Experimental Limiting Factors for the Search of μ → eγ at Future Facilities †
Abstract
:1. Introduction
2. Materials and Methods
3. Results
3.1. Experimental Limiting Factors
3.1.1. Efficiency
3.1.2. Photon Energy
3.1.3. Positron Energy
3.1.4. Relative Angle
3.1.5. Relative Time
3.1.6. Summary
3.2. Sensitivity Reach
4. Discussion
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Scintillator | Density (g/cm) | Light Yield (ph/keV) | Decay Time (ns) |
---|---|---|---|
LaBr(Ce) | 5.08 | 63 | 16 |
LYSO | 7.1 | 27 | 41 |
YAP | 5.35 | 22 | 26 |
LXe | 2.89 | 40 | 45 |
NaI(Tl) | 3.67 | 38 | 250 |
BGO | 7.13 | 9 | 300 |
Typical figure | Comments | ||
---|---|---|---|
Calorimetry | γ Conversion | ||
Efficiency | |||
Material budget | 0.5∼0.9 | – | magnet coil |
Pair production | – | 0.02∼0.04 | 0.05∼0.1 |
Minimum energies | – | 0.8 | MeV |
Photon Energy Resolution | |||
Energy loss | – | 250∼800 keV | 0.05∼0.1 |
Photon Statistics & segmentation | 800 keV | – | |
Positron Energy Resolution | |||
Energy loss | 15 keV | ||
Tracking & MS | 100 keV | ||
Relative Angle Resolution | |||
MS on target | 2.6/2.8 mrad (/) | ||
MS on gas & walls | 3.3/3.3 mrad (/) | cm, cm, B = 1 T | |
Tracking | 6.0/4.5 mrad (/) | ||
Alignment | <1 mrad | <100 m target alignment |
Observable | One Photon Conversion Layer | Photon Calorimeter |
---|---|---|
[ps] | 60 | 50 |
[keV] | 100 | 100 |
[keV] | 320 | 850 |
Efficiency [%] | 1.2 | 42 |
[mrad] | [mrad] | |
---|---|---|
None | 7.3 | 6.2 |
TPC | 3.5 (6.1) | 3.8 (4.8) |
Silicon | 8.0 (6.3) | 7.4 (6.9) |
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Renga, F.; Cavoto, G.; Papa, A.; Ripiccini, E.; Voena, C. Experimental Limiting Factors for the Search of μ → eγ at Future Facilities. Universe 2019, 5, 27. https://doi.org/10.3390/universe5010027
Renga F, Cavoto G, Papa A, Ripiccini E, Voena C. Experimental Limiting Factors for the Search of μ → eγ at Future Facilities. Universe. 2019; 5(1):27. https://doi.org/10.3390/universe5010027
Chicago/Turabian StyleRenga, Francesco, Gianluca Cavoto, Angela Papa, Emanuele Ripiccini, and Cecilia Voena. 2019. "Experimental Limiting Factors for the Search of μ → eγ at Future Facilities" Universe 5, no. 1: 27. https://doi.org/10.3390/universe5010027