Neutrino Physics - Lecture 4
description
Transcript of Neutrino Physics - Lecture 4
![Page 1: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/1.jpg)
Neutrino Physics - Lecture 4
Steve Elliott
LANL Staff Member
UNM Adjunct Professor
505-665-0068, [email protected]
![Page 2: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/2.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
2
Lecture 4 Outline
• Neutrinos from the SunThe neutrinos
Past experiments
What we know and what we want to learn
![Page 3: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/3.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
3
Cl Results
2.56 ± 0.16 ± 0.16 SNU
Expect7.5 SNU
![Page 4: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/4.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
4
SAGE and Gallex (GNO)
• 71Ga(e,e)71Ge
• 71Ge has 11.4 day half life.
• Expose Ga to neutrinos
• Extract Ge and count via its decay
• Decays of 71Ge are by electron capture: the signature is the 1.2 or 10.4 keV x rays, Auger electrons
![Page 5: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/5.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
5
SAGE Operations
1. Add carrier to Ga.2. After about 3-4 weeks, extract
Ge carrier and solar neutrino induced Ge.
3. Synthesize counter gas and fill proportional counter.
4. Count sample for about 6 months.
![Page 6: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/6.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
6
Map to SAGE
![Page 7: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/7.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
7
Baksan Valley, UG Laboratory
![Page 8: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/8.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
8
Source Calibration
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
92.4% enriched in 50Cr512.7 g of CrIrradiated for ~3 mnths517 kCi activity
![Page 9: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/9.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
9
Reactor Layout
10 reactorsEach can hold 8 tons of GaKept warm so Ga is liquid
![Page 10: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/10.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
10
Proportional Counters
• R: recombination• IC: ionization
chamber• PC: proportional
chamber• GC: Geiger counter• D: continuous
discharge
R
IC
PC
GC
D
Voltage
Co
llec
ted
Io
ns
![Page 11: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/11.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
11
Proportional Counter Spectrum
![Page 12: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/12.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
12
Results - Solar Rate
€
66.9−3.8, −3.2+3.9, +3.6 SNU
Expect128 SNU
Each run saw about 6 signalEvents.
![Page 13: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/13.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
13
Gran Sasso
Italy:Not too far from Rome
![Page 14: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/14.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
14
GNO Layout
![Page 15: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/15.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
15
GALLEX Results
Expected128 SNU
![Page 16: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/16.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
16
Kamiokande & SuperK
• Elastic scattering of e-
in a large water detector
• Mostly sensitive to e because CC cross section is about 6x higher than NC
![Page 17: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/17.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
17
Cherenkov Radiation
“Electrons in the atoms of the medium will be displaced and polarized by the passing EM field of a charged particle. Photons are emitted as an insulator's electrons restore themselves to equalibrium after the disruption has passed. (In a conductor, the EM disruption can be restored without emitting a photon.) In normal circumstances, these photons destructively interfere with each other and no radiation is detected. However, when the disruption travels faster than the photons themselves travel, the photons constructively interfere and intensify the observed radiation.”
Wikipedia
€
cosθ =1nβ
![Page 18: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/18.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
18
Photomultiplier Tubes
![Page 19: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/19.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
19
SuperKamiokande Characteristics
• 50,000 t water
• 11,146 20” pmt
• 1,885 8” pmt
![Page 20: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/20.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
20
SuperK Data
![Page 21: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/21.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
21
SNO
• ES, CC, and NC
• CC: d(e, pp)e-
– Sensitive only to e
• NC: d(x, np)x
– Sensitive to all x
• NC/CC ratio
![Page 22: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/22.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
22
SNO’s Location
< 100 /day102
103
104
105
106
107
Muon flux (m
-2 y
-1)
8000600040002000Depth Underground (ft)
IMB
Soudan
Kamioka
Gran Sasso
Frejus, Baksan, Homestake Mont Blanc
Sudbury
Kolar
![Page 23: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/23.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
23
The SNO Detector
9438 inward & 91 outwardWith concentrators = 54% coverage
Control room
Vectransupportropes
Urylon liner
5300 tonneslight water
1000 tonnesheavy water 1700 tonnes
light water
2039 m to surface1011 m to Sun
12 m diameteracrylic vessel
Support structure for 9500 PMTs,concentrators
Norite rock
![Page 24: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/24.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
24
SNO Calibration
Electronics CalibrationsBuilt-in programmable pulsers
Optical CalibrationsLaser ball: attenuation, scattering, reflectivity
Energy Calibrations16N source: 16O(n,p)16N*
-tagged 6.1-MeV source8Li Source: e- spectrum similar to 8B252Cf source: fission neutron source
Encapsulated U/Th source (low-E ’s)3H(p, )4He: 19.8-MeV Triggered U: Th sources (low-E ’s)
Michel electrons
![Page 25: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/25.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
25
An example Event: atmospheric neutrino
![Page 26: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/26.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
26
SNO data
Radius of event vertex Angle with Sun
![Page 27: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/27.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
27
Event Energy
![Page 28: Neutrino Physics - Lecture 4](https://reader036.fdocuments.us/reader036/viewer/2022062500/5681596c550346895dc6ad5d/html5/thumbnails/28.jpg)
Spring 2007 Steve Elliott, UNM Seminar Series
28
NC vs. CC