Spot size 23-11-2021
On this page you will find the spot size measurments performed on 23 november 2021 by Emily, Marjolein and Casimir. Spotsizes were measured by tracing the beam shape on white paper in a cardboard holder placed inside the beam. Three different tracings were measured at each distance to get a more accurate measurement. The beam is a purple square shape dot with soft borders, these soft borders make the dot difficult to trace. The measurements were performed with the exit slit opened 3.05 (mm) and the entrance slit opend 1.65 (mm) and the slits also have a square shape.
@Casimir: what does the beam look like? You say there is a slit, is the slit square or rectangular? What are the dimensions of the slit during this measurement? Are these the numbers at the top of the table? What do these numbers mean?
Measurement table
The distance in the table is measured to the inside of the vacuum chamber. To get the distance to the slit, 94 mm needs to be added to the distance in the table. See the measurement notes at the bottom of the page for the original.
| Measurements Exit 3.05(mm) Entrance 1.65 (mm) | |||
|---|---|---|---|
| Distance (mm) | Measurer | Horizontal (mm) | Vertical (mm) |
| 103 ± 1 | Casimir | 6.8 ± 0.2 | 9.1 ± 0.2 |
| Emily | 7.7 ± 0.2 | 9.5 ± 0.2 | |
| Marjolein | 7.7 ± 0.2 | 9.5 ± 0.2 | |
| Average | 7.4 ± 0.2 | 9.4 ± 0.2 | |
| 126 ± 1 | Casimir | 7.5 ± 0.2 | 9.9 ± 0.2 |
| Emily | 6.9 ± 0.2 | 10.4 ± 0.2 | |
| Marjolein | 6.5 ± 0.2 | 12.1 ± 0.2 | |
| Average | 7.0 ± 0.2 | 10.9 ± 0.2 | |
| 162 ± 1 | Casimir | 7.0 ± 0.2 | 12.3 ± 0.2 |
| Emily | 8.9 ± 0.2 | 12.7 ± 0.2 | |
| Marjolein | 8.1 ± 0.2 | 12.0 ± 0.2 | |
| Average | 8.0 ± 0.2 | 12.3 ± 0.2 | |
| 175 ± 1 | Casimir | 9.1 ± 0.2 | 11.4 ± 0.2 |
| Emily | 8.8 ± 0.2 | 11.7 ± 0.2 | |
| Marjolein | 6.8 ± 0.2 | 13.7 ± 0.2 | |
| Average | 8.2 ± 0.2 | 12.3 ± 0.2 | |
| 232 ± 1 | Casimir | 10.9 ± 0.2 | 18.0 ± 0.2 |
| Emily | 10.6 ± 0.2 | 15.9 ± 0.2 | |
| Marjolein | 13.7 ± 0.2 | 14.9 ± 0.2 | |
| Average | 11.7 ± 0.2 | 16.3 ± 0.2 | |
| 251 ± 1 | Casimir | 10.8 ± 0.2 | 18.2 ± 0.2 |
| Emily | 11.6 ± 0.2 | 15.2 ± 0.2 | |
| Marjolein | 12.8 ± 0.2 | 16.6 ± 0.2 | |
| Average | 11.7 ± 0.2 | 16.7 ± 0.2 | |
Conclusions
The beam diverges inside the sample chamber, this is expected behaviour, although we would expect a more linear behaviour. The size of the beam is larger than antisipated in previously done measurements and calculations. Therefore, one should consider to close the slits more in future experiments to reduce the size of the beam.
@Casimir: what are your conclusions? Is the behaviour as expected?