| 1 | offset |
|---|
| 2 | #figuring out how much a positional offset matters to HPF centering |
|---|
| 3 | # |
|---|
| 4 | #assuming a moffat PSF of star |
|---|
| 5 | #HPF science fiber is 1.7" diameter (octagonal, but treat as circle) |
|---|
| 6 | |
|---|
| 7 | precalc |
|---|
| 8 | |
|---|
| 9 | #calculate flux at a given offset (x,y in arcsec) |
|---|
| 10 | echo (0.0,0.0) |
|---|
| 11 | docalc 0.0 0.0 |
|---|
| 12 | echo "" |
|---|
| 13 | |
|---|
| 14 | echo (0.1,0.1) |
|---|
| 15 | docalc 0.1 0.1 |
|---|
| 16 | echo "" |
|---|
| 17 | |
|---|
| 18 | echo (0.2,0.2) |
|---|
| 19 | docalc 0.2 0.2 |
|---|
| 20 | echo "" |
|---|
| 21 | |
|---|
| 22 | echo (0.3,0.3) |
|---|
| 23 | docalc 0.3 0.3 |
|---|
| 24 | echo "" |
|---|
| 25 | |
|---|
| 26 | echo (0.5,0.5) |
|---|
| 27 | docalc 0.5 0.5 |
|---|
| 28 | echo "" |
|---|
| 29 | |
|---|
| 30 | |
|---|
| 31 | |
|---|
| 32 | precalc |
|---|
| 33 | #make a grid? use "image" from SM?? |
|---|
| 34 | # coordinate 50,50 is center 1,1 and 100,100 are min/max |
|---|
| 35 | #treat this range as covering -5 to +5 arcsec, so index step is 0.1" |
|---|
| 36 | IMAGE ( 100, 100 ) |
|---|
| 37 | define step 0.1 |
|---|
| 38 | define xcent 50 |
|---|
| 39 | define ycent 50 |
|---|
| 40 | |
|---|
| 41 | define fwhm_arcsec 1.3 |
|---|
| 42 | |
|---|
| 43 | |
|---|
| 44 | define fwhm $($fwhm_arcsec/$step) |
|---|
| 45 | |
|---|
| 46 | #populate 2-D array with PSF |
|---|
| 47 | do x=0,99 { do y=0,99 { |
|---|
| 48 | #calculate radius of this pixel |
|---|
| 49 | define r $(sqrt( ($x-$xcent)**2 + ($y-$ycent)**2 )) |
|---|
| 50 | #echo $x $y $r |
|---|
| 51 | moffat $r |
|---|
| 52 | set image[$x,$y]=$moffat |
|---|
| 53 | }} |
|---|
| 54 | |
|---|
| 55 | verbose 0 |
|---|
| 56 | |
|---|
| 57 | |
|---|
| 58 | |
|---|
| 59 | |
|---|
| 60 | |
|---|
| 61 | |
|---|
| 62 | |
|---|
| 63 | |
|---|
| 64 | docalc 2 |
|---|
| 65 | #calculate enclosed flux in a 1.7" diameter fiber |
|---|
| 66 | define _xoff $1 #0.0 |
|---|
| 67 | define _yoff $2 #0.0 |
|---|
| 68 | #MAX is 2 arcsec, or else we lose too much |
|---|
| 69 | if ($_xoff>2 || $_yoff>2){ |
|---|
| 70 | echo OFFSET must be less than 2arcsec |
|---|
| 71 | define $0 0 |
|---|
| 72 | } ELSE { |
|---|
| 73 | define fsum 0.0 |
|---|
| 74 | define diameter_arcsec 1.7 |
|---|
| 75 | define rmax $(0.5*$diameter_arcsec/$step) |
|---|
| 76 | do _x=0,99 { do _y=0,99 { |
|---|
| 77 | #calculate radius of this pixel |
|---|
| 78 | define r $(sqrt( ($_x-$xcent+$_xoff/$step)**2 + ($_y-$ycent+$_yoff/$step)**2 )) |
|---|
| 79 | if ($r <= $rmax) { |
|---|
| 80 | define fsum $($fsum+$(image[$_x,$_y])) |
|---|
| 81 | } |
|---|
| 82 | }} |
|---|
| 83 | define $0 $($fsum/161.38) |
|---|
| 84 | echo $(sprintf('%3.3f',$$0)) of centered at $1 $2 |
|---|
| 85 | } |
|---|
| 86 | |
|---|
| 87 | |
|---|
| 88 | |
|---|
| 89 | |
|---|
| 90 | |
|---|
| 91 | |
|---|
| 92 | |
|---|
| 93 | |
|---|
| 94 | func 1 |
|---|
| 95 | define $0 $($1+2) |
|---|
| 96 | moffat 1 |
|---|
| 97 | define beta 4.765 |
|---|
| 98 | define alpha $($fwhm * 0.5 / sqrt(2**(1/$beta) - 1)) |
|---|
| 99 | define $0 $(1e0 * (1 + ($1/$alpha)**2 )**(-$beta)) |
|---|
| 100 | |
|---|
| 101 | |
|---|
| 102 | a |
|---|
| 103 | macro read offset.sm |
|---|
| 104 | offset |
|---|
