Blanco F/8 Status AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status Preliminary Optics Testing Progress Initial sequence of tests after repair completed, a couple of additional tests pending Initial analysis shows figure is essentially the same as in 1993 - one can see the same features and the same level of figure error ~0.25 waves P-V (99%) ~0.03 waves RMS ~0.1 wave astigmatism Higher level of astigmatism seen in September has been removed by the repair – stress relief of some sort? Written report will be produced on completion of optics tests Roberto Tighe will review Additional tests, if requested, will be performed Start making shipping arrangements AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status Blanco f/8 Secondary at 0 deg. minus Test Optics PV = 157 nm RMS = 19 nm AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status Preparations in La Serena New mirror-handling cart complete (shown with cell installed, missing internal components obviously) Much safer design, reviewed by non-involved staff & external experts Gear drive for cart shown before installation AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status Preparations in La Serena Mechanical fabrication of drive assemblies complete, fit-check and assembly underway (above); software and electronics also on-track for bench testing AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status So far, everything is on track for first installation exercise on telescope starting late June Dummy mirror only; first test of handling fixtures and procedures Second run = first tests with repaired mirror, starts mid-August (TBC) Contingency time planned for October bright run Re-commissioning of Cass instrument suite follows (initial work is all with ISPI) AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status – details on optical analysis AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status The composite wavefront maps with the rotating Blanco f/8 (M) and Hindle + fold flat (TO) M@0, T0@0 M@60, TO@0 M@120, TO@0 M@180, TO@0 M@240, TO@0 M@300, TO@0 are averaged to produce the Test Optics Average at 0° (Hindle sphere + fold flat) (the non-rotationally symmetric errors on the Blanco f/8 are averaged out) AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status The composite wavefront maps (rotating Blanco f/8 (M) and stationary Test Optics (TO)) M@0, TO@0 M@60, TO@0 M@120, TO@0 M@180, TO@0 M@240, TO@0 M@300, TO@0 minus TO@0 TO@0 TO@0 TO@0 TO@0 TO@0 yields M@0 M@60 M@120 M@180 M@240 M@300 AURA Observatory Council, Tucson, 3/2013

Blanco F/8 Status Note the fine scale features rotate clockwise with the secondary, M. M@0 M@60 M@120 M@180 M@240 M@300 Rotate M to 0° M@0, TO@0 M@0, TO@-60 M@0, TO@-120 M@0, TO@180 M@0, TO@-240 M@0, TO@-300 Note the fold flat support (indicating gravity) rotates counterclockwise and the fine scale features on the secondary do not. M@0 data are then averaged to produce the Blanco f/8 Secondary at 0°. PV = 157 nm RMS = 19 nm AURA Observatory Council, Tucson, 3/2013