SLIDE 1
CRESST (Data Analysis)
Philipp Bauer
MPP
September 7, 2018
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Goal of this talk
Very brief overview over the CRESST Experiment.
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CRESST (Data Analysis) Philipp Bauer MPP September 7, 2018 1 / 22 - - PowerPoint PPT Presentation
CRESST (Data Analysis) Philipp Bauer MPP September 7, 2018 1 / 22 - - PowerPoint PPT Presentation
CRESST (Data Analysis) Philipp Bauer MPP September 7, 2018 1 / 22 Goal of this talk Very brief overview over the CRESST Experiment. 2 / 22 Goal of this talk Very brief overview over the CRESST Experiment. Please try to spot things relevant
SLIDE 2
SLIDE 3
Goal of this talk
Very brief overview over the CRESST Experiment. Please try to spot things relevant for you and ask us about the details later.
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SLIDE 4
CRESST
Cryogenic Rare Event Search with Superconducting Thermometers
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SLIDE 5
CRESST
Cryogenic Rare Event Search with Superconducting Thermometers Direct dark matter particle detection experiment
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SLIDE 6
CRESST
Cryogenic Rare Event Search with Superconducting Thermometers Direct dark matter particle detection experiment Direct: interaction of natural dark matter with the detector ⇒ Rare
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SLIDE 7
CRESST
Cryogenic Rare Event Search with Superconducting Thermometers Direct dark matter particle detection experiment Direct: interaction of natural dark matter with the detector ⇒ Rare Cryogenic detectors → 10-20mK
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SLIDE 8
CRESST
Cryogenic Rare Event Search with Superconducting Thermometers Direct dark matter particle detection experiment Direct: interaction of natural dark matter with the detector ⇒ Rare Cryogenic detectors → 10-20mK Detection by energy/heat deposition measured by a special thermometer
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SLIDE 9
1
Detector Working Principle
2
Data Acquisition
3
Data Analysis
4
Results
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SLIDE 10
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
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SLIDE 11
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
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SLIDE 12
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
Dark Blue: Absorber crystal and holdings sticks (CaWO4)
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SLIDE 13
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
Dark Blue: Absorber crystal and holdings sticks (CaWO4) Red: Thermometers (TES)
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SLIDE 14
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
Dark Blue: Absorber crystal and holdings sticks (CaWO4) Red: Thermometers (TES) Black: Light detector
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SLIDE 15
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
Dark Blue: Absorber crystal and holdings sticks (CaWO4) Red: Thermometers (TES) Black: Light detector Light Blue: Scintillating and reflective foil
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SLIDE 16
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Modules
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SLIDE 17
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
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SLIDE 18
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition
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SLIDE 19
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition
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SLIDE 20
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition Small temperature changes lead to big resistance changes
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SLIDE 21
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition Small temperature changes lead to big resistance changes Read out with a SQUID system
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SLIDE 22
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition Small temperature changes lead to big resistance changes Read out with a SQUID system Very sensitive (Detector threshold in the end ≈100eV)
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SLIDE 23
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition Small temperature changes lead to big resistance changes Read out with a SQUID system Very sensitive (Detector threshold in the end ≈100eV) Requires a temperature stabilization
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SLIDE 24
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Thermometers
Superconductor stabilised within its phase transition Small temperature changes lead to big resistance changes Read out with a SQUID system Very sensitive (Detector threshold in the end ≈100eV) Requires a temperature stabilization Limited linear and dynamic range
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SLIDE 25
Detector Working Principle Data Acquisition and processing
CRESST Detectors - Shielding and Location
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SLIDE 26
Detector Working Principle Data Acquisition Analysis
Continuous Data Acquisition
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SLIDE 27
Detector Working Principle Data Acquisition Analysis
Continuous Data Acquisition
The analog voltage output from the detector side is continuously sampled, digitized and written to disc: Rising flank: Energy deposition leads to a sharp rise (≈1ms) in temperature and re- sistance Falling flank: Detector and ther- mometer cool slowly (≈100ms) via coupling to the heatbath
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SLIDE 28
Detector Working Principle Data Acquisition Analysis
Continuous Data Acquisition
The analog voltage output from the detector side is continuously sampled, digitized and written to disc: Rising flank: Energy deposition leads to a sharp rise (≈1ms) in temperature and re- sistance Falling flank: Detector and ther- mometer cool slowly (≈100ms) via coupling to the heatbath
10 / 22
SLIDE 29
Detector Working Principle Data Acquisition Analysis
Continuous Data Acquisition
The analog voltage output from the detector side is continuously sampled, digitized and written to disc: Rising flank: Energy deposition leads to a sharp rise (≈1ms) in temperature and re- sistance Falling flank: Detector and ther- mometer cool slowly (≈100ms) via coupling to the heatbath
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SLIDE 30
Detector Working Principle Data Acquisition Analysis
Triggering
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SLIDE 31
Detector Working Principle Data Acquisition Analysis
Triggering
Threshold trigger
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SLIDE 32
Detector Working Principle Data Acquisition Analysis
Triggering
Threshold trigger Knowledge of expected pulse shape allows filtering
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SLIDE 33
Detector Working Principle Data Acquisition Analysis
Triggering
Threshold trigger Knowledge of expected pulse shape allows filtering
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SLIDE 34
Detector Working Principle Data Acquisition Analysis
Triggering
Threshold trigger Knowledge of expected pulse shape allows filtering Triggered data is stored in the form of ”events”
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SLIDE 35
Detector Working Principle Data Acquisition Analysis
Triggering
Threshold trigger Knowledge of expected pulse shape allows filtering Triggered data is stored in the form of ”events”
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SLIDE 36
Detector Working Principle Data Acquisition Analysis
Event
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SLIDE 37
Detector Working Principle Data Acquisition Analysis
Event
This is where my work usually starts.
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SLIDE 38
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Pulse Height
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SLIDE 39
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Pulse Height
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SLIDE 40
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Peak Position
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SLIDE 41
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Peak Position
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SLIDE 42
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Peak Position
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SLIDE 43
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Right - Left Baseline
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SLIDE 44
Data Acquisition and processing Data Analysis Brief Result
Parameters and Cuts
Parameters derived from the events to better classify them and reject bad events that cannot be analyzed properly e.g.: Right - Left Baseline
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SLIDE 45
Data Acquisition and processing Data Analysis Brief Result
Energy Calibration
As a first step for the energy calibration a better measure for the pulse strength than the Pulse Height is required.
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SLIDE 46
Data Acquisition and processing Data Analysis Brief Result
Energy Calibration
As a first step for the energy calibration a better measure for the pulse strength than the Pulse Height is required. Two possibilities:
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SLIDE 47
Data Acquisition and processing Data Analysis Brief Result
Energy Calibration
As a first step for the energy calibration a better measure for the pulse strength than the Pulse Height is required. Two possibilities: Standard event fit
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SLIDE 48
Data Acquisition and processing Data Analysis Brief Result
Energy Calibration
As a first step for the energy calibration a better measure for the pulse strength than the Pulse Height is required. Two possibilities: Standard event fit Optimum filter
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SLIDE 49
Data Acquisition and processing Data Analysis Brief Result
Energy Calibration
The energy scale is fixed with a calibration measurement: 122keV ≈63.3keV (There is another step in between which insures linearity and removes time dependencies, and there are some limitations due to the dynamic range of the detector)
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SLIDE 50
Data Acquisition and processing Data Analysis Brief Result
Energy Calibration
The energy scale is fixed with a calibration measurement: 122keV ≈63.3keV (There is another step in between which insures linearity and removes time dependencies, and there are some limitations due to the dynamic range of the detector)
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SLIDE 51
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
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SLIDE 52
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
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SLIDE 53
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
18 / 22
SLIDE 54
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
18 / 22
SLIDE 55
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
19 / 22
SLIDE 56
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
19 / 22
SLIDE 57
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
19 / 22
SLIDE 58
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel: electron/gamma events nuclear recoils
19 / 22
SLIDE 59
Data Acquisition and processing Data Analysis Brief Result
Event selection
Rare event search experiments require not only an ultra low background environment but also a way to reject dominating
- backgrounds. In CRESST this is done with the help of the light
channel:
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SLIDE 60
Analysis Results
Limits (or discoveries)
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SLIDE 61
Analysis Results
Thank you for your Attention!
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