resenhas e críticas NEUTRINOS EM TUDO QUE EU VEJO 5LFDUGR$YHOLQR*RPHV1 $OpPGRVFRQKHFLGRVUDLRVVRODUHVTXHVmRDSULQFLSDOIRQWHGHHQHUJLDGRQRVVR SODQHWDH[LVWHDOJRPDLVTXHpGHIRUPDLQLQWHUUXSWDHPLWLGRSHOR6ROHPQRVVD GLUHomR(PWRGDVDVGLUHo}HVpEHPYHUGDGH$QWHVTXHVHSRVVDSHUJXQWDUR que seria esse 'algo mais’UHVSRQGRVmRRVQHXWULQRV 8PFXULRVRIHQ{PHQRQRLQWHULRUGR6ROID]FRPTXHHPXP~QLFRVHJXQGR FHQWHQDVGHELOK}HVGHQHXWULQRVDWUDYHVVHPFDGDFHQWtPHWURTXDGUDGRGRVHX FRUSR(QTXDQWRSHQVDDHVVHUHVSHLWRWULOK}HVHWULOK}HVGHQHXWULQRVWHUmR DWUDYHVVDGRVHXFpUHEURHVHTXHUWHUiSHUFHELGRXPGHOHV(SRXFRLPSRUWDVH pGLDRXQRLWH(OHVDWUDYHVVDPD7HUUDFRPRVHHODQmRH[LVWLVVH$RPHLRGLD DWUDYHVVDPVXDFDEHoDGHFLPDSDUDEDL[RjPHLDQRLWHGHEDL[RSDUDFLPDH GXUDQWHRSRHQWHSRGHPOLWHUDOPHQWHHQWUDUSRUXPRXYLGRHVDLUSHORRXWUR 0DVRTXHUHDOPHQWHVmRHSRUTXHR6ROHPLWHQHXWULQRV"6mRSHULJRVRVSDUD DVD~GH"([LVWHDOJXPSURWHWRUGHQHXWULQRVWDOFRPRRVSURWHWRUHVVRODUHV" 6HVmRWDQWRVQHXWULQRVSRUTXHQmRFRQVHJXLPRVYHUDOJXQVGHOHV"3DUDHVVDV SHUJXQWDVDGHQWUHPRVRPXQGRGHPLVWpULRVTXHURQGDPRVQHXWULQRVHVVDV SDUWtFXODVIDQWDVPDV&RPHFHPRVSHORFRPHoR0HVPRSRUTXHHVWDPRVDSHQDV QRLQtFLRGDVGHVFREHUWDV 2V QHXWULQRV VmR SDUWtFXODV HOHPHQWDUHV TXH QmR WrP FDUJD HOpWULFD VmR QHXWURV3RU¶elementar’TXHURGL]HUTXHRVQHXWULQRVQmRWrPXPDVXEHVWUXWXUD QmRVmRIRUPDGRVSRUSDUWtFXODVDLQGDPHQRUHV6mRHOHPHQWDUHVWDOFRPRRV Revista UFG / Julho 2012 / Ano XIII nº 12 1 Doutor em Física (UNICAMP/ FERMILAB). Professor do Instituto de Física da UFG, Pesquisador Colaborador do FERMILAB, EUA. E-mail: <[email protected]>. 245 resenhas e críticas . NEUTRINOS EM TUDO QUE EU VEJO HOpWURQVHRVTXDUNV(TXDQWRDRVFRQKHFLGRVSUyWRQVHQrXWURQV"(VWHVQmR VmR SDUWtFXODV UHDOPHQWH HOHPHQWDUHV SRU VHUHP FRQVWLWXtGRV SRU SDUWtFXODV PHQRUHVRVTXDUNVup e down9HMDQD)LJXUDRHVTXHPDGR0RGHOR3DGUmRGDV 3DUWtFXODV(OHPHQWDUHV ([LVWHPWUrVWLSRVGHQHXWULQRV&RPXPHQWHGL]HPRVTXHVmRWUrVVDERUHVDR LQYpVGHWLSRV6mRHOHVHOHWU{QLFRPX{QLFRHWDX{QLFR2VFKDPDPRVSRUWDQWRGH QHXWULQRHOHWU{QLFRQHXWULQRPX{QLFRHQHXWULQRWDX{QLFR)LJXUD3RGHUtDPRV DGRWDUXPDQRYDGHÀQLomRHPTXHRVVDERUHVVHULDPPDUDFXMiODUDQMDHDoDt Figura 1: Partículas Elementares no Modelo Padrão. Fonte: FERMILAB (http://www.fnal.gov). 246 Revista UFG / Julho 2012 / Ano XIII nº 12 NEUTRINOS EM TUDO QUE EU VEJO . resenhas e críticas 6HP G~YLGD D QRPHQFODWXUD FRQYHQFLRQDO GRV QHXWULQRV TXDQWR DRV VHXV VDERUHVWHPXPDUD]mRGHVHU4XDQGRRVQHXWULQRVLQWHUDJHPFRPDPDWpULD PHVPRTXHLVVRDFRQWHoDPXLWRUDUDPHQWHRUHVXOWDGRGDLQWHUDomRQRVLQIRUPD RVDERUGRQHXWULQR6HGDLQWHUDomRWLYHUPRVFRPRUHVXOWDGRXPHOpWURQGL]HPRVTXHVHWUDWDYDGHXPQHXWULQRHOHWU{QLFRVHWLYHUPRVXPP~RQGL]HPRV QHXWULQRPX{QLFR(VWDpXPDVLWXDomRDGHTXDGDSDUDRIDPRVR´Diga-me com quem tu andas, que eu te direi quem tu ésµ1RFDVRHPTXHVWmRVHWXDQGDVFRP RHOpWURQWXpVXPQHXWULQRHOHWU{QLFR $WpSRXFRWHPSRDFUHGLWDYDVHTXHRVQHXWULQRVQmRWHULDPPDVVD6LPXPD SDUWtFXODSRGHWHUPDVVD]HURpRFDVRGRIyWRQDSDUWtFXODGHOX](QWUHWDQWR UHFHQWHPHQWH D )tVLFD GH 3DUWtFXODV GHVFREULX TXH RV QHXWULQRV WrP PDVVD PHVPRTXHPXLWRSHTXHQD(VVDGHVFREHUWDPXGDRTXHSHQViYDPRVVREUHRV QHXWULQRVHWHPLPSOLFDo}HVQD&RVPRORJLD $PDVVDGLIHUHQWHGH]HURGRVQHXWULQRVpFRQVHTXrQFLDGRIDWRGHREVHUYDUPRVXPDPXGDQoDa prioriWLGDFRPRSURLELGDQRVDERUGRVQHXWULQRV3RU PXGDQoD QR VDERU HQWHQGDPRV SRU H[HPSOR TXH XP QHXWULQR PDUDFXMi VH WUDQVIRUPDHPXPQHXWULQRODUDQMDGHSRLVHPQHXWULQRDoDtHSRGHUHWRUQDUD QHXWULQRPDUDFXMi,VVRQmRGHYHULDVHUSRVVtYHOPDVDFRQWHFH)DWRTXHQRVOHYRX DDSULPRUDUDWHRULDSDGUmRGD)tVLFDGH3DUWtFXODV&XULRVRRFRPSRUWDPHQWR GRVQHXWULQRVVRIUHPGHXPWLSRGHPXGDQoDGHSHUVRQDOLGDGH(QmRHVWDPRV IDODQGR GH GXSOD SHUVRQDOLGDGH PDV GH WULSOD SHUVRQDOLGDGH 3DUD R FDVR GH GHVFREULUPRVPDLVVDERUHVIDOHPRVHPP~OWLSODSHUVRQDOLGDGH 2PRGHORWHyULFRTXHPHOKRUH[SOLFDRVUHVXOWDGRVH[SHULPHQWDLVGHPXGDQoD de sabor, é o modelo de oscilação de neutrinos, que tem como ideia seminal uma SURSRVWDGHGRItVLFRLWDOLDQR%UXQR3RQWHFRUYR7DLVUHVXOWDGRVjOX]GHVVH PRGHORVXJHUHPTXHH[LVWHXPDGLIHUHQoDGHPDVVDHQWUHRVGLIHUHQWHVVDERUHV GHQHXWULQRV9$/',9,(662H*8==21mRVHVDEHDLQGDTXHPpPDLV SHVDGRTXHTXHP$KLHUDUTXLDGHPDVVDpXPSUREOHPDHPDEHUWRSDUDVHU UHVROYLGRQRVSUy[LPRVDQRV 6DEHPRVWDPEpPTXHDOpPGRVQHXWULQRVH[LVWHPRVDQWLQHXWULQRVTXHVmR DVDQWLSDUWtFXODVGRVQHXWULQRV(VVHIDWRpFRQVHTXrQFLDGHUHVXOWDGRVH[SHULPHQWDLVPDVDLQGDH[LVWHPHVSHFXODo}HVVREUHDGLVWLQomRHQWUHQHXWULQRVH DQWLQHXWULQRV7DOFRPRRVQHXWULQRVRVDQWLQHXWULQRVWDPEpPWrPWUrVVDERUHV ²DQWLQHXWULQRHOHWU{QLFRDQWLQHXWULQRPX{QLFRHDQWLQHXWULQRWDX{QLFR Revista UFG / Julho 2012 / Ano XIII nº 12 247 resenhas e críticas . 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NEUTRINOS EM TUDO QUE EU VEJO $WpPHVPRQRVVRFRUSRTXHFRQWpPFHUWDTXDQWLGDGHGH SRWiVVLRUDGLRDWLYRHPLWHPLOK}HVHPLOK}HVGHQHXWULQRVSRU GLD0DVQmRSRGHPRVXVDUXPDIRQWHTXDOTXHUSDUDGHWHFWDU RV QHXWULQRV ² HODV SUHFLVDP VHU PXLWR LQWHQVDV RX VHMD R Q~PHURGHQHXWULQRVGHYHVHUJUDQGHPXLWRPDLRUTXHRTXH YRFrHPLWHSRUGLD9HMDPRVDOJXPDVGDVIRQWHVYLiYHLVSDUD VHUHPXVDGDVHPH[SHULPHQWRVFRQVWUXtGRVDTXLQD7HUUD 2Vneutrinos solaresVmRSURGX]LGRVQRSURFHVVRGHFRPEXVWmRQRQ~FOHRGR6ROTXHHQYROYHDIXVmRGHKLGURJrQLR FRQYHUWHQGRR HP KpOLR (VVHV QHXWULQRV HVFDSDP GR VHX LQWHULRUHYLDMDPSUDWLFDPHQWHjYHORFLGDGHGDOX]HPWRGDV DV GLUHo}HV GR HVSDoR 2XWUDV HVWUHODV SURGX]HP QHXWULQRV SHORPHVPRSURFHVVRRXSHORFKDPDGRFLFOR&12FDUERQR QLWURJrQLR H R[LJrQLR TXH HQYROYH HVVHV HOHPHQWRV FRPR FDWDOLVDGRUHVQRSURFHVVRGHFRPEXVWmR 2Vneutrinos atmosféricosVmRSURGX]LGRVSRUUDLRVFyVPLFRV TXHVmRSDUWtFXODVGHVGHSUyWRQVDWpQ~FOHRVGRiWRPRGH IHUURTXHYLDMDPSHOR8QLYHUVRHSRGHPFROLGLUFRPQRVVD DWPRVIHUD 'HVWD FROLVmR VmR SURGX]LGDV YiULDV SDUWtFXODV VHFXQGiULDVTXHFROLGHPFRPRXWUDVSDUWtFXODVGDDWPRVIHUD RXVRIUHPGHFDLPHQWRHDVVLPSRUGLDQWH&RPRUHVXOWDGRVmR IRUPDGRVRTXHFKDPDPRVGHchuveiros atmosféricos extensos *20(6 FRPSRVWRV HP JUDQGH SDUWH SRU QHXWULQRV )LJXUD 2VUHDWRUHVQXFOHDUHVGHQWURGDVXVLQDVWDOFRPRRVGD XVLQDGH$QJUDQR5LRGH-DQHLURWDPEpPSURGX]HPTXDQWLGDGHVVLJQLÀFDWLYDVGHQHXWULQRVUHVXOWDQWHVGRSURFHVVRGH ÀVVmRGRQ~FOHRUDGLRDWLYR1DXVLQDGH$QJUDIRLFRQVWUXtGRXP GHWHFWRUGHQHXWULQRVEUDVLOHLURTXHHVWiHPIXQFLRQDPHQWR 2V DFHOHUDGRUHV GH SDUWtFXODV VmR FDSD]HV GH SURGX]LU IHL[HVPXLWRLQWHQVRVGHQHXWULQRVFRPRID]XPGRVJUDQGHV ODERUDWyULRVGH)tVLFDGH3DUWtFXODVGRPXQGRR)(50,/$% Fermi National Accelerator Laboratory HP &KLFDJR 8P GRV H[SHULPHQWRV GHVVH ODERUDWyULR p R 0,126 Main Injector 250 Revista UFG / Julho 2012 / Ano XIII nº 12 NEUTRINOS EM TUDO QUE EU VEJO Neutrino Oscillation SearchTXHUHDOL]RXPHGLGDVSUHFLVDV TXHFRPSURYDUDPRPRGHORGHRVFLODomRGHQHXWULQRV *20(6 (FRPRID]HUSDUDGHWHFWDURVQHXWULQRV"6mRQHFHVViULRVGHWHFWRUHVH[WUHPDPHQWHJUDQGHVSRUYH]HVFRP PLOKDUHVGHWRQHODGDVIRUPDGRVSRUGLIHUHQWHVPDWHULDLV 0XLWRVGHOHVÀFDPVXEWHUUkQHRVWDOFRPRRVGHWHFWRUHV GR0,126²XPGHOHVÀFDDPHWURVGHSURIXQGLGDGH HPXPDPLQDGHIHUUR(WDPEpPpSUHFLVRHVSHUDUSRU ORQJRVSHUtRGRVDWpTXHXPGRVQHXWULQRVLQWHUDMDFRP RGHWHFWRU&RPRDSUREDELOLGDGHGHLQWHUDomRpPXLWR SHTXHQD DOJXQV H[SHULPHQWRV REVHUYDP DSHQDV XPD GH]HQDGHQHXWULQRVHPXPDQRLQWHLURGHWUDEDOKR e MXVWDPHQWH SHOR IDWR GD LQWHUDomR GRV QHXWULQRV FRPDPDWpULDVHUPXLWRUDUDHWDPEpPSRUVHUPXLWR IUDFD TXH SRGHPRV ÀFDU WUDQTXLORV RV QHXWULQRV QmR ID]HP PDO j VD~GH$R ORQJR GH XPD YLGD FHUFD GH PHLDG~]LDGHQHXWULQRVLQWHUDJLUmRHPXPDSHVVRD( FRPRUHVXOWDGRGHXPDGHVVDVLQWHUDo}HVXPHOpWURQ VHUi SURGX]LGR VHP PDLRUHV FRQVHTXrQFLDV$OpP GR PDLVSRGHPRVSHQVDUTXHDYLGDIRLGHVHQYROYLGDQXP FRQWH[WRHPTXHRVQHXWULQRVMiHVWDYDPSUHVHQWHV'H IDWRRVQHXWULQRVHVWmRPXLWRPDLVSUHVHQWHVGRTXH VHSRGHULDLPDJLQDU1mRKiVHTXHUXPOXJDUHPWRGR 8QLYHUVRTXHQmRHVWHMDUHSOHWRGHQHXWULQRV2OKRDR PHXUHGRUHPHVPRQmRRVHQ[HUJDQGRRVQHXWULQRV HVWmRHPWXGRTXHHXYHMR . resenhas e críticas Figura 2: Esquema de um Chuveiro Atmosférico Extenso gerado por raio cósmico. Referências GOMES, R. A. Olhando o Céu do Fundo de um Poço. Revista UFG, n. 08, 2010. VALDIVIESSO, G. A. e GUZZO, M. M. Compreendendo a Oscilação dos Neutrinos. Rev. Bras. Ens. Fís., v. 27, n. 4, 2005. Revista UFG / Julho 2012 / Ano XIII nº 12 Fonte: CERN (http://www.cern.ch). 251