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diff --git a/src/slalib/sun67.htx/node165.html b/src/slalib/sun67.htx/node165.html new file mode 100644 index 0000000..1fadca0 --- /dev/null +++ b/src/slalib/sun67.htx/node165.html @@ -0,0 +1,176 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<!--Converted with LaTeX2HTML 97.1 (release) (July 13th, 1997) + by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds +* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan +* with significant contributions from: + Jens Lippman, Marek Rouchal, Martin Wilck and others --> +<HTML> +<HEAD> +<TITLE>SLA_REFCO - Refraction Constants</TITLE> +<META NAME="description" CONTENT="SLA_REFCO - Refraction Constants"> +<META NAME="keywords" CONTENT="sun67"> +<META NAME="resource-type" CONTENT="document"> +<META NAME="distribution" CONTENT="global"> +<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso_8859_1"> +<LINK REL="STYLESHEET" HREF="sun67.css"> +<LINK REL="next" HREF="node166.html"> +<LINK REL="previous" HREF="node164.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node166.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html2076" HREF="node166.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html2074" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html2068" HREF="node164.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html2077" HREF="node166.html">SLA_REFCOQ - Refraction Constants (fast)</A> +<BR> +<B>Up:</B> <A NAME="tex2html2075" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html2069" HREF="node164.html">SLA_RDPLAN - Apparent of Planet</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION0004152000000000000000">SLA_REFCO - Refraction Constants</A> +<A NAME="xref_SLA_REFCO"> </A><A NAME="SLA_REFCO"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Determine the constants <I>a</I> and <I>b</I> in the +atmospheric refraction model + <IMG WIDTH="164" HEIGHT="31" ALIGN="MIDDLE" BORDER="0" + SRC="img148.gif" + ALT="$\Delta \zeta = a \tan \zeta + b \tan^{3} \zeta$">, where <IMG WIDTH="11" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img149.gif" + ALT="$\zeta$"> is the <I>observed</I> zenith distance + (<I>i.e.</I> affected by refraction) and <IMG WIDTH="24" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img150.gif" + ALT="$\Delta \zeta$"> is + what to add to <IMG WIDTH="11" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img149.gif" + ALT="$\zeta$"> to give the <I>topocentric</I> + (<I>i.e. in vacuo</I>) zenith distance. +<P> <DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_REFCO (HM, TDK, PMB, RH, WL, PHI, TLR, EPS, REFA, REFB)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>HM</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP>height of the observer above sea level (metre)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>TDK</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>ambient temperature at the observer (degrees K)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PMB</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>pressure at the observer (mB)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>RH</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>relative humidity at the observer (range 0-1)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>WL</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>effective wavelength of the source (<IMG WIDTH="26" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img21.gif" + ALT="$\mu{\rm m}$">)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>PHI</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>latitude of the observer (radian, astronomical)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>TLR</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>temperature lapse rate in the troposphere +(degrees K per metre)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>EPS</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>precision required to terminate iteration (radian)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>REFA</EM></TD> +<TH ALIGN="LEFT"><B>D</B></TH> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="37" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img151.gif" + ALT="$\tan \zeta$"> coefficient (radians)</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>REFB</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP><IMG WIDTH="44" HEIGHT="31" ALIGN="MIDDLE" BORDER="0" + SRC="img152.gif" + ALT="$\tan^{3} \zeta$"> coefficient (radians)</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>Suggested values for the TLR and EPS arguments are 0.0065D0 and +1D-8 respectively. +<DT>2. +<DD>The radio refraction is chosen by specifying WL >100 <IMG WIDTH="26" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img21.gif" + ALT="$\mu{\rm m}$">. <DT>3. +<DD>The routine is a slower but more accurate alternative to the + sla_REFCOQ routine. The constants it produces give perfect + agreement with sla_REFRO at zenith distances + <IMG WIDTH="54" HEIGHT="16" ALIGN="BOTTOM" BORDER="0" + SRC="img153.gif" + ALT="$\tan^{-1} 1$"> (<IMG WIDTH="26" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img154.gif" + ALT="$45^\circ$">) and <IMG WIDTH="54" HEIGHT="16" ALIGN="BOTTOM" BORDER="0" + SRC="img155.gif" + ALT="$\tan^{-1} 4$"> (<IMG WIDTH="43" HEIGHT="14" ALIGN="BOTTOM" BORDER="0" + SRC="img156.gif" + ALT="$\sim 76^\circ$">). + At other zenith distances, the model achieves: +<P> <IMG WIDTH="23" HEIGHT="18" ALIGN="BOTTOM" BORDER="0" + SRC="img83.gif" + ALT="$0\hspace{-0.05em}^{'\hspace{-0.1em}'}\hspace{-0.4em}.5$"> accuracy for <IMG WIDTH="56" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img157.gif" + ALT="$\zeta<80^{\circ}$">,<P> <IMG WIDTH="31" HEIGHT="18" ALIGN="BOTTOM" BORDER="0" + SRC="img158.gif" + ALT="$0\hspace{-0.05em}^{'\hspace{-0.1em}'}\hspace{-0.4em}.01$"> accuracy for <IMG WIDTH="56" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img159.gif" + ALT="$\zeta<60^{\circ}$">, and +<P> <IMG WIDTH="39" HEIGHT="18" ALIGN="BOTTOM" BORDER="0" + SRC="img112.gif" + ALT="$0\hspace{-0.05em}^{'\hspace{-0.1em}'}\hspace{-0.4em}.001$"> accuracy for <IMG WIDTH="56" HEIGHT="27" ALIGN="MIDDLE" BORDER="0" + SRC="img160.gif" + ALT="$\zeta<45^{\circ}$">. </DL></DL> +<BR> <HR> +<A NAME="tex2html2076" HREF="node166.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html2074" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html2068" HREF="node164.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html2077" HREF="node166.html">SLA_REFCOQ - Refraction Constants (fast)</A> +<BR> +<B>Up:</B> <A NAME="tex2html2075" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html2069" HREF="node164.html">SLA_RDPLAN - Apparent of Planet</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<ADDRESS> +<I>SLALIB --- Positional Astronomy Library<BR>Starlink User Note 67<BR>P. T. Wallace<BR>12 October 1999<BR>E-mail:ptw@star.rl.ac.uk</I> +</ADDRESS> +</BODY> +</HTML> |