P3.4 Pupil alignment

• Phase : 3
• Status : Draft
• Category : Nighttime testing (functionality and operability) (C4)
• Recurrence : before every observing target (CI, LSS), starting from commissioning.
• Duration : 2.5 hours

Description

• Alignment of the internal pupil image (PP1)with apodizer [and Lyot stop at PP2]in the coronagraphic mode

Prerequisites

• Bad pixel map, Background or Dark, Flat-field, detector RON

Procedure

• The position of the first tip-tilt mirror (IN_TT) is optimized in order to have the first pupil image centered with the apodizer. This is obtained comparing the pupil image, formed on the SCICAM, with the image of the apodizer, obtained on the SCICAM using the calibration fiber as a source.

Success criteria

• Expected accuracy: 0.25% of pupil image diameter ~17arcsec of the TTM ~1.5pixel SCICAM ~30μm at the level of the SCICAM.

Notes

• Same as activity 8.2 in AD4

LBTO support

Associated SHARK-NIR personnel

Date performed and by whom

Comment

KR, EC, DV: Should we do this also for Lyot Stops (Lyot_Grism_W) or PP2? Do we need to do the pupil alignment for the Prism or Grism (we think not)? Considering 5 cases (3 + 2) and 30 mins / case, we put 2.5 hours in total above. DV: yes, I confirm we need this procedure also for Lyot Stops on PP2. We started iterations with Depa/DavideR to adapt the template. DG: No fine alignment should be required for prism and grism every time we need them in night-time. We do not expect flectures strong enough to introduce vignetting, but we will have to ckeck it with tests.