Difference between revisions of "Energy Loss (d2n)"
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=Mean Energy Loss for Outgoing Electrons= | =Mean Energy Loss for Outgoing Electrons= | ||
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| + | * For the He-3 and target side wall, starred quantities (thickness and mean energy loss) assume a scattering angle of 45 degrees. | ||
| + | * The He-4 thickness and mean energy loss assumes that the target enclosure is spherically symmetric around the interaction point. In actuality this depends on the vertex position. | ||
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| + | {| border="1" | ||
| + | | '''Material''' || '''<math>X_0</math> (cm)''' || '''Thickness (cm)''' || '''Thickness (<math>X_0</math>)''' || '''Mean Energy Loss <math>\langle E_f \rangle - E_i</math>''' | ||
| + | |- | ||
| + | |He-3 in cell || 43423 || 1.34* || 0.000031* || 0.000031* | ||
| + | |- | ||
| + | |Side wall of target cell (glass) || 7.038 || 0.156* || 0.022165* || 0.021922* | ||
| + | |- | ||
| + | |He-4 in target enclosure || 528107.5 || 79.05 || 0.000150 || 0.000150 | ||
| + | |- | ||
| + | |Air (distance is for LHRS) || 30423 || 51.23 || 0.001684 || 0.001682 | ||
| + | |- | ||
| + | |Kapton entry window (LHRS) || 28.6 || 0.0254 || 0.000888 || 0.000887 | ||
| + | |} | ||
Revision as of 20:35, 16 September 2010
We can divide the energy loss problem into two parts: energy loss for incoming electrons (before the primary scattering interaction), and energy loss for outgoing electrons (after the primary scattering interaction). The tables below, with reference to Chiranjib's dissertation, show the materials in the path of each set of electrons, plus a mean energy loss calculation for a nominal scattering angle of <math>45^{\circ}</math>.
Please note that the actual energy loss curve follows a Landau distribution, and the most likely energy loss value is NOT the same as the mean energy loss reported below.
Chiranjib Dutta's dissertation (especially the appendices) is a good resource.
Mean Energy Loss for Incoming Electrons
All thicknesses taken from Chiranjib's dissertation.
| Material | <math>X_0</math> (cm) | Thickness (cm) | Thickness (<math>X_0</math>) | Mean Energy Loss <math>E_f - E_i</math> |
| Beam pipe window (Be) | 35.28 | 0.0254 | 0.000719 | 0.00072 |
| He-4 in target enclosure | 528107.5 | 22.86 | 0.000043 | 0.000043 |
| Target entrance window (glass) | 7.038 | 0.01 | 0.00142 | 0.001420 |
| 19.8 cm (half cell length) of He-3 | 43423 | 19.8 | 0.000456 | 0.000456 |
Mean Energy Loss for Outgoing Electrons
- For the He-3 and target side wall, starred quantities (thickness and mean energy loss) assume a scattering angle of 45 degrees.
- The He-4 thickness and mean energy loss assumes that the target enclosure is spherically symmetric around the interaction point. In actuality this depends on the vertex position.
| Material | <math>X_0</math> (cm) | Thickness (cm) | Thickness (<math>X_0</math>) | Mean Energy Loss <math>\langle E_f \rangle - E_i</math> |
| He-3 in cell | 43423 | 1.34* | 0.000031* | 0.000031* |
| Side wall of target cell (glass) | 7.038 | 0.156* | 0.022165* | 0.021922* |
| He-4 in target enclosure | 528107.5 | 79.05 | 0.000150 | 0.000150 |
| Air (distance is for LHRS) | 30423 | 51.23 | 0.001684 | 0.001682 |
| Kapton entry window (LHRS) | 28.6 | 0.0254 | 0.000888 | 0.000887 |
