The NEUTRA beamline consists of evacuated neutron flight-tubes looking through a fixed 20mm diameter pinhole into the D2O SINQ moderator tank. This implements a pinhole optic forming an almost "parallel" neutron beam, where beam divergence decreases with increasing distance from the pinhole. Due to this divergence a geometric unsharpness in the images results , which is in the order of ug = lsample2detector / (L/D). In a flight-tube neutron flux decreases with increasing distance from the pinhole and is proportional to the pinhole area and the proton current (~1.5 mA) irradiating the SINQ target.
| NEUTRA positions for experiments | 1 | 2 | 3 |
|---|---|---|---|
| Distance from the n-aperture L [mm] | 3820 | 7292 | 10547 |
| Beam diameter [mm] | 150 | 290 | 400 |
| Neutron flux / cm2 / sec / mA | 3.68 107 | 9.8 106 | 5.1 106 |
| Collimation ratio L/D | 200 | 350 | 550 |
Typical CCD imaging parameters
| Position | Lens | Field of view [mm] | Nominal pixe size [mm] | Exposure time [sec] |
|---|---|---|---|---|
| NEUTRA 2 | Macro | 65 x 65 | 0.032 | 60 |
| NEUTRA 2 | Normal | 150 x 150 | 0.104 | 12 |
| NEUTRA 3 | Macro | 131 x 131 | 0.064 | 50 |
| NEUTRA 3 | Normal | 306 x 306 | 0.15 | 8 |
SINQ - call for proposals I-26
proposal submission deadline: 15 January 2026
The Digital User Office will be open for proposal submission approximately 4-5 weeks before the deadline. Of course editing and saving of proposals is possible any time.