Setup of a Drift Tube Muon Tracker and Calibration of Muon ...

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withx ≡ V W/2∆m 2 /4E ν= 2√ 2G F N e E ν∆m 2 , (2.7)the oscillation probability for a ν α → ν β transition in matter is simply expressed by:( ) 1.27∆mP m,να→ν β= sin 2 (2θ m )sin 2 2m L. (2.8)E νThe oscillation probability in matter now has the same outline as in the vacuumcase presented in Eq. 2.3, with a different effective mixing angle θ m and squaredmass splitting ∆m 2 m. As can be seen from Eq. 2.7, these effective values dependon the neutrinos energy. Hence, the influence of matter effects on the oscillationprobability is energy dependent. As will be shown in Section 2.3, matter effects playan important role in the oscillation of solar neutrinos. The change of flavor for solarneutrinos inside the Sun is described by the Mikheyev-Smirnov-Wolfenstein (MSW)effect.Different scenarios have been suggested for matter enhanced oscillations. Themost popular mechanism is the large mixing angle solution of the MSW effect (MSW-LMA). In this scenario, a strong energy dependence of the matter effect is limitid toa small energy regime. From Eq. 2.5 and 2.6 one can see that the effective squaredmass splitting and mixing angle are close to those of vacuum oscillations in casex < cos 2θ. On the other hand, for values of x > 1, the oscillation probabilityP m,να→ν βis dominated by matter effects. The region between these limits is calledthe transition region.Other theories include an extension of the MSW effect by non standard interaction(MSW-LMA-NSI) [36,37] or the so called mass-varying neutrino oscillations(MaVaN) [38]. Non standard interactions would result from processes exceedingthe standard model and would allow for neutrinos to interact by other means thanjust the exchange of W or Z gauge bosons. This would add an additional potentialto be considered in the neutrino’s evolution in matter, leading to deviations in theenergy dependent oscillation probability. Very interestingly, only the transition regionof matter enhanced oscillations is notably affected by this effect, whereas thevacuum-like and matter-dominated regions are left unchanged [39].2.3 Solar NeutrinosThe Sun is the most prominent source for neutrinos reaching the Earth. Solar neutrinosoriginate from fusion processes in the Sun’s core. In this section the mainprocesses of energy production in the Sun are described. The impact of matter enhancedneutrino oscillations for solar neutrinos is presented. Finally it is shown thatinvestigating solar neutrinos can give answers to open questions in both oscillationand solar physics.2.3.1 Fusion Processes in the SunThe energy production in stars has been first described by Hans Bethe in 1939 [40].He assumed nuclear fusion to be the source of energy radiated by the Sun. Based on10
this assumption, the Standard Solar Model (SSM) was developed which describesthe physical processes of our Sun. The Sun consists mainly of hydrogen being heldtogether by gravitation. Towards the core of the Sun, pressure and temperatureget high enough to allow for thermonuclear processes. These include mainly fusionof four protons to one helium atom. The two main cycles for this process are theproton proton (pp) chain and the CNO (carbon - nitrogen - oxygen) cycle:pp chain:The pp chain starts with one of the two processesp + p → d + e + + ν e (pp : 99.77%)p + e − + p → d + ν e (pep : 0.23%)followed byd + p → 3 He + γ.The pp chain then splits up into four branches, mainly depending on the ambienttemperature:pp I (85%):3 He + 3 He → 4 He + p + ppp III (0.016%):3 He + 4 He → 7 Be + γ7 Be + 1 H → 8 B + γpp II (15%):3 He + 4 He → 7 Be + γ7 Be + e − → 7 Li + ν e7 Li + p → 4 He + 4 He8 B → 8 Be + e + + ν e8 Be ↔ 4 He + 4 Hepp IV /hep (10 −6 %):3 He + 1 H → 4 He + ν e + e +CNO-cycle:CNO I: (99.96%)12 C + 1 H → 13 N + γ13 N → 13 C + e + + ν e13 C + 1 H → 14 N + γ14 N + 1 H → 15 O + γ15 O → 15 N + e + + ν e15 N + 1 H → 12 C + 4 HeCNO II: (0.04%)15 N + 1 H → 16 O + γ16 O + 1 H → 17 F + γ17 F → 17 O + e + + ν e17 O + 1 H → 14 N + 4 He14 N + 1 H → 15 O + γ15 O → 15 N + e + + ν eThe pp cycle is the dominating process in our Sun. The contribution of the CNOcycle to the Sun’s luminosity depends mainly on the core temperature. The SSMcurrently predicts ≃ 1.6% of the solar luminosity to be generated by the CNO cycle.11
Page 1 and 2: Setup of a Drift Tube Muon Trackera
Page 3: AbstractIn this work the setup and
Page 6 and 7: 3.5.5 Pattern Recognition . . . . .
Page 8 and 9: viii
Page 10 and 11: essential for vetoing these events.
Page 13 and 14: Chapter 2NeutrinosThe standard mode
Page 15 and 16: However, it did not yet deliver an
Page 17: Table 2.1: Neutrino oscillation par
Page 21 and 22: Figure 2.1: Neutrino flux at Earth
Page 23 and 24: asymmetry between neutrino and anti
Page 25 and 26: Figure 2.3: Expected ¯ν e energy
Page 27: Nb neutrino/fission-11010-2Neutrino
Page 30 and 31: 108−dE/dx (MeV g −1 cm 2 )65432
Page 32 and 33: Figure 3.3: Setup of the muon track
Page 34 and 35: zyxModule b.0Module a.0Module b.1Mo
Page 36 and 37: Figure 3.6: Display of the slow con
Page 38 and 39: plastic scintillators. To avoid all
Page 40 and 41: N hitsHitmap Plane 06000h_hitmap0En
Page 42 and 43: Table 3.4: Data structure for calib
Page 44 and 45: TDC SpectrumN/[2 Channels]1000800H_
Page 46 and 47: Table 3.5: List of variables calcul
Page 48 and 49: with ∆⃗q = ⃗q n − ⃗q n−
Page 50 and 51: N [a.u.]∆ α (x)2200020000da0Entr
Page 52 and 53: d[mm]Reco Drift Distances201816H_RE
Page 54 and 55: N [a.u.]Real DataReal data0.06MCh1E
Page 56 and 57: χ 2N [a.u.]Probability103×10hc2p0
Page 58 and 59: N [a.u]Residuals20001800h0Entries 3
Page 60 and 61: Counts/(10 keV × day × 100 tons)1
Page 62 and 63: 4.1.3 Čerenkov LightČerenkov dete
Page 64 and 65: 4.2 The Borexino DetectorThe Borexi
Page 66 and 67: muons, is reduced by going deep und
Page 68 and 69:
(typically below 50 cm), the locati
Page 70 and 71:
510Counts/(10 keV x day x 100 tons)
Page 72 and 73:
counts/days*4 hitsDay (Red) and Nig
Page 74 and 75:
eeSurvival probability for ν e, P0
Page 76 and 77:
the CMT to the Borexino tracking, t
Page 78 and 79:
P C P DSCINT C SCINT DySCINT BSCINT
Page 80 and 81:
Figure 5.2: The CMT setup on top of
Page 82 and 83:
Angular AcceptanceAngular Acceptanc
Page 84 and 85:
Comparison nhits=3 vs nhits=4N [a.u
Page 86 and 87:
Table 5.3: Overview of all muon run
Page 88 and 89:
N/dayAll Triggers vs Time12000h_tim
Page 90 and 91:
Reco Hits in Scintillatory [mm]1000
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PMTPMTScintillatorPMTPMTFigure 5.16
Page 94 and 95:
the CMT data file and the Borexino
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Zenith Angle CMT and BX-GL Tracks h
Page 98 and 99:
Lateral x Resolution CMT - IDhlatx_
Page 100 and 101:
Distance d between CMT and BX-GL Tr
Page 102 and 103:
Angular difference αN [arbitrary u
Page 104 and 105:
[m]z bxTrack Position in BX x=0 Pla
Page 106 and 107:
N [arbitrary units]∆y all data200
Page 108 and 109:
To determine the Borexino tracking
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Table A.1: Variables that can be se
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espectively. The channel numbers ar
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xyϕϕ ′βx ′µFigure C.2: Rela
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the z-coordinate z op,0 of the firs
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xyEvent: 470, Entry: 470, Time Tue
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[14] Ch. Kraus et al. Final Results
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[49] T. Araki et al. Experimental i
Page 124 and 125:
116
Page 126:
Jan Lenkeit und Björn Wonsak sowie
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