P3.17 Orient the apodizers

• Phase : 3
• Status : Draft
• Category : Nighttime testing (functionality and operability) (C5) + Nighttime calibration (C6)
• Recurrence : before every observing target (CI, eventually LSS?), starting from commissioning.
• Duration : 4 hours

Description

• Adjust the orientation of the Shaped Pupil apodizers with respect to the true orientation of the M2 spider by rotating the SHARK-NIR derotator.

Prerequisites

• Atmospheric conditions: should be able to see bright stars in the sky (preferably close to zenith?).
• Authorize SHARK-NIR on the SX side.
• Suitable bright enough star close to zenith to have negligible effects from flexures (including the possibility of performing AO).

Procedure

• Insert the apodizer in the path and measure its orientation on SCICAM illuminating it with the internal fiber. Then point a star, remove the apodizer and measure the orientation of the M2 spider on SCICAM. Rotate the bearing by the delta between the two orientations. Iterarate, if necessary, until delta is below 0.5deg.

Templates

• SHARKNIR_gen_tec_PupilApoAlignment

Success criteria

• The apodizer is aligned to the true orientation of the M2 spider by minimizing their differential orientation on SCICAM.
• Note down the contrast achieved, including the atmospheric conditions and the brightness of the on-axis star.

Notes

LBTO support

• AO support

Date performed and by whom