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author | Joseph Hunkeler <jhunkeler@gmail.com> | 2015-03-04 21:21:30 -0500 |
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committer | Joseph Hunkeler <jhunkeler@gmail.com> | 2015-03-04 21:21:30 -0500 |
commit | d54fe7c1f704a63824c5bfa0ece65245572e9b27 (patch) | |
tree | afc52015ffc2c74e0266653eecef1c8ef8ba5d91 /src/slalib/rvlsrk.f | |
download | calfuse-d54fe7c1f704a63824c5bfa0ece65245572e9b27.tar.gz |
Initial commit
Diffstat (limited to 'src/slalib/rvlsrk.f')
-rw-r--r-- | src/slalib/rvlsrk.f | 77 |
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diff --git a/src/slalib/rvlsrk.f b/src/slalib/rvlsrk.f new file mode 100644 index 0000000..b484fe8 --- /dev/null +++ b/src/slalib/rvlsrk.f @@ -0,0 +1,77 @@ + REAL FUNCTION sla_RVLSRK (R2000, D2000) +*+ +* - - - - - - - +* R V L S R K +* - - - - - - - +* +* Velocity component in a given direction due to the Sun's motion +* with respect to an adopted kinematic Local Standard of Rest. +* +* (single precision) +* +* Given: +* R2000,D2000 r J2000.0 mean RA,Dec (radians) +* +* Result: +* Component of "standard" solar motion in direction R2000,D2000 (km/s) +* +* Sign convention: +* The result is +ve when the Sun is receding from the given point on +* the sky. +* +* Note: The Local Standard of Rest used here is one of several +* "kinematical" LSRs in common use. A kinematical LSR is the +* mean standard of rest of specified star catalogues or stellar +* populations. The Sun's motion with respect to a kinematical +* LSR is known as the "standard" solar motion. +* +* There is another sort of LSR, the "dynamical" LSR, which is a +* point in the vicinity of the Sun which is in a circular orbit +* around the Galactic centre. The Sun's motion with respect to +* the dynamical LSR is called the "peculiar" solar motion. To +* obtain a radial velocity correction with respect to the +* dynamical LSR use the routine sla_RVLSRD. +* +* Reference: Delhaye (1965), in "Stars and Stellar Systems", vol 5, +* p73. +* +* Called: +* sla_CS2C, sla_VDV +* +* P.T.Wallace Starlink 11 March 1994 +* +* Copyright (C) 1995 Rutherford Appleton Laboratory +*- + + IMPLICIT NONE + + REAL R2000,D2000 + + REAL VA(3), VB(3) + + REAL sla_VDV + +* +* Standard solar motion (from Methods of Experimental Physics, ed Meeks, +* vol 12, part C, sec 6.1.5.2, p281): +* +* 20 km/s towards RA 18h Dec +30d (1900). +* +* The solar motion is expressed here in the form of a J2000.0 +* equatorial Cartesian vector: +* +* VA(1) = X = -SPEED*COS(RA)*COS(DEC) +* VA(2) = Y = -SPEED*SIN(RA)*COS(DEC) +* VA(3) = Z = -SPEED*SIN(DEC) + + DATA VA / -0.29000, +17.31726, -10.00141 / + + + +* Convert given J2000 RA,Dec to x,y,z + CALL sla_CS2C(R2000,D2000,VB) + +* Compute dot product with solar motion vector + sla_RVLSRK=sla_VDV(VA,VB) + + END |