Accelerators liniya wa particles mlandu. Monga tinthu accelerators ntchito. Chifukwa tinthu accelerators?

The accelerator wa particles mlandu - chipangizo mmene mtengo wa electrically mlandu particles atomiki kapena subatomic oyendayenda pafupifupi liwiro la. Chifukwa cha ntchito yake ndi zofunika kuchuluka kwawo mphamvu m'minda magetsi ndi kusintha njira yodutsamo - maginito.

ndi tinthu accelerators chiyani?

zipangizozi ankagwiritsa ntchito zosiyanasiyana za sayansi ndi malonda. Pakali pano, padziko lonse pali anthu oposa 30 zikwi. Pakuti sayansi ya accelerators mlandu tinthu kutumikira monga chida cha kafukufuku zofunika pa kapangidwe ka atomu, chikhalidwe cha mphamvu nyukiliya ndi katundu nyukiliya, omwe sanalembedwepo mwachibadwa. Dama transuranic ndi zinthu zina osakhazikika.

Ndi kumaliseche chubu wakhala n'zotheka kudziwa mlandu yeniyeni. Adawalamulira tinthu accelerators amagwiritsidwa ntchito pa ulimi wa radioisotopes, mu radiography mafakitale, radiotherapy, chifukwa njira yolera yotseketsa zipangizo zamoyo ndi kusanthula radiocarbon. The mayunitsi yaikulu ntchito mu kuphunzira ankachita ofunika.

The moyo wa particles mlandu pa mpumulo ndi kulemekeza accelerator ndi wocheperako kuposa particles inapita kwa imathamanga pafupi ndi kuwala kumayendera. Zimenezi zikusonyeza kuti mlingo wochepa wa okwerera nthawi. Mwachitsanzo, pa CERN wakhala akwaniritsa ndi kuwonjezeka mu moyo wa muon 0,9994c liwiro nthawi 29.

Nkhaniyi akuyang'ana zomwe mkati ndi ntchito tinthu accelerator, chitukuko, osiyanasiyana ndi zinthu zosiyanasiyana.

mfundo mathamangitsidwe

Kaya wotani accelerators mlandu tinthu inu mukudziwa, iwo onse ndi zinthu zofanana. Choyamba, iwo ayenera kupeza ma elekitironi mu nkhani ya kanema chithunzi chubu kapena ma elekitironi, mapulotoni antiparticles awo pa nkhani ya makhazikitsidwe zikuluzikulu. Komanso, iwo onse ayenera kukhala minda magetsi kuti imathandizira particles ndi mphamvu ya maginito kulamulira njira yodutsamo awo. Komanso, zingalowe m'malo mwa mlandu tinthu accelerator (10 ^-11 mamilimita Hg. V.), M. E. A wambiri osachepera mpweya yotsalira, chofunika kuonetsetsa yaitali moyo nthawi milimo. Pomaliza, makhazikitsidwe onse ayenera kupereka kalembera, ndi ochuluka ndi muyeso wa particles zolimira.

m'badwo

Ma elekitironi ndi mapulotoni, amene zambiri ntchito accelerators zimapezeka zipangizo zonse, koma choyamba iwo ayenera kusankha kwa iwo. Ma elekitironi ambiri amayambira chimodzimodzi monga mu chithunzi chubu - mu chipangizo chimene amatchedwa "mfuti". Ndi cathode (zoipa elekitirodi) mu zingalowe, umene ndi mkangano kuti boma kumene ma elekitironi kuyamba kuchokamo maatomu. particles zoipa mlandu amakopeka ndi anode (elekitirodi zabwino) ndi kudutsa kubwereketsa lapansi. Mfuti palokha ndi losavuta monga accelerator chifukwa ma elekitironi ikuyenda mchikakamizo cha munda magetsi. The voteji pakati pa cathode ndi anode, amangoona mu osiyanasiyana 50-150 kV.

Kupatula ma elekitironi mu zipangizo zonse zopezeka mapulotoni, koma limodzi purotoni phata wapangidwa maatomu wa hydrogen. Choncho, tinthu gwero kwa accelerators purotoni ndi mpweya wa hydrogen. Pankhaniyi, gasi ndi ionized ndi mapulotoni ndi ili mwa dzenje. Mu accelerators lalikulu mapulotoni nthawi zambiri aumbike mwa mawonekedwe a ayoni wa hydrogen negative. Iwo akuimilira ndi elekitironi zina ku maatomu omwe ali mankhwala a diatomic mpweya ionization. Popeza zoipa mlandu ayoni wa hydrogen mu magawo koyamba ntchito mosavuta. Kenako kudutsa ndi zojambulazo woonda, amene zimaphwanya iwo a ma elekitironi pamaso chomaliza mathamangitsidwe.

mathamangitsidwe

Monga tinthu accelerators ntchito? Mbali yaikulu ya onse a iwo kumunda magetsi. Chitsanzo losavuta - yunifolomu malo amodzi m'munda pakati pa zabwino ndi zoipa Zoyenereza magetsi wofanana ndi umene ulipo pakati pa malo a batire la magetsi. M'munda elekitironi onyamula mlandu zoipa poyera kuti mphamvu zomwe amaitsogolera angathe zabwino. Iwo Iyamba izo, ndipo ngati pali chilichonse chomwe anali kuima mu njira, liwiro ndi mphamvu zake kuwonjezeka. Ma elekitironi kulingalira lingathe zabwino pa waya kapena mu mlengalenga, ndipo adzawombana ndi maatomu kutaya mphamvu, koma ngati zili vacuo, zolimira pamene ankayandikira anode.

Kusemphana maganizo chiyambi ndi mapeto malo a imalongosola elekitironi anaŵagula mphamvu. Pamene akuyenderera kusiyana angathe 1 V ndi wofanana 1 zinthu zosiyanasiyana za Volt (EV). Ichi ndi lofanana 1,6 × 10 ^-19 joule. Mphamvu ya udzudzu zouluka zina thililiyoni kwambiri. Mu ma elekitironi kinescope ali inapita patsogolo voteji kuposa 10 kV. accelerators ambiri amene amafika mphamvu apamwamba anayeza Mega, giga ndi tera-zinthu zosiyanasiyana za volts.

mitundu

Ena mwa mitundu oyambirira accelerators tinthu monga multiplier voteji ndi jenereta van de Graaff jenereta, ntchito zonse munda magetsi kwaiye ndi zimphamvu wa ku miliyoni volts. Ndi voltages ngati mkulu ntchito mosavuta. A zina zambiri zothandiza ndi kanthu mobwerezabwereza minda magetsi ofooka opangidwa Zoyenereza otsika. Mfundo imeneyi ntchito mitundu iwiri ya accelerators zamakono - liniya ndi ozungulira (makamaka cyclotrons ndi synchrotrons). Liniya tinthu accelerators Mwachidule, anadutsa iwo kamodzi mwa ndondomeko ya minda mofulumira, pamene nthawi cyclically ambiri amasuntha panjira zozungulira mwa munda ochepa magetsi. Nthawi zonse, ndi mphamvu chomaliza cha particles chimadalira pa munda okwana kanthu, kotero kuti ambiri yaing'ono "tokhala" akuwonjezeka pamodzi kupereka zotsatira kuphatikiza umodzi waukulu.

Kapangidwe mobwerezabwereza kwa accelerator liniya kuti kupanga minda magetsi mwachibadwa kugwiritsa ntchito AC, osati DC. The particles ndithu mlandu ndi inapita patsogolo angathe mthunzi ndi kupeza kutsogolera latsopano, ngati kudali positive. Zochita za voteji ziyenera kusintha mofulumira kwambiri. Mwachitsanzo, pa mphamvu ya 1 MeV purotoni chimachititsanso pa lalitali kwambiri liwiro ndi liwiro la kuwala kwa 0,46 kudutsa 1.4 mamita wa 0.01 MS. Izi zikutanthauza kuti mu dongosolo mobwerezabwereza kwa mamita angapo yaitali, minda magetsi ayenera kusintha kolowera pa pafupipafupi osachepera 100 MHz. Liniya ndi accelerators ozungulira particles zambiri kumwazikana iwo ndi alternating munda pafupipafupi magetsi 100 MHz kwa 3000, T. E. Mu osiyanasiyana mafunde wailesi microwaves.

Yoweyula mu atomu ndi osakaniza minda zokhala magetsi ndi maginito zokhala pa kumathandiza kupeza ngodya zabwino ufulu wina ndi mnzake. Mfundo yofunika kwambiri ndi kusintha accelerator yoweyula kuti pa kufika particles munda magetsi imatsogoleredwa malinga ndi mathamangitsidwe vekitala. Izi zikhoza kuchitika pogwiritsa ntchito yoweyula ataima - kuphatikiza mafunde kuyenda mbali zosiyana danga chatsekedwa, mafunde oganiza chitoliro limba. An chimake zina mofulumira kusuntha ma elekitironi amene velocities akuyandikira kuwala kumayendera, yoweyula woyendayenda.

autophasing

Zimakhudzanso zofunika a mathamangitsidwe mu minda alternating magetsi ndi "gawo bata". Mu umodzi oscillation mkombero alternating munda umadutsa ziro ku mtengo pazipita ku ziro, izo amachepetsa yochepa ndipo kukudza kuti ziro. Choncho, chitadutsa kawiri kudzera phindu lofunika mathamangitsidwe. Ngati tinthu amene mathamangidwe ukuwonjezeka, akubwera molawirira kwambiri, izo sizigwira ntchito m'munda wa mphamvu zokwanira, ndi Kankhani adzakhala ofooka. Akafika m'dera lotsatira, mayeso mochedwa ndipo zimakhudza kwambiri. Chifukwa, kudzikonda phasing zikachitika, particles adzakhala mu gawo lililonse munda m'dera mofulumira. zotsatira wina ndi grouping iwo mu nthawi kupanga nthinthi osati mtsinje mosalekeza.

Malangizo a mtengo wa

Yofunika kwambiri mmene ntchito ndi tinthu accelerator, kusewera ndi mphamvu ya maginito, pamene iwo akhoza kusintha malangizo a m'gulu lawo. Zimenezi zikutanthauza kuti angagwiritsidwe ntchito "kupinda" wa mtengo panjira zozungulira, kotero iwo mobwerezabwereza anadutsa chomwecho mofulumira gawo. Pankhani losavuta pa tinthu mlandu kusunthira pa mlingo woyenerera malangizo a m'munda homogeneous maginito, mphamvu vekitala perpendicular kwa onse kuyenda ake, ndipo kumunda. Izi zimapangitsa mtengo kusamukira ku njira zozungulira perpendicular kumunda, mpaka idzatulukira munda wake wa kanthu kapena mphamvu akuyamba kuchitapo kanthu. Amenewa ntchito accelerators ozungulira monga synchrotron ndi cyclotron. Mu cyclotron ndi m'munda zonse amapangidwa ndi maginito lalikulu. Particles ndi kuchuluka kwa mphamvu zawo Kupita spirally kunja inapita patsogolo ndi aliyense zisinthe. The synchrotron kuundana muziyendayenda mphete ndi utali wozungulira zonse, ndi m'munda kwaiye electromagnets kuzungulira ukuwonjezeka mphete monga particles ali inapita patsogolo. The maginito kupereka "kupinda" ankaimira dipoles ndi kumpoto ndi mizati kum'mwera, anawerama mu mawonekedwe horseshoe kuti mtengo angaphunzitse therebetween.

Zofunika ntchito yachiwiri ya electromagnets ndi kuganizira za matabwa kotero kuti iwo ali ndi lopapatiza kwambiri ngati nkotheka. Mawonekedwe zosavuta maginito moganizira - ndi mitengo anayi (awiri kumpoto ndi kum'mwera awiri) ili moyang'anana. Iwo kukankha particles ku malo mu njira imodzi, koma kuwalola kuti anagawira mu perpendicular. Quadrupole maginito kuganizira mtengo horizontally, polola kupita cholinga vertically. Kuti tichite zimenezi, iwo ayenera kugwiritsidwa ntchito awiriawiri. Kwa zolondola moganizira amagwiritsidwa ntchito maginito chipangizo kwambiri ndi ambiri mizati (6 ndi 8).

Popeza mphamvu ya ukuwonjezeka ndi tinthu, mphamvu ya m'munda maginito, akuwatsogolera ukuwonjezeka. Izi amasunga mtanda pa njira yodutsamo chomwecho. The curd anadzetsa mphete ndipo inapita patsogolo ndi mphamvu anakhumba pamaso akhoza kudzipatula ndipo ntchito mu zatsopano. Anabweza zimatheka ndi electromagnets amene adamulowetsa kukankhira particles kuchokera synchrotron mphete.

kugunda

Adawalamulira tinthu accelerators ntchito mankhwala ndi malonda, makamaka kutulutsa mtengo cholinga makamaka, mwachitsanzo, walitsa kapena ion implantation. Izi zikutanthauza kuti particles ntchito kamodzi. The N'chimodzimodzinso accelerators ntchito kafukufuku zofunika kwa zaka zambiri. Koma mphete amenewa anayamba mu 1970, imene matabwa awiri kufalitsidwa mbali zosiyana ndi adzawombana mozungulira dera la. The mwayi waukulu omwe zoterezi ndi mu mazunzo kugunda mphamvu ya particles amapita mwachindunji mogwirizana mphamvu pakati pawo. Izi umasiyana ndi zomwe zimachitika pamene mtengo collides ndi zithunzi n'kupuma, zimene zinachitikira kwambiri mphamvu amapita ku kuchepetsa zinthu chandamale zoyenda, malinga ndi mfundo za kusamala patsogolo.

Ena makina colliding matabwa pomanga ndi mphete ziwiri, intersecting mu malo awiri kapena kuposa, imene akufalitsa mbali zosiyana, particles wa mtundu womwewo. Wamba collider tinthu-antiparticle. Antiparticle ali mlandu wosiyana particles kugwirizana. Mwachitsanzo, positron, ndithu mlandu, ndipo ma elekitironi - zoipa. Izi zikutanthauza kuti munda kuti Iyamba Kuthamanga elekitironi, ndi positron kubweza pansi, akusuntha mu njira yomweyo. Koma ngati ukusunthira yamasika zosiyana, izo imathandizira. Mofananamo, munthu elekitironi akuyenderera ndi maginito chifuniro pamapindikira lamanzere, ndi positron - bwino. Koma ngati positron ikupita patsogolo, ndiye mayendedwe ake adzapitiriza panjira ya kudzanja lamanja, koma pa pamapindikira mofanana elekitironi lapansi. Komabe, izi zikutanthauza kuti particles akhoza kusuntha mwa mphete za synchrotron maginito chomwecho ndipo inapita patsogolo ndi minda chomwecho magetsi mbali zosiyana. Pa mfundo imeneyi analenga colliders zambiri zamphamvu colliding matabwa, T. Kwa. Kokha kumafuna munthu mphete accelerator.

Mtengo uli synchrotron ndi chikubwera mosalekeza ndi Integrated mu "clumps." Iwo akhoza kukhala masentimita angapo m'litali ndi limodzi la magawo khumi la millimeter awiri, ndipo akupanga za 10 ¹² particles. Izi kachulukidwe otsika, chifukwa kukula kwa zinthu lili ^{23 October} maatomu. Choncho, matabwa colliding intersect, pali mwina ang'ono kuti particles adzakhala chiyani wina ndi mzake. Zochita kuundana kupitiriza muziyendayenda mphete ndi kudzakomananso. Mkulu zingalowe mu accelerator wa particles mlandu (10 ^-11 mamilimita Hg. V.) Kodi chofunika kuti particles akhoza zimafala kwa maola ambiri popanda mwansanga ndi tinthu mpweya. Choncho, mphete amatchedwanso chokhala, chifukwa matabwa kwenikweni kusungidwa m'menemo maola angapo.

kulembetsa

Adawalamulira tinthu accelerators mu unyinji mukhoza kukawerenga kumachitika pamene particles kumalondolera chandamale kapena mtengo zina, kusuntha kwina. Mu televizioni chithunzi chubu, ma elekitironi kwa mfuti kukapha phosphor chophimba padziko mkati ndi zimatulutsa kuwala imene potero recreates fano opatsirana. Mu accelerators ngati zoyesera apadera anatani particles anabalalika, koma iwo kawirikawiri cholinga polenga chizindikiro magetsi kuti zikhoza kusinthidwa mu deta kompyuta ndi kusanthula ntchito kompyuta. adawalamulira Only zinthu kubala chizindikiro magetsi kudutsa chuma, mwachitsanzo ionization kapena malemeredwe maatomu, ndipo angathe kuonedwa mwachindunji. The particles ndale monga neutrons kapena photons angathe kuonedwa mwa njira zina mwa khalidwe la particles adawalamulira kuti iwo akutero.

Pali zambiri zoyesera apadera. Ena mwa iwo, monga Geiger kauntala, chiwerengero tinthu, ndi ntchito zina, mwachitsanzo, kwa mayendedwe kujambula kapena mathamangidwe muyeso wa mphamvu. zoyesera zamakono kukula ndi luso, zosiyanasiyana kuyambira wamng'ono mlandu zolumukizidwa zipangizo kuti lalikulu zipinda mpweya odzazidwa ndi mawaya omwe kudziwa mayendedwe ionized umatulutsa particles mlandu.

nkhani

Adawalamulira tinthu accelerators makamaka zithandize maphunziro a katundu wa mtima atomiki ndi tinthu pulayimale. Popeza kutsegula kwa sayansi British Ernest Rutherford mu 1919, zochita za asafe phata ndi Alpha tinthu, kufufuza zonse m'munda wa sayansi ya nyukiliya mpaka mu 1932 kunachitika ndi mtima helium, anamasulidwa ndi kuvunda kwa zinthu zachilengedwe nyukiliya. Natural alpha-particles ndi mphamvu kayendedwe 8 MeV, koma Rutherford anakhulupirira kuti ayenera kukhala chongopeka inapita patsogolo makhalidwe ngakhale kuposa kuyan'anila oipa a mtima lolemera. Pa nthawi zimawoneka zovuta. Komabe, mawerengedwe anapanga mu 1928 ndi Georgiem Gamovym (pa University of Göttingen, Germany), anasonyeza kuti ayoni angagwiritsidwe ntchito pa mphamvu kwambiri m'munsi, ndipo izi lakusonkhezerani ankafuna kumanga malo omwe akutipatsa mtengo zokwanira Research nyukiliya.

zochitika zina za nyengo ino anasonyeza mfundo zimene adalamulira tinthu accelerators zimamangidwa lero. Woyamba zatsopano bwino ndi ayoni chongopeka inapita inachitika Cockroft ndi Walton mu 1932 ku University Cambridge. Pogwiritsa ntchito voteji multiplier, mapulotoni ali inapita patsogolo ndi 710 keV, ndipo anasonyeza kuti yotsirizira anatani ndi lifiyamu kupanga particles awiri Alpha. Pofika 1931, ku University Princeton ku New Jersey, Robert van de Graaff electrostatic lamba anamanga woyamba apamwamba angathe jenereta. Voteji multiplier Cockcroft-Walton magudumu ndi Van De Graaff jenereta akadali ntchito ngati zopangira magetsi accelerators.

Mfundo liniya resonant accelerator zinaoneka Rolf Widerøe mu 1928. The Rhine-Westphalian University zaumisiri Aachen, Germany, anagwiritsa ntchito mkulu AC voteji kuti imathandizira soda ndi potaziyamu ayoni kuti mphamvu owonjezera kawiri kuwauza. Mu 1931 mu United States Ernest Lourens ndi wachiwiri wake Davide Sloan ya University of California, Berkeley, ntchito m'minda mkulu-pafupipafupi kuti imathandizira Mercury ayoni kuti mphamvu kuposa 1.2 MeV. ntchito Izi lowonjezera accelerator molemera mlandu particles Wideröe, koma ion matabwa ndi Opanda kafukufuku nyukiliya.

Maginito kumveka accelerator kapena cyclotron, pathupi ngati masinthidwe a Lawrence Wideröe unsembe. Wophunzira Lawrence Livingston anasonyeza mfundo ya cyclotron mu 1931, kupanga ayoni ndi mphamvu 80 keV. Mu 1932, Lawrence ndi Livingston analengeza mathamangitsidwe wa mapulotoni mpaka oposa 1 MeV. Kenako mu 1930s, ndi mphamvu cyclotrons anafika pafupi 25 MeV, ndi Van De Graaff - za 4 MeV. Mu 1940, Donald Kerst, kugwiritsa ntchito zotsatira za kuwerengetsera mosamala kanjira dongosolo maginito, anamanga pa University of Illinois, ndi betatron choyamba, maginito kupatsidwa ulemu elekitironi accelerator.

sayansi amakono: tinthu accelerators

Nkhondo yachiwiri itatha panali patsogolo mofulumira mu sayansi ya mofulumira particles kuti mphamvu yapamwamba. Iwo anayamba Edwin McMillan pa Berkeley ndi Vladimir Veksler mu Moscow. Mu 1945, iwo ali onse paokha Chrixitu tafotokozeramu mfundo ya bata gawo. Mfundo imeneyi amapereka kudzera kukhala m'mipita khola la particles mu zozungulira accelerator kuti kuchotsedwa yosaloledwa mphamvu purotoni ndipo anathandiza kulenga maginito kumveka accelerators (synchrotrons) kwa ma elekitironi. Autophasing, kukhazikitsa mfundo ya bata gawo, lidatsirizika pambuyo yomanga synchrocyclotron kakang'ono pa yunivesite ya California ndi synchrotron ku England. Posakhalitsa, choyamba purotoni liniya resonant accelerator analengedwa. Mfundo imeneyi ntchito zonse zazikulu synchrotrons purotoni anamanga kuyambira pamenepo.

Mu 1947, William Hansen, pa University Stanford ku California, anamanga woyamba elekitironi liniya accelerator pa funde woyendayenda, amene anali mayikirowevu luso limene zithandize Rada pa Nkhondo Yachiwiri ya World.

Patsogolo kuphunzira zidatheka ndi kuwonjezeka purotoni mphamvu, zomwe zinachititsa kuti yomanga accelerators nthawi zazikulu. Vuto limeneli la mkulu kupanga ndalama yaikulu maginito mphete wakhala ndinayima. Yaikulu akulemera padziko 40,000 matani. Njira kuwonjezera mphamvu popanda kukula makina kukula anali ndisanabadwe m'ma 1952 godu Livingstone, Courant ndi Snyder njira ya alternating moganizira (limatchedwa amphamvu moganizira). Synchrotrons ntchito mfundo imeneyi, ntchito maginito nthawi 100 zing'onozing'ono kuposa kale. Chotero moganizira ntchito synchrotrons zamakono zonse.

Mu 1956 Kerst ndinazindikira kuti ngati waika awiri particles asungidwa pa intersecting m'mipita, inu mukhoza kuona iwo adzawombana. Kugwiritsa ntchito mfundo imeneyi chofunika kudzikundikira inapita mitanda m'zinthu, wotchedwa chokhala. Njira imeneyi lakwaniritsa ndi mphamvu pazipita particles mogwirizana.