304L 6.35 * 1mm Abatanga ibyuma bitagira umuyonga, Kwerekana urumuri rukomeye rwa lithium yo kubyara neutron itaziguye.

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Nubundi buryo bwo kwiga kubyerekeranye na reaction ya nucleaire, moteri yihuta itwarwa na neutron generator ikoresha umushoferi wa lithium-ion beam ishobora kuba umukandida utanga ikizere kuko itanga imirasire idakenewe.Ariko rero, byari bigoye gutanga urumuri rukomeye rwa lithium ion, kandi gukoresha ibikoresho nkibi byafatwaga nkibidashoboka.Ikibazo gikomeye cyane cyimyuka idahagije yakemuwe no gukoresha plasma itaziguye.Muri iyi gahunda, plasma yuzuye ya plasma yakozwe na lazeri yo gukuraho icyuma cya lithium fayili yatewe neza kandi yihutishwa numuvuduko mwinshi wa quadrupole yihuta (yihuta ya RFQ).Twageze kumurongo wamashanyarazi ya mA 35 yihuta kugera kuri 1.43 MeV, ni amategeko abiri yubunini burenze inshinge zisanzwe hamwe na sisitemu yihuta ishobora gutanga.
Bitandukanye na X-imirasire cyangwa ibice byashizwemo, neutron ifite ubujyakuzimu bunini bwinjira hamwe n’imikoranire idasanzwe hamwe n’ibintu byegeranye, bigatuma iba probe zitandukanye cyane zo kwiga imiterere yibikoresho1,2,3,4,5,6,7.By'umwihariko, tekinoroji ya neutron ikoreshwa muburyo bwo kwiga ibigize, imiterere, hamwe nihungabana ryimbere mubintu byegeranye kandi birashobora gutanga amakuru arambuye kubyerekeranye nuruvange rwimyunyu ngugu yibyuma bigoye kubimenya ukoresheje X-ray spectroscopy8.Ubu buryo bufatwa nkigikoresho gikomeye mubumenyi bwibanze kandi bukoreshwa nabakora ibyuma nibindi bikoresho.Vuba aha, neutron itandukanya yakoreshejwe kugirango hamenyekane impungenge zisigaye mubice bya mashini nka gari ya moshi nibice 9,10,11,12.Neutron nayo ikoreshwa mumariba ya peteroli na gaze kuko ifatwa byoroshye nibikoresho bikungahaye kuri proton13.Uburyo nkubwo bukoreshwa no mubwubatsi.Ikizamini cya neutron kidasenya ni igikoresho cyiza cyo kumenya amakosa yihishe mu nyubako, tunel n'ibiraro.Gukoresha ibiti bya neutron bikoreshwa cyane mubushakashatsi bwa siyansi n’inganda, ibyinshi muri byo bikaba byarakozwe mu mateka hakoreshejwe ingufu za kirimbuzi.
Ariko, hamwe n’ubwumvikane bw’isi yose ku bijyanye no kudakwirakwiza ingufu za kirimbuzi, kubaka reakteri ntoya hagamijwe ubushakashatsi biragenda bigorana.Byongeye kandi, impanuka ya Fukushima iherutse yatumye kubaka reaction za kirimbuzi hafi ya byose byemewe.Kubijyanye niyi nzira, ibyifuzo bya neutron biva kwihuta biriyongera2.Nkubundi buryo bwa reaction ya nucleaire, amasoko manini yihuta-agabanya neutron isoko yamaze gukora14,15.Nyamara, kugirango ukoreshe neza umutungo wibiti bya neutron, birakenewe kwagura imikoreshereze yinkomoko yihuta kuri moteri yihuta, 16 ishobora kuba iyikigo cyubushakashatsi bwinganda na kaminuza.Inkomoko yihuta ya neutron yongeyeho ubushobozi nibikorwa bishya usibye kuba umusimbura wa reaction za kirimbuzi14.Kurugero, moteri ikoreshwa na linac irashobora gukora byoroshye urujya n'uruza rwa neutron mugukoresha urumuri rwa disiki.Iyo zimaze gusohoka, neutron ziragoye kugenzura kandi gupima imirasire biragoye kubisesengura kubera urusaku rwatewe na neutron.Gusunika neutron bigenzurwa nihuta wirinde iki kibazo.Imishinga myinshi ishingiye ku buhanga bwa proton yihuta yatanzwe ku isi 17,18,19.Imyitwarire 7Li (p, n) 7Be na 9Be (p, n) 9B ikoreshwa cyane mumashanyarazi ya proton ikoreshwa na generator ya neutron kuko ni reaction ya endothermic20.Imirasire irenze urugero hamwe n imyanda ya radio irashobora kugabanuka mugihe ingufu zahisemo gushimisha urumuri rwa proton ziri hejuru gato yagaciro kinjira.Nyamara, ubwinshi bwintego nucleus nini nini cyane kuruta ya proton, kandi neutron zavuyemo ziratatana mubyerekezo byose.Ibintu byegereye imyuka ya isotropique ya neutron flux birinda gutwara neza neutron mubintu byo kwiga.Byongeye kandi, kugirango ubone igipimo gikenewe cya neutron aho kiri, ni ngombwa kongera cyane umubare wimikorere ya proton ningufu zabo.Nkigisubizo, ingano nini yimirasire ya gamma na neutron bizakwirakwira binyuze munzira nini, byangiza ibyiza bya reaction ya endothermic.Ubusanzwe umuvuduko wihuta utwarwa na proton-ishingiye kuri neutron generator ifite imishwarara ikomeye ikingira kandi nigice kinini cya sisitemu.Gukenera kongera ingufu zo gutwara proton mubisanzwe bisaba kwiyongera kwinyongera mubunini bwikigo cyihuta.
Kugira ngo tuneshe ibitagenda neza muri rusange bituruka kuri neutron isanzwe yihuta, hashyizweho gahunda yo guhinduranya inversion-kinematike21.Muri iyi gahunda, urumuri ruremereye rwa lithium-ion rukoreshwa nk'urumuri ruyobora aho kuba urumuri rwa proton, rugamije ibikoresho bikungahaye kuri hydrogène nka plastiki ya hydrocarubone, hydride, gaze ya hydrogène, cyangwa plasma ya hydrogen.Ibindi byasuzumwe, nkibiti bya beryllium ion, ariko, beryllium nikintu cyuburozi gisaba ubwitonzi bwihariye mugukemura.Kubwibyo, urumuri rwa lithium nirwo rukwiranye na inversion-kinematic reaction.Kubera ko umuvuduko wa lithium nuclei uruta uw'ama proton, hagati ya misa yo kugongana kwa kirimbuzi ihora itera imbere, kandi na neutron nazo zisohoka imbere.Iyi mikorere ikuraho cyane imirasire ya gamma idakenewe hamwe nu mwuka mwinshi wa neutron.Kugereranya ikibazo gisanzwe cya moteri ya proton hamwe na kinematiki ihindagurika irerekanwa mumashusho 1.
Ishusho yerekana ingirabuzimafatizo ya neutron kumirasire ya proton na lithium (yashushanijwe na Adobe Illustrator CS5, 15.1.0, https://www.adobe.com/products/illustrator.html)...
Nyamara, amashanyarazi make ya kinematike ya neutron gusa arahari kubera ingorane zo kubyara flux zisabwa za ion ziremereye hamwe numuriro mwinshi ugereranije na proton.Ibi bimera byose bikoresha sputter ion inkomoko ifatanije na tandem electrostatike yihuta.Ubundi bwoko bwa ion butangwa bwasabwe kongera imikorere yihuta ryibiti26.Ibyo ari byo byose, lithium-ion iboneka ihari igarukira kuri 100 µA.Hasabwe gukoresha mA 1 ya Li3 + 27, ariko ubu buryo bwa ion beam ntabwo byemejwe nubu buryo.Kubijyanye nuburemere, umuvuduko wa lithium beam ntishobora guhangana na moteri yihuta ya proton ifite impanuka ya proton irenga mA28.
Kugirango ushyire mubikorwa amashanyarazi ya neutron ashingiye kumurongo wa lithium-ion, nibyiza kubyara ubukana bwinshi butagira ion.Iyoni yihuta kandi ikayoborwa nimbaraga za electromagnetic, kandi urwego rwohejuru rushobora kwihuta cyane.Abashoferi ba Li-ion bakeneye Li3 + impinga zirenga 10 mA.
Muriyi mirimo, turerekana kwihuta kwamashanyarazi ya Li3 + hamwe ningaruka zimpinga zigera kuri mA 35, ibyo bikaba bigereranywa na moteri yihuta ya proton.Umwimerere wa lithium ion beam wakozwe hifashishijwe gukuraho laser hamwe na Direct Plasma Implantation Scheme (DPIS) byakozwe mbere kugirango byihute C6 +.Ikirangantego cyateguwe na radiyo yumurongo wa quadrupole linac (RFQ linac) yahimbwe ikoresheje imiterere yinkoni enye.Twagenzuye ko urumuri rwihuta rufite ingufu zibarwa zifite ingufu nyinshi.Iyo urumuri rwa Li3 + rumaze gufatwa neza no kwihuta na radiyo yihuta ya radiyo (RF), igice cyakurikiyeho linac (yihuta) gikoreshwa mugutanga ingufu zikenewe kugirango habeho ingufu za neutron zikomeye ziva kumugambi.
Kwihuta kwimikorere ikomeye ion nubuhanga bwashizweho neza.Igikorwa gisigaye cyo kumenya amashanyarazi mashya ya neutron akora cyane ni ugukora umubare munini wa lithium ion yambuwe burundu hanyuma ugakora cluster igizwe nurukurikirane rwa ion pulses ihujwe na cycle ya RF muri moteri yihuta.Ibisubizo byubushakashatsi bugamije kugera kuriyi ntego byasobanuwe mu bice bitatu bikurikira: (1) igisekuru kidafite rwose ibiti bya lithium-ion, (2) kwihuta kumurabyo ukoresheje linike yabugenewe idasanzwe, na (3) kwihutisha isesengura cy'igiti cyo kugenzura ibirimo.Muri Laboratwari ya Brookhaven (BNL), twubatsemo igeragezwa ryerekanwe ku gishushanyo cya 2.
Incamake yuburyo bwikigereranyo bwo gusesengura byihuse ibiti bya lithium (bigaragazwa na Inkscape, 1.0.2, https://inkscape.org/).Uhereye iburyo ujya ibumoso, plasma-ablative plasma ikorerwa mucyumba cya laser-target imikoranire kandi igashyikirizwa linac ya RFQ.Iyo winjiye muri moteri ya RFQ, ion zitandukanijwe na plasma hanyuma zinjizwa mumashanyarazi ya RFQ binyuze mumashanyarazi atunguranye yakozwe na 52 kV itandukanya itandukaniro hagati ya electrode ikuramo na electrode ya RFQ mukarere ka drift.Iyoni yakuweho yihuta kuva kuri 22 keV / n kugeza kuri 204 keV / n ukoresheje metero 2 z'uburebure bwa electrode ya RFQ.Impinduramatwara igezweho (CT) yashyizwe mubisohoka bya linac ya RFQ itanga ibipimo bidasenya ibipimo bya ion beam.Igiti cyibanze kuri magneti eshatu za kane kandi zerekeza kuri magneti dipole, itandukanya kandi ikayobora urumuri rwa Li3 + muri detector.Inyuma yikibice, scintillator ya plastike ikururwa hamwe nigikombe cya Faraday (FC) hamwe no kubogama kugera kuri -400 V bikoreshwa mugushakisha urumuri rwihuta.
Kugirango habeho ioni yuzuye ya lithium (Li3 +), birakenewe gukora plasma ifite ubushyuhe buri hejuru yingufu zayo za gatatu ionisiyoneri (122.4 eV).Twagerageje gukoresha lazeri kugirango tubone plasma yubushyuhe bwo hejuru.Ubu bwoko bwa lazeri ion ntabwo bukoreshwa muburyo bwo kubyara ibiti bya lithium kuko ibyuma bya lithium bikora kandi bisaba gukora bidasanzwe.Twateje imbere uburyo bwo gupakira ibintu kugirango tugabanye ubushuhe hamwe n’umwuka uhumanya mugihe dushyira lithium foil mu cyumba cyimikoranire ya vacuum.Gutegura ibikoresho byose byakorewe ahantu hagenzurwa na argon yumye.Nyuma ya lithium foil imaze gushyirwa mucyumba cyerekanwe cya laser, fayili yashizwemo imirasire Nd: YAG laser laser ku mbaraga za 800 mJ kuri pulse.Kwibanda ku ntego, ubucucike bwa laser bugereranywa na 1012 W / cm2.Plasma ikorwa mugihe laser ya pulsed isenya intego mumyuka.Mugihe cyose 6 ns laser pulse, plasma ikomeza gushyuha, bitewe ahanini na bremsstrahlung inzira.Kubera ko nta murima wo hanze ukoreshwa mugihe cyo gushyushya, plasma itangira kwaguka mubice bitatu.Iyo plasma itangiye kwaguka hejuru yintego, hagati ya misa ya plasma ibona umuvuduko utambitse hejuru yintego hamwe ningufu za 600 eV / n.Nyuma yo gushyushya, plasma ikomeza kugenda yerekeza mu cyerekezo cya axial kuva ku ntego, yaguka isotropically.
Nkuko bigaragara ku gishushanyo cya 2, plasma yo gukuramo yaguka mubunini bwa vacuum ikikijwe nicyuma gifite ubushobozi bumwe nkintego.Rero, plasma iranyura mukarere katarangwamo umurima werekeza umuvuduko wa RFQ.Umwanya wa magnetiki wa axial ushyirwa hagati yicyumba cya lazeri ya lazeri na linac ya RFQ hakoreshejwe igikomere cya solenoid coil gikikije icyumba cya vacuum.Umwanya wa rukuruzi ya solenoid uhagarika kwaguka kwinshi kwa plasma igenda kugirango hagumane ubwinshi bwa plasma mugihe cyo kugeza kuri RFQ aperture.Ku rundi ruhande, plasma ikomeza kwaguka mu cyerekezo cya axial mugihe cya drift, ikora plasma ndende.Kubogama kwinshi cyane kubikoresho byicyuma kirimo plasma imbere yicyambu cyo gusohoka kuri enterineti ya RFQ.Umuvuduko wa bias watoranijwe kugirango utange igipimo cya 7Li3 + gisabwa kugirango wihute neza na RFQ linac.
Plasma yo gukuramo ibivamo ntabwo irimo 7Li3 + gusa, ahubwo irimo na lithium mubindi bihugu byishyuza hamwe n’ibintu bihumanya, bijyanwa icyarimwe kuri moteri yihuta ya RFQ.Mbere yubushakashatsi bwihuse ukoresheje linac ya RFQ, hakozwe isesengura ryigihe-cyo guhaguruka (TOF) kugirango ryige imiterere nogukwirakwiza ingufu za ion muri plasma.Ibisobanuro birambuye byisesengura kandi byarebwaga na leta-yishyurwa bisobanurwa mu gice cyuburyo.Isesengura ryerekanye ko 7Li3 + ion ari zo ngingo nyamukuru, zingana na 54% by’ibice byose, nkuko bigaragara ku gishushanyo cya 3. Nk’uko isesengura ryabigaragaje, umuyoboro wa 7Li3 + ion ku cyerekezo cya ion beam ugera kuri 1.87 mA.Mugihe cyibizamini byihuse, umurima wa 79 mT solenoid ukoreshwa kuri plasma yaguka.Nkigisubizo, amashanyarazi ya 7Li3 + yakuwe muri plasma kandi akareba kuri detector yiyongereyeho 30.
Ibice bya ion muri plasma yakozwe na laser yabonetse mugihe cyo guhaguruka.7Li1 + na 7Li2 + ion zigize 5% na 25% bya ion beam.Igice cyagaragaye cyibice 6Li cyemeranya nibintu bisanzwe bya 6Li (7,6%) mumigambi ya lithium foil mumakosa yubushakashatsi.Umwuka wa ogisijeni muto (6.2%) wagaragaye, cyane cyane O1 + (2,1%) na O2 + (1.5%), ibyo bikaba bishobora guterwa na okiside yubuso bwa lithium foil.
Nkuko byavuzwe haruguru, plasma ya lithium igenda mu karere katagira umurima mbere yo kwinjira muri linac ya RFQ.Iyinjiza rya linac ya RFQ ifite umwobo wa mm 6 ya diametre mu cyuma, naho voltage ya bias ni 52 kV.Nubwo amashanyarazi ya RFQ ya electrode ahinduka byihuse ± 29 kV kuri 100 MHz, voltage itera kwihuta kwinshi kuko electrode yihuta ya RFQ ifite impuzandengo ya zeru.Bitewe n'umuriro w'amashanyarazi ukomeye wabyaye mu cyuho cya mm 10 hagati ya aperture no ku nkombe ya electrode ya RFQ, gusa ion nziza za plasma zivanwa muri plasma kuri aperture.Muri sisitemu yo gutanga ion gakondo, ion zitandukanijwe na plasma numurima wamashanyarazi intera nini imbere yumuvuduko wa RFQ hanyuma ukerekeza muri aperture ya RFQ nikintu cyibanda kumurongo.Nyamara, kumirasire iremereye ya ion isabwa kumasoko akomeye ya neutron, imbaraga zidafite umurongo zitera umurongo bitewe ningaruka zogukoresha ikirere zishobora gutera igihombo kinini mumashanyarazi muri sisitemu yo gutwara ion, bikagabanya umuvuduko wimpanuka ushobora kwihuta.Muri DPIS yacu, ion zifite ubukana bwinshi zitwarwa nka plasma igenda yerekeza aho isohokera ya RFQ aperture, bityo rero ntihabuze igihombo cya ion kubera kwishyurwa n'umwanya.Muri iyi myiyerekano, DPIS yakoreshejwe kumurongo wa lithium-ion bwa mbere.
Imiterere ya RFQ yatunganijwe kugirango yibande kandi yihutishe ingufu nkeya za ion beam kandi ibaye ihame ryihuta ryambere.Twifashishije RFQ kugirango twihute 7Li3 + ion kuva ingufu zatewe 22 keV / n kugeza 204 keV / n.Nubwo lithium nibindi bice bifite umuriro muke muri plasma nabyo bivanwa muri plasma hanyuma bigaterwa muri aperture ya RFQ, linac ya RFQ yihutisha ion gusa hamwe nikigereranyo cyinshi (Q / A) hafi ya 7Li3 +.
Ku mutini.Igishushanyo cya 4 cyerekana imiterere yumurongo wamenyekanye na transformateur iriho ubu (CT) kumusaruro wa linac ya RFQ hamwe nigikombe cya Faraday (FC) nyuma yo gusesengura magneti, nkuko bigaragara mumitini.2. Guhindura umwanya hagati yibimenyetso birashobora gusobanurwa nkitandukaniro mugihe cyindege aho indege ikorera.Umuyoboro wa ion wapimwe kuri CT wari 43 mA.Mu mwanya wa RT, urumuri rwanditse ntirushobora kubamo ion gusa yihuta ku mbaraga zabazwe, ariko kandi ion zitari 7Li3 +, zitihuta cyane.Ariko, guhuza imiterere ya ion iriho iboneka hakoreshejwe QD na PC byerekana ko ion ya ion igizwe ahanini nihuta 7Li3 +, kandi igabanuka ryagaciro ryibihe byumuyaga kuri PC riterwa no gutakaza ibiti mugihe cyo kohereza ion hagati ya QD na PC.Igihombo Ibi kandi byemezwa no kwigana ibahasha.Kugirango upime neza 7Li3 + urumuri, urumuri rusesengurwa hamwe na magneti dipole nkuko byasobanuwe mugice gikurikira.
Oscillogrammes yumurongo wihuse wanditse mumwanya wa detector CT (umurongo wumukara) na FC (umurongo utukura).Ibi bipimo biterwa no kumenya imirasire ya laser na fotodetector mugihe cyo kubyara plasma.Umukara wirabura werekana umurongo wapimwe kuri CT uhujwe na RFQ linac isohoka.Bitewe nuko yegereye linac ya RFQ, detector ifata urusaku rwa 100 MHz RF, bityo hashyizweho akayunguruzo ka 98 MHz gato ya FFT kugirango ikureho ikimenyetso cya 100 MHz resonant RF cyashyizwe hejuru yikimenyetso.Umurongo utukura werekana imiterere ya FC nyuma ya magneti yisesengura ayobora urumuri rwa 7Li3 +.Muri uyu murima wa magneti, usibye 7Li3 +, N6 + na O7 + birashobora gutwarwa.
Ion beam nyuma ya linac ya RFQ yibanda kumurongo wa quadrupole eshatu yibanda kuri magnesi hanyuma igasesengurwa na magneti dipole kugirango itandukanya umwanda mumirasire ya ion.Umwanya wa magneti wa 0.268 T uyobora imirongo ya 7Li3 + muri FC.Imiterere yo gutahura yumurima wa magneti yerekanwa nkumurongo utukura ku gishushanyo cya 4. Umuyoboro wamashanyarazi ugera kuri mA 35, ukaba wikubye inshuro zirenga 100 kurenza urumuri rusanzwe rwa Li3 + rwakozwe mumashanyarazi asanzwe yihuta.Ubugari bwa beam pulse ni 2.0 µs mubugari bwuzuye kuri kimwe cya kabiri ntarengwa.Kumenya urumuri rwa 7Li3 + hamwe na magneti ya dipole yerekana ko bigenda neza kandi byihuta.Umuyoboro wa ion urumuri wagaragajwe na FC mugihe wasuzumye umurima wa magneti wa dipole werekana ku gishushanyo cya 5. Impinga imwe isukuye yagaragaye, itandukanijwe neza nizindi mpinga.Kubera ko ion zose zihutishije ingufu zishushanya na RFQ linac zifite umuvuduko umwe, imirishyo ya ion hamwe na Q / A biragoye gutandukanya na dipole magnetique.Ntabwo rero, ntidushobora gutandukanya 7Li3 + na N6 + cyangwa O7 +.Nyamara, ingano y’umwanda irashobora kugereranywa uhereye mubihugu bituranye.Kurugero, N7 + na N5 + birashobora gutandukana byoroshye, mugihe N6 + ishobora kuba igice cyumwanda kandi biteganijwe ko izaboneka hafi yingana na N7 + na N5 +.Ikigereranyo cy’umwanda ugereranije ni 2%.
Ibice bigize urumuri rwabonetse mugusikana dipole magnetique.Impinga kuri 0.268 T ihuye na 7Li3 + na N6 +.Ubugari bwa mpinga buterwa nubunini bwibiti kumurongo.Nubwo impinga nini, 7Li3 + itandukanya neza na 6Li3 +, O6 +, na N5 +, ariko itandukana nabi na O7 + na N6 +.
Aho FC iherereye, umwirondoro wibiti byemejwe hamwe na plug-in scintillator hanyuma yandikwa hamwe na kamera yihuta ya digitale nkuko bigaragara ku gishushanyo cya 6. 7Li3 + yamashanyarazi ifite amashanyarazi ya mA 35 yerekanwe ko yihuta kuri RFQ yabazwe ingufu za 204 keV / n, zihwanye na 1.4 MeV, kandi zoherejwe kuri detector ya FC.
Umwirondoro wibiti byagaragaye kuri ecran ya pre-FC scintillator (ibara rya Fiji, 2.3.0, https://imagej.net/software/fiji/).Umwanya wa magnetiki ya analytike ya dipole yasesenguwe kugirango uyobore umuvuduko wa Li3 + ion kumashanyarazi ya RFQ.Utudomo twubururu ahantu h'icyatsi duterwa nibikoresho bya scintillator bifite inenge.
Twageze ku gisekuru cya 7Li3 + ion dukoresheje lazeri yohanagura hejuru yumusozo wa lithium ukomeye, hanyuma urumuri rurerure rwa ion rufatwa kandi rwihuta hamwe na linac yabugenewe idasanzwe ya RFQ ikoresheje DPIS.Ku mbaraga za beam ya 1.4 MeV, impinga ya 7Li3 + yageze kuri FC nyuma yo gusesengura magneti yari mA 35.Ibi biremeza ko igice cyingenzi mugushira mubikorwa isoko ya neutron hamwe na kinematics inverse yashyizwe mubikorwa mubigeragezo.Muri iki gice cyimpapuro, hazaganirwaho igishushanyo mbonera cy’isoko rya neutron yoroheje, harimo umuvuduko mwinshi w’ingufu hamwe na sitasiyo ya neutron.Igishushanyo gishingiye kubisubizo byabonetse hamwe na sisitemu iriho muri laboratoire yacu.Twabibutsa ko impinga yumurongo wa ion urumuri rushobora kwiyongera mugabanya intera iri hagati ya lithium foil na RFQ linac.Umuceri.7 irerekana igitekerezo cyose cyasabwe guhuza neutron isoko yihuta.
Igishushanyo mbonera cya tekinoroji ya neutron yatanzwe kuri yihuta (yashushanijwe na Freecad, 0.19, https://www.freecadweb.org/).Uhereye iburyo ujya ibumoso: isoko ya laser ion, magnet solenoid, linac ya RFQ, guhererekanya ingufu ziciriritse (MEBT), IH linac, hamwe nicyumba cyo gukorana na neutron.Kurinda imirasire bitangwa cyane cyane mubyerekezo byimbere bitewe nuburyo bugufi bwerekanwe kumirasire ya neutron.
Nyuma ya linac ya RFQ, harateganijwe kurushaho kwihuta kwa Inter-digital H-imiterere (IH linac) linac 30.IH linacs ikoresha π-uburyo bwa drift tube imiterere kugirango itange amashanyarazi menshi murwego rwo hejuru rwumuvuduko.Ubushakashatsi bwibitekerezo bwakozwe bushingiye kuri 1D longitudinal dynamic simulation na 3D shell simulation.Ibiharuro byerekana ko 100 MHz IH linac hamwe na voltage ya drift itwara neza (munsi ya 450 kV) hamwe na rukuruzi yibanda cyane irashobora kwihutisha urumuri rwa mA 40 kuva kuri 1.4 kugeza kuri 14 MeV intera ya 1.8 m.Ikwirakwizwa ryingufu kumpera yuruhererekane rwihuta riteganijwe kuri ± 0.4 MeV, ntabwo bigira ingaruka zikomeye kumurongo wingufu za neutron zakozwe nintego yo guhindura neutron.Byongeye kandi, emissivite ya beam iri hasi bihagije kugirango yereke urumuri mumwanya muto muto kuruta uko byakenerwa kugirango imbaraga ziciriritse nubunini bwa magneti ya kane.Mu gukwirakwiza ingufu ziciriritse (MEBT) hagati ya RFQ linac na IH linac, resonator ya beamforming ikoreshwa kugirango ibungabunge imiterere.Imashini eshatu za kane zikoreshwa mugucunga ubunini bwuruhande.Ubu buryo bwo gushushanya bwakoreshejwe mubyihuta byinshi 31,32,33.Uburebure bwuzuye bwa sisitemu yose kuva inkomoko ya ion kugera mucyumba cyagenewe kugereranywa ni munsi ya m 8, zishobora gukwira mu gikamyo gisanzwe.
Intego yo guhindura neutron izashyirwaho nyuma yumurongo wihuta.Turaganira kubishushanyo mbonera bya sitasiyo dushingiye kubushakashatsi bwibanze dukoresheje ibintu bya kinematike.Intego zahinduwe zahinduwe zirimo ibikoresho bikomeye (polypropilene (C3H6) na hydride ya titanium (TiH2)) hamwe na sisitemu ya gaze.Buri ntego ifite ibyiza nibibi.Intego zikomeye zemerera kugenzura neza.Intego yoroheje, nukuri neza gahunda yumwanya wa neutron.Ariko, intego nkizo zishobora kuba zifite urwego runaka rwa reaction ya kirimbuzi idakenewe.Ku rundi ruhande, intego ya hydrogène irashobora gutanga ibidukikije bisukuye mu gukuraho umusaruro wa 7Be, umusaruro nyamukuru w’ibikorwa bya kirimbuzi.Nyamara, hydrogène ifite ubushobozi buke bwo gukumira kandi isaba intera nini yumubiri kugirango irekure ingufu zihagije.Ibi ni bibi cyane kubipimo bya TOF.Byongeye kandi, niba firime yoroheje ikoreshwa mugushiraho intego ya hydrogène, ni ngombwa kuzirikana igihombo cyatewe nimirasire ya gamma iterwa na firime yoroheje hamwe na lithium beam.
LICORNE ikoresha intego ya polypropilene kandi sisitemu igamije yazamuye ingirabuzimafatizo za hydrogène zifunze hamwe na tantalum foil.Dufashe ko urumuri ruri kuri 100 nA kuri 7Li34, sisitemu zombi zishobora kubyara kugeza kuri 107 n / s / sr.Niba dushyizeho ingufu za neutron zivamo isoko ya neutron, noneho urumuri rushobora gukoreshwa na lithium ya 7 × 10–8 C irashobora kuboneka kuri buri laser pulse.Ibi bivuze ko kurasa lazeri kabiri gusa kumasegonda bitanga 40% neutron kurusha LICORNE ishobora kubyara mumasegonda imwe hamwe nigiti gikomeza.Amazi yose arashobora kwiyongera byoroshye mukongera inshuro zishimishije za laser.Niba twibwira ko ku isoko hari sisitemu ya 1 kHz ya lazeri, impuzandengo ya neutron flux irashobora kwaguka byoroshye kugeza kuri 7 × 109 n / s / sr.
Iyo dukoresheje igipimo cyinshi cyo gusubiramo hamwe nintego za pulasitike, birakenewe kugenzura ubushyuhe bwumuriro kubigenewe kuko, nkurugero, polypropilene ifite ubushyuhe buke bwa 145–175 ° C hamwe nubushyuhe buke bwa 0.1–0.22 W / m / K.Kumurongo wa 14 MeV lithium-ion, intego ya 7 µm ya polypropilene irahagije kugirango igabanye ingufu zumuriro kugera kumyitwarire (13.098 MeV).Urebye ingaruka zose za ion zakozwe na lazeri imwe yarashwe ku ntego, ingufu za ioni ya lithium binyuze muri polypropilene zigera kuri 64 mJ / pulse.Dufashe ko ingufu zose zoherezwa muruziga rufite umurambararo wa mm 10, buri pulse ihuye n'izamuka ry'ubushyuhe bwa 18 K / pulse.Kurekura ingufu ku ntego za polypropilene bishingiye ku gitekerezo cyoroshye ko gutakaza ingufu zose bibikwa nkubushyuhe, nta mirasire cyangwa ibindi bitakaza ubushyuhe.Kubera ko kongera umubare wa pulses kumasegonda bisaba kurandura ubushyuhe, turashobora gukoresha intego kugirango twirinde gusohora ingufu kumwanya umwe23.Dufashe umwanya wa mm 10 kumurambararo ufite intego yo gusubiramo laser ya Hz 100, umuvuduko wo gusikana kaseti ya polypropilene waba 1 m / s.Igipimo cyo gusubiramo kiri hejuru birashoboka niba urumuri rwuzuye rwemewe.
Twakoze kandi ubushakashatsi ku ntego hamwe na bateri ya hydrogène, kubera ko ibiti bikomeye byo gutwara bishobora gukoreshwa bitangiza intego.Urumuri rwa neutron rushobora guhuzwa byoroshye muguhindura uburebure bwa chambre ya gaze hamwe numuvuduko wa hydrogène imbere.Icyuma cyoroshye cyane gikoreshwa mukwihutisha gutandukanya akarere ka gaze yintego na vacuum.Niyo mpamvu, birakenewe kongera ingufu zibyabaye bya lithium-ion kugirango hishyurwe igihombo cyingufu kuri file.Inteko yagenewe gusobanurwa muri raporo ya 35 yari igizwe na aluminiyumu ifite cm 3,5 z'uburebure hamwe na gaze ya H2 ya 1.5 atm.Igiti cya 16.75 MeV lithium ion yinjira muri bateri ikoresheje umuyaga ukonje wa 2.7 µm Ta foil, kandi ingufu za beam ya ion ya lithium kumpera ya bateri irihuta kugera kurwego rwo kubyitwaramo.Kugira ngo ingufu za beam ya bateri ya lithium-ion kuva kuri 14.0 MeV ikagera kuri 16.75 MeV, linac ya IH yagombaga kwongerwa na cm 30.
Hakozwe kandi imyuka ya neutron iva mu ngirabuzimafatizo ya gaze.Kubijyanye na gaze ya LICORNE yavuzwe haruguru, ibigereranyo bya GEANT436 byerekana ko neutron zerekanwa cyane zibyara imbere muri cone, nkuko bigaragara ku gishushanyo 1 muri [37].Reba 35 yerekana ingufu zingana kuva 0.7 kugeza 3.0 MeV hamwe no gufungura cone ntarengwa ya 19.5 ° ugereranije nicyerekezo cyo gukwirakwiza urumuri nyamukuru.Neutron yerekanwe cyane irashobora kugabanya cyane ubwinshi bwibikoresho byo gukingira impande nyinshi, kugabanya uburemere bwimiterere no gutanga ihinduka ryinshi mugushiraho ibikoresho byo gupima.Duhereye ku kurinda imirasire, usibye neutron, iyi ntego ya gaze isohora imirasire ya gamma 478 keV isotropically muri sisitemu yo guhuza ibice 38.Iyi ray-imirasire yakozwe nkigisubizo cya 7Be kubora na 7Li deexcitation, bibaho mugihe Li beam yibanze ikubise idirishya ryinjira Ta.Ariko, wongeyeho umubyimba wa 35 Pb / Cu silindrike, inyuma irashobora kugabanuka cyane.
Nkindi ntego, umuntu arashobora gukoresha idirishya rya plasma [39, 40], bigatuma bishoboka kugera kumuvuduko mwinshi wa hydrogène ugereranije nakarere gato k’ibisekuru bya neutron, nubwo biri munsi yintego zikomeye.
Turimo gukora iperereza kuri neutron ihinduka igamije guhitamo ingufu ziteganijwe gukwirakwizwa hamwe nubunini bwurumuri rwa lithium ion ukoresheje GEANT4.Ibigereranyo byacu byerekana gukwirakwiza imbaraga za neutron no gukwirakwiza inguni ya hydrogène intego mubitabo byavuzwe haruguru.Muri sisitemu iyo ari yo yose igamije, neutron yerekanwe cyane irashobora kubyara reaction ya kinematike iterwa na 7Li3 + igiti gikomeye kuri hydrogene ikungahaye.Kubwibyo, amasoko mashya ya neutron arashobora gushyirwa mubikorwa muguhuza tekinoroji isanzwe.
Imirasire ya laser yabyaye ubushakashatsi bwa ion beam mbere yo kwerekana byihuse.Lazeri ni desktop ya nanosekond Nd: Sisitemu YAG ifite ingufu za laser zingana na 1012 W / cm2, uburebure bwibanze bwa 1064 nm, ingufu zumwanya wa 800 mJ, hamwe nimpiswi yamara 6 ns.Ikibanza cya diameter ku ntego cyagereranijwe kuri 100 µm.Kuberako icyuma cya lithium (Alfa Aesar, 99,9% cyera) cyoroshye cyane, ibikoresho byaciwe neza bikanda mubibumbano.Ibipimo bya file 25 mm × 25 mm, uburebure bwa mm 0,6.Ibyangiritse bisa na Crater bibaho hejuru yintego iyo laser iyikubise, intego rero yimurwa na moteri ifite moteri kugirango itange igice gishya cyubuso bwintego hamwe na buri lazeri yarashwe.Kugira ngo wirinde kwiyubaka bitewe na gaze isigaye, igitutu mu cyumba cyagumishijwe munsi ya 10-4 Pa.
Ingano yambere ya plasma ya laser ni nto, kubera ko ubunini bwa laser ari 100 mkm no muri 6 ns nyuma yigihe cyayo.Ingano irashobora gufatwa nkikintu nyacyo kandi ikagurwa.Niba detector ishyizwe kure ya xm kuva hejuru yintego, noneho ibimenyetso byakiriwe byumvira isano: ion ikigezweho I, igihe cyo kugera ion t, nubugari bwa pulse τ.
Plasma yakozwe yakozwe nubushakashatsi bwa TOF hamwe na FC hamwe nisesengura ryingufu za ion (EIA) ziri hagati ya m 2,4 na m 3,85 uvuye kuntego ya laser.FC ifite suppressor grid ibogamye na -5 kV kugirango ikumire electron.EIA ifite dogere 90 ya electrostatike deflector igizwe na electrode ebyiri ya coaxial metal silindrike ifite voltage imwe ariko ihabanye na polarite, nziza hanze nibibi imbere.Kwiyongera kwa plasma kwerekeza muri deflector inyuma yumwanya hanyuma ugahindurwa numurima wamashanyarazi unyura muri silinderi.Ions zuzuza umubano E / z = eKU zimenyekana ukoresheje Secondary Electron Multiplier (SEM) (Hamamatsu R2362), aho E, z, e, K, na U arizo mbaraga za ion, leta ishinzwe, hamwe nubushakashatsi ni EIA geometrike .electron, kimwe, hamwe nibishobora gutandukana hagati ya electrode.Muguhindura voltage hejuru ya deflector, umuntu arashobora kubona ingufu nogukwirakwiza ion muri plasma.Umuvuduko ukabije wa U / 2 EIA uri hagati ya 0.2 V kugeza 800 V, ibyo bikaba bihuye ningufu za ion ziri hagati ya 4 eV na 16 keV kuri leta yishyuza.
Ikwirakwizwa ryamafaranga yishyurwa rya ion zasesenguwe mugihe cyimirasire ya lazeri zasobanuwe mu gice cyitwa "Igisekuru cya lithium yambuwe burundu" irerekanwa mu mashusho.8.
Isesengura ryikwirakwizwa rya leta ishinzwe ion.Dore ion ya none yubucucike bwigihe cyasesenguwe na EIA kandi gipima kuri m 1 uvuye kuri lithium foil ukoresheje ikigereranyo.(1) na (2).Koresha uburyo bwo gukwirakwiza imirasire ya laser byasobanuwe mu gice cyitwa "Igisekuru cya Litiyumu Yuzuye Yuzuye".Muguhuza buri cyerekezo cyubu, igipimo cya ion muri plasma cyabazwe, cyerekanwe mubishusho 3.
Inkomoko ya Laser irashobora gutanga imbaraga nyinshi-mA ion hamwe nigiciro kinini.Nyamara, gutanga ibiti biragoye cyane kubera kwanga umwanya, bityo ntibyakoreshejwe cyane.Muri gahunda gakondo, imirishyo ya ion ikurwa muri plasma hanyuma ikajyanwa kumuvuduko wibanze kumurongo wumurongo hamwe na magnesi nyinshi yibandaho kugirango ube ion beam ukurikije ubushobozi bwo gutwara bwihuta.Mu kirere cy’ingufu zo mu kirere, ibiti bitandukanya umurongo, kandi igihombo gikomeye kigaragara cyane cyane mu karere k’umuvuduko muke.Kugira ngo iki kibazo gikemuke mu iterambere ryihuta rya karubone, hashyizweho gahunda nshya yo gutanga ibiti bya DPIS41.Twakoresheje ubu buryo kugirango twihutishe urumuri rukomeye rwa lithium-ion duhereye kuri neutron nshya.
Nkuko bigaragara ku gishushanyo.4, umwanya plasma ikorerwamo kandi yagutse ikikijwe nicyuma.Umwanya ufunzwe ugera ku bwinjiriro bwa resonator ya RFQ, harimo ingano iri imbere muri coiloide.Umuvuduko wa 52 kV washyizwe kuri kontineri.Muri resonator ya RFQ, ion zikururwa nubushobozi zinyuze mu mwobo wa mm 6 wa diametre uhagarika RFQ.Imbaraga zidafite umurongo zanga umurongo kumurongo zivanwaho kuko ion zitwarwa muri plasma.Mubyongeyeho, nkuko byavuzwe haruguru, twashyizeho umurima wa solenoid dufatanije na DPIS kugirango tugenzure kandi twongere ubwinshi bwa ion muburyo bwo gukuramo.
Umuvuduko wa RFQ ugizwe na chambre ya vacuum ya silindrike nkuko bigaragara mumitini.9a.Imbere muri yo, inkoni enye z'umuringa utagira ogisijeni zishyirwa kuri quadrupole-mu buryo bumwe mu buryo buzengurutse umurongo w'igiti (Ishusho 9b).Inkoni 4 nibyumba bigize uruziga rwa RF.Umwanya wa RF uterwa na voltage ikora igihe gitandukanye na voltage hejuru yinkoni.Ions yatewe igihe kirekire hafi ya axis ifatwa kuruhande n'umurima wa quadrupole.Mugihe kimwe, isonga yinkoni irahindurwa kugirango ikore umurima w'amashanyarazi.Umwanya wa axial ugabanyijemo urumuri rwikurikiranya murukurikirane rwibiti byitwa ibiti.Buri rumuri rurimo mugihe runaka cyizunguruka cya RF (10 ns).Ibiti byegeranye bitandukanijwe ukurikije ibihe bya radio.Muri linac ya RFQ, urumuri rwa 2 µs ruva mumasoko ya laser ion ruhinduka murukurikirane rwibiti 200.Igiti noneho cyihuta kugeza ingufu zabazwe.
Kwihuta kumurongo RFQ.(a) (ibumoso) Reba hanze yicyumba cya RFQ linac.(b) (iburyo) electrode-inkoni enye mu cyumba.
Ibishushanyo mbonera byingenzi byerekana umurongo wa RFQ ni voltage yinkoni, inshuro ya resonant, radiyo ya radiyo, hamwe na electrode.Hitamo voltage ku nkoni ± 29 kV kugirango umurima wamashanyarazi uri munsi yumuriro wamashanyarazi.Hasi ya rezantike yumurongo, nini nini yibanda kumurongo hamwe nimbaraga ntoya yo kwihuta.Imirasire nini ya aperture ituma bishoboka kongera ingano yumurambararo, hanyuma, ukongera urumuri rwumuriro bitewe numwanya muto wo kwanga umwanya.Kurundi ruhande, radiyo nini ya aperture isaba imbaraga za RF nyinshi kugirango ikoreshe linac ya RFQ.Mubyongeyeho, bigarukira kubisabwa ubuziranenge bwurubuga.Hashingiwe kuri ubwo buringanire, radiyo yumurongo (100 MHz) hamwe na radiyo ya aperture (4,5 mm) byatoranijwe kugirango byihuta cyane.Guhindura byatoranijwe kugirango ugabanye igihombo kandi ugabanye kwihuta.Igishushanyo cyateguwe neza inshuro nyinshi kugirango gitange igishushanyo mbonera cya RFQ gishobora kwihuta 7Li3 + ion kuri 40 mA kuva kuri 22 keV / n kugeza kuri 204 keV / n muri m 2.Imbaraga za RF zapimwe mugihe cyubushakashatsi zari 77 kW.
Imirongo ya RFQ irashobora kwihuta ion hamwe na Q / A yihariye.Kubwibyo, iyo usesenguye igiti cyagaburiwe kugeza kumpera yihuta yumurongo, ni ngombwa kuzirikana isotopi nibindi bintu.Byongeye kandi, ion yifuzwa, yihuta igice, ariko ikamanuka mubihe byihuta hagati yihuta, irashobora guhura no gufungwa kandi irashobora kujyanwa kumpera.Imirasire idakenewe usibye injeniyeri ya 7Li3 + yitwa umwanda.Mu bushakashatsi bwacu, umwanda wa 14N6 + na 16O7 + wari uhangayikishijwe cyane, kubera ko icyuma cya lithium gifata ogisijeni na azote mu kirere.Izi ion zifite igipimo cya Q / A gishobora kwihuta hamwe na 7Li3 +.Dukoresha magnesi ya dipole kugirango dutandukanye imirire yubwiza nubwiza butandukanye bwo gusesengura ibiti nyuma ya linac ya RFQ.
Umurongo wibiti nyuma ya linac ya RFQ yagenewe kugeza 7Li3 + yihuta yuzuye muri FC nyuma ya magneti ya dipole.-400 V bias electrode ikoreshwa muguhagarika electroni ya kabiri mugikombe kugirango bapime neza umuyaga wa ion.Hamwe na optique, inzira ya ion itandukanijwe muri dipole kandi yibanda ahantu hatandukanye bitewe na Q / A.Bitewe nibintu bitandukanye nko gukwirakwiza umuvuduko no kwanga umwanya wo kwanga, urumuri kumurongo rwibanze rufite ubugari runaka.Ubwoko bushobora gutandukana gusa iyo intera iri hagati yibirindiro byubwoko bubiri bwa ion iruta ubugari bwibiti.Kugirango ubone igisubizo gishoboka gishoboka, umurongo utambitse ushyirwa hafi yikibuno, aho urumuri ruba rwibanze.Mugaragaza ecran (CsI (Tl) kuva Saint-Gobain, mm 40 × 40 mm × 3 mm) yashyizwe hagati ya PC na PC.Scintillator yakoreshejwe kugirango hamenyekane uduce duto duto duto duto twagombaga kunyuramo kugira ngo tumenye neza kandi twerekane ingano y’ibiti byemewe ku biti biremereye bya ion.Ishusho ya beam kuri scintillator yanditswe na kamera ya CCD ikoresheje idirishya.Hindura igihe cyo kwerekana idirishya kugirango utwikire ubugari bwa beam pulse.
Imibare yakoreshejwe cyangwa yasesenguwe mubyigisho byubu iraboneka kubanditsi babisabwe babisabye.
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