The command irv has a few specific options to select and plot radial velocities in function of observation time or Julian date. The option -dn was made to look at the observations of each night to check visually the stability of the radial velocity system. The option -v is used to plot the radial velocities of a star in function of the Julian date and -bin is used to extract the observations of one star and start the program to determine an orbit. These actions are grouped in the menu sbs. The program is described in part III.
> ngc 2516
> irv -dn produce a list of the observing nights, ordered by increasing Julian dates, with a minimum of 5 observations. These nights are numbered for display and plotting facilities.
Which night number? 5
Do you want to plot the RVs? y
What do you want to do? m
Give the mean cluster RV: 15
What do you want to do? f
Which night number? 0
The level of selection may be modified by entering the new limit:
> irv -dn 10
The rest of the process is the same as the one described just above.
> irv -v 5 select the observations relating to star 5 and plots the data versus the Julian dates.
Do you want to plot the RVs? y
What do you want to do? m
Give the mean cluster RV: 15
What do you want to do? f
> irv 5 | page pipe with page or more for long output
> irv jd -eq 40191 select and display the observations made on JD 24440191.
> irv -bin 25 select the measurements of star 25 and run the program to compute the binary orbit, for a SB1
> irv -bin2 34 select the measurements of star 34 and run the program to compute the binary orbit, for a SB2