2.  Myth: 3 sec memory  Reality: 3 years are passed  I’m not a goldfish, but…

3.  From PLATO-CAMTO-TS-90-LESIA  Dimension ed energy of Ghosts ▪ Extended and pointlike  Absent: requirements on scattered straylight ▪ Once there was a requirement: 20ph/pxl/s, but has been excluded (or forgot…), or my copy of the doc… ▪ Reduce to a PST/rejection requirement?  Requirements on transmission (to limit ‘blue’ light)  Requirements on cleanliness levels (not justified)

4.  It is the model of reference ZEMAX  Based on a slightly old design (some radii of curvature)  Structure is semiconceptual (tube & diaphgrams) 90% absorbing, 10% lambertian scattering  All lenses and window (front face included) have 1% AR coating  20A microroughness and CL500 dust on window  The CCD has a 1-QE reflectivity  Fed by a 240mm diam circular collimated source of 4W (1W on the entrance pupil), moved along the diagonal of FoV  Wavelength weighted to reproduce energy of a G0

5.  TOU-OPT28: Should a ghost image be focused on the detector, its relative intensity shall be less than 0.2% (TBC) of the flux of the star which creates the ghost.  Due to the presence the flat window  Using Rlenses=1%, Rccd=1-QE Deltam~6

6.  TOU-OPT27: The surface of ghost light beams at the detector surface shall be greater than 3000 pixels (TBC). 23456789101112131415 10.65737539081546205528346407781254665771325060339658990208175121291644580337111397821635533.917923.5991.405447 238505771154429101061552556814913249169396527892094953912915525205152.61397608135512.387921.9341.371451 376796589792328381444653659813598121534525317.9457636682621703876100506537614222646808930286981 4300696648918990327550676336052853172592298754503291802647295199934182058029544374436 5728868314989225967672385661567.945715989590808247119158411535033421622808424 67042414166368402930255576840087781904428861717913725591440076216567682 7845306098266808311078335577099414129048217989909264854311070 8220941366079763279708376326822959853061824794619956264 98256939359280938938899038298264109338079554658 10791967302672098123297337846439592194 112327847449165531351733910651 1297347771917878816979918 1324315.9159146.8 1438899.98 Column Min0.65737538505771154429101061551444653613249169121534525317.9412915525205152.6232784735512.387921.93438899.98

7. Up to mNstarsUp to mNstarsUp to mNstarsUp to mNstars 007808151.73E+06221.36E+08 1182311164.41E+06231.79E+08 2496640171.02E+07242.28E+08 3121014338182.11E+07252.85E+08 4341133519193.87E+07263.49E+08 5981284452206.40E+07274.22E+08 628213228308219.74E+07285.05E+08 14635252 296.00E+08 Based on Allen (1973) m<10 Bahcall&Soneira m>10 Spectrum: G0 Number of stars in Plato TOU field up to the m mag

8.  Build a Ghost Simulator form several (105) zemax files and IDL routines.  Used in two ways  Single source: to extract data of ghosts: positions, radius and percentage of rays entering the pupil that can form the ghost  Multi source: using the previous stellar model, to simulate an entire field

9. MagStar Extended Ghosts Point-like ghosts Average due to extended ghostsVariance 0000 0.00E+00 11.69E+091.43E+060 1.76E-029.80E-02 22.02E+091.83E+060 2.25E-025.36E-02 32.14E+092.04E+06113901 2.51E-022.44E-02 42.02E+092.52E+062.75E+06 3.09E-021.17E-02 52.42E+092.73E+062.06E+06 3.36E-025.71E-03 62.79E+093.04E+061.79E+06 3.74E-023.34E-03 73.06E+093.32E+061.59E+06 4.08E-021.57E-03 83.55E+093.80E+061.79E+06 4.67E-021.15E-03 93.96E+094.10E+061.77E+06 5.05E-027.30E-04 102.92E+093.07E+061.52E+06 3.78E-023.83E-04 112.82E+093.01E+061.52E+06 3.70E-023.47E-04 123.02E+093.21E+061.66E+06 3.94E-023.70E-04 133.39E+093.58E+061.74E+06 4.40E-024.37E-04 143.81E+094.03E+061.99E+06 4.96E-025.50E-04 TOTAL3.96E+104.17E+072.03E+07 5.13E-01 Brightes features are present from the beginning Adding higher mags adds an offset Evolution of extended ghosts with mag

10. Inside FoV is 2-2.5% (was 1% without CCD reflection) Outside FoV is similar to old 6 lenses or better because the tube is larger and exactly the same of that of ‘6 lenses’ Stars + Zodiacal light

11.  3 ‘families’ and 5 models  1-4,2-3 (N), 5(F)  Composed by two part  interface ring: ▪ identical for all models, ▪ is the interface with the TOU tube ▪ ‘hosts’ the window  Cone: ▪ different cut angle and height according to family ▪ Different orientations according to model TypeCut Angle Rotation angle H N exemplars 137.039.051178 224.314.23157 (92)?8 324.3-14.23157 (92)?8 437.03-9.051178 53001002

12.  Not for “direct” stray light from astronomical objects (they are too small)  Thermal?  On a ‘prudence basis’ to ‘fight’ TOU mutual scattering and satellite (sunshield) scattering  At the moment we don’t have any simulation to support that ▪ Simulations are difficult because ▪ We need information about all the system (disposition of TOUs, materials, sunshield…) ▪ The system is big but the single TOU pupil is small: raytracing may have poor statistic

13.  Requirements (from system?)  Model  Migration to ASAP  Optical design  Mechanical design  Coatings  Sources  Check calculations ph/s/pxl  Earth /Moon  Satellite / Mutual scattering