304L.

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Seimwe nzira yezvidzidzo zvemareactors enyukireya, jenareta rinofambiswa nenyutroni rinofambiswa nekompakiti rinoshandisa lithium-ion beam driver rinogona kunge riri munhu anovimbisa nekuti rinoburitsa mwaranzi isingadikanwi.Zvisinei, zvakanga zvakaoma kuunza danda rakasimba re lithium ions, uye kushandiswa kwezvishandiso zvakadaro kwaionekwa sezvisingabviri.Dambudziko rakanyanyisa rekusakwana kweion kuyerera rakagadziriswa nekushandisa yakananga plasma implantation scheme.Muchirongwa ichi, yakakwira-density pulsed plasma inogadzirwa nelaser ablation ye lithium metal foil inonyatso jekiseni uye inokwidziridzwa ne-high-frequency quadrupole accelerator (RFQ accelerator).Isu takawana peak beam ikozvino ye35 mA yakakwidziridzwa kusvika 1.43 MeV, inova maodha maviri ehukuru hwepamusoro pane akajairwa jekiseni uye accelerator masisitimu anogona kupa.
Kusiyana neX-rays kana zvidimbu zvakachajiwa, manyuturoni ane kudzika kukuru kwekupinda uye kudyidzana kwakasiyana nechinhu chakapfupikiswa, zvichiita kuti ive maprobes akasiyana-siyana ekudzidza maitiro emidziyo1,2,3,4,5,6,7.Kunyanya, nzira dzekuparadzira neutron dzinowanzo shandiswa kudzidza kuumbwa, chimiro, uye kushushikana kwemukati muchinhu chakapfupikiswa uye inogona kupa ruzivo rwakadzama pamusoro pemakomisheni ekutsvaga musimbi alloys ayo akaoma kuona uchishandisa X-ray spectroscopy8.Iyi nzira inoonekwa sechishandiso chine simba musainzi yekutanga uye inoshandiswa nevagadziri vesimbi nezvimwe zvinhu.Munguva pfupi yapfuura, neutron diffraction yakashandiswa kuona kusarira kunetseka mumichina yemagetsi senge njanji uye zvikamu zvendege9,10,11,12.Neutrons anoshandiswawo mumatsime emafuta negasi nekuti anotorwa zviri nyore neproton-rich materials13.Nzira dzakafanana dzinoshandiswawo mu civil engineering.Isiri-inoparadza neutron kuyedza chishandiso chinoshanda chekuona zvikanganiso zvakavanzwa muzvivakwa, tunnel nemabhiriji.Kushandiswa kwemanyutroni matanda kunoshandiswa zvakanyanya mukutsvagisa kwesainzi uye indasitiri, mazhinji ayo akave akagadzirwa kare achishandisa nuclear reactor.
Zvakadaro, nekubvumirana kwepasi rose pamusoro pekusawanda kwenyukireya, kuvaka mareactor madiki ezvinangwa zvekutsvaga kuri kuramba kuchioma.Uyezve, tsaona yenguva pfupi yapfuura yeFukushima yakaita kuti kuvaka mareactors enyukireya kuve kunogamuchirika munzanga.Maererano nemaitiro aya, kudiwa kwemanyutroni masosi kune accelerator kuri kukura2.Seimwe nzira kune mareactor enyukireya, akati wandei makuru accelerator-splitting neutron masosi ave kutoshanda14,15.Nekudaro, kuti unyatso shandisa zvivakwa zvenyutroni matanda, zvinodikanwa kuwedzera mashandisirwo emakompakiti masosi kune accelerators, 16 angave ari emaindasitiri nemayunivhesiti ekutsvagisa masangano.Accelerator neutron masosi akawedzera hunyanzvi uye mabasa mukuwedzera kushanda sechinotsiva chenyukireya reactor14.Semuenzaniso, jenareta inofambiswa nelinac inogona nyore kugadzira rwizi rwemanyutroni nekushandisa danda rekutyaira.Kana aburitswa, manyuturoni anonetsa kudzora uye kuyerwa kwemwaranzi kunonetsa kuongorora nekuda kweruzha rwunogadzirwa nemanyutroni ekumashure.Pulsed neutrons inodzorwa neaccelerator inodzivirira dambudziko iri.Mapurojekiti akati wandei anoenderana neproton accelerator tekinoroji akakurudzirwa kutenderera pasirese17,18,19.Zvinoitwa 7Li(p, n)7Be na 9Be(p, n)9B zvinonyanya kushandiswa mumajenareta anotyairwa neproton compact neutron nekuti maendothermic reactions20.Kuwedzera mwaranzi uye tsvina yeradioactive inogona kudzikiswa kana simba rakasarudzwa kufadza proton danda riri pamusoro pechikumbaridzo kukosha.Zvisineyi, huremu hwenyukiresi inonangwa hukuru kupfuura hwemaproton, uye manyuturoni anozobuda anopararira kumativi ese.Kwakadaro pedyo neisotropic emission yeneutron flux inodzivirira kufambiswa kwakanaka kwemanyutroni kuenda kuchinhu chinodzidzwa.Mukuwedzera, kuti uwane dhigirii inodiwa yemanyutroni panzvimbo yechinhu, zvakakosha kuti uwedzere zvakanyanya nhamba yeprotoni inofamba uye simba ravo.Nekuda kweizvozvo, madosi makuru emaranzi egamma nemanyuturoni anopararira nemakona mahombe, zvichiparadza mukana we endothermic reactions.Yakajairika accelerator-inotyairwa compact proton-yakavakirwa neutron jenareta ine yakasimba mwaranzi inodzivirira uye ndiyo yakawanda chikamu chehurongwa.Iko kudikanwa kwekuwedzera simba rekutyaira proton kazhinji kunoda kuwedzera kwekuwedzera muhukuru hwenzvimbo yekumhanyisa.
Kukunda zvikanganiso zvakajairika zvezvakajairwa compact neutron masosi pane accelerators, inversion-kinematic reaction scheme yakatsanangurwa21.Muchirongwa ichi, inorema lithium-ion beam inoshandiswa segwara rekutungamira panzvimbo yeproton danda, inonangana nehydrogen-rich zvinhu zvakaita sehydrocarbon mapurasitiki, hydrides, hydrogen gasi, kana hydrogen plasma.Dzimwe nzira dzakarangarirwa, dzakadai sebheryllium ion-driven matanda, zvisinei, beryllium chinhu chine muchetura chinoda kunyatsotarisirwa pakubata.Nokudaro, lithiamu danda ndiyo inonyanya kukodzera kune inversion-kinematic reaction schemes.Sezvo simba re lithium nuclei rakakura kupfuura iro remaproton, pakati pehuwandu hwekudhumhana kwenyukireya inogara ichienda mberi, uye manyuturoni anoburitswa mberi.Ichi chimiro chinobvisa zvakanyanya zvisingadiwe gamma rays uye yakakwirira kona neutron emissions22.Kuenzanisa kweyakajairika kesi yeinjini yeproton uye inverse kinematics mamiriro inoratidzwa muMufananidzo 1.
Mufananidzo wemakona ekugadzira neutron eproton uye lithium matanda (akadhonzwa neAdobe Illustrator CS5, 15.1.0, https://www.adobe.com/products/illustrator.html).(a) Maneutron anogona kudzingwa chero munzira semugumisiro wekuita nekuda kwekuti maproton anofamba anorova maatomu anorema eiyo lithium target.(b) Zvakasiyana, kana mutyairi welithium-ion achibhomba chinangwa chehydrogen-rich, manyuturoni anogadzirwa mukoni yakamanikana munzira yekumberi nekuda kwekukwira kwenzvimbo yepakati yehurongwa.
Zvisineyi, majenareta mashoma ekinematic neutron aripo nekuda kwekuomerwa kwekugadzira kuyerera kunodiwa kwemaion anorema ane chaji yakakura kana ichienzaniswa nemaproton.Zvese izvi zvinomera zvinoshandisa zvisina kunaka sputter ion masosi pamwe chete ne tandem electrostatic accelerators.Mamwe marudzi emaion masosi akakurudzirwa kuti awedzere kushanda kwebeam acceleration26.Chero zvazvingaitika, iyo iripo lithium-ion beam ikozvino inogumira ku100 µA.Yakarongedzerwa kushandisa 1 mA yeLi3 + 27, asi iyi ion beam ikozvino haina kusimbiswa neiyi nzira.Panyaya yekusimba, lithium beam accelerator haigoni kukwikwidza neproton beam accelerators ayo peak proton ikozvino inodarika 10 mA28.
Kushandisa jenareta rinoshanda neutron jenareta rinobva parithium-ion beam, zvinobatsira kugadzira yakakwira-simba isina maion.Iwo maion anokwidziridzwa uye anotungamirwa nemagetsi emagetsi, uye yakakwira yekuchaja nhanho inokonzeresa kukurumidza kukurumidza.Vatyairi veLi-ion beam vanoda Li3+ peak currents inodarika gumi mA.
Mubasa iri, isu tinoratidza kukurumidza kweLi3 + matanda ane peak currents anosvika 35 mA, iyo inofananidzwa neyepamberi proton accelerators.Iyo yekutanga lithium ion beam yakagadzirwa uchishandisa laser ablation uye Direct Plasma Implantation Scheme (DPIS) yakatanga kugadzirwa kuti ikurumidze C6+.Yakagadzirwa-yakagadzirirwa redhiyo frequency quadrupole linac (RFQ linac) yakagadzirwa uchishandisa mana-tsvimbo resonant chimiro.Isu takaona kuti danda rinomhanyisa rine yakaverengerwa kuchena kwebeam simba.Kamwe danda reLi3 + rakanyatso kutorwa uye rinokurumidza neredhiyo frequency (RF) accelerator, chikamu chinotevera chelinac (accelerator) chinoshandiswa kupa simba rinodiwa kuti rive neutron flux yakasimba kubva pane chinangwa.
Iko kukwidziridzwa kweiyo yakanyanya kuita ion tekinoroji yakasimbiswa.Iro basa rasara rekuona nyowani inoshanda kwazvo compact neutron jenareta kugadzira huwandu hukuru hwakabviswa zvachose lithium ion uye kugadzira cluster chimiro chinosanganisira nhevedzano yeion pulses yakawiriraniswa neRF kutenderera mune accelerator.Mhedzisiro yezviyedzo zvakagadzirirwa kuzadzisa chinangwa ichi zvinotsanangurwa muzvikamu zvitatu zvinotevera: (1) chizvarwa cheiyo isina zvachose lithium-ion danda, (2) kusimudzira kwebheti uchishandisa yakanyatsogadzirwa RFQ linac, uye (3) kukurumidza kuongororwa. yedanda kutarisa zvirimo.PaBrookhaven National Laboratory (BNL), isu takavaka iyo yekuyedza setup inoratidzwa muFigure 2.
Mhedziso yezviyedzo zvekumisikidza kuongororwa kwe lithium matanda (inoratidzwa neInkscape, 1.0.2, https://inkscape.org/).Kubva kurudyi kuenda kuruboshwe, laser-ablative plasma inogadzirwa mukamuri yekudyidzana yelaser-target uye inounzwa kune RFQ linac.Pakupinda muRFQ accelerator, maion anoparadzaniswa kubva kuplasma uye anoiswa muRFQ accelerator kuburikidza nemunda wemagetsi wakangoerekana wagadzirwa ne 52 kV voltage musiyano pakati pe electrode yekubvisa uye RFQ electrode munharaunda ye drift.Ioni dzakabviswa dzinokwidziridzwa kubva pa22 keV/n kusvika 204 keV/n uchishandisa 2 metres kureba RFQ electrodes.Azvino transformer (CT) yakaiswa pakubuda kweRFQ linac inopa kusingaparadzi kuyerwa kweion beam ikozvino.Danda rinotariswa nemagineti matatu equadrupole uye rinonangidzirwa kune dipole magineti, iyo inoparadzanisa uye inotungamira Li3 + danda mu detector.Seri kwepakatsemuka, chinodzoreredzwa chepurasitiki scintillator uye kapu yeFaraday (FC) ine bias inosvika -400 V inoshandiswa kuona danda riri kukurumidza.
Kuti ugadzire zvizere ionized lithium ions (Li3+), zvinodikanwa kugadzira plasma ine tembiricha iri pamusoro peyechitatu ionization simba (122.4 eV).Takaedza kushandisa laser ablation kugadzira high-tembiricha plasma.Iyi mhando yelaser ion sosi haiwanzo kushandiswa kugadzira lithium ion matanda nekuti lithium simbi inoshanda uye inoda yakakosha kubata.Isu takagadzira chinangwa chekurodha sisitimu yekudzikisa hunyoro uye kusvibiswa kwemhepo pakuisa lithium foil muvacuum laser interaction chamber.Zvose zvakagadzirirwa zvezvinhu zvakaitwa munzvimbo inodzorwa yeargon yakaoma.Mushure mekunge iyo lithium foil yakaiswa mukamuri ye laser target, iyo foil yakavhenekerwa ne pulsed Nd: YAG laser radiation pane simba re800 mJ per pulse.Pakutarisa pane chinangwa, iyo laser simba density inofungidzirwa kuita 1012 W/cm2.Plasma inogadzirwa kana pulsed laser inoparadza chinangwa muvacuum.Munguva yese ye6 ns laser pulse, plasma inoramba ichipisa, kunyanya nekuda kweiyo reverse bremsstrahlung process.Sezvo pasina kuvharirwa munda wekunze unoshandiswa panguva yekudziya chikamu, iyo plasma inotanga kuwedzera muzvikamu zvitatu.Apo plasma inotanga kuwedzera pamusoro pechinangwa chepamusoro, pakati pehuwandu hwe plasma inowana velocity perpendicular kune chinangwa chepamusoro nesimba re 600 eV / n.Mushure mekupisa, plasma inoramba ichifamba munzira yeaxial kubva kune chinangwa, ichiwedzera isotropically.
Sezvinoratidzwa muMufananidzo 2, iyo ablation plasma inowedzera kuva vacuum vhoriyamu yakakomberedzwa nemudziyo wesimbi une mukana wakafanana newakatariswa.Nekudaro, iyo plasma inodonha kuburikidza nemunda-isina dunhu rakananga kuRFQ accelerator.Axial magnetic field inoshandiswa pakati pelaser irradiation chamber neRFQ linac nenzira yeronda resolenoid coil rakatenderedza vacuum room.Iyo magnetic field ye solenoid inodzvinyirira kuwedzera kweradial ye plasma inodonha kuitira kuchengetedza yakakwira plasma density panguva yekuendesa kune iyo RFQ aperture.Kune rimwe divi, iyo plasma inoramba ichikura munzira yeaxial panguva yekudonha, ichigadzira plasma yakareba.A high voltage bias inoshandiswa kumudziyo wesimbi une plasma pamberi pechiteshi chekubuda paRFQ inlet.Iyo bias voltage yakasarudzwa kuti ipe iyo inodiwa 7Li3+ jekiseni mwero kuti ikwidze kwakaringana neRFQ linac.
Iyo inokonzeresa ablation plasma haina chete 7Li3+, asiwo lithium mune dzimwe nzvimbo dzekuchaja uye zvinhu zvinosvibisa, izvo zvinotakurwa panguva imwe chete kuenda kuRFQ linear accelerator.Pasati paitwa kukurumidza kuedza uchishandisa RFQ linac, ongororo yenguva yekubhururuka (TOF) yakaitwa kuti iongorore kuumbwa uye kugoverwa kwesimba kwemaion muplasma.Iyo yakadzama yekuongorora setup uye yakacherechedzwa mamiriro-ye-charge kugoverwa kunotsanangurwa muchikamu cheNzira.Kuongorora kwakaratidza kuti 7Li3 + ions ndiyo yaiva mazamu makuru, anoverengera anenge 54% yezvikamu zvose, sezvakaratidzwa mumufananidzo 3. Maererano nekuongorora, 7Li3 + ion ikozvino pane ion beam output point inofungidzirwa pa 1.87 mA.Munguva yekumhanyisa bvunzo, 79 mT solenoid munda inoiswa kune iri kuwedzera plasma.Nekuda kweizvozvo, iyo 7Li3 + ikozvino yakatorwa kubva muplasma uye yakaonekwa pane detector yakawedzera nechikamu che30.
Zvidimbu zveion mune laser-yakagadzirwa plasma inowanikwa nenguva-yekubhururuka kuongororwa.Iyo 7Li1+ uye 7Li2+ ion inogadzira 5% uye 25% yeion danda, zvichiteerana.Chikamu chakaonekwa che6Li particles chinobvumirana nehupenyu hwemasikirwo e6Li (7.6%) muchinangwa che lithium foil mukati mekukanganisa kwekuedza.Kusvibiswa kweokisijeni zvishoma (6.2%) kwakaonekwa, kunyanya O1 + (2.1%) uye O2 + (1.5%), iyo inogona kunge yakakonzerwa nekusvibiswa kwepamusoro pechinangwa che lithium foil.
Sezvambotaurwa, iyo lithium plasma inonyura munzvimbo isina munda isati yapinda muRFQ linac.Iko kupinza kweRFQ linac ine 6 mm dhayamita gomba mumudziyo wesimbi, uye bias voltage i52 kV.Kunyange zvazvo RFQ electrode voltage ichichinja nekukasika ±29 kV pa100 MHz, voltage inokonzera axial kukurumidza nekuti RFQ accelerator maelectrodes ane avhareji yekugona zero.Nekuda kwesimba rakasimba remagetsi rakagadzirwa muchikamu che10 mm pakati pekuvhura uye kumucheto kweRFQ electrode, maion eplasma akanaka chete anotorwa kubva muplasma pane aperture.Muchinyakare maion ekuunza masisitimu, maion anopatsanurwa kubva kuplasma nendima yemagetsi pachinhambwe chakati wandei pamberi peRFQ accelerator uye yozonangana muRFQ aperture nedanda rinotarisa chinhu.Nekudaro, kune yakaomesesa inorema ion matanda anodiwa kune yakanyanya neutron sosi, asiri-mutsara anosemesa masimba nekuda kwenzvimbo yekuchaja mhedzisiro anogona kutungamirira kune yakakura kurasikirwa kwazvino muiyo ion yekufambisa system, kudzikamisa iyo yepamusoro ikozvino inogona kukurumidza.MuDPIS yedu, maion akakwirira anotakurwa seplasma inodonha yakananga kunzvimbo yekubuda yeRFQ aperture, saka hapana kurasikirwa kweion beam nekuda kwekuchaja kwenzvimbo.Munguva yekuratidzira uku, DPIS yakashandiswa kune lithium-ion danda kekutanga.
Iyo RFQ chimiro chakagadzirirwa kutarisa uye kumhanyisa yakaderera simba yakakwira ikozvino ion matanda uye yave chiyero chekutanga kukwirisa.Isu takashandisa RFQ kumhanyisa 7Li3+ ions kubva pakuisa simba re22 keV/n kusvika 204 keV/n.Kunyange zvazvo lithium nezvimwe zvikamu zvine mutero wakaderera mu plasma zvakabviswawo kubva mu plasma uye injected muRFQ aperture, RFQ linac inongowedzera ions necharge-to-mass ratio (Q / A) pedyo ne7Li3 +.
Pamusoro pemuonde.Mufananidzo 4 unoratidza masaisai akaonekwa neazvino transformer (CT) pakubuda kweRFQ linac uye Faraday cup (FC) mushure mekuongorora magineti, sezvakaratidzwa mufig.2. Nguva yekuchinja pakati pezviratidzo inogona kududzirwa semutsauko munguva yekubhururuka panzvimbo ye detector.Iyo peak ion ikozvino yakayerwa paCT yaive 43 mA.Muchinzvimbo cheRT, danda rakanyoreswa rinogona kunge riine kwete chete ions inomhanyisa kune yakaverengerwa simba, asiwo ions kunze kwe7Li3+, iyo isina kukurumidza kukurumidza.Nekudaro, kufanana kweiyo ion ikozvino mafomu anowanikwa nenzira yeQD nePC inoratidza kuti iyo ion ikozvino inonyanya kuve nekukasira 7Li3+, uye kuderera kweiyo yepamusoro kukosha kweiyo ikozvino paPC kunokonzerwa nekurasikirwa kwedanda panguva yekuchinjisa ion pakati peQD uye. PC.Kurasikirwa Izvi zvakare zvinosimbiswa ne envelopu simulation.Kunyatso kuyera iyo 7Li3+ danda razvino, danda rinoongororwa ne dipole magineti sekutsanangurwa kwazvino muchikamu chinotevera.
Oscillograms yedanda rinokurumidza rakanyorwa mu detector nzvimbo CT (black curve) uye FC (red curve).Izvi zviyero zvinokonzerwa nekuonekwa kwelaser radiation nephotodetector panguva yekugadzirwa kwelaser plasma.Iyo dema curve inoratidza waveform yakayerwa paCT yakabatana neRFQ linac kubuda.Nekuda kwekuswedera kwayo kune RFQ linac, detector inotora 100 MHz RF ruzha, saka 98 MHz low pass FFT sefa yakashandiswa kubvisa 100 MHz resonant RF siginecha yakaiswa pamusoro pechiratidzo chekuonekwa.Iyo dzvuku curve inoratidza waveform paFC mushure meyekuongorora magineti inotungamira iyo 7Li3+ ion danda.Mune iyi magnetic field, kunze kwe7Li3+, N6+ uye O7+ inogona kutakurwa.
Iyo ion danda mushure meRFQ linac inotariswa nenhevedzano yeatatu quadrupole anotarisisa magineti obva aongororwa nemagineti edipole kuti abvise kusvibiswa muion beam.Iyo magnetic field ye0.268 T inotungamira 7Li3+ matanda muFC.Iyo yekuona waveform yeiyi magnetic field inoratidzwa seye red curve muFigure 4. The peak beam current inosvika 35 mA, iyo inodarika ka100 yakakwira kupfuura yakajairika Li3+ danda inogadzirwa mune iripo yakajairika electrostatic accelerators.Iyo beam pulse wide i2.0 µs pahupamhi hwakazara pahafu yepamusoro.Kuonekwa kwe7Li3+ danda rine dipole magineti kunoratidza budiriro bunching uye bhiza kukurumidza.Ion beam ikozvino yakaonekwa ne FC painoongorora magnetic field ye dipole inoratidzwa muFig. 5. Peak imwe yakachena yakaonekwa, yakaparadzaniswa zvakanaka kubva kune mamwe mapeji.Sezvo maion ese akamhanyisa kusimba rekugadzira neRFQ linac aine kumhanya kwakafanana, maion matanda ane Q/A yakafanana anonetsa kupatsanurwa ne dipole magnetic fields.Naizvozvo, hatigone kusiyanisa 7Li3+ kubva kuN6+ kana O7+.Nekudaro, huwandu hwehutsvina hunogona kufungidzirwa kubva kune dzakavakidzana nechaji nyika.Semuenzaniso, N7+ neN5+ zvinogona kupatsanurwa zviri nyore, nepo N6+ inogona kunge iri chikamu chekusachena uye inotarisirwa kunge iripo muhuwandu hwakafanana neN7+ neN5+.Iyo inofungidzirwa kusvibiswa mwero inenge 2%.
Beam component spectra inowanikwa nekuongorora dipole magnetic field.Iyo yepamusoro pa 0.268 T inoenderana ne7Li3+ uye N6+.Iyo peak hupamhi inoenderana nehukuru hwedanda pane chakatsemurwa.Pasinei nepamusoro pepamusoro, 7Li3+ inoparadzanisa zvakanaka kubva ku6Li3+, O6+, uye N5+, asi inoparadzanisa zvisina kunaka kubva kuO7+ neN6+.
Panzvimbo yeFC, iyo danda profile yakasimbiswa ne-plug-in scintillator uye yakanyorwa nekamera yakakurumidza yedhijitari sezvakaratidzwa mumufananidzo 6. Iyo 7Li3 + pulsed beam ine ikozvino ye35 mA inoratidzwa kuti inokurumidza kusvika kune yakaverengwa RFQ. simba re204 keV / n, rinoenderana ne1.4 MeV, uye rinotumirwa kune FC detector.
Beam mbiri yakacherechedzwa pane pre-FC scintillator skrini (yakavezwa neFiji, 2.3.0, https://imagej.net/software/fiji/).Iyo magnetic field yeanalytical dipole magineti yakagadziridzwa kutungamira kukwidziridzwa kweLi3 + ion danda kune dhizaini simba RFQ.Iwo mavara ebhuruu munzvimbo yakasvibira anokonzerwa neyakaremara scintillator zvinhu.
Isu takawana chizvarwa che7Li3+ ions nelaser ablation pamusoro peiyo yakasimba lithium foil, uye yakakwira ikozvino ion beam yakatorwa uye yakakwidziridzwa neyakagadzirwa RFQ linac uchishandisa DPIS.Pane danda simba re1.4 MeV, iyo yepamusoro ye7Li3+ yakasvika paFC mushure mekuongororwa kwemagineti yaive 35 mA.Izvi zvinosimbisa kuti chikamu chakakosha chekushandiswa kweiyo neutron sosi ine inverse kinematics yakaitwa mukuyedza.Muchikamu chino chebepa, dhizaini yese yekombuta neutron sosi ichakurukurwa, kusanganisira yakakwirira simba accelerators uye neutron target station.Iyo dhizaini yakavakirwa pane zvakawanikwa nemasystem aripo murabhoritari yedu.Izvo zvinofanirwa kucherechedzwa kuti iyo peak ikozvino yeion beam inogona kuwedzera kuwedzera nekupfupisa kureba pakati pelithium foil neRFQ linac.Mupunga.7 inoratidza iyo pfungwa yese yeyakatsanangurwa compact neutron sosi pane accelerator.
Mafungiro dhizaini yeyakatsanangurwa compact neutron sosi pane accelerator (yakadhonzwa neFreecad, 0.19, https://www.freecadweb.org/).Kubva kurudyi kuenda kuruboshwe: laser ion sosi, solenoid magineti, RFQ linac, yepakati simba danda kufambisa (MEBT), IH linac, uye yekudyidzana kamuri yekugadzira neutron.Kudzivirirwa kwemwaranzi kunopihwa zvakanyanya munzira yekuenda kumberi nekuda kwechimiro chakanangidzirwa chakanangidzirwa ematanda akagadzirwa neutron.
Mushure meRFQ linac, imwezve kukurumidza kweInter-digital H-structure (IH linac)30 linac inorongwa.IH linacs inoshandisa π-mode drift chubhu chimiro kuti ipe yakakwirira yemagetsi munda magradients pamusoro peimwe nhanho yekumhanya.Chidzidzo chepfungwa chakaitwa zvichibva pa1D longitudinal dynamics simulation uye 3D shell simulation.Kuverenga kunoratidza kuti 100 MHz IH linac ine inonzwisisika drift chubhu voltage (isingasviki 450 kV) uye yakasimba inotarisa magineti inogona kumhanyisa 40 mA danda kubva 1.4 kusvika 14 MeV pachinhambwe che 1.8 m.Kugoverwa kwesimba pakupera kweketani yeaccelerator inofungidzirwa pa ± 0.4 MeV, iyo isinganyanyi kukanganisa simba remagetsi remanyutroni anogadzirwa neiyo neutron shanduko chinangwa.Uye zvakare, iyo simbi emissivity yakadzikira zvakakwana kuti itarise danda mune diki danda nzvimbo pane yaiwanzo kudiwa kune epakati simba uye saizi quadrupole magineti.Mune yepakati simba danda (MEBT) kutapurirana pakati peRFQ linac neIH linac, iyo beamforming resonator inoshandiswa kuchengetedza iyo beamforming chimiro.Magineti matatu equadrupole anoshandiswa kudzora saizi yedanda redivi.Iri zano rekugadzira rakashandiswa mune akawanda accelerator31,32,33.Hurefu hwakazara hwehurongwa hwese kubva kune ion sosi kuenda kukamuri yekunangwa inofungidzirwa kuve isingasviki 8 m, iyo inogona kukwana mune yakajairwa semi-trailer rori.
Iyo neutron inoshandura tarisiro ichaiswa zvakananga mushure memutsara wekumhanyisa.Isu tinokurukura zvakanangwa chiteshi dhizaini zvichibva pane zvakapfuura zvidzidzo tichishandisa inverse kinematic scenarios23.Zvinoshumwa kutendeuka zvinangwa zvinosanganisira zvinhu zvakasimba (polypropylene (C3H6) uye titanium hydride (TiH2)) uye gaseous target systems.Chinangwa chega chega chine zvakanakira nekuipira.Zvinangwa zvakasimba zvinobvumira kudzora ukobvu chaiko.Iko kutetepa kwechinangwa, ndiko kunowedzera kwakaringana kurongeka kwenzvimbo yekugadzira neutron.Zvisinei, nharidzano dzakadaro dzingave dzichine mwero wakati wokusada kwenyukireya uye mwaranzi.Kune rimwe divi, chinangwa chehydrogen chinogona kupa nharaunda yakachena nekubvisa kugadzirwa kwe7Be, chigadzirwa chikuru chekuita kwenyukireya.Nekudaro, haidhirojeni ine husina kusimba chipingamupinyi kugona uye inoda chinhambwe chikuru chemuviri kuti iburitse simba rakakwana.Izvi zvinokanganisa zvishoma kune zviyero zveTOF.Mukuwedzera, kana firimu yakaonda inoshandiswa kuvhara chinangwa chehydrogen, zvakakosha kufunga nezvekurasikirwa kwesimba kwegamma rays inogadzirwa nefirimu yakaonda uye chiitiko chinonzi lithium beam.
LICORNE inoshandisa polypropylene tarisiro uye yakanangwa system yakakwidziridzwa kuita hydrogen maseru akavharwa netantalum foil.Tichifunga danda razvino re100 nA ye7Li34, ese ari maviri masystem anogona kuburitsa kusvika 107 n/s/sr.Kana tikashandisa iyi inonzi neutron goho rekushandura kune yedu yakarongwa neutron sosi, ipapo lithium-inotyairwa danda re7 × 10–8 C inogona kuwanikwa yega yega laser pulse.Izvi zvinoreva kuti kupfura laser kaviri pasekondi kunoburitsa makumi mana muzana emamwe manyutroni kupfuura LICORNE inogona kuburitsa musekondi imwe ine danda rinoenderera.Iyo yakazara flux inogona kuwedzerwa nyore nyore nekuwedzera iyo excitation frequency ye laser.Kana tikafungidzira kuti pane 1 kHz laser system pamusika, avhareji neutron flux inogona kukwidziridzwa nyore kusvika pa7 × 109 n/s/sr.
Patinoshandisa maitiro ekudzokorora kwepamusoro ane zvinangwa zvepurasitiki, zvakakosha kudzora chizvarwa chekupisa pane zvinangwa nokuti, semuenzaniso, polypropylene ine nzvimbo yakaderera yekunyunguduka ye145-175 ° C uye yakaderera yekushisa conductivity ye 0.1-0.22 W / m/K.Kune 14 MeV lithium-ion danda, 7 µm gobvu polypropylene tarisiro inokwana kudzikisa danda simba kune reaction pachikumbaridzo (13.098 MeV).Tichifunga nezve mhedzisiro yeion inogadzirwa neimwe laser kupfura pane chinangwa, simba rekuburitswa kwe lithium ions kuburikidza ne polypropylene inofungidzirwa pa64 mJ / pulse.Tichifunga kuti simba rose rinotamirwa mudenderedzwa rine dhayamita ye10 mm, kuputika kwega kwega kunoenderana nekukwira kwekushisa kweanenge 18 K / pulse.Kuburitswa kwesimba pazvinangwa zvepolypropylene kunobva pane fungidziro yakapusa yekuti kurasikirwa kwesimba kwese kunochengetwa sekupisa, pasina mwaranzi kana kumwe kurasikirwa kwekupisa.Sezvo kuwedzera huwandu hwemapulses pasekondi kunoda kubviswa kwekupisa kwekuvaka, isu tinogona kushandisa mitsetse tarisiro kudzivirira kuburitswa kwesimba pane imwechete point23.Tichitora 10 mm danda nzvimbo pane chinangwa nelaser repetition rate ye100 Hz, kumhanya kwekutarisa kwepolypropylene tepi kungave 1 m/s.Kudzokorodza kwepamusoro kunokwanisika kana kupindirana kwebeam kuchibvumidzwa.
Isu takaongorora zvakare tarisiro nemabhatiri ehydrogen, nekuti matanda akasimba ekutyaira anogona kushandiswa pasina kukuvadza chinangwa.Iyo neutron danda inogona kugadziridzwa zviri nyore nekushandura kureba kwekamuri yegesi uye hydrogen pressure mukati.Mapepa esimbi akatetepa anowanzo shandiswa mune accelerator kuparadzanisa gasi dunhu rechinangwa kubva pavacuum.Naizvozvo, zvinodikanwa kuwedzera simba rechiitiko lithium-ion danda kuitira kutsiva kurasikirwa kwesimba pane foil.Musangano wakanangwa wakatsanangurwa mushumo 35 waive nearuminiyamu mudziyo wakareba 3.5 cm neH2 gasi pressure ye1.5 atm.Iyo 16.75 MeV lithium ion beam inopinda mubhatiri kuburikidza nemhepo-yakatonhorera 2.7 µm Ta foil, uye simba re lithium ion beam pamagumo ebhatiri rinodzikiswa kusvika pakuita chikumbaridzo.Kuti uwedzere simba remabhatiri e-lithium-ion kubva pa14.0 MeV kusvika pa16.75 MeV, IH linac yaifanira kurebeswa neanenge 30 cm.
Kuburitswa kwemanyutroni kubva kune gasi cell targets kwakadzidzwawo.Kune yambotaurwa LICORNE gasi tarisiro, GEANT436 simulations inoratidza kuti manyuturoni anotariswa zvakanyanya anogadzirwa mukati mekoni, sezvakaratidzwa mumufananidzo 1 mu [37].Reference 35 inoratidza huwandu hwesimba kubva pa0.7 kusvika 3.0 MeV ine yakanyanya kuvhurwa kwekoni ye19.5 ° inoenderana negwara rekuparadzira danda guru.Manyuturoni akatarisana zvakanyanya anogona kuderedza zvakanyanya kuwanda kwezvinhu zvinodzivirira pamakona mazhinji, kuderedza huremu hwechimiro uye kupa kuchinjika kukuru mukugadzika kwemidziyo yekuyera.Kubva pakuona kwekudzivirira kwemwaranzi, kuwedzera kune manyutroni, iyi gasi chinangwa chinoburitsa 478 keV gamma rays isotropically mu centroid coordinate system38.Aya ma-γ-mwaranzi anogadzirwa semhedzisiro yekuora kwe7Be uye 7Li deexcitation, izvo zvinoitika kana yekutanga Li beam inorova hwindo rekupinza Ta.Nekudaro, nekuwedzera gobvu 35 Pb/Cu cylindrical collimator, kumashure kunogona kudzikiswa zvakanyanya.
Sezvimwe zvinotarisirwa, munhu anogona kushandisa hwindo re plasma [39, 40], iyo inoita kuti zvikwanisike kuwana chidimbu chakakwirira che hydrogen uye nzvimbo shomanana yechizvarwa chenyutroni, kunyange zvazvo yakaderera kune zvinangwa zvakasimba.
Isu tiri kuongorora neutron shanduko yakanangana nesarudzo dzekugoverwa kwesimba rinotarisirwa uye saizi yebhanhire re lithium ion beam uchishandisa GEANT4.Mamienzaniso edu anoratidza kugoverwa kwakafanana kwesimba reneutron uye kugoverwa kweangular kwezvinangwa zvehydrogen mumabhuku ari pamusoro.Mune chero inotarirwa system, manyutroni akatarisana zvakanyanya anogona kugadzirwa neinverse kinematic reaction inotungamirwa neakasimba 7Li3+ danda pane hydrogen-rich target.Naizvozvo, masosi matsva e-neutron anogona kuitwa nekubatanidza matekinoroji agara aripo.
Iyo laser irradiation mamiriro akaburitsa ion beam chizvarwa kuyedza isati yakurumidza kuratidzira.Iyo laser idesktop nanosecond Nd: YAG system ine laser simba density ye1012 W/cm2, yakakosha wavelength ye1064 nm, nzvimbo simba re800 mJ, uye pulse nguva ye6 ns.Iyo dhayamita yenzvimbo pachinangwa inofungidzirwa pa100 µm.Nekuti lithium simbi (Alfa Aesar, 99.9% yakachena) yakapfava, iyo yakanyatsochekwa zvinhu inotsikirirwa muforoma.Foil zviyero 25 mm × 25 mm, ukobvu 0.6 mm.Kukuvadzwa kwakafanana neCrater kunoitika pamusoro pechinangwa kana laser yarova, saka chinonangwa chinofambiswa nepuratifomu ine mota kuti ipe chikamu chitsva chenzvimbo yechinangwa nepfuti yega yega laser.Kuti udzivise kubatanidzwazve nekuda kwegasi rakasara, kumanikidzwa mukamuri kwakachengetwa pasi pehuwandu hwe10-4 Pa.
Iyo yekutanga vhoriyamu yelaser plasma idiki, sezvo saizi yelaser spot iri 100 μm uye mukati me6 ns mushure mechizvarwa chayo.Iyo vhoriyamu inogona kutorwa sechinhu chaicho uye kuwedzera.Kana iyo detector ichiiswa chinhambwe xm kubva panzvimbo yakatarwa, ipapo chiratidzo chinogamuchirwa chinoteerera hukama: ion ikozvino I, ion yekusvika nguva t, uye pulse width τ.
Iyo plasma yakagadzirwa yakadzidzwa neiyo TOF nzira neFC uye ine simba ion analyzer (EIA) iri chinhambwe che 2.4 m uye 3.85 m kubva kune laser target.Iyo FC ine suppressor grid yakarerekera ne -5 kV kudzivirira maerekitironi.EIA ine 90 degree electrostatic deflector inosanganisira maviri coaxial metal cylindrical electrodes ane volti imwechete asi akapesana nepolar, akanaka kunze uye asina kunaka mukati.Iyo inowedzera plasma inonangidzirwa mukati me deflector kuseri kwe slot uye inotsauswa negetsi munda uchipfuura nemuhumburumbira.Ioni dzinogutsa hukama E/z = eKU dzinoonekwa pachishandiswa Sekondari Electron Multiplier (SEM) (Hamamatsu R2362), apo E, z, e, K, uye U ndiwo simba reion, mamiriro ekuchaja, uye kuchaja ari EIA geometric factor. .maerekitironi, zvichiteerana, uye mutsauko unokwanisa pakati pema electrode.Nekushandura voltage pa deflector, munhu anogona kuwana simba uye kubhadharisa kugoverwa kweion muplasma.Iyo yekutsvaira voltage U/2 EIA iri pakati kubva 0.2 V kusvika 800 V, iyo inoenderana neion simba muchikamu kubva 4 eV kusvika 16 keV per charge state.
Kugoverwa kwemamiriro ekuchajisa eion akaongororwa pasi pemamiriro e laser irradiation inotsanangurwa muchikamu "Chizvarwa cheyakazara yakabviswa lithium matanda" inoratidzwa muFigs.8.
Kuongororwa kwekugoverwa kwemamiriro ekutonga kweion.Heino ion yazvino density time profile yakaongororwa neEIA uye yakayerwa pa 1 m kubva pa lithium foil uchishandisa equation.(1) uye (2).Shandisa iyo laser irradiation mamiriro anotsanangurwa muchikamu che "Generation of a Completely Exfoliated Lithium Beam" chikamu.Nekubatanidza density yega yega yemazuva ano, chikamu cheion mu plasma chakaverengerwa, chinoratidzwa mumufananidzo 3.
Laser ion masosi anogona kuendesa yakanyanya kuwanda-mA ion danda ine yakakwira charge.Nekudaro, kuburitsa danda kwakaoma zvakanyanya nekuda kwekudzoreredza nzvimbo yekuchaja, saka yanga isingashandiswe zvakanyanya.Muchirongwa chechinyakare, matanda eion anotorwa kubva muplasma oendeswa kune yekutanga accelerator pamwe nemutsara wedanda une akati wandei anotarisisa magineti kuti agadzire danda reion zvinoenderana nekugona kwepikicha yeanomhanyisa.Munzvimbo yekuchaja simba matanda, matanda anosiyana asiri-mutsara, uye kurasikirwa kwakakomba kwedanda kunoonekwa, kunyanya munharaunda yeakaderera velocities.Kukunda dambudziko iri mukuvandudza kwekurapa kabhoni accelerators, chirongwa chitsva cheDPIS41 danda rekutakura chinorongwa.Isu takashandisa nzira iyi kumhanyisa ine simba lithium-ion danda kubva kune itsva neutron sosi.
Sezvinoratidzwa mufig.4, nzvimbo iyo plasma inogadzirwa uye yakawedzerwa yakakomberedzwa nemudziyo wesimbi.Nzvimbo yakavharirwa inoenda kumusuwo weRFQ resonator, kusanganisira vhoriyamu mukati meiyo solenoid coil.Vheti ye52 kV yakaiswa pamudziyo.MuRFQ resonator, maion anodhonzwa nekugona kuburikidza ne6 mm dhayamita gomba nekudzika RFQ.Izvo zvisiri-mutsara zvinosemesa masimba pamutsetse wedanda zvinobviswa sezvo ion inotakurwa mu plasma state.Mukuwedzera, sezvataurwa pamusoro apa, takaisa munda we solenoid pamwe chete neDPIS kudzora nekuwedzera kuwanda kweioni muvharo yekubvisa.
Iyo RFQ accelerator ine cylindrical vacuum chamber sezvakaratidzwa mufig.9a.Mukati mayo, tsvimbo ina dzemhangura isina okisijeni inoiswa quadrupole-symmetrically yakapoteredza danda axis (Fig. 9b).4 tsvimbo uye makamuri anoumba resonant RF dunhu.Iyo induced RF munda inogadzira inosiyana-nguva voltage padanda.Ioni dzakasimwa kureba dzakatenderedza axis dzinobatwa nechemberi nemunda we quadrupole.Panguva imwecheteyo, muromo wetsvimbo unogadziriswa kuti ugadzire axial electric field.Iyo axial munda inotsemura iyo jekiseni inoenderera danda kuita nhevedzano yedanda pulses inonzi danda.Danda rega rega riri mukati meimwe RF kutenderera nguva (10 ns).Matanda ari pedyo akapatsanurwa zvichienderana neredhiyo frequency period.Mune RFQ linac, 2 µs danda kubva kune laser ion sosi inoshandurwa kuita nhevedzano ye200 matanda.Danda rinobva rakwidziridzwa kusimba rakaverengwa.
Linear accelerator RFQ.(a) (kuruboshwe) Kuonekwa kwekunze kweRFQ linac chamber.(b) (kurudyi) ina-tsvimbo electrode mukamuri.
Iwo makuru ekugadzira ma paramita eRFQ linac ndeye voltage yetsvimbo, resonant frequency, beam hole radius, uye electrode modulation.Sarudza mhepo padanda ± 29 kV kuitira kuti magetsi ayo ari pasi pemagetsi ekuputsa chikumbaridzo.Iyo yakaderera iyo resonant frequency, yakakura iyo lateral inotarisisa simba uye idiki iyo avhareji yekumhanyisa ndima.Yakakura aperture radii inoita kuti ikwanise kuwedzera saizi yedanda uye, nekudaro, wedzera danda razvino nekuda kweiyo diki nzvimbo yekuchaja repulsion.Kune rimwe divi, yakakura aperture radii inoda rakawanda reRF simba kuti rigone RFQ linac.Mukuwedzera, inogumira nehutano hunodiwa hwesaiti.Zvichienderana nezviyero izvi, iyo resonant frequency (100 MHz) uye aperture radius (4.5 mm) zvakasarudzirwa kukwirisa-ikozvino danda kukurumidza.Iyo modulation inosarudzwa kuderedza kurasikirwa kwedanda uye kuwedzera kukurumidza kushanda.Dhizaini yakagadziridzwa kakawanda kugadzira RFQ linac dhizaini inokwanisa kumhanyisa 7Li3+ ions pa40 mA kubva pa22 keV/n kusvika 204 keV/n mukati me2 m.Simba reRF rakayerwa panguva yekuyedza raive 77 kW.
RFQ linacs inogona kumhanyisa ions neiyo Q/A siyana.Saka, kana uchiongorora danda rakadyiswa kusvika kumagumo emutsara wekusimudzira, zvakakosha kufunga nezve isotopes nezvimwe zvinhu.Pamusoro pezvo, maion anodiwa, akakwidziridzwa zvishoma, asi akaburuka pasi pemamiriro ekumhanyisa mukati meiyo accelerator, anogona achiri kusangana nekuvharirwa lateral uye anogona kutakurwa kusvika kumagumo.Mwaranzi isingadikanwi kunze kweakagadziridzwa 7Li3+ zvidimbu anonzi tsvina.Mukuedza kwedu, 14N6 + uye 16O7 + tsvina ndiyo yainyanya kunetseka, sezvo lithium metal foil inopindirana neokisijeni uye nitrogen mumhepo.Aya maion ane Q/A reshiyo inogona kukwidziridzwa ne7Li3+.Isu tinoshandisa dipole magineti kuparadzanisa matanda emhando dzakasiyana uye hunhu hwekuongororwa kwebeam mushure meRFQ linac.
Iyo danda mutsara mushure meRFQ linac yakagadzirirwa kuendesa yakawedzera kukurumidza 7Li3+ danda kuFC mushure me dipole magineti.-400 V bias electrodes inoshandiswa kudzvanya maerekitironi echipiri mumukombe kunyatsoyera iyo ion beam ikozvino.Neiyi optics, iyo ion trajectories yakapatsanurwa kuita dipoles uye yakatarisana munzvimbo dzakasiyana zvichienderana neQ/A.Nekuda kwezvinhu zvakasiyana-siyana senge kukurumidza kupararira uye nzvimbo yekuchaja repulsion, danda riri pakutarisa rine humwe hupamhi.Mhuka idzi dzinogona kupatsanurwa chete kana chinhambwe chiri pakati penzvimbo dzemaion marudzi maviri chakakura kupfuura upamhi hwedanda.Kuti uwane chigadziriso chepamusoro-soro, gomba rakachinjika rinoiswa padyo nechiuno chedanda, uko danda rinonyatso kudzika.A scintillation screen (CsI(Tl) kubva kuSaint-Gobain, 40 mm × 40 mm × 3 mm) yakaiswa pakati pekutsemuka nePC.Iyo scintillator yakashandiswa kuona kudiki kudiki kwaifanirwa kupfuura nepakati kuitira kunyatsogadziriswa uye kuratidza inogamuchirika saizi yedanda kune yakakwira ikozvino inorema ion matanda.Mufananidzo wedanda pane scintillator wakanyorwa neCCD kamera kuburikidza nehwindo rekutsvaira.Rongedza hwindo rekuratidzwa nguva kuvhara iyo yese beam pulse wide.
Datasets anoshandiswa kana kuongororwa muchidzidzo chazvino anowanikwa kubva kune vanyori vakasiyana pakukumbira zvine musoro.
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