Institut für Astronomie und AstrophysikAbteilung AstronomieSand 1, D-72076 Tübingen, Germany |
binarycor,time,asini=asini,porb=porb,eccentricity=ecc,omega=omega_d, $ t90=t90,t0=t0, pporb=pporb,limit=limit,maxiter=maxiter
time : event time (MJD)
asini : Projected semi-major axis [lt-secs], Mandatory porb : Orbital period at the epoch [days], Mandatory eccentricity : Eccentricity, (0<=e<1) omega: Longitude of periastron [degrees], mandatory the epoch is given by one of the following: T0 : epoch for mean longitude of 0 degrees (periastron, MJD) T90 : epoch for mean longitude of 90 degrees (MJD) T90 and T0 have to be in days and in the same time system as time (e.g. JD or MJD) Circular orbits: * if time of lower conjunction Tlow is known, set T0=Tlow and omega=0 * if time of ascending node is known, Tasc, set T90=Tasc and omega=0 * if time of mid eclipse is known, Tecl, set T0=Tecl-0.25*porb and omega=0
pporb: rate of change of the orbital period (s/s) limit: absolute precision of the correction of the computation (days, default: 1D-6) maxiter: stop Newton-Raphson iteration after maxiter steps if limit is not reached (default: 20)
time is updated to the time in the barycenter of the double star
For each time, the z-position of the emitting object is computed and the time is adjusted accordingly. This is iterated until convergence is reached (usually only one iteration is necessary, even in high elliptic cases, Follows equations from Hilditch's book and has also been checked against fasebin/axBary. All codes give identical results, (to better than 1d-7s) as checked by a Monte Carlo search using 1d7 different orbits.
$Log: binarycor.pro,v $ Revision 1.6 2006/03/31 10:42:29 wilms corrected instructions for circular orbits (prompted by Dmitry Klochkov) Revision 1.5 2005/05/14 20:46:39 wilms removed special case for circular orbits since this used different conventions for the orbit zero point. For this version of the code, results for ecc=epsilon and ecc=0 will be the same. Unfortuntely this breaks the backwards compatibility. Revision 1.4 2005/05/14 13:43:32 wilms Corrected erroneous computation of mean anomaly for eccentric orbits. Revision 1.3 2005/02/23 09:46:22 wilms removed redundant check for t90/t0 Revision 1.2 2005/02/18 20:40:33 wilms * added proper treatment of t90 for elliptical orbits * cleaned up the equations for elliptical orbits (removed excessive parentheses) Revision 1.1 2004/08/05 12:27:50 wilms rewrite of dblstarcor, orbital elements now given as keyword parameters, several speed-ups, further consistency checks. Verification that the equation for z is correct. Revision 1.3 2002/09/09 14:58:27 wilms removed debugging statement; several cosmetic changes Version 1.0, 1997/01/09, Deepto Chakrabarty, Caltech/MIT Version 1.1, 1999/11/11, Patrick Risse IAAT - Include the optional Input of pporb - abort criteria for the iteration
[Home Page] [Software, Documentation] [IDL Documentation] [Quick Reference] [Feedback]