From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001
From: Joseph Hunkeler <jhunkeler@gmail.com>
Date: Wed, 8 Jul 2015 20:46:52 -0400
Subject: Initial commit

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+.help refco Jun99 "Slalib Package"
+.nf
+
+      SUBROUTINE slRFCO (HM, TDK, PMB, RH, WL, PHI, TLR, EPS,
+     :                      REFA, REFB)
+
+     - - - - - -
+      R F C O
+     - - - - - -
+
+  Determine the constants A and B in the atmospheric refraction
+  model dZ = A tan Z + B tan**3 Z.
+
+  Z is the "observed" zenith distance (i.e. affected by refraction)
+  and dZ is what to add to Z to give the "topocentric" (i.e. in vacuo)
+  zenith distance.
+
+  Given:
+    HM      d     height of the observer above sea level (metre)
+    TDK     d     ambient temperature at the observer (deg K)
+    PMB     d     pressure at the observer (millibar)
+    RH      d     relative humidity at the observer (range 0-1)
+    WL      d     effective wavelength of the source (micrometre)
+    PHI     d     latitude of the observer (radian, astronomical)
+    TLR     d     temperature lapse rate in the troposphere (degK/metre)
+    EPS     d     precision required to terminate iteration (radian)
+
+  Returned:
+    REFA    d     tan Z coefficient (radian)
+    REFB    d     tan**3 Z coefficient (radian)
+
+  Called:  slRFRO
+
+  Notes:
+
+  1  Typical values for the TLR and EPS arguments might be 0.0065D0 and
+     1D-10 respectively.
+
+  2  The radio refraction is chosen by specifying WL > 100 micrometres.
+
+  3  The routine is a slower but more accurate alternative to the
+     slRFCQ routine.  The constants it produces give perfect
+     agreement with slRFRO at zenith distances arctan(1) (45 deg)
+     and arctan(4) (about 76 deg).  It achieves 0.5 arcsec accuracy
+     for ZD < 80 deg, 0.01 arcsec accuracy for ZD < 60 deg, and
+     0.001 arcsec accuracy for ZD < 45 deg.
+
+  P.T.Wallace   Starlink   3 June 1997
+
+  Copyright (C) 1997 Rutherford Appleton Laboratory
+  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
+
+.fi
+.endhelp
-- 
cgit 

