Apply Refraction to Vector
CALL sla_REFV (VU, REFA, REFB, VR)
VU  D  unrefracted position of the source ($\left[\phantom{\rule{0.3em}{0ex}}Az,El\phantom{\rule{1em}{0ex}}\right]$ 3vector) 
 
REFA  D  $tan\zeta $ coefficient (radians) 


REFB  D  ${tan}^{3}\zeta $ coefficient (radians) 
VR  D  refracted position of the source ($\left[\phantom{\rule{0.3em}{0ex}}Az,El\phantom{\rule{1em}{0ex}}\right]$ 3vector) 
${\zeta}_{obs}$  error  
$8{0}^{\circ}$  ′′07  
$8{1}^{\circ}$  ′′13  
$8{2}^{\circ}$  ′′25  
$8{3}^{\circ}$  $5\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$8{4}^{\circ}$  $10\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$8{5}^{\circ}$  $20\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$8{6}^{\circ}$  $55\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$8{7}^{\circ}$  $160\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$8{8}^{\circ}$  $360\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$8{9}^{\circ}$  $640\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$9{0}^{\circ}$  $1100\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  
$9{1}^{\circ}$  $1700\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  $<$ highaltitude 
$9{2}^{\circ}$  $2600\phantom{\rule{0.54753pt}{0ex}}$${}^{\prime}{\phantom{\rule{1.09506pt}{0ex}}}^{\prime}$  $<$ sites only 