwisantya esisebenzayo.Abaqhubi be-Li-ion beam bafuna i-Li3 + i-peak currents engaphezulu kwe-10 mA.
Kulo msebenzi, sibonisa ukukhawuleziswa kweentsimbi ze-Li3 + kunye nesantya esiphezulu ukuya kwi-35 mA, enokuthelekiswa ne-proton accelerators ephezulu.I-original lithium ion beam yenziwa kusetyenziswa i-laser ablation kunye ne-Direct Plasma Implantation Scheme (DPIS) eyaphuhliswa ekuqaleni ukukhawulezisa i-C6 +.Irediyo eyilwe ngokwezifiso i-quadrupole linac (RFQ linac) yenziwe kusetyenziswa ulwakhiwo oluneentonga ezine.Siye saqinisekisa ukuba umqadi okhawulezayo unawo amandla okubalwayo aphezulu ococeko oluphezulu.Emva kokuba i-beam ye-Li3 + ibanjwe ngokufanelekileyo kwaye ikhutshwe yi-accelerator ye-radio frequency (RF), icandelo elilandelayo le-linac (i-accelerator) lisetyenziselwa ukubonelela amandla afunekayo ukuvelisa i-neutron flux eqinile kwithagethi.
Ukukhawuleziswa kweeyoni zokusebenza okuphezulu kubuchwephesha obusekwe kakuhle.Umsebenzi oseleyo wokuqonda ijenereyitha entsha ye-neutron esebenza ngokugqibeleleyo kukuvelisa inani elikhulu leeyoni ze-lithium ezihluthwe ngokupheleleyo kwaye zenze ulwakhiwo lweqela elibandakanya uthotho lwee-ion pulses ezidityaniswa nomjikelo weRF kwi-accelerator.Iziphumo zovavanyo ezenzelwe ukufezekisa le njongo zichazwe kula macandelwana mathathu alandelayo: (1) isizukulwana se-lithium-ion beam ngokupheleleyo, (2) i-acceleration ye-beam usebenzisa i-RFQ linac eyenzelwe ngokukodwa, kunye (3) nokukhawuleza ukuhlalutya. yomqadi ukujonga imixholo yayo.Kwi-Brookhaven National Laboratory (BNL), sakha ukusetwa kovavanyo oluboniswe kuMfanekiso 2.
Isishwankathelo sokuseta uvavanyo lohlalutyo olukhawulezileyo lwemiqadi ye-lithium (eboniswe yi-Inkscape, 1.0.2, https://inkscape.org/).Ukusuka kwesokudla ukuya kwesobunxele, i-laser-ablative plasma yenziwa kwigumbi lokusebenzisana ne-laser-target kunye ne-linac ye-RFQ.Ekungeneni kwi-accelerator ye-RFQ, ii-ion zahlulwe kwiplasma kwaye zifakwe kwi-RFQ i-accelerator ngokusebenzisa indawo yombane yequbuliso eyenziwe ngumahluko wombane we-52 kV phakathi kwe-electrode yokutsalwa kunye ne-electrode ye-RFQ kwindawo yokukhukuliseka.Iiyoni ezikhutshiweyo zikhawuleza ukusuka kwi-22 keV/n ukuya kwi-204 keV/n kusetyenziswa ii-electrode zeRFQ eziziimitha ezi-2 ubude.I-transformer yangoku (CT) efakwe kwi-output ye-RFQ linac inikeza umlinganiselo ongonakaliyo we-ion beam current.Umqadi ugxininiswe ngamamagnethi amathathu e-quadrupole kwaye uqondiswe kwi-dipole magnet, eyahlula kwaye iqondise i-Li3 + beam kwi-detector.Emva kwe-slit, i-scintillator yeplastiki ebuyiselwayo kunye nekomityi ye-Faraday (FC) ene-bias ukuya kwi-400 V isetyenziselwa ukufumanisa i-beam ekhawulezayo.
Ukuvelisa ngokupheleleyo i-ion ze-lithium ion (Li3 +), kuyimfuneko ukudala i-plasma ngeqondo lokushisa ngaphezu kwe-ionization yesithathu yamandla (122.4 eV).Sazama ukusebenzisa i-laser ablation ukuvelisa iplasma yobushushu obuphezulu.Olu hlobo lomthombo we-laser ion alusetyenziswanga ngokuqhelekileyo ukuvelisa imiqadi ye-lithium ion kuba isinyithi se-lithium sisebenza kwaye sidinga ukuphathwa okukhethekileyo.Siye saqulunqa inkqubo yokulayisha ekujoliswe kuyo ukunciphisa umswakama kunye nokungcoliswa komoya xa ufaka i-lithium foil kwigumbi lokusebenzisana ne-vacuum laser.Zonke izilungiso zezinto zenziwe kwindawo elawulwayo ye-argon eyomileyo.Emva kokuba i-lithium foil ifakwe kwigumbi elijoliswe kuyo le-laser, i-foil yachithwa nge-pulsed Nd: i-YAG laser radiation kumandla we-800 mJ nge-pulse.Ekugxininiseni kwithagethi, ukuxinana kwamandla e-laser kuqikelelwa malunga ne-1012 W / cm2.I-Plasma yenziwa xa i-laser ye-pulsed itshabalalisa into ekujoliswe kuyo kwi-vacuum.Ngexesha lonke i-6 ns laser pulse, iplasma iyaqhubeka nokufudumala, ngokukodwa ngenxa yenkqubo ye-reverse bremsstrahlung.Ekubeni kungekho ntsimi yangaphandle ethintelweyo isetyenziswayo ngexesha lesigaba sokufudumeza, iplasma iqala ukwanda kwimilinganiselo emithathu.Xa i-plasma iqala ukwanda phezu kwendawo ekujoliswe kuyo, iziko lobunzima be-plasma lifumana i-velocity perpendicular kwindawo ekujoliswe kuyo ngamandla e-600 eV / n.Emva kokufudumeza, i-plasma iyaqhubeka ihamba kwicala le-axial ukusuka kwithagethi, yandisa isotropically.
Njengoko kuboniswe kwi-Figure 2, i-plasma yokukhupha i-ablation iyanda ibe yivolumu ye-vacuum ejikelezwe yisitya sesinyithi esinamandla afanayo kunye nokujoliswe kuyo.Ke ngoko, iplasma ikhukuliseka kwindawo engenamabala ukuya kwi-RFQ accelerator.I-axial magnetic field isetyenziswa phakathi kwegumbi le-laser irradiation kunye ne-RFQ linac ngokusebenzisa inxeba lekhoyili ye-solenoid ejikeleze igumbi lokutshayela.Ummandla wemagnethi we-solenoid ucinezela ukwanda kwe-radial yeplasma ekhukulisekayo ukuze kugcinwe uxinano oluphezulu lweplasma ngexesha lokuhanjiswa kwi-RFQ aperture.Ngakolunye uhlangothi, i-plasma iyaqhubeka ikhula kwicala le-axial ngexesha lokuhamba, isenza i-plasma emide.I-bias yamandla ombane aphezulu isetyenziswa kwinqanawa yentsimbi equlethe iplasma ephambi kwezibuko lokuphuma kwi-RFQ inlet.Umbane we-bias wakhethwa ukuba unike ireyithi yokutofa eyi-7Li3+ efunekayo yokukhawuleziswa okufanelekileyo yi-RFQ linac.
I-plasma ye-ablation enesiphumo ayiqulathanga kuphela i-7Li3+, kodwa i-lithium kwezinye iindawo zentlawulo kunye nezinto ezingcolisayo, ezihanjiswa ngaxeshanye kwi-RFQ linear accelerator.Ngaphambi kovavanyo olukhawulezayo olusebenzisa i-RFQ linac, uhlalutyo lwexesha lokuhamba ngaphandle kwe-intanethi (TOF) lwenziwa ukufundisisa ukubunjwa kunye nokusabalalisa amandla e-ion kwi-plasma.Ukuseta uhlalutyo oluneenkcukacha kunye nonikezelo olujongwayo lwe-state-of-charge luchazwe kwicandelo leeNdlela.Uhlalutyo lubonise ukuba i-7Li3 + i-ion yayiyi-particles eziphambili, ezibalelwa malunga ne-54% yazo zonke iinqununu, njengoko kuboniswe kumfanekiso 3. Ngokohlalutyo, i-7Li3 + ion yangoku kwinqanaba lokuphuma kwe-ion beam liqikelelwa kwi-1.87 mA.Ngexesha lovavanyo olukhawulezileyo, i-79 mT solenoid field isetyenziswa kwi-plasma eyandisiweyo.Ngenxa yoko, i-7Li3 + yangoku ekhutshwe kwi-plasma kwaye yabonwa kwi-detector yanda ngento ye-30.
Amacandelo e-ion kwi-plasma eyenziwe nge-laser efunyenwe ngokuhlalutya kwexesha lokuhamba.I-7Li1 + kunye ne-7Li2 + ion zenza i-5% kunye ne-25% ye-ion beam, ngokulandelanayo.Iqhekeza elifunyenweyo le-6Li particles liyavumelana nomxholo wendalo we-6Li (7.6%) kwi-target ye-lithium foil ngaphakathi kwephutha lokulinga.Ukungcola okuncinci kwe-oksijeni (6.2%) kwabonwa, ngokukodwa i-O1 + (2.1%) kunye ne-O2 + (1.5%), enokuthi ibe ngenxa ye-oxidation yobuso bethagethi ye-lithium foil.
Njengoko bekutshiwo ngaphambili, i-lithium plasma ikhukuliseka kwindawo engenamabala ngaphambi kokungena kwi-RFQ linac.Igalelo le-RFQ linac inomngxuma we-6 mm we-diameter kwi-container yesinyithi, kunye ne-voltage ye-bias yi-52 kV.Nangona amandla ombane e-electrode e-RFQ etshintsha ngokukhawuleza ±29 kV kwi-100 MHz, amandla ombane abangela i-axial acceleration ngenxa yokuba i-RFQ i-accelerator electrode ine-avareji yesakhono sika-zero.Ngenxa yommandla wombane owomeleleyo oveliswe kwisithuba se-10 mm phakathi kwe-aperture kunye nomphetho we-electrode ye-RFQ, kuphela ii-ion zeplasma ezilungileyo zitsalwa kwi-plasma kwindawo yokuvula.Kwiinkqubo zonikezelo ze-ion zemveli, ii-ion zahlulwe kwiplasma yintsimi yombane kumgama omde phambi kwe-accelerator ye-RFQ kwaye emva koko igxininise kwi-RFQ aperture nge-beam egxininise element.Nangona kunjalo, kwimiqadi ye-ion enzima efunekayo kumthombo oqinileyo we-neutron, imikhosi ye-repulsive non-linear ngenxa yemiphumo yentlawulo yendawo inokukhokelela kwilahleko ebalulekileyo ye-beam yangoku kwinkqubo yothutho ye-ion, ukunciphisa i-peak current enokuthi ikhawuleze.Kwi-DPIS yethu, ii-ion ezinzulu zithuthwa njengeplasma ekhukulisekayo ngokuthe ngqo kwindawo yokuphuma ye-RFQ aperture, ngoko akukho kulahleka kwe-ion beam ngenxa yentlawulo yendawo.Ngethuba lo mboniso, i-DPIS isetyenziswe kwi-lithium-ion beam okokuqala.
Ulwakhiwo lwe-RFQ lwaphuhliselwa ukugxila kunye nokukhawulezisa amandla aphantsi aphezulu emitha ye-ion yangoku kwaye ibe ngumgangatho wokukhawuleziswa komyalelo wokuqala.Sisebenzise i-RFQ ukukhawulezisa i-7Li3+ ion ukusuka kumandla ofakelwayo angama-22 keV/n ukuya kwi-204 keV/n.Nangona i-lithium kunye nezinye iinqununu ezinexabiso eliphantsi kwi-plasma nazo zikhutshwe kwi-plasma kwaye zifakwe kwi-RFQ aperture, i-RFQ linac ikhawuleza i-ion kunye ne-charge-to-mass ratio (Q / A) kufuphi ne-7Li3 +.
Kwikhiwane.Umzobo we-4 ubonisa iifom zamaza ezichongwe yi-transformer yangoku (CT) kwimveliso ye-RFQ linac kunye ne-Faraday cup (FC) emva kokuhlalutya imagnethi, njengoko kuboniswe kwifig.2. Ukutshintsha kwexesha phakathi kweempawu kunokutolikwa njengomahluko kwixesha lokubhabha kwindawo yesixhobo.I-peak ion current elinganiswe kwi-CT yayingu-43 mA.Kwisikhundla se-RT, i-beam ebhalisiweyo ayinakuquka kuphela i-ion ekhawulezileyo kumandla ababalwayo, kodwa kunye ne-ion ngaphandle kwe-7Li3 +, engakhawulezi ngokwaneleyo.Nangona kunjalo, ukufana kweefom zangoku ze-ion ezifunyenwe ngokusebenzisa i-QD kunye ne-PC zibonisa ukuba i-ion yangoku iquka i-accelerated 7Li3 +, kwaye ukuhla kwexabiso eliphezulu langoku kwi-PC kubangelwa yilahleko ye-beam ngexesha lokudluliselwa kwe-ion phakathi kwe-QD kunye I-PC.Ilahleko Oku kwakhona kuqinisekiswa imvulophu yokulinganisa.Ukulinganisa ngokuchanekileyo i-7Li3 + ye-beam yangoku, i-beam ihlalutywa nge-dipole magnet njengoko kuchazwe kwicandelo elilandelayo.
I-Oscillograms ye-beam ekhawulezayo erekhodwe kwizithuba ze-detector ze-CT (i-black curve) kunye ne-FC (i-red curve).Le milinganiso iqalwa kukufunyanwa kwemitha yelaser ngesisithonga seefoto ngexesha lokwenziwa kweplasma yelaser.Ijika elimnyama libonisa i-waveform elinganiswe kwi-CT eqhagamshelwe kwimveliso ye-linac ye-RFQ.Ngenxa yokuba kufutshane ne-RFQ linac, i-detector ithatha ingxolo ye-100 MHz RF, ngoko ke isihluzo se-FFT se-98 MHz sisetyenzisiwe ukususa i-100 MHz resonant RF isignali ebekwe phezulu kwisignali yokubhaqa.Ijika elibomvu libonisa i-waveform kwi-FC emva kokuba umazibuthe ohlalutyayo aqondise umqa we-ion we-7Li3+.Kulo mmandla wamagnetic, ngaphandle kwe-7Li3 +, N6 + kunye ne-O7 + inokuthuthwa.
I-ion beam emva kwe-RFQ linac igxininiswe ngoluhlu lweemagnethi ezintathu ezigxininisekileyo ze-quadrupole kwaye emva koko zihlalutywe ngamamagnethi e-dipole ukuze zihlukanise ukungcola kwi-ion beam.Intsimi yamagnetic ye-0.268 T iqondisa iiplanga ze-7Li3 + kwi-FC.I-wave waveform yalo mmandla wemagnethi iboniswa njengegophe elibomvu kuMfanekiso 4. Incopho ye-beam yangoku ifikelela kwi-35 mA, engaphezulu kwamaxesha angama-100 aphezulu kunomqadi oqhelekileyo we-Li3+ oveliswe kwii-accelerator ezikhoyo ze-electrostatic.Ububanzi be-beam pulse yi-2.0 µs kububanzi obupheleleyo kwisiqingatha esiphezulu.Ukufunyaniswa kwe-7Li3 + beam kunye ne-dipole magnetic field ibonisa impumelelo ye-bunching kunye nokukhawuleza kwe-beam.I-ion beam yangoku ifunyenwe yi-FC xa ihlola intsimi yamagnetic ye-dipole iboniswe kwi-Fig.Ekubeni zonke ii-ion ezikhawulezayo kumandla oyilo yi-RFQ linac zinesantya esifanayo, imiqadi ye-ion ene-Q/A efanayo kunzima ukwahlula nge-dipole magnetic fields.Ngoko ke, asikwazi ukwahlula i-7Li3 + kwi-N6 + okanye i-O7 +.Nangona kunjalo, isixa sobumdaka sinokuqikelelwa kumazwe angabamelwane.Ngokomzekelo, i-N7 + kunye ne-N5 + inokwahlukana ngokulula, ngelixa i-N6 + inokuba yinxalenye yokungcola kwaye kulindeleke ukuba ibe khona malunga nexabiso elifanayo ne-N7 + ne-N5 +.Inqanaba eliqikelelweyo longcoliseko limalunga ne-2%.
I-Beam component spectra efunyenwe ngokuskena i-dipole magnetic field.Incopho kwi-0.268 T ihambelana ne-7Li3 + kunye ne-N6 +.Ububanzi bencopho buxhomekeke kubukhulu bomqadi kwi-slit.Nangona iincopho ezibanzi, i-7Li3 + yohlula kakuhle kwi-6Li3 +, i-O6 +, kunye ne-N5 +, kodwa ihluke kakubi kwi-O7 + kunye ne-N6 +.
Kwindawo ye-FC, iphrofayili ye-beam yaqinisekiswa nge-plug-in scintillator kwaye irekhodwe ngekhamera yedijithali ekhawulezayo njengoko kuboniswe kuMzobo 6. I-7Li3 + i-pulsed beam kunye ne-current ye-35 mA iboniswa ukuba ikhawuleze kwi-RFQ ebalwayo. amandla e-204 keV / n, ehambelana ne-1.4 MeV, kwaye idluliselwe kwi-FC detector.
Iprofayile yeBeam ebonwe kwiscreen se-scintillator sangaphambi kweFC (enemibala yiFiji, 2.3.0, https://imagej.net/software/fiji/).Ummandla wemagnethi wemagnethi yohlalutyo lwe-dipole ulungelelaniswe ukwalathisa isantya somqadi we-ion we-Li3+ kuyilo lwamandla eRFQ.Amachaphaza aluhlaza kwindawo eluhlaza abangelwa yimpahla ye-scintillator enesiphako.
Sifezekise ukuveliswa kwe-7Li3 + ion nge-laser ablation of surface ye-lithium foil eqinile, kwaye i-ion beam ephezulu yangoku yabanjwa kwaye yakhawuleza nge-RFQ linac eyenzelwe ngokukodwa isebenzisa i-DPIS.Kumandla ombane we-1.4 MeV, i-high current ye-7Li3 + ifike kwi-FC emva kokuhlalutya kwemagnethi yayiyi-35 mA.Oku kuqinisekisa ukuba eyona nxalenye ibalulekileyo yokuphunyezwa komthombo neutron kunye kinematics inverse iphunyezwe ngokomfuniselo.Kule nxalenye yephepha, lonke uyilo lomthombo we-neutron compact luya kuxoxwa, kuquka i-accelerators yamandla aphezulu kunye nezikhululo ezijoliswe kwi-neutron.Uyilo lusekwe kwiziphumo ezifunyenweyo kunye neenkqubo ezikhoyo kwilabhoratri yethu.Kufuneka kuqatshelwe ukuba i-peak current ye-ion beam inokwandiswa ngakumbi ngokunciphisa umgama phakathi kwe-lithium foil kunye ne-RFQ linac.Irayisi.U-7 ubonisa yonke ingqikelelo yomthombo we-neutron ocetywayo kwi-accelerator.
Uyilo lombono lomthombo ocetywayo weneutron compact kwiaccelerator (etsalwa yiFreecad, 0.19, https://www.freecadweb.org/).Ukusuka ekunene ukuya ekhohlo: umthombo we-laser ion, imagnethi ye-solenoid, i-RFQ linac, ukuhanjiswa kwamandla aphakathi (MEBT), i-IH linac, kunye negumbi lokusebenzisana lokuvelisa i-neutron.Ukhuseleko lwemitha lubonelelwa ngokuyintloko kwicala langaphambili ngenxa yendalo eqondiswe emxinwa yemiqadi ye-neutron eveliswayo.
Emva kwe-RFQ linac, ukuqhubela phambili ukukhawuleza kwe-Inter-digital H-structure (IH linac)30 linac icwangcisiwe.I-IH linacs isebenzisa i-π-mode drift structure ukuze ibonelele ngeegradients zentsimi zombane eziphezulu kuluhlu oluthile lwezantya.Uphononongo lwengqikelelo lwenziwa ngokusekwe kwi-1D longitudinal dynamics simulation kunye nokulinganisa iqokobhe le-3D.Ubalo lubonisa ukuba i-100 MHz IH linac ene-voltage drift drift tube (ngaphantsi kwe-450 kV) kunye nemagnethi egxininisekileyo inokukhawulezisa i-40 mA beam ukusuka kwi-1.4 ukuya kwi-14 MeV kumgama we-1.8 m.Ukuhanjiswa kwamandla ekupheleni kwekhonkco le-accelerator kuqikelelwa kwi-± 0.4 MeV, engachaphazeli kakhulu i-spectrum yamandla e-neutron eveliswa yithagethi yokuguqulwa kwe-neutron.Ukongeza, ukukhutshwa komqadi kuphantsi ngokwaneleyo ukujolisa umqadi kwindawo encinci yomqadi kunokuba iqhele ukufunwa kumandla aphakathi kunye nobungakanani bemagnethi yequadrupole.Kuthungelwano lwamandla aphakathi (MEBT) phakathi kwe-RFQ linac kunye ne-IH linac, i-beamforming resonator isetyenziselwa ukugcina i-beamforming structure.Kusetyenziswa iimagnethi ezintathu zequadrupole ukulawula ubungakanani bomqadi osecaleni.Esi sicwangciso soyilo sisetyenziswe kwii-accelerators ezininzi31,32,33.Ubude obupheleleyo benkqubo yonke ukusuka kumthombo we-ion ukuya kwigumbi ekujoliswe kulo kuqikelelwa ukuba bungaphantsi kwe-8 m, enokungena kwilori ye-semi-trailer eqhelekileyo.
Ithagethi yokuguqulwa kwe-neutron iya kufakwa ngokuthe ngqo emva kwe-accelerator yomgca.Sixoxa ngoyilo lwesikhululo ekujoliswe kuso ngokusekwe kwizifundo zangaphambili sisebenzisa i-inverse kinematic scenarios23.Iinjongo zokuguqulwa ezixeliweyo ziquka izinto eziqinileyo (i-polypropylene (C3H6) kunye ne-titanium hydride (TiH2)) kunye neenkqubo ezijoliswe kwigesi.Injongo nganye ineengenelo nezingeloncedo.Iithagethi eziqinileyo zivumela ulawulo oluchanekileyo.Okukhona kuncipha ekujoliswe kuko, kokukhona ichaneka ngakumbi ilungiselelo lesithuba sokuveliswa kwe-neutron.Nangona kunjalo, oko kujoliswe kuko kusenokuba nomlinganiselo othile wokusabela kwenyukliya okungafunwayo kunye nemitha.Kwelinye icala, ithagethi ye-hydrogen inokubonelela ngemekobume ecocekileyo ngokuphelisa ukuveliswa kwe-7Be, eyona mveliso iphambili yokusabela kwenyukliya.Nangona kunjalo, ihydrogen inesakhono somqobo esibuthathaka kwaye ifuna umgama omkhulu womzimba wokukhupha amandla okwaneleyo.Oku kuyingozi kancinane kwimilinganiselo ye-TOF.Ukongezelela, ukuba ifilimu encinci isetyenziselwa ukutywina ithagethi ye-hydrogen, kuyimfuneko ukuqwalasela ukulahlekelwa kwamandla emitha ye-gamma eyenziwa yifilimu encinci kunye nesiganeko se-lithium beam.
I-LICORNE isebenzisa iithagethi ze-polypropylene kwaye inkqubo ekujoliswe kuyo iye yaphuculwa kwiiseli ze-hydrogen ezitywinwe nge-tantalum foil.Ukucinga ukuba i-beam current ye-100 nA ye-7Li34, zombini iinkqubo ezijoliswe kuyo zinokuvelisa ukuya kwi-107 n / s / sr.Ukuba sifaka isicelo sokuguqulwa kwesivuno se-neutron esicetywayo kumthombo wethu ocetywayo we-neutron, ke i-lithium eqhutywa ngumqadi we-7 × 10-8 C inokufumaneka kwi-pulse nganye ye-laser.Oku kuthetha ukuba ukudubula i-laser kabini nje ngomzuzwana kuvelisa ii-neutron ezingama-40% ngaphezulu kune-LICORNE inokuvelisa ngomzuzwana omnye ngomqadi oqhubekayo.I-flux epheleleyo inokunyuswa ngokulula ngokunyusa i-excitation frequency ye-laser.Ukuba sicinga ukuba kukho inkqubo yelaser ye-1 kHz kwimarike, i-avareji ye-neutron flux inokunyuswa ngokulula ukuya malunga ne-7 × 109 n/s/sr.
Xa sisebenzisa iinkqubo eziphezulu zokuphindaphinda kunye neenjongo zeplastiki, kuyimfuneko ukulawula ukuveliswa kobushushu kwiithagethi kuba, umzekelo, i-polypropylene ine-145-175 ° C ephantsi kunye ne-thermal conductivity ye-0.1-0.22 W / m/K.Kwi-14 MeV ye-lithium-ion beam, i-7 µm engqingqwa ye-polypropylene ekujoliswe kuyo yanele ukunciphisa amandla e-beam kwi-reaction threshold (13.098 MeV).Ukuqwalasela umphumo we-ion owenziwe nge-laser enye idutshulwa kwithagethi, ukukhululwa kwamandla e-lithium ion ngokusebenzisa i-polypropylene kuqikelelwa kwi-64 mJ / pulse.Ukucinga ukuba onke amandla adluliselwa kwisangqa kunye nobubanzi be-10 mm, i-pulse nganye ihambelana nokunyuka kweqondo lokushisa malunga ne-18 K / pulse.Ukukhutshwa kwamandla kwiithagethi ze-polypropylene kusekelwe kwingcinga elula yokuba zonke iilahleko zamandla zigcinwa njengobushushu, kungekho mitha okanye enye ilahleko yobushushu.Ekubeni ukwandisa inani lee-pulses ngesekhondi kufuna ukupheliswa kokwakhiwa kobushushu, sinokusebenzisa iithagethi ze-strip ukuphepha ukukhutshwa kwamandla kwindawo enye23.Ukucinga ukuba indawo ye-10 mm ye-beam kwindawo ekujoliswe kuyo kunye nesantya sokuphindaphinda kwe-laser ye-100 Hz, isantya sokuskena se-polypropylene tape siya kuba yi-1 m / s.Amazinga aphezulu okuphindaphinda anokwenzeka ukuba ukugqithelana kwendawo ye-beam kuvunyelwe.
Siphinde saphanda iithagethi ngeebhetri ze-hydrogen, kuba imiqadi eyomeleleyo yedrive ingasetyenziswa ngaphandle kokonakalisa ekujoliswe kuko.Umqadi we-neutron unokuguqulwa ngokulula ngokutshintsha ubude begumbi legesi kunye noxinzelelo lwe-hydrogen ngaphakathi.Iifoyile zetsimbi ezibhityileyo zihlala zisetyenziswa kwi-accelerator ukwahlula ummandla wegesi ekujoliswe kuwo kwi-vacuum.Ngoko ke, kuyimfuneko ukwandisa amandla esiganeko se-lithium-ion beam ukwenzela ukuhlawulela ukulahlekelwa kwamandla kwi-foil.Indibano ekujoliswe kuyo echazwe kwingxelo ye-35 yayiquka isitya se-aluminium ubude be-3.5 cm kunye noxinzelelo lwegesi ye-H2 ye-1.5 atm.I-16.75 MeV lithium ion beam ingena ebhetrini nge-air-cooled 2.7 µm Ta foil, kwaye amandla e-lithium ion beam ekupheleni kwebhetri athotyiwe ukuya kwi-reaction threshold.Ukwandisa amandla e-beam yeebhetri ze-lithium-ion ukusuka kwi-14.0 MeV ukuya kwi-16.75 MeV, i-IH linac kwafuneka yandiswe malunga ne-30 cm.
Ukukhutshwa kwee-neutron kwiithagethi zeeseli zegesi nako kwaphononongwa.Kwiithagethi zegesi ze-LICORNE ezikhankanywe ngasentla, ukulinganisa kwe-GEANT436 kubonisa ukuba i-neutron ejoliswe kakhulu iveliswa ngaphakathi kwekhoni, njengoko kubonisiwe kuMfanekiso 1 kwi- [37].Ireferensi ye-35 ibonisa uluhlu lwamandla ukusuka kwi-0.7 ukuya kwi-3.0 MeV kunye nokuvulwa kwe-cone ephezulu ye-19.5 ° ngokumalunga nolwalathiso lokusasazwa kwe-beam enkulu.I-neutron ezijoliswe kakhulu zinokunciphisa kakhulu ubungakanani bezinto ezikhuselayo kwii-engile ezininzi, ukunciphisa ubunzima besakhiwo kunye nokubonelela ukuguquguquka okukhulu ekufakeni izixhobo zokulinganisa.Ukusuka kwindawo yokujonga ukhuseleko lwemitha, ukongeza kwiineutrons, le thagethi yegesi ikhupha imitha ye-gamma ye-478 keV isotropically kwi-centroid coordinate system38.Le mitha ye-γ iveliswa ngenxa ye-7Be ukubola kunye ne-7Li deexcitation, eyenzeka xa i-primary Li beam ibetha i-input window Ta.Nangona kunjalo, ngokongeza i-35 Pb / Cu ye-cylindrical collimator engqingqwa, imvelaphi ingancitshiswa kakhulu.
Njengenye indawo ekujoliswe kuyo, umntu unokusebenzisa iwindow ye-plasma [39, 40], eyenza kube lula ukufezekisa uxinzelelo oluphezulu lwe-hydrogen kunye nommandla omncinci wendawo yokuvelisa i-neutron, nangona ingaphantsi kwiithagethi eziqinileyo.
Siphanda iinketho zokujolisa kwi-neutron yokuguqulwa kwamandla okulindelekileyo kunye nobukhulu be-beam ye-lithium ion beam usebenzisa i-GEANT4.Ukulinganisa kwethu kubonisa ukuhanjiswa okuhambelanayo kwamandla e-neutron kunye nokuhanjiswa kwe-angular kwiithagethi ze-hydrogen kwiincwadi ezingentla.Kuyo nayiphi na inkqubo ekujoliswe kuyo, i-neutron ejoliswe kakhulu inokuveliswa yi-inverse kinematic reaction eqhutywa yi-7Li3 + eqinile kwithagethi ye-hydrogen-rich.Ke ngoko, imithombo emitsha ye-neutron inokuphunyezwa ngokudibanisa ubugcisa obusele bukhona.
Iimeko ze-laser irradiation ziphinde zavelisa iimvavanyo zokuvelisa i-ion beam ngaphambi komboniso okhawulezileyo.I-laser yi-desktop nanosecond Nd: inkqubo ye-YAG ene-laser power density ye-1012 W / cm2, i-wavelength esisiseko ye-1064 nm, indawo yamandla ye-800 mJ, kunye nobude be-pulse ye-6 ns.Idayamitha yendawo ekujoliswe kuyo iqikelelwa kwi-100 µm.Ngenxa yokuba isinyithi se-lithium (i-Alfa Aesar, i-99.9% esulungekileyo) ithambile kakhulu, izinto ezisikwe ngokuchanekileyo zicinezelwa kwi-mold.Imilinganiselo ye-Foil 25 mm × 25 mm, ubukhulu be-0.6 mm.Umonakalo ofana neCrater wenzeka kumphezulu wenjongo ekujoliswe kuyo xa i-laser ibetha kuyo, ngoko ekujoliswe kuko kushukunyiswa liqonga lemoto ukubonelela ngenxalenye entsha yendawo ekujoliswe kuyo ngokudubula kwelaser nganye.Ukuze ugweme ukuhlanganiswa kwakhona ngenxa yegesi eshiyekileyo, uxinzelelo lwegumbi lugcinwe ngaphantsi koluhlu lwe-10-4 Pa.
Umthamo wokuqala we-laser plasma uncinci, ekubeni ubungakanani bendawo ye-laser yi-100 μm kwaye ngaphakathi kwe-6 ns emva kwesizukulwana sayo.Umthamo ungathathwa njengenqaku elichanekileyo kwaye landiswe.Ukuba i-detector ibekwe kumgama xm ukusuka kwindawo ekujoliswe kuyo, ngoko umqondiso ofunyenweyo uthobela ubudlelwane: i-ion yangoku I, ixesha lokufika kwe-ion t, kunye nobubanzi be-pulse τ.
I-plasma eyenziwe yafundwa ngendlela ye-TOF kunye ne-FC kunye ne-ion analyzer (EIA) ehlala kumgama we-2.4 m kunye ne-3.85 m ukusuka kwithagethi ye-laser.I-FC inegridi yomcinezeli ethambekele kwi -5 kV ukuthintela ii-electron.I-EIA ine-90 degree electrostatic deflector ebandakanya i-electrode yentsimbi ye-coaxial cylindrical enamandla ombane afanayo kodwa i-polarity echaseneyo, ilungile ngaphandle kunye ne-negative ngaphakathi.I-plasma eyandisiweyo iqondiswe kwi-deflector emva kwe-slot kwaye igxothwe yintsimi yombane edlula kwi-cylinder.Iion ezanelisayo ubudlelwane E/z = i-eKU zichongiwe kusetyenziswa iSecondary Electron Multiplier (SEM) (Hamamatsu R2362), apho u-E, z, e, K, kunye no-U amandla e-ion, imeko yentlawulo, kunye nentlawulo yi-EIA geometric factor. .ii-electron, ngokulandelelana, kunye nokwahlukana okunokwenzeka phakathi kwee-electrode.Ngokutshintsha i-voltage kwi-deflector, umntu unokufumana amandla kunye nokusabalalisa i-ion kwi-plasma.I-voltage yokutshayela i-U/2 EIA ikuluhlu ukusuka kwi-0.2 V ukuya kwi-800 V, ehambelana namandla e-ion kuluhlu olusuka kwi-4 eV ukuya kwi-16 keV kwimeko yentlawulo.
Ukuhanjiswa kwemeko yentlawulo ye-ion ehlalutywe phantsi kweemeko ze-laser irradiation echazwe kwicandelo elithi "Isizukulwana se-lithium ehluthwe ngokupheleleyo" iboniswe kwiMifanekiso.8.
Uhlalutyo lokusasazwa kobume bentlawulo yeeoni.Nantsi iprofayile ye-ion yangoku yoxinaniso lwexesha elihlalutywe nge-EIA kwaye ilinganiswe kwi-1 m ukusuka kwi-lithium foil usebenzisa i-equation.(1) kunye (2).Sebenzisa iimeko ze-laser irradiation ezichazwe kwicandelo elithi "Isizukulwana se-Lithium Beam ngokuPheleleyo".Ngokudibanisa uxinaniso ngalunye lwangoku, umlinganiselo we-ion kwi-plasma ubalwa, uboniswe kuMfanekiso 3.
Imithombo ye-ion ye-Laser inokuhambisa i-ion beam ye-multi-mA enzima kunye nentlawulo ephezulu.Nangona kunjalo, ukuhanjiswa komqadi kunzima kakhulu ngenxa yokurhoxiswa kwentlawulo yendawo, ngoko ke akuzange kusetyenziswe ngokubanzi.Kwiskimu semveli, imiqadi ye-ion itsalwa kwiplasma kwaye ithuthwa isiwe kwi-accelerator ephambili ecaleni komgca we-beam kunye neemagnethi ezininzi ezigxininisekileyo ukubumba umqa we-ion ngokwesakhono sokuthatha i-accelerator.Kwimiqadi yamandla entlawulo esithubeni, imiqadi iyahlukana ngokungeyo-layini, kwaye kujongwe ilahleko enzulu yemiqadi, ngakumbi kwingingqi yezantya eziphantsi.Ukoyisa le ngxaki ekuphuhlisweni kwee-accelerators zekhabhoni zonyango, kucetywa iskim esitsha sokuhanjiswa kwebholi ye-DPIS41.Siye sasebenzisa obu buchule ukukhawulezisa umqadi lithium-ion enamandla ukusuka kumthombo entsha neutron.
Njengoko kubonisiwe kwifig.I-4, indawo apho i-plasma yenziwe kwaye yandiswa ijikelezwe yisitya sesinyithi.Indawo evaliweyo ifikelela ekungeneni kwi-resonator ye-RFQ, kubandakanywa nomthamo ngaphakathi kwekhoyili ye-solenoid.Kwafakwa amandla ombane angama-52 kV kwisikhongozeli.Kwiresonator yeRFQ, iiyoni zitsalwa ngokunokubakho ngomngxuma oyi-6 mm ubukhulu ngokumisa iRFQ.Imikhosi echasayo engabonakaliyo kumgca we-beam iyacinywa njengoko i-ion ihanjiswa kwi-plasma state.Ukongezelela, njengoko kukhankanyiwe ngasentla, sisebenzise intsimi ye-solenoid ngokudibanisa ne-DPIS ukulawula nokwandisa ubuninzi bee-ion kwi-aperture yokukhupha.
I-accelerator ye-RFQ iquka igumbi lokufunxa cylindrical njengoko kubonisiwe kwifig.9a.Ngaphakathi kwayo, iintonga ezine zethusi ezingenayo i-oxygen zibekwe i-quadrupole-symmetrically malunga ne-axis ye-beam (Umfanekiso 9b).Iintonga ezi-4 kunye namagumbi zenza i-resonant RF circuit.Ummandla we-RF owenziweyo wenza i-voltage eguquguqukayo yexesha kwintonga.Iiyoni ezimiliselwe ngobude ngokujikeleze i-axis zibanjwa ecaleni ngebala le-quadrupole.Ngexesha elifanayo, incam yentonga imodulated ukudala intsimi yombane ye-axial.Intsimi ye-axial iyahlula i-injected beam eqhubekayo ibe yichungechunge lwee-pulses ze-beam ezibizwa ngokuba yi-beam.Umqadi ngamnye uqulethwe kwixesha elithile lomjikelo weRF (10 ns).Imiqadi emeleneyo ibekwe ngokwexesha lerediyo.Kwi-RFQ linac, i-2 µs beam evela kumthombo we-ion ye-laser iguqulwa ibe kulandelelwano lwe-200 yemitha.Umqadi ke ukhawulezelwa kumandla abalwayo.
Umyinge we-accelerator RFQ.(a) (ekhohlo) Imboniselo yangaphandle ye-RFQ linac chamber.(b) (ekunene) I-electrode enentonga ezine kwigumbi.
Eyona parameters yoyilo lwe-RFQ linac yivoltheji yentonga, iresonant frequency, beam hole radius, kunye ne-electrode modulation.Khetha amandla ombane kwintonga ± 29 kV ukuze indawo yayo yombane ibe ngaphantsi komda wokuqhekeka kombane.Okukhona kusezantsi i-resonant frequency, kokukhona amandla okujolisa ngasecaleni abe mancinci kwaye abe mancinci ibala lokukhawulezisa eliphakathi.I-radii enkulu yokuvula yenza ukuba kwenzeke ukunyusa ubungakanani be-boam kwaye, ngenxa yoko, ukwandisa umqadi wangoku ngenxa yokunyanzeliswa kwentlawulo yendawo encinci.Kwelinye icala, iradio enkulu yokuvula ifuna amandla amaninzi eRF ukunika amandla iRFQ linac.Ukongezelela, inqunyelwe ngeemfuno zomgangatho wesayithi.Ngokusekwe kwezi zilinganisi, i-resonant frequency (100 MHz) kunye neradiyasi yokuvula (4.5 mm) zikhethelwe ukukhawulezisa umqadi wangoku.Ukumodareyitha kukhethwe ukunciphisa ilahleko ye-beam kunye nokwandisa ukusebenza kakuhle kwesantya.Uyilo luye lwaphuculwa amaxesha amaninzi ukuvelisa i-RFQ yoyilo lwelinac olunokukhawulezisa i-7Li3 + ion kwi-40 mA ukusuka kwi-22 keV / n ukuya kwi-204 keV / n ngaphakathi kwe-2 m.Amandla eRF alinganiswe ngexesha lovavanyo ayengama-77 kW.
I-linacs ye-RFQ inokukhawulezisa i-ion kunye noluhlu oluthile lwe-Q / A.Ngoko ke, xa uhlalutya i-beam eyondliwe ukuya ekupheleni kwe-accelerator yomgca, kuyimfuneko ukuqwalasela i-isotopes kunye nezinye izinto.Ukongeza, iiyoni ezifunwayo, eziye zakhawuleziswa ngokuyinxenye, kodwa zehla phantsi kweemeko zokukhawulezisa phakathi kwe-accelerator, zisenokudibana nokuvalwa kwecala kwaye zinokuthuthwa kude kube sekupheleni.Imitha engafunekiyo ngaphandle kwamasuntswana enziwe ngobunjineli angama-7Li3+ abizwa ngokuba bubumdaka.Kwiimvavanyo zethu, ukungcola kwe-14N6 + kunye ne-16O7 + kwakuyeyona nto ixhalabisa kakhulu, ekubeni i-lithium metal foil isabela nge-oxygen kunye ne-nitrogen emoyeni.Ezi ion zinomlinganiselo we-Q/A onokukhawuleziswa nge-7Li3+.Sisebenzisa iimagnethi ze-dipole ukwahlula imiqadi yomgangatho owahlukileyo kunye nomgangatho wokuhlalutya umqadi emva kwe-RFQ linac.
Umgca we-beam emva kwe-RFQ linac yenzelwe ukuhambisa umqadi we-7Li3 + okhawulezayo ngokupheleleyo kwi-FC emva kwemagnethi ye-dipole.-I-400 V i-electrodes ye-bias isetyenziselwa ukucinezela ii-electron zesibini kwindebe ukulinganisa ngokuchanekileyo i-ion beam yangoku.Ngalo optics, i-ion trajectories yahlulwe kwi-dipoles kwaye igxininise kwiindawo ezahlukeneyo ngokuxhomekeke kwi-Q / A.Ngenxa yezinto ezahlukeneyo ezinje ngokusasazwa kwesantya kunye nokurhoxiswa kwentlawulo yendawo, umqadi ekugxilwe kuwo unobubanzi obuthile.Uhlobo lunokwahlulwa kuphela ukuba umgama phakathi kweendawo ekugxilwe kuzo zeentlobo ezimbini ze-ion mkhulu kunobubanzi bomqadi.Ukufumana isisombululo esiphezulu esinokwenzeka, i-slit ethe tyaba ifakwe kufuphi nesinqe se-boam, apho umqadi ugxininiswe ngokufanelekileyo.Isikrini se-scintillation (CsI (Tl) esivela eSaint-Gobain, i-40 mm × 40 mm × 3 mm) ifakwe phakathi kwe-slit kunye ne-PC.I-scintillator yayisetyenziselwa ukumisela esona sikhewu sincinci ekufuneka amasuntswana ayiliweyo agqithe kuso ukuze kusonjululwe ngokupheleleyo kunye nokubonisa ubungakanani beam obamkelekileyo bemiqadi ye-ion enzima yangoku.Umfanekiso womqadi kwi-scintillator urekhodwa yikhamera yeCCD ngefestile yevacuum.Lungisa ifestile yexesha lokuvezwa ukugquma bonke ububanzi be-beam pulse.
Iisethi zedatha ezisetyenzisiweyo okanye ezihlalutyiweyo kuphononongo lwangoku ziyafumaneka kubabhali abachaphazelekayo ngesicelo esifanelekileyo.
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