blob: b0e2773ec1ea93701c16ac988d240d4452a9065f (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
.help rvgalc Jun99 "Slalib Package"
.nf
REAL FUNCTION slRVGA (R2000, D2000)
- - - - - - -
R V G A
- - - - - - -
Velocity component in a given direction due to the rotation
of the Galaxy (single precision)
Given:
R2000,D2000 real J2000.0 mean RA,Dec (radians)
Result:
Component of dynamical LSR motion in direction R2000,D2000 (km/s)
Sign convention:
The result is +ve when the dynamical LSR is receding from the
given point on the sky.
Note: The Local Standard of Rest used here is a point in the
vicinity of the Sun which is in a circular orbit around
the Galactic centre. Sometimes called the "dynamical" LSR,
it is not to be confused with a "kinematical" LSR, which
is the mean standard of rest of star catalogues or stellar
populations.
Reference: The orbital speed of 220 km/s used here comes from
Kerr & Lynden-Bell (1986), MNRAS, 221, p1023.
Called:
slCS2C, slVDV
P.T.Wallace Starlink 23 March 1994
Copyright (C) 1995 Rutherford Appleton Laboratory
Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
.fi
.endhelp
|
