Lub spectrum ntawm synchrotron hluav taws xob tsis yog qhov zoo. Ntawd yog, nws tuaj yeem muab faib ua ob peb hom nkaus xwb. Yog hais tias lub particle tsis yog relativistic, ces xws li hluav taws xob hu ua cyclotron emission. Yog tias, ntawm qhov tod tes, cov lus hais yog qhov sib txawv hauv qhov, ces cov hluav taws xob uas tshwm sim los ntawm lawv cov kev sib cuam tshuam qee zaum hu ua ultrarelativistic. Synchronous hluav taws xob tuaj yeem ua tiav los ntawm cov khoom siv dag zog (hauv synchrotrons lossis cia rings) los yog vim yog cov hluav taws xob ceev ceev txav los ntawm cov chaw sib nqus. Cov hluav taws xob yog li tsim muaj cov yam ntxwv polarization, thiab cov zaus tsim tawm tuaj yeem sib txawv ntawm tag nrho cov electromagnetic spectrum, tseem hu ua hluav taws xob txuas ntxiv.
Qhib
Qhov tshwm sim no tau muaj npe tom qab General Electric synchrotron generator ua rau xyoo 1946. Nws lub neej tau tshaj tawm thaum lub Tsib Hlis 1947 los ntawm cov kws tshawb fawb Frank Elder, Anatoly Gurevich, Robert Langmuir thiab tshuaj ntsuab. Pollock hauv nws tsab ntawv "Radiation los ntawm electrons hauv synchrotron". Tab sis qhov no tsuas yog kev tshawb nrhiav theoretical xwb, koj yuav tau nyeem txog thawj qhov kev soj ntsuam tiag tiag ntawm qhov tshwm sim hauv qab no.
khoom
Thaum cov khoom siv hluav taws xob siab nyob hauv qhov nrawm, suav nrog cov hluav taws xob yuam kom txav mus raws txoj kev nkhaus los ntawm qhov chaw sib nqus, cov hluav taws xob synchrotron raug tsim. Qhov no zoo ib yam li lub kav hlau txais xov xov tooj cua, tab sis nrog qhov sib txawv ntawm qhov theoretically qhov kev sib raug zoo ceev yuav hloov qhov kev pom ntau zaus vim Doppler nyhuv los ntawm Lorentz coefficient γ. Qhov luv luv ntawm qhov ntev ntawm qhov sib npaug ces hits qhov zaus pom los ntawm lwm yam γ, yog li ua kom lub zaus GHz ntawm lub resonant kab noj hniav uas accelerates cov electrons nyob rau hauv X-ray ntau. Lub zog hluav taws xob yog txiav txim siab los ntawm cov qauv Larmor relativistic, thiab lub zog ntawm cov hluav taws xob hluav taws xob yog txiav txim siab los ntawm Abraham-Lorentz-Dirac force.
Lwm yam nta
Cov qauv hluav taws xob tuaj yeem hloov pauv los ntawm tus qauv isotropic dipole mus rau hauv lub khob hluav taws xob uas muaj hluav taws xob zoo heev. Electron synchrotron hluav taws xob yog qhov ci ntsa iab tshaj plaws ntawm X-rays.
Lub geometry ntawm cov phiaj xwm acceleration zoo li ua rau cov hluav taws xob linearly polarized thaum saib hauv lub dav hlau ntawm lub orbit thiab ncig polarized thaum saib ntawm lub kaum sab xis rau lub dav hlau. Amplitude thiab zaus, txawm li cas los xij, yog nyob rau ntawm qhov polar ecliptic.
Lub hauv paus ntawm cov hluav taws xob synchrotron kuj yog qhov chaw ntawm hluav taws xob hluav taws xob hluav taws xob (EM), uas yogib lub nplhaib cia tsim los rau kev tshawb fawb thiab kev ua haujlwm. Qhov hluav taws xob no yog tsim tsis tau tsuas yog los ntawm kev cia lub nplhaib, tab sis kuj los ntawm lwm yam tshwj xeeb particle accelerators, feem ntau accelerating electrons. Thaum lub zog hluav taws xob hluav taws xob muaj hluav taws xob tau tsim tawm, nws raug xa mus rau cov khoom siv xws li bending hlau nplaum thiab cov khoom siv ntxig (undulators lossis wigglers). Lawv muab cov hlau nplaum muaj zog, cov kab hluav taws xob txuas ntxiv, uas tsim nyog los hloov cov hluav taws xob hluav taws xob siab rau hauv photons.
Siv cov hluav taws xob synchrotron
Cov ntawv thov tseem ceeb ntawm lub teeb synchrotron yog condensed teeb meem physics, cov ntaub ntawv science, biology thiab tshuaj. Feem ntau ntawm cov kev sim siv lub teeb synchrotron muaj feem xyuam rau txoj kev tshawb fawb ntawm cov qauv ntawm cov teeb meem los ntawm qib sub-nanometer ntawm cov qauv hluav taws xob mus rau qib ntawm micrometer thiab millimeter, uas yog qhov tseem ceeb rau kev kho mob. Ib qho piv txwv ntawm daim ntawv thov kev lag luam yog kev tsim cov microstructures siv cov txheej txheem LIGA.
Synchrotron hluav taws xob kuj yog tsim los ntawm cov khoom siv hnub qub, feem ntau qhov chaw sib txheeb electrons kauv (thiab yog li ntawd hloov ceev) los ntawm magnetic teb.
History
Cov hluav taws xob no tau pom thawj zaug hauv lub foob pob hluav taws raug rho tawm los ntawm Messier 87 hauv xyoo 1956 los ntawm Geoffrey R. Burbidge, uas pom nws yog qhov kev lees paub ntawm Iosif Shklovsky qhov kev kwv yees hauv xyoo 1953, tab sis nws tau kwv yees ua ntej los ntawm Hannes Alfven thiab Nikolai Herlofson hauv Xyoo 1950. Hnub ci hluav taws xob nrawm cov khoomuas tawm hauv txoj kev no, raws li tau hais los ntawm R. Giovanolli hauv xyoo 1948 thiab tau piav qhia los ntawm Piddington hauv xyoo 1952.
Space
Cov qhov dub loj heev tau thov los tsim cov hluav taws xob synchrotron los ntawm kev thawb lub dav hlau tsim los ntawm gravitationally accelerating ions los ntawm supercorded "tubular" polar cheeb tsam ntawm magnetic teb. Cov dav hlau zoo li no, qhov ze tshaj plaws ntawm lawv hauv Messier 87, tau txheeb xyuas los ntawm Hubble telescope li superluminal signals tsiv ntawm qhov zaus ntawm 6 × s (rau lub sijhawm ntawm lub teeb nrawm) los ntawm peb lub hnub qub. Qhov tshwm sim no yog tshwm sim los ntawm cov dav hlau mus ncig ze rau qhov ceev ntawm lub teeb thiab ntawm lub kaum sab xis me me rau cov neeg soj ntsuam. Vim hais tias cov dav hlau ceev ceev emit lub teeb ntawm txhua qhov chaw raws lawv txoj kev, lub teeb lawv emission tsis mus ze rau tus soj ntsuam sai npaum li cas lub dav hlau nws tus kheej. Lub teeb emitted tshaj ntau pua xyoo ntawm kev mus ncig yog li mus txog rau cov neeg soj ntsuam nyob rau lub sij hawm luv luv (10 los yog nees nkaum xyoo). Tsis muaj kev ua txhaum ntawm txoj kev xav tshwj xeeb ntawm kev sib txheeb hauv qhov tshwm sim no.
Ib impulsive emission of gamma radiation from a nebula with a brightness of up to ≧25 GeV tsis ntev los no tau raug kuaj pom, tej zaum vim synchrotron emission los ntawm electrons cuab nyob rau hauv ib tug muaj zog magnetic teb nyob ib ncig ntawm lub pulsar. Ib chav kawm ntawm astronomical qhov chaw uas synchrotron emission tseem ceeb yog pulsar cua nebulae, los yog plerions, uas Crab Nebula thiab nws cov pulsar txuam yog archetypal. Polarization hauv Crab Nebula ntawm lub zog ntawm 0.1 thiab 1.0 MeV yog cov hluav taws xob synchrotron.
Luv luv txog kev suav thiab kev sib tsoo
Hauv kev sib npaug ntawm cov ntsiab lus no, cov ntsiab lus tshwj xeeb lossis qhov muaj txiaj ntsig feem ntau tau sau, cim cov khoom uas ua rau lub npe nrov tshaj plaws. Cov ntsiab lus no sawv cev rau cov txiaj ntsig ntawm qhov particle qhov chaw zoo li qub, uas yog qhov ua haujlwm ntawm xoom lossis qhov nrawm nrawm ntawm nws cov lus tsa suab. Ntawm qhov tsis sib xws, lub sij hawm thib ob poob tawm raws li qhov sib cuam tshuam ntawm thawj lub zog ntawm qhov kev ncua deb ntawm qhov chaw, thiab qee cov ntsiab lus yog hu ua acceleration field los yog hluav taws xob teb vim tias lawv yog cov khoom ntawm thaj teb vim qhov nrawm ntawm tus nqi (hloov ceev).
Yog li, lub zog hluav taws xob yog ntsuas raws li lub zog ntawm plaub lub zog. Qhov hluav taws xob no txwv lub zog ntawm electron-positron ncig collider. Feem ntau, proton colliders hloov pauv los ntawm qhov siab tshaj plaws magnetic teb. Yog li, piv txwv li, Loj Hadron Collider muaj qhov nruab nrab ntawm lub zog loj 70 npaug ntau dua li lwm cov khoom siv accelerator, txawm tias qhov loj ntawm ib qho proton yog 2000 npaug ntawm ib qho hluav taws xob.
Terminology
Kev sib txawv ntawm kev tshawb fawb feem ntau muaj ntau txoj hauv kev los txhais cov ntsiab lus. Hmoov tsis zoo, nyob rau hauv qhov chaw ntawm X-rays, ob peb lo lus txhais tau tias tib yam li "kua hluav taws xob". Qee tus kws sau ntawv siv lo lus "brightness", uas yog ib zaug siv los xa mus rau photometric brightness, los yog siv tsis raug raucov npe ntawm cov hluav taws xob radiometric. Kev siv zog txhais tau hais tias lub zog ntom ntom ntawm ib cheeb tsam, tab sis rau qhov chaw xoo hluav taws xob feem ntau txhais tau tias ci ntsa iab.
Mechanism ntawm qhov tshwm sim
Synchrotron hluav taws xob tuaj yeem tshwm sim hauv cov accelerators xws li qhov tsis tau pom dua, ua rau tsis xav tau lub zog poob rau hauv cov ntsiab lus ntawm particle physics, los yog txhob txwm tsim hluav taws xob qhov chaw rau ntau daim ntawv thov kev sim. Cov hluav taws xob tau nrawm mus rau qhov nrawm hauv ob peb kauj ruam kom ncav cuag lub zog kawg uas feem ntau yog nyob rau hauv ntau yam gigaelectronvolt. Cov hluav taws xob raug yuam kom txav mus rau hauv txoj kev kaw los ntawm cov hlau nplaum muaj zog. Nws zoo ib yam li cov kav hlau txais xov xov tooj cua, tab sis nrog qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv ntawm qhov kev soj ntsuam ntau zaus vim Doppler nyhuv. Relativistic Lorentz contraction cuam tshuam rau gigahertz zaus, yog li muab nws nyob rau hauv lub resonant kab noj hniav uas accelerates electrons rau hauv X-ray ntau. Lwm qhov ua tau zoo ntawm kev sib raug zoo yog tias cov qauv hluav taws xob yog distorted los ntawm cov qauv isotropic dipole xav tau los ntawm cov kev xav tsis sib xws rau cov hluav taws xob hluav taws xob tsis tshua muaj siab. Qhov no ua rau synchrotron hluav taws xob diffraction yog txoj hauv kev zoo tshaj plaws los tsim X-rays. Lub tiaj tus acceleration geometry ua rau cov hluav taws xob linearly polarized thaum saib hauv lub dav hlau ntawm lub orbit thiab tsim cov voj voog polarization thaum saib ntawm lub kaum sab xis me ntsis rau lub dav hlau no.
Ntau yam siv
Cov txiaj ntsig ntawm kev sivsynchrotron hluav taws xob rau spectroscopy thiab diffraction tau siv los ntawm cov zej zog kev tshawb fawb puas tau loj hlob txij li xyoo 1960 thiab 1970s. Thaum pib, accelerators tau tsim rau particle physics. Lub "parasitic hom" siv cov hluav taws xob synchrotron, qhov twg cov bending magnetic radiation yuav tsum tau muab rho tawm los ntawm drilling ntxiv qhov nyob rau hauv cov hlab ntsha. Thawj lub nplhaib khaws cia tau qhia raws li lub teeb ci synchrotron yog Tantalus, uas tau pib ua ntej xyoo 1968. Raws li cov hluav taws xob accelerator tau dhau los ua khaus thiab nws cov ntawv thov tau txais txiaj ntsig zoo dua, cov khoom siv uas txhim kho nws qhov kev siv zog tau tsim rau hauv cov nplhaib uas twb muaj lawm. Txoj kev synchrotron radiation diffraction method tau tsim thiab ua kom zoo txij thaum pib kom tau txais X-rays zoo. Cov khoom siv thib plaub tau raug txiav txim siab, uas yuav suav nrog ntau lub tswv yim los tsim kev ua kom muaj zog ultra-brilliant, pulsed, timed structural X-rays rau qhov xav tau heev thiab tej zaum tseem tsis tau tsim kev sim.
Thawj khoom siv
Thaum xub thawj, khoov electromagnets hauv accelerators tau siv los tsim cov hluav taws xob no, tab sis lwm yam khoom siv tshwj xeeb, cov khoom siv ntxig, qee zaum siv los tsim cov teeb pom kev zoo. Cov txheej txheem ntawm synchrotron hluav taws xob diffraction (thib peb tiam) feem ntau yog nyob ntawm cov khoom siv, qhov chaw ncaj nraim ntawm lub nplhaib cia muaj lub sijhawm. Sib nqus cov qauv (muaj ntau cov hlau nplaum nyob rau hauv daim ntawv ntawm alternating N thiab S ncej) uas ua rau electrons txav mus rau hauv txoj kev sinusoidal los yog kauv. Yog li, es tsis txhob ntawm ib qho khoov, ntau kaum lossis ntau pua ntawm "swirls" nyob rau hauv qhov kev xam tau tseeb ntxiv los yog muab ntau qhov kev siv ntawm cov nqaj. Cov khoom siv no hu ua wigglers lossis undulators. Lub ntsiab sib txawv ntawm ib tug undulator thiab ib tug wiggler yog qhov kev siv ntawm lawv magnetic teb thiab lub amplitude ntawm lub deviation ntawm txoj kev ncaj qha ntawm cov electrons. Tag nrho cov cuab yeej thiab cov cuab yeej tam sim no tau muab khaws cia ntawm Lub Chaw rau Synchrotron Radiation (USA).
Txhob Cia Siab
Lub accumulator muaj qhov tso cai rau cov khoom tawm ntawm cov hluav taws xob tom qab thiab ua raws cov kab ntawm cov nqaj mus rau tus kws sim lub tshuab nqus tsev. Ntau cov kab teeb ci no tuaj yeem los ntawm cov khoom siv hluav taws xob synchrotron thib peb niaj hnub no.
Electrons tuaj yeem muab rho tawm los ntawm qhov tseeb accelerator thiab khaws cia rau hauv ib qho chaw pabcuam ultra-high nqus hlau nplaum cia, los ntawm qhov chaw uas lawv tuaj yeem muab rho tawm (thiab qhov twg lawv tuaj yeem tsim dua) ntau zaus. Cov hlau nplaum nyob rau hauv lub nplhaib yuav tsum tau rov ua dua cov nqaj tawm tsam "Coulomb rog" (lossis, yooj yim dua, qhov chaw tsub) uas nyiam ua kom puas cov khoom siv hluav taws xob. Kev hloov ntawm cov kev taw qhia yog ib daim ntawv ntawm acceleration, vim hais tias electrons emit hluav taws xob ntawm lub siab energies thiab high acceleration speeds nyob rau hauv ib tug particle accelerator. Raws li txoj cai, lub ci ci ntawm cov hluav taws xob synchrotron kuj nyob ntawm tib qhov ceev.
