Particle Physics 3+< ' $FRVWD

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1 Particle Physics 3+< ' $FRVWD

2 Particle Physics 7KLV ILHOG LV DERXW WKH VWXG\ RI IRUFHV DQG SDUWLFOHV %XW IRUFHV DQG SDUWLFOHV DUH HTXLYDOHQW ² 5HFDOO WKDW WKH HOHFWURPDJQHWLF ILHOG LV TXDQWL]HG LQWR SKRWRQV,Q JHQHUDO WKH ILHOGVµ FRUUHVSRQGLQJ WR DOO IXQGDPHQWDO IRUFHV DUH TXDQWL]HG LQWR SDUWLFOHV 0RUHRYHU WKHVH ILHOGV SDUWLFOHV REH\ FHUWDLQ FRQVHUYDWLRQ ODZV ZKLFK DULVH IURP V\PPHWULHV LQ QDWXUH 3DUWLFOH SK\VLFV DWWHPSWV WR XQGHUVWDQG QDWXUH DW LWV PRVW IXQGDPHQWDO OHYHO WR H[SODLQ SK\VLFDO SKHQRPHQD LQ WHUPV WKH VPDOOHVW VHW RI FRQVHUYDWLRQ ODZV DQG V\PPHWULHV %XW VXSHUILFLDOO\ LW RIWHQ VHHPV OLNH SDUWLFOH SK\VLFV LV OLNH ]RRORJ\ 4/14/00 PHY D. Acosta 2

3 Beginning of Nuclear Substructure (OHPHQWV RI WKH VDPH JURXS KDYH QHDUO\ WKH VDPH FKHPLFDO SURSHUW\ &KHPLFDO SHULRGLFLW\ GHSHQGV RQ WKH DWRPLF QXPEHU = $OO HOHPHQWV FRPSRVHG RI MXVW HOHFWURQV QHXWURQV DQG SURWRQV $Q\ RWKHU IXQGDPHQWDO SDUWLFOHV" 4/14/00 PHY D. Acosta 3

4 The Particle Zoo 'LVFRYHUHG LQ FRVPLF UD\V ² 3RVLWURQ 0 0H9 DQWLHOHFWURQ SUHGLFWHG E\ 'LUDF (TQ ² 0XRQ 0 0H9 ² 3LRQ 0 0H9 SUHGLFWHG E\ <XNDZD WR FDUU\ VWURQJ IRUFH 0H9 HQHUJ\ HOHFWURQ JDLQV ZKHQ DFFHOHUDWHG DFURVV PLOOLRQ YROWV 'LVFRYHUHG LQ SDUWLFOH DFFHOHUDWRUV E\ ².DRQ UKR RPHJD «0HVRQV OLNH SLRQ ² /DPEGD 6LJPD ;L «%DU\RQV OLNH SURWRQ 0HVRQV DQG %DU\RQV IHHO WKH VWURQJ QXFOHDU IRUFH /HSWRQV HOHFWURQ PXRQ GR QRW 4/14/00 PHY D. Acosta 4

5 Classification +DGURQV ² 3DUWLFOHV WKDW FDUU\ QXFOHDU FKDUJHµ DQG LQWHUDFW ZLWK WKH 6WURQJ 1XFOHDU )RUFH ² 0HVRQV,QWHJHU VSLQ ERVRQV V «π.ρ ω «² %DU\RQV +DOILQWHJHU VSLQ IHUPLRQV V «S Q Λ «/HSWRQV ² 3DUWLFOHV WKDW GR QRW FDUU\ DQ\ QXFOHDU FKDUJHµ DQG GR QRW LQWHUDFW ZLWK WKH 6WURQJ 1XFOHDU )RUFH HOHFWURQV PXRQV WDXV QHXWULQRV«² 'R QRW ELQG LQ QXFOHXV %RWK FODVVHV RI SDUWLFOHV FDQ LQWHUDFW YLD WKH (OHFWURPDJQHWLF IRUFH LI WKH\ KDYH FKDUJH DQG GHFD\ YLD WKH :HDN 1XFOHDU )RUFH 4/14/00 PHY D. Acosta 5

6 Conservation Laws (QHUJ\ DQG 0RPHQWXP ² &RQVHUYHG,Q SDUWLFXODU 6SHFLDO 5HODWLYLW\ DSSOLHV 0 0 ² ([DPSOH π γ γ but not π γ + + e e γ γ but not e e γ (OHFWULF FKDUJH ² &RQVHUYHG 0XVW DGG XS WR WKH VDPH FKDUJH RQ HDFK VLGH RI WKH HTXDWLRQ %DU\RQ 1XPEHU ² &RQVHUYHG %DU\RQ &KDUJHµ PXVW DGG XS WR VDPH YDOXH RQ HDFK VLGH RI WKH HTXDWLRQ + ++ p + π B: 1+ 0= 1 /HSWRQ 1XPEHU ² &RQVHUYHG /HSWRQ &KDUJHµ PXVW DGG XS WR VDPH YDOXH RQ HDFK VLGH RI WKH HTXDWLRQ IRU HDFK W\SH RI OHSWRQ HOHFWURQ PXRQ WDX µ e + νe + ν µ Le : 0= L : 1= µ 1RWH DQWLSDUWLFOHV KDYH WKH RSSRVLWH FKDUJHµ RI SDUWLFOHV HOHFWULF FKDUJH EDU\RQ QXPEHU OHSWRQ QXPEHU 4/14/00 PHY D. Acosta 6

7 Lifetime of Particles )DVWHVW GHFD\V LQYROYH WKH 6WURQJ 1XFOHDU )RUFH ² τ V ² ([DPSOH ++ p + π + ² &RPSDUH WR WKH WLPH LW WDNHV OLJKW WR FURVV IP m 24 t = = 3 10 s m/s 1H[W IDVWHVW GHFD\V LQYROYH WKH (OHFWURPDJQHWLF )RUFH ² τ V ² ([DPSOH π 0 γ γ 6ORZHVW GHFD\V LQYROYH WKH :HDN 1XFOHDU )RUFH ² τ V ² ([DPSOH K π π π K µ + ν µ,i D FRQVHUYDWLRQ ODZ IRUELGV D W\SH RI GHFD\ WKHQ WKH OLIHWLPH ZLOO EH VLJQLILFDQWO\ ORQJHU 4/14/00 PHY D. Acosta 7

8 Strangeness 6RPH SDUWLFOHV DUH REVHUYHG WR GHFD\ UDSLGO\ RWKHUV DUH QRW ² :K\ GRHVQ W.DRQ GHFD\ TXLFNO\ OLNH RWKHU VWURQJ QXFOHDU GHFD\V" K π π π 0XUUD\ *HOO0DQQ DQG.D]XKLNR 1LVKLMLPD LQYRNH QHZ TXDQWXP QXPEHU FDOOHG VWUDQJHQHVVµ ZKLFK LV FRQVHUYHG LQ HOHFWURPDJQHWLF DQG VWURQJ QXFOHDU LQWHUDFWLRQV EXW LV YLRODWHG E\ WKH ZHDN QXFOHDU LQWHUDFWLRQ.DRQ /DPEGD 6LJPD KDYH VWUDQJHQHVV 3LRQ 3URWRQ 1HXWURQ KDYH VWUDQJHQHVV 4/14/00 PHY D. Acosta 8

9 The Eightfold Way 'HYHORSHG E\ 0XUUD\ *HOO0DQQ DQG <XYDO 1H HPDQ LQ 3ORW K\SHUFKDUJH < EDU\RQ QXPEHU VWUDQJHQHVV YHUVXV LVRVSLQ 2EVHUYH SDWWHUQV LQ PXOWLSOHWV 2PHJD SUHGLFWHG DQG REVHUYHG Charge Isospin Periodic table for elementary particles! 4/14/00 PHY D. Acosta 9

10 Quarks 0XUUD\ *HOO0DQQ DQG *HRUJH =ZHLJ SURSRVH LQ WKDW PHVRQV DQG EDU\RQV DUH QRW HOHPHQWDU\ EXW DUH FRPSRVHG RI VPDOOHU FRQVWLWXHQWV 4XDUNV -DPHV -R\FH )LQQHJDQ V :DNH 7KUHH TXDUNV IRU 0XVWHU 0DUNµ X G DQG V TXDUNV XS GRZQ VWUDQJH 7KHVH TXDUNV KDYH VSLQ DQG KDYH IUDFWLRQDO HOHFWULF FKDUJH 3URWRQ X X G 1HXWURQ XGG 3LRQ XG XX GG GX.DRQ XV GV VG VX 1RW FOHDU LI WKLV LV D PDWKHPDWLFDO FRQYHQLHQFH RU UHDOLW\ 4/14/00 PHY D. Acosta 10

11 Rutherford Scattering Experiments by Geiger & Marsden in /14/00 PHY D. Acosta 11

12 Rutherford Model of the Atom Conclusion: the atom contains a positive nucleus < 10 fm in size (1 fm = m) 4/14/00 PHY D. Acosta 12

13 How we see particles The smaller the wavelength, the smaller the features observed. Recall that the deboglie wavelength of a particle is λ = h / p So we need high energies to probe quarks 4/14/00 PHY D. Acosta 13

14 Particle Accelerators 4/14/00 PHY D. Acosta 14

15 Size of Nuclei 5REHUW +RIVWDGWHU SHUIRUPV H[SHULPHQW DW 6WDQIRUG XVLQJ QHZ OLQHDU DFFHOHUDWRU IRU HOHFWURQV LQ V ( 0H9 λ IP 7KH SURWRQ LV QRW D SRLQW 'HYLDWLRQ RI HODVWLF VFDWWHULQJ UDWH IURP 5XWKHUIRUG 6FDWWHULQJ 3URWRQ DQG QXFOHL KDYH H[WHQGHG FKDUJH GLVWULEXWLRQV 1REHO SUL]H LQ proton 4/14/00 PHY D. Acosta 15

16 Deep Inelastic Scattering 6WDQIRUG /LQHDU $FFHOHUDWRU &HQWHU 6/$& FRQVWUXFWV PLOH ORQJ DFFHOHUDWRU LQ ( *H9 ([SHULPHQW E\ 6/$& DQG 0,7 )ULHGPDQ.HQGDOO 7D\ORU 1REHO LQ FUDFNV WKH SURWRQ LQHODVWLF VFDWWHULQJ LQ 6XUSULVH ZKHQ VFDWWHULQJ UDWH IROORZV 5XWKHUIRUG IRUPXOD IRU VFDWWHULQJ EHWZHHQ SRLQW SDUWLFOHV 5LFKDUG )H\QPDQ GXEV SURWRQ FRQVLWXHQWV SDUWRQV 4XDUNV DUH UHDO e p 4/14/00 PHY D. Acosta 16

17 Quarks within the Proton 6FDWWHULQJ UDWH LV LQGHSHQGHQW RI UHVROYLQJ SRZHU RI LQFRPLQJ HOHFWURQ ² 4XDUN DUH IXQGDPHQWDO %MRUNHQ 6FDOLQJ 7RWDO VFDWWHULQJ UDWH FRQVLVWHQW ZLWK VSLQ TXDUNV ² &DOODQ*URVV UHODWLRQ %XW PRPHQWXP IUDFWLRQ FDUULHG E\ D TXDUN LV QRW 4/14/00 PHY D. Acosta 17

18 Proton is a Complicated Object 7RWDO PRPHQWXP IUDFWLRQ FDUULHG E\ TXDUNV LV RQO\ 5HVW LV FDUULHG E\ JOXRQV WKH FDUULHUV RI WKH VWURQJ QXFOHDU IRUFH 7RWDO VSLQ FDUULHG E\ YDOHQFH TXDUNV XXG LV DOVR QRW 4/14/00 PHY D. Acosta 18

19 November Revolution 1HZ TXDUN GLVFRYHUHG LQ FKDUP 6DP 7LQJ OHDGV GLVFRYHU\ RI D UHVRQDQFH LQ SURWRQQXFOHRQ FROOLVLRQV DW %URRNKDYHQ 1DWLRQDO /DERUDWRU\ FDOOV LW WKH - SDUWLFOH %XUW 5LFKWHU OHDGV GLVFRYHU\ RI D UHVRQDQFH DW DQ H H FROOLGHU DW 6/$& FDOOV LW WKH 3VL SDUWLFOH 0DVV RI -ψ LV *H9 5LFKWHU 7LQJ VKDUH 1REHO SUL]H ([DPSOH RI FKDUPRQLXP ² %RXQG VWDWH RI F F ² /LNH SRVLWURQLXP H H EXW IRU VWURQJ IRUFH ²,Q RWKHU ZRUGV OLNH + DWRP +LJKHU PDVV H[FLWHG VWDWHV H[LVW DOVR OLNH ψ 4/14/00 PHY D. Acosta 19

20 The Bottom Quark,Q /HRQ /HGHUPDQ OHDGV GLVFRYHU\ RI D KLJKHU PDVV UHVRQDQFH DW )HUPLODE 0DVV RI Υ 8SVLORQ LV *H9 ([DPSOH RI ERWWRPRQLXP E E $JDLQ H[FLWHG VWDWH UHVRQDQFHV H[LVW 1RZ VWXGLHG LQ JUHDW GHWDLO LQ H H FROOLGHU H[SHULPHQWV ² &/(2 VWXGLHV % PHVRQV E TXDUN XGVF 6RRQ WKHUH ZLOO EH D URXQG RI PDQ\ QHZ H[SHULPHQWV GRLQJ % SK\VLFV 4/14/00 PHY D. Acosta 20

21 Discovery of the top quark The top quark was discovered in 1995 with a mass of 175 GeV, as much as an atom of gold! 4/14/00 PHY D. Acosta 21

22 CDF and DØ 4/14/00 PHY D. Acosta 22

23 Particle Physics Detectors 4/14/00 PHY D. Acosta 23

24 History of the Discovery of Quarks 6/$& ² 'LVFRYHU\ RI TXDUNV LQ HOHFWURQSURWRQ VFDWWHULQJ 6/$& DQG %URRNKDYHQ ² 'LVFRYHU\ RI WKH FKDUP TXDUN LQ HOHFWURQ SRVLWURQ DQQLKLODWLRQ )HUPLODE ² 'LVFRYHU\ RI WKH ERWWRP TXDUN LQ SURWRQ FROOLVLRQV )HUPLODE ² 'LVFRYHU\ RI WKH WRS TXDUN LQ SURWRQ DQWLSURWRQ DQQLKLOLDWLRQ 4/14/00 PHY D. Acosta 24

25 4/14/00 PHY D. Acosta 25

26 4/14/00 PHY D. Acosta 26

27 The Standard Model of Particle Physics 4/14/00 PHY D. Acosta 27

28 Jets 'HVSLWH DOO WKLV HYLGHQFH QR RQH KDV DFWXDOO\ VHHQ D VLQJOH EDUH TXDUN,QVWHDG ZH REVHUYH FOXVWHUV RI NQRZQ SDUWLFOHV -HWV ZKLFK WUDYHO LQ WKH GLUHFWLRQ RI WKH VFDWWHUHG TXDUN 7KHVH MHWV EHKDYH DV LI WKH\ RULJLQDWHG IURP D VSLQ TXDUN &DQQRW FDOFXODWH WKLV HIIHFW H[DFWO\ LQ WKHRU\ EHFDXVH VHULHV H[SDQVLRQ GRHV QRW FRQYHUJH π π π quark 4/14/00 PHY D. Acosta 28

29 Where s the Glue? 2QO\ LQGLUHFW HYLGHQFH IRU JOXRQV %XW PDQ\ FDOFXODWLRQV DUH FRQILUPHG E\ H[SHULPHQWDO PHDVXUHPHQWV *OXRQV FRXSOH WR WKH FRORUµ FKDUJHV RI TXDUNV UHG JUHHQ EOXH 6FDWWHULQJ UDWHV LQ H H FROOLGHUV VKRZ WKLV IDFWRU RI 4/14/00 PHY D. Acosta 29

30 4/14/00 PHY D. Acosta 30

31 Do Quarks have Substructure? 1H[W JHQHUDWLRQ RI 'HHS,QHODVWLF 6FDWWHULQJ H[SHULPHQWV LQ +DPEXUJ *HUPDQ\ +(5$ :RUOG V RQO\ HOHFWURQSURWRQ &ROOLGHU 6SDWLDO UHVROXWLRQ LV P ([WHQGV UHDFK E\ VHYHUDO RUGHUV RI PDJQLWXGH RYHU IL[HGWDUJHW H[SHULPHQWV 4/14/00 PHY D. Acosta 31

32 European Center for Nuclear Research (CERN) 4/14/00 PHY D. Acosta 32

33 CERN Particle Accelerators 4/14/00 PHY D. Acosta 33

34 4/14/00 PHY D. Acosta 34

35 4/14/00 PHY D. Acosta 35

36 4/14/00 PHY D. Acosta 36