milano 06.03.09. single step d=400mm, f=40°diag from a message of levacher about next step thermal...

MILANO 06.03.09

Single step D=400mm, f=40°Diag

From a message of Levacher about ‘next step thermal analysis’ for the baffle can be allocated a space of 400x400mm

Assuming Max Db=400mm FoV (Diag)=40° Dl=200mm

We can have Lb~250 (corresponding to max 50° offaxis,enough for Sun with K=0.5)

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

SS400mm with vanes

Vanes are used so to ensure that the entrance of the system cannot see parts of the baffle directly illuminated by the offaxis source

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

SS400MM Vanes 100% Lambertian R5%

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

IN :5E-1WOUT :1.8E-5WR=3.6E-5

Weights

Element Weight(g)

Tube 510

Front 18

Edge1 25

Edge2 36

Edge3 49

Edge4 66

Edge5 87

Edge6 109

Edge7 132

Back 153

TOTAL 1184

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Aluminium (2.7 g/cm3)0.6mm thickness

Edges

If vane edges are plane greater contributor

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Power=4.66E-6W Power=1.27E-5W

Edges

Beveled Edges, bevel oriented toward outside for the first vanes, toward inside for the others (turning point: when is impossible to light the bevel directly)

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Power=4.9E-6W

Baffle width variation (radius) (length fixed 250mm)

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Both Sizes Variation

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Complete TOU

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Lenses Front / back : no scattering AR 1% ideal Side: scatter 4% reflect 1% (No TIR)

Mountings (Baffle, vanes, stop, telescope tube, lens diaphgrams) Scatter 4% reflect 1%

CCD reflect 5% Baffle dimensions: 440dia - 250length

Weights

Element Weight(g)

Tube 561

Front 25

Edge1 34

Edge2 46

Edge3 61

Edge4 80

Edge5 102

Edge6 126

Edge7 150

Edge8 174

Back 176

TOTAL 1535

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Aluminium (2.7 g/cm3)0.6mm thickness

PST

PST= Point source transmission = detector irradiance/entrance pupil irradiance (for a point source) Irradiance= power/surface Sometime defined in slight different

ways (using power or using system aperture)

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

PST

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

25 deg ‘bump’

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Cut (and painted) last lens

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

NOISE AND SUN

From PDR Noise(ph)/ Noise(b)>3 Count(ph)/ Count(b)>9 Based on a 9 pxs psf, 40 tel phot noise 27ppm/h, G0 star

of mv=11.15 (ReferenceStar) To be budgeted beetwen zodiacal light, straylight, hot

spots, thermal noise Count(ph) is the total photon count form RS (PhRS) or

per pixel (9 pixels) photon count (PhRS/9) (Count(ph)=PhRS or count(ph)=PhRS/9)?

SUN mv=-26.75 G2 Flux ratio F(Sun)/F(RS)=~10^15 approx photon count

same ratioPhSUN=1E15*PhRS PST(50°)<1E-9 – 1E-10 For us PST(50°) ~ 1E-6 – 1E-7 SUNSHIELD!!!

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Ghosts

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

0°

10°

15°

Full detector P=6.44E-2

100x100 pxls P=6.39E-2

Issuses/Future work

TOU mechanical model SunShield Model (Zodiacal light, Out of FoV stars) Sky Model (other sources) Materials and paintings …

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

SQUARED?

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

30°cut buffle

30°cut buffle

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania

Milano, 6.3.9 Matteo Munari Salvo Scuderi - INAF OACatania