Historical Overview
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Historical Overview Humorous Memories CERN Neutrino Experiment (1970-1979) Ray Davis Experiment IMB and Kamiokande Experiments Super-Kamiokande SNO Prof. Tegid Wyn Jones (UCL) CERN Neutrino Beam - 1971 2 CERN Neutrino Horn 3 2 2 Q2 = qQ2 = q − − 2 2 Q = q 2 2 Q Q−x = x = 2p q 2pQ2q · x = · p q 2pp qyq= · y = ·· p k p k · p· q y = · 2 2 p Qk = sxy Q = sxy· 2 Q = sxys =(p + k)2 s =(p + k)2 2 s =(F~p=+qk)E~ + ~v B~ F~ = q E~ + ~v B~ ⇥ • In the target ⇣⇥ ⌘ Vud VF~us= q⇣VubE~ + ~v B~⌘0.974 0.225 0.00351 + |+ ||- - || | V•udpi , KVusV, pi , VKubV productionV 0.974=⇥ 0.225 0.225 0 0.973.00351 0.0412 | ||0| cd||||cs| ||⇣cb|1 0 ⌘ 1 Vcd(sameVcsV processestd VVcbts = Voccurtb 0.225 in the0.00867 0 atmosphere-.973 0.0404 0.0412 0Arnold.999 0|Vud||V|us||||Vub|1||0| 0.974 0.225 0.003511 |VtdWolfendale||@Vts ||V tbet| al. were0A.00867 the@ first 0.0404 to calculate 0.999 neutrinoA |Vcd||Vcs||Vcb|F (x=)=x0.225e2 (q 0(.x973)+q ( 0x.0412)) @0| fluxes)|| || |A12 @0 qi i i A1 Vtd VtsF (x)=Vtb x e20.(00867q i(x)+ 0q.0404(x)) 0.999 | || ||2 | qi Xi i @ A @ A i 2 + + F (x)=xX e (⇡q (x)+µ q⌫µ(x)) • Neutrino2 horn focusesqi positivei ! i or negative particles +i + ⇡X µ ⌫µ • Decay path ! + + + K+ µ ⌫µ ⇡ µ ⌫µ! + ! + K µ ⌫µ ! + + + µ + ⌫µe ⌫e K µ ⌫!µ • Iron shield + ! + µ e ⌫e • Muons stop in shield! and are +used to determine + ⌫l ++n H + l− µ e ⌫e! neutrino spectrum ! + ⌫l + n H + l− 4 ++ • Gargamelle !⌫ + p H + l− l + ⌫l + n H !+ l− ! ++ ⌫ + p H + l− l 0 !⌫l + n H + ⌫l ++ ! ⌫l + p H + l− ! 0 ⌫l + n H + ⌫l + !⌫l + p H + ⌫l 0 ! ⌫l + n H + ⌫l ! + ⌫l + p H + ⌫l + !⌫e + p n + e + ! ⌫l + p H + ⌫l ! + ⌫e + p n + e + !⌫e + p n + e !+ ⌫e + p n + e ! + ⌫e + p ⌫ n++ne p + e− !e ! ⌫ + p n + e+ e ! ⌫e + n p + e−8 ! ⌫e + n p + e− !8 8 Gargamelle 5 Q2 = q2 − Q2 =Q2q2 x = − 2p q · 2 Q2 2 QQx2===p qq2q y = 2p· −q p −k· p· q 2 y2 = Q·Q2 xQx=== psxyk 22p·p qq Q2 = sxy· · s =(p +ppkq)2q yy== · · pp kk2 s =(p +· k) F~ = q E~ + ~v· B~ Q22= sxy⇥ F~ = Qq⇣ E~=+sxy~v B~⌘ V V V 0.974⇥ 0.225 0.00351 | ud||us||ub| ⇣ ⌘ Vcd Vcs Vcb = 0.2252 0.973 0.0412 Vud Vus Vub s =(p +0.974k) 2 0.225 0.00351 0| | |||||||||1| 0 1 VtdV VtsV VtbV s =(= 0p.008670+.225k) 0 0..0404973 0 0.0412.999 |0| ||cd||||cs||cb| |1 0 1 @ Vtd Vts VtbA @ 0.00867 0.0404 0.999 A | ||F (||x)=x| e2 (q (x)+q (x)) @ 2 F~ =Aq E~@qi+ ~iv B~ i A F (xF)=~ =x qi eE~2 +(q ~(v⇥x)+B~q (x)) 2 X qi i i ⇣i ⇥ ⌘ +X + V V V ⇡ ⇣ µ0.⌫974µ ⌘ 0.225 0.00351 ud us ub +! + |V ||V ||V | ⇡ µ0⌫.974µ 0.225 0.00351 Vudcd Vuscs Vcbub = ! 0.225 0.973 0.0412 0|| |||| |||| ||1 + 0 + 1 VVcdtd VVcsts VVtbcb K = 0µ.008670⌫.225µ 0.0404 0.973 0. 0999.0412 0|| |||| ||||||1 +!0 + 1 @ Vtd Vts Vtb AK @ 0µ.00867⌫µ 0.0404 0.999A | || ||| !2 @ F2(x)=xA + e@q +(qi(x)+qi(x)) A µ i2e ⌫e GargamelleF (x)=x µi +!e e+(⌫q (x)+q (x)) 2 X !qi ei i i • Charged current events+ ++ ⌫l +⇡Xn Hµ +⌫+µl− ⌫l + n! H + l− +!! + ⇡ µ ⌫µ !++ ⌫l + p+ H +++ + l− ⌫ K+ p Hµ ⌫+µ l− l !! +! + • Discovery of the weakK neutralµ ⌫µ current (1973) ⌫ + n !H0 + ⌫+ l⌫eµ++ p! en++⌫ e l !! e + + µ +e ⌫+ ⌫l⌫++p p Hn ++e⌫el e ! +/0 ⌫ + n(p) !!H + l− • Processes that can be! used to detect astrophysical + neutrinos ⌫⌫e++pn np+++ee/−0 ⌫ + en(p)!! H + l− ⌫ + p ! n + e+ e ! ⌫⌫ ++ ep− n⌫++ee+− If this occurs in a ⌫nucleuse + p!! nthen+ e +there are threshold e ! effects 37 37 ⌫e + Cl17 Ar18 + e− ⌫e + n !p + e− ! ⌫ + e− ⌫ + e− 8! 8 6 8 8 Ray Davis Experiment 7 Q2 = q2 − 2 2 Q2 Q = x q= − 2p q · Q2 p q x = y = · 2p q p k · · p q y = Q· 2 = sxy p k · 2 Q2 =ssxy=(p + k) F~ = q E~2 + ~v B~ s =(p + k) ⇥ ⇣ ⌘ V V V 0.974 0.225 0.00351 | ud||usF~||= q ubE~| + ~v B~ Vcd Vcs Vcb = ⇥ 0.225 0.973 0.0412 0|V ||V ||V⇣ |1 00.00867⌘ 0.0404 0.999 1 | td||ts||tb| Vud @ Vus Vub A0.974@ 0.225 0.00351 A | || || | 2 V V V F2(x)== x 0.225e (qi( 0x.973)+q (x 0)).0412 0| cd||cs||cb|1 0 qi i 1 V V V 0.00867i 0.0404 0.999 | td||ts||tb| X @ A @ + + A 2⇡ µ ⌫µ F2(x)=x eqi (qi!(x)+qi(x)) i X K+ µ+⌫ ⇡+ µ+⌫! µ ! µ + + µ e ⌫e K+ µ+⌫! ! µ +/0 ⌫ + n(p) H + l− µ+ e+⌫! ! e + ⌫e + p n + e +/0 ⌫ + n(p) H !+ l− ! + ⌫e + p n + e ⌫ + p n +!e+ Ray Davis Experimente ! (1968-1994) 3 ⌫ + n p + e− • 380 m of dry cleaninge fluid,! containing chlorine at ⌫ + n p + e− 1400m deep in eHomestake! Mine • Every few weeks Davis⌫ + ebubbled− ⌫ + ehelium− through the ! tank to get out⌫ Argon+ e− ⌫ + e− ! 8 37 37 • Sensitive to B neutrinos⌫e + Cl17 (highAr 18energy)+ e− 37 37! ⌫ + Cl Ar + e− e 17 ! 18 37 37 e− + Ar18 ⌫e + Cl17 + γ(2.85kev) 37 ! 37 e− + Ar ⌫ + Cl +2.85kevγ • Discovered the18 so! callede 17solar neutrino deficit based on the calculations of John8 Bahcall 71 71 • Effect confirmedGa + by⌫e the GeGALLEX+ e− and SAGE ! experiments which were sensitive to the pp neutrinos 71 71 Ga + ⌫ Ge + e− 8 e ! 71 71 Ge + e− Ga + ⌫ ! e 8 ⌫ + d ⌫ + p + n ! n + d 3 H + γ(6.3MeV) ! n +35 Cl 36 Cl + γ(8.6MeV) ! 9 IMB Experiment 9 Kamiokande 10 IMB Kamiokande 10,000 tonnes (H2O) 3,000 tonnes (H2O) 3,000 tonnes fiducial ~1,000 tonnes fiducial volume volume 5” tubes with WLS 50” tubes plates • Neutrinos from SN1987A –07:35 GMT 23rd February 1987 in LMC –20 M⊙ blue giant collapse –170,000 light years (1.6 x 1018km) 11 Q2 = q2 − Q2 x = 2p q · p q y = · p k · Q2 = sxy s =(p + k)2 F~ = q E~ + ~v B~ ⇥ ⇣ ⌘ V V V 0.974 0.225 0.00351 | ud||us||ub| Vcd Vcs Vcb = 0.225 0.973 0.0412 0|V ||V ||V |1 00.00867 0.0404 0.999 1 | td||ts||tb| @ A @ A 2 F2(x)=x eqi (qi(x)+qi(x)) i X ⇡+ µ+⌫ ! µ SN1987A K+ µ+⌫ ! µ IMB Kamiokande Baksan µ+ e+⌫ ! e 8 events 12 events 5 events +/0 ⌫ + n(p) H + l− • Events occurred over a 13! second period • Events are from ⌫ + p n + e+ e ! with maybe 1-2 from (anti)neutrino electron scattering ⌫ + n p + e− 57 • Corresponds to a totale neutrino! flux of 8x10 ν and 2±1x1053 erg gravitational collapse energy • Model dependent mass⌫ + e− limit ⌫m+ν <e −5.7 eV ! • Very good measurement of the neutrino velocity... that of light 37 37 12 ⌫ + Cl Ar + e− e 17 ! 18 37 37 e− + Ar ⌫ + Cl +2.85kevγ 18 ! e 17 71 71 Ga + ⌫ Ge + e− e ! 8 Super Kamiokande 13 Super-Kamiokande • 50,000 tonnes of H2O • Established neutrino oscillations • Measured parameters of neutrino mixing which can be combined with accelerator beam experiments to yield information on the PMNS matrix • The above is a great triumph! • Note also that Kamiokande and Super-Kamiokande confirmed the solar neutrino deficit by observing neutrino electron scattering 14 SNO Experiment 15 Q2 = q2 − Q2 x = 2p q · p q y = · p k · Q2 = sxy s =(p + k)2 F~ = q E~ + ~v B~ ⇥ ⇣ ⌘ V V V 0.974 0.225 0.00351 | ud||us||ub| Vcd Vcs Vcb = 0.225 0.973 0.0412 0|V ||V ||V |1 00.00867 0.0404 0.999 1 | td||ts||tb| @ A @2 A F2(x)=x eqi (qi(x)+qi(x)) i X ⇡+ µ+⌫ The SNO Experiment! µ + + • 1,000 tonnes of D2OK containedµ ⌫µ in a 6m radius acrylic vessel surrounded by !a 8.5m radius geodesic sphere µ+ e+⌫ on which the tubes are! mountede in H2O +/0 • Charged current⌫ processes+ n(p) H +confirmedl− the apparent solar neutrino deficit ! + ⌫e + p n + e ! 71 71 Ge + e− Ga + ⌫e 71 ! 71 ⌫e + n p +Gee− + e− Ga + ⌫ ! ! e • This apparent problem was solved⌫ + d when⌫ + p + theyn ⌫ + e− ⌫ + e− ! measured the neutral current! ⌫ + processesd ⌫ + p + nwhich was ! 37 37 3 done in three stages⌫e + Cl 17of neutronAr18n ++ ed− detectionH + γ(6.3MeV) ! !3 – n + d H + γ(6.3MeV) 37 37 ! e− + Ar ⌫ + Cl +2.85kevγ –Add 2 tonnes of NaCl18 ! e n +1735 Cl 36 Cl + γ(8.6MeV) 35 !36 3 71 n + 71Cl Cl + γ(8.6MeV) –Add 40 He proportionalGa + ⌫e chambersGe + e!− ! • All results confirm71 the flux is71 as Bahcall calculated! Ge + e− Ga + ⌫ 16 ! e 8 9 9.