Model of the Response Function of CUORE Bolometers (eBook)

Marco Vignati received his Master Degree in Physics from the Università di Roma - La Sapienza in June 2004 with final mark 110/110 cum laude. His degree thesis was entitled “CP asymmetry measurement within b→s transitions with the BaBar experiment” and his supervisors were Prof. Fernando Ferroni and Dr. Gianluca Cavoto. In January 2010 he received his Ph.D. in Physics from the same University under the supervision of Prof. Fernando Ferroni.

Supervisor’s Foreword 7
Acknowledgments 9
Contents 10
1 Neutrino Masses and Double Beta Decay 12
1.1…Oscillations 13
1.2…Masses 15
1.3…Double Beta Decay 17
1.4…Nuclear Matrix Elements 18
1.5…Experimental Searches for Neutrinoless Double Beta Decay 20
1.6…Past and Present Experiments 22
1.7…Future Experiments 25
References 27
2 TeO2 Bolometric Detectors for 0/upnuDBD Search 29
2.1…Bolometric Detectors 29
2.1.1 The Energy Absorber 30
2.1.2 The Choice of {TeO}_2 31
2.1.3 The Sensor 32
2.1.4 NTD-Ge Thermistors 34
2.2…Bolometer Operation 34
2.3…Arrays of TeO2 Bolometers 36
2.4…Cryogenic Setups 36
2.5…Signal Readout 38
2.5.1 Measurement of the Static Resistance 39
2.6…Detector Noise 40
2.7…CUORICINO and CUORE 41
References 44
3 Model of the Response Function of CUORE Bolometers 45
3.1…The CCVR Run 45
3.2…The Model 47
3.2.1 Thermistor Model 47
3.2.2 Biasing Circuit 51
3.2.3 Bessel Filter 52
3.2.4 Thermal Model 53
3.2.5 Simplified Model Without Temperature Dependences 54
3.2.6 Fit to Data 57
3.2.7 Response Function Simulation 58
3.2.8 Amplitude Dependence on the Working Temperature 60
3.2.9 Extraction of R_S from the Relationship Between Amplitude and Baseline 62
References 65
4 Thermal Response Analysis 66
4.1…Data Analysis Procedure 66
4.2…The Thermal Response Algorithm 67
4.3…Check of the TR Algorithm on MonteCarlo Data 68
4.4…Data Analysis 70
4.4.1 Calibration 73
4.5…Residual Drift in Time 77
4.6…Sources of Systematic Errors 80
4.6.1 Choice of the Derivative Algorithm 81
4.6.2 Error on the Biasing and Read-Out Circuits Parameters 82
References 83
5 Thermal Response Analysis on the Three Towers Detector 84
5.1…The Three Towers Detector 84
5.2…Measurements of Model Parameters 85
5.2.1 Measurement of V_{R_S}^G and V_S 86
5.2.2 Measurement of G/G_S 88
5.2.3 Measurement of R_L 88
5.2.4 Measurement of V_B G_S 89
5.2.5 Measurement of c_p 90
5.3…Results on Calibration Data 92
5.4…Results on Background Data 95
5.5…Future Developments 97
Reference 98
6 Conclusions 99
Reference 103
Appendix AThermal Response Analysis on the CCVR Detector 104
Appendix B Precision Measurements on the Three Towers Detector 109