Big Bang ua rau muaj qhov sib npaug ntawm cov teeb meem thiab cov tshuaj tiv thaiv uas yuav tsum tau rhuav tshem ib leeg tawm hauv qab lub ntiaj teb khoob. Txawm li cas los xij, qhov teeb meem muaj sia nyob thiab tswj hwm lub ntiaj teb thaum antimatter ploj mus. Nws tau xav tias qee qhov tsis paub qhov sib txawv hauv cov khoom nruab nrab ntawm cov khoom thiab cov khoom siv sib txuas yuav ua rau lub luag haujlwm rau qhov no. Kev ntsuas siab ntawm cov khoom tseem ceeb ntawm antiprotons muaj peev xwm ua kom nkag siab txog qhov teeb meem-antimatter asymmetry. Nws yuav tsum tau muab cov tshuaj antiprotons. Tam sim no, CERN's Antiproton Decelerator (AD) yog tib lub chaw uas cov tshuaj tiv thaiv tau tsim thiab khaws cia. Nws tsis tuaj yeem ua qhov kev tshawb fawb siab ntawm antiprotons nyob ze AD vim yog qhov hloov pauv ntawm magnetic teb tsim los ntawm accelerators. Yog li ntawd, kev thauj cov tshuaj antiprotons los ntawm qhov chaw no mus rau lwm lub chaw kuaj mob yog qhov tseem ceeb. Tam sim no, tsis muaj cov cuab yeej tsim nyog ua li ntawd. BASE-STEP yog ib kauj ruam mus rau hauv qhov kev taw qhia no. Nws yog ib qho khoom siv me me uas tsim los khaws thiab thauj cov tshuaj tiv thaiv kab mob los ntawm CERN qhov chaw mus rau lub chaw soj nstuam ntawm lwm qhov chaw rau kev tshawb fawb siab ntawm antimatter. Thaum Lub Kaum Hli 24, 2024, BASE-STEP tau ua ib qho kev ua yeeb yam zoo tshaj plaws los ntawm kev siv cov khoom pov tseg protons los ua ib qho kev sawv cev rau cov tshuaj tiv thaiv. Nws thauj huab cua ntawm 70 protons hauv zos hauv lub tsheb thauj khoom. Qhov no yog thawj zaug ntawm kev thauj mus los ntawm cov khoom xoob hauv cov cuab yeej rov qab siv tau thiab yog ib qho tseem ceeb ntawm kev tsim cov kev pabcuam antiproton-xa mus rau kev sim ntawm lwm lub chaw soj nstuam. Nrog qee qhov kev kho kom zoo hauv cov txheej txheem, antiprotons tau npaj yuav thauj hauv 2025.
Thaum pib, lub Big Bang tsim cov khoom sib npaug ntawm cov teeb meem thiab cov tshuaj tiv thaiv. Ob leeg zoo ib yam hauv cov khoom, tsuas yog tias lawv muaj cov nqi sib txawv, thiab lawv lub sijhawm sib nqus tau thim rov qab.
Qhov teeb meem thiab antimatter yuav tsum tau rhuav tshem sai sai uas tawm hauv qab lub ntug khoob tab sis qhov ntawd tsis tshwm sim. Lub ntiaj teb tam sim no yog tag nrho los ntawm cov teeb meem thaum antimatter ploj lawm. Qhov no yog xav tias muaj qee qhov tsis paub qhov txawv ntawm qhov tseem ceeb ntawm cov khoom thiab lawv cov khoom sib thooj uas yuav ua rau muaj sia nyob ntawm qhov teeb meem thaum antimatter raug tshem tawm ua rau muaj teeb meem-antimatter asymmetry.
Raws li CPT (Charge, Parity, thiab Time reversal) symmetry, uas yog ib feem ntawm Standard Model ntawm particle physics, cov khoom tseem ceeb ntawm cov khoom yuav tsum sib npaug thiab ib nrab rov qab rau cov ntawm lawv cov antiparticles coj. Kev ntsuas kev ntsuas siab ntawm qhov sib txawv ntawm cov cuab yeej yooj yim (xws li pawg, nqi, lub neej lossis lub sijhawm sib nqus) ntawm cov khoom thiab lawv cov khoom sib txuas tuaj yeem pab tau kom nkag siab qhov teeb meem-antimatter asymmetry. Qhov no yog cov ntsiab lus ntawm CERN's Baryon Kev sim Antibaryon Symmetry (BASE).
Kev sim BASE tau tsim los tshawb xyuas Proton Antiproton Symmetry los ntawm kev ua cov kev ntsuas siab ntawm cov khoom (xws li lub sijhawm sib nqus sib nqus) ntawm cov tshuaj tiv thaiv nrog cov fractional precision nyob rau hauv kev txiav txim ntawm ib feem-ib-billion. Cov kauj ruam tom ntej yog kev sib piv ntawm cov kev ntsuas no nrog cov nqi sib xws rau cov protons. Rau lub sijhawm sib nqus sib nqus, tag nrho cov txheej txheem yog raws li kev ntsuas ntawm Larmor zaus thiab cyclotron zaus.
Tam sim no, CERN's Antiproton Decelerator (AD) yog tib lub chaw uas cov tshuaj tiv thaiv kab mob niaj hnub tsim thiab khaws cia. Cov tshuaj tiv thaiv no yuav tsum tau kawm ntawm no ntawm CERN lub chaw tab sis qhov kev hloov pauv ntawm magnetic teb tsim los ntawm lub accelerator ntawm qhov chaw txwv qhov tseeb ntawm kev ntsuas ntawm cov khoom antiproton. Yog li ntawd, qhov tseem ceeb ntawm kev thauj cov tshuaj tua kab mob uas tsim tawm ntawm AD mus rau lub chaw kuaj mob ntawm lwm qhov chaw. Tab sis antimatter tsis yog ib qho yooj yim los daws nrog raws li lawv sai sai tshem tawm ntawm kev sib cuag nrog teeb meem. Tam sim no, tsis muaj cov cuab yeej tsim nyog los thauj cov tshuaj tiv thaiv kab mob mus rau cov chaw sim ntawm lwm qhov chaw rau cov kws tshawb fawb los ua cov kev tshawb fawb siab. BASE-STEP (Symmetry Tests in Experiments with Portable antiprotons) yog ib kauj ruam rau pem hauv ntej ntawm no.
BASE-STEP yog ib qho khoom siv me me uas tsim los khaws thiab thauj cov tshuaj tiv thaiv kab mob los ntawm CERN qhov chaw mus rau lub chaw soj nstuam ntawm lwm qhov chaw rau kev tshawb fawb siab ntawm antimatter. Nws yog ib txoj haujlwm me me ntawm BASE, hnyav txog ib tuj thiab yog li tsib npaug me dua qhov kev sim BSE thawj zaug.
Thaum Lub Kaum Hli 24, 2024, BASE-STEP tau ua ib qho kev ua haujlwm zoo ua qauv qhia siv cov cuab yeej cuab tam los ua qhov sawv ntsug rau cov tshuaj tiv thaiv. Nws thauj huab cua ntawm 70 protons hauv zos hauv lub tsheb thauj khoom. Qhov no yog thawj qhov piv txwv ntawm kev thauj mus los ntawm cov khoom xoob hauv cov cuab yeej rov qab siv tau thiab lub pob zeb tseem ceeb ntawm kev tsim cov kev pabcuam antiproton-xa mus rau kev sim ntawm lwm lub chaw kuaj mob. Nrog qee qhov kev ua kom zoo dua hauv cov txheej txheem, kev thauj mus los ntawm antiproton yog npaj rau xyoo 2025.
PUMA (antiProton Unstable Matter Annihilation) yog lwm qhov kev sim ntawm qhov zoo sib xws tab sis tsom rau lub hom phiaj sib txawv. Zoo li BASE-STEP, PUMA tseem koom nrog kev npaj cov cuab yeej thauj khoom kom txav cov tshuaj tiv thaiv los ntawm CERN's Antiproton Decelerator (AD) nrog rau nws qhov chaw ISOLDE rau kev siv hauv kev kawm txog kab txawv nuclear physics phenomena.
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References:
- CERN. Xov Xwm - BASE kev sim ua ib kauj ruam loj rau cov khoom txav tau yooj yim. Tshaj tawm 25 Lub Kaum Hli 2024. Muaj nyob ntawm https://home.cern/news/news/experiments/base-experiment-takes-big-step-towards-portable-antimatter
- CERN. Technical Design Report ntawm BASE-STEP. https://cds.cern.ch/record/2756508/files/SPSC-TDR-007.pdf
- Smorra C., et al 2023. BASE-STEP: Lub chaw thauj khoom antiproton thauj mus los rau kev tshawb fawb txog kev sib cuam tshuam. Rev. Sci. Instrum. 94, 113201. 16 Nov 2023. DOI: https://doi.org/10.1063/5.0155492
- Auman, T., Bartmann, W., Boine-Frankenheim, O. et al. PUMA, antiProton tsis ruaj tsis khov teeb meem kev puas tsuaj. Eur. Phys. J. A 58, 88 (2022). DOI: https://doi.org/10.1140/epja/s10050-022-00713-x
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Lwm yam khoom
- Vim li cas 'Qhov Teeb Meem' Dominates Lub Ntiaj Teb thiab tsis yog 'Antimatter'? Hauv Quest ntawm Vim Li Cas Ntiaj Teb Muaj (Lub Plaub Hlis 18, 2020)
- Unveiling Mystery of Matter-Antimatter Asymmetry of the Universe with Neutrino Oscillation Experiments (1 Lub Tsib Hlis 2020)
- Particle colliders rau kev kawm ntawm "Lub ntug thaum ntxov heev": Muon collider ua qauv qhia (31 Lub Kaum Hli 2024)
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 is the only facility where antiprotons are produced and stored. It is not possible to conduct high precision studies of antiprotons near AD due to magnetic field fluctuations generated by accelerators. Hence, transporting antiprotons from this facility to other laboratories is an imperative. At present, there is no suitable technology to do so. BASE-STEP is a step forward in this direction. It is a relatively compact device designed to store and transport antiprotons from CERN facility to laboratories at other locations for high precision studies of antimatter. On 24 October 2024, BASE-STEP conducted a successful technology demonstration using trapped protons as a stand-in for antiprotons. It transported a cloud of 70 protons locally in a truck. This was first instance of transportation of loose particles in a reusable trap and an important steppingstone towards creation of an antiproton-delivery service to experiments at other laboratories. With some refinements in procedures, antiprotons are planned to be transported in 2025.){kind=link}