Cherenkov hluav taws xob yog cov tshuaj tiv thaiv hluav taws xob uas tshwm sim thaum cov khoom siv hluav taws xob hla dhau los ntawm qhov nruab nrab pob tshab ntawm qhov nrawm dua li tib theem ntsuas ntawm lub teeb hauv tib qhov nruab nrab. Cov yam ntxwv xiav ci ntawm lub underwater nuclear reactor yog vim qhov kev cuam tshuam no.
History
Cov hluav taws xob muaj npe tom qab tus kws tshawb fawb Soviet Pavel Cherenkov, 1958 Nobel nqi zog. Nws yog nws thawj zaug pom nws sim nyob rau hauv kev saib xyuas ntawm ib tug npoj yaig nyob rau hauv 1934. Yog li ntawd, nws tseem hu ua Vavilov-Cherenkov effect.
Ib tug kws tshawb fawb pom lub teeb ci ntsa iab nyob ib puag ncig cov tshuaj siv hluav taws xob hauv dej thaum sim. Nws daim ntawv pov thawj kws kho mob yog nyob rau ntawm luminescence ntawm kev daws teeb meem ntawm uranium ntsev, uas tau zoo siab los ntawm gamma rays es tsis txhob muaj lub zog pom lub teeb, zoo li feem ntau ua tiav. Nws tshawb pom anisotropy thiab xaus lus tias qhov teebmeem no tsis yog qhov tshwm sim fluorescent.
Cherenkov txoj kev xavTom qab hluav taws xob tau tsim nyob rau hauv lub moj khaum ntawm Einstein txoj kev xav ntawm kev sib raug zoo los ntawm tus kws tshawb fawb cov npoj yaig Igor Tamm thiab Ilya Frank. Lawv kuj tau txais 1958 Nobel nqi zog. Tus qauv Frank-Tamm piav qhia txog tus nqi ntawm lub zog emissions los ntawm radiated hais ib chav tsev ntev mus rau ib chav tsev zaus. Nws yog qhov refractive index ntawm cov khoom uas tus nqi dhau.
Cherenkov hluav taws xob raws li conical wavefront tau kwv yees los ntawm lus Askiv polymath Oliver Heaviside hauv cov ntaub ntawv luam tawm ntawm 1888 thiab 1889, thiab los ntawm Arnold Sommerfeld hauv 1904. Tab sis ob qho tib si tau hnov qab sai sai tom qab qhov kev txwv ntawm superparticle relativity mus txog rau xyoo 1970. Marie Curie pom lub teeb xiav daj nyob rau hauv ib qho kev daws teeb meem ntawm radium hauv xyoo 1910, tab sis tsis tau mus rau hauv cov ntsiab lus. Xyoo 1926, cov kws kho mob Fabkis txoj xov tooj cua coj los ntawm Lucien tau piav qhia txog cov hluav taws xob luminous ntawm radium, uas muaj cov spectrum tsis tu ncua.
Lub Cev Keeb Kwm
Txawm hais tias electrodynamics txiav txim siab tias qhov ceev ntawm lub teeb hauv lub tshuab nqus tsev yog ib qho universal tas li (C), tus nqi ntawm lub teeb propagates hauv nruab nrab yuav tsawg dua C. Qhov ceev tuaj yeem nce thaum muaj kev cuam tshuam nuclear thiab hauv particle accelerators.. Tam sim no nws paub meej rau cov kws tshawb fawb tias Cherenkov hluav taws xob tshwm sim thaum lub hluav taws xob them hluav taws xob dhau los ntawm qhov nruab nrab pob tshab.
Qhov kev sib piv ib txwm yog lub suab nrov ntawm lub dav hlau nrawm nrawm. Cov nthwv dej no, tsim los ntawm lub cev reactive,propagate ntawm qhov ceev ntawm lub teeb liab nws tus kheej. Cov khoom sib txawv qeeb dua li qhov khoom txav, thiab tsis tuaj yeem ua ntej ntawm nws. Hloov chaw, lawv tsim ib qho kev cuam tshuam pem hauv ntej. Ib yam li ntawd, cov khoom siv hluav taws xob tuaj yeem ua rau lub teeb poob siab thaum nws dhau los ntawm qee qhov nruab nrab.
Tsis tas li ntawd, qhov ceev yuav tsum dhau yog theem ceev, tsis yog pab pawg ceev. Cov qub tuaj yeem hloov pauv tau los ntawm kev siv lub sijhawm nruab nrab, qhov twg ib tus tuaj yeem tau txais Cherenkov hluav taws xob yam tsis muaj qhov tsawg kawg nkaus tshaj tawm. Qhov tshwm sim no hu ua Smith-Purcell effect. Nyob rau hauv ib tug complex periodic nruab nrab, xws li ib tug photonic siv lead ua, ntau lwm yam anomalous tshua kuj yuav tau, xws li hluav taws xob nyob rau hauv lub opposite direction.
Yuav ua li cas hauv lub reactor
Hauv lawv cov ntaub ntawv qub ntawm lub hauv paus theoretical, Tamm thiab Frank tau sau tias: "Cherenkov hluav taws xob yog cov tshuaj tiv thaiv tshwj xeeb uas pom tau tias tsis tuaj yeem piav qhia los ntawm cov txheej txheem dav dav, xws li kev cuam tshuam ntawm hluav taws xob ceev nrog ib lub atom lossis hluav taws xob. tawg mus rau hauv nuclei Ntawm qhov tod tes, qhov tshwm sim no tuaj yeem piav qhia ob qho tib si zoo thiab ntau, yog tias peb xav txog qhov tseeb tias lub tshuab hluav taws xob txav mus rau hauv nruab nrab emits lub teeb, txawm tias nws txav tsis sib xws, yog tias nws ceev yog ntau dua li ntawm. teeb."
Txawm li cas los xij, muaj qee qhov kev xav tsis zoo txog Cherenkov hluav taws xob. Piv txwv li, nws tau txiav txim siab tias qhov nruab nrab ua polarized los ntawm hluav taws xob ntawm cov khoom. Yog tias tom kawg txav mus qeeb, ces qhov kev txav rov qab mus raumechanical tshuav nyiaj li cas. Txawm li cas los xij, thaum lub molecule txav nrawm txaus, qhov txwv tsis pub teb ceev ntawm qhov nruab nrab txhais tau hais tias qhov sib npaug tseem nyob hauv nws txoj kev sawv, thiab lub zog muaj nyob hauv nws yog radiated nyob rau hauv daim ntawv ntawm ib coherent shock yoj.
Cov ntsiab lus zoo li no tsis muaj kev tshuaj xyuas qhov tseeb, txij li cov hluav taws xob hluav taws xob hluav taws xob tau tawm thaum cov khoom siv hluav taws xob txav mus rau hauv qhov nruab nrab homogeneous ntawm subluminal speeds, uas tsis suav tias yog Cherenkov hluav taws xob.
Reverse phenomenon
Cov nyhuv Cherenkov tuaj yeem tau txais los ntawm cov khoom hu ua metamaterials nrog qhov ntsuas tsis zoo. Ntawd yog, nrog subwavelength microstructure, uas ua rau lawv muaj txiaj ntsig "nruab nrab" cov cuab yeej uas txawv ntawm lwm tus, qhov no muaj qhov tsis zoo permittivity. Qhov no txhais tau hais tias thaum tus nqi them dhau los ntawm qhov nruab nrab nrawm dua li theem tshaj tawm, nws yuav tawm hluav taws xob los ntawm nws txoj kev hla mus rau pem hauv ntej.
Nws tseem tuaj yeem tau txais Cherenkov hluav taws xob nrog lub khob hliav qab hauv cov xov xwm tsis yog metamaterial. Ntawm no, cov qauv yog nyob rau tib lub teev raws li lub wavelength, yog li nws tsis tuaj yeem suav hais tias yog ib qho zoo sib xws metamaterial.
Ntse
Tsis zoo li fluorescence lossis emission spectra, uas muaj cov yam ntxwv ncov, Cherenkov hluav taws xob txuas mus ntxiv. Nyob ib ncig ntawm qhov pom glow, qhov txheeb ze ntawm ib chav tsev zaus yog kwv yees liproportional rau nws. Qhov ntawd yog, cov nqi siab dua yog khaus.
Qhov no yog vim li cas pom Cherenkov hluav taws xob yog xiav xiav. Nyob rau hauv qhov tseeb, feem ntau ntawm cov txheej txheem yog nyob rau hauv lub ultraviolet spectrum - tsuas yog nrog txaus tsub kom ceev nws yuav pom. Lub rhiab heev ntawm tib neeg lub qhov muag peaks nyob rau hauv ntsuab thiab yog tsawg heev nyob rau hauv lub violet ib feem ntawm lub spectrum.
Nuclear reactors
Cherenkov hluav taws xob yog siv los kuaj xyuas cov khoom siv hluav taws xob siab. Nyob rau hauv cov chav xws li nuclear reactors, beta electrons raug tso tawm raws li fission decay khoom. Lub ci txuas ntxiv tom qab cov tshuaj tiv thaiv kab mob nres, dimming raws li cov khoom siv luv luv. Tsis tas li ntawd, Cherenkov hluav taws xob tuaj yeem ua tus yam ntxwv ntawm cov khoom siv hluav taws xob ntxiv ntawm cov khoom siv roj. Qhov tshwm sim no yog siv los xyuas seb puas muaj cov roj nuclear siv hauv cov tso tsheb hlau luam.
