Barrel Scintillator: Difference between revisions
Nmassacret (talk | contribs) (→Scope) |
Nmassacret (talk | contribs) |
||
| Line 15: | Line 15: | ||
The barrel scintillator is constituted of 64 scintillators bars and forms a barrel which surround the TPC. The following picture present the design of this barrel. | The barrel scintillator is constituted of 64 scintillators bars and forms a barrel which surround the TPC. The following picture present the design of this barrel. | ||
[[File: | [[File:SiPM_assembly.png|frame|Light collection with Silicon PhotoMultipliers.]] | ||
This cylinder is literally a barrel due to the fact that each bar has a trapezoidal section. This reinforce naturally the structural resistance and stability of the cylinder. | This cylinder is literally a barrel due to the fact that each bar has a trapezoidal section. This reinforce naturally the structural resistance and stability of the cylinder. | ||
Revision as of 10:52, 23 May 2018
Back to Main Page
Table of Figures
Purpose
Antihydrogen annihilation identification in ALPHA crucially depends on the software capability to reject background events, i.e., cosmic rays. Given that the ALPHA-g detectors offer more information than what was available in ALPHA, new and more sophisticated algorithms will be developed to remove backgrounds events. Two types of tools will be deployed: “online” software aimed to monitor antihydrogen production and “machine learning algorithms” to eliminate background from the physics measurements.
While this software will provide the necessary rejection of the cosmic rays, the information collected for making this decision is based on a "Barrel Scintillator" layer surrounding the Radial TPC. Particles traversing this detector will leave a track of light which is recorded in time and intensity. The time correlation between different parts of the Barrel Scint. will permit the identification of the source of the particle.
Scope
Design of the Barrel Scintillator
The barrel scintillator is constituted of 64 scintillators bars and forms a barrel which surround the TPC. The following picture present the design of this barrel.
This cylinder is literally a barrel due to the fact that each bar has a trapezoidal section. This reinforce naturally the structural resistance and stability of the cylinder. The amount of bar (64) is a compromised between the acceptable quantity of data, and the azimuth (φ) resolution. The length of each bar is 2.6 meter which is enough to cover the whole 2.4 meter TPC.
Light collection
Definitions and Abbreviations
General acronyms or terms used for the ALPHA-g experiment
| rTPC | Radial Time projection Chamber |
| z | Coordinate along the main axis of the trap and rTPC |
| φ | Azimuthal coordinate, φ = 0 is in direction of cartesian x |
| θ | Angle towards the z-axis |
| r | Radial coordinate in the cylindrical rTPC system |
| pφ | φ component of the pion's original momentum |
| pθ | θ component of the pion's original momentum |
| GEANT4 | GEometry ANd Tracking, particle physics simulation package |
| Garfield++ | Gas detector simulation package |
Table 1 – ALPHA-g Abbreviations
References and Related Documents
links Sensl
Studies
Timing resolution
Amplitude correction
Mechanical structure
Description dwg, assembly