Units of flux

[SCO]

Just a quick question.. The Y axis on my plot shows the title: rel_flux_T1 x(1) - 0.02 (normalized). I am not sure I understand the meaning of that. Could you please explain what that means, what units the change in flux are measured in, and how to convert them to units of change in magnitude? For example, if the plot shows a horizontal line at 0.90 and another one in 0.95, that is certainly a change of 0.05. But 0.05 what? Lumins, 1/10 Lumin, 1/100 Lumin? And would the formula to convert this difference in to difference in magnitude be the one shown below that is used by SDSS? The reason I am asking this is that I want to cross-check the results I get with current documentation. Thanks.

[karenacollins]

Relative flux is simply the flux of the target star divided by the total of the flux of the comp stars. If you want normalized relative flux, enable a "Norm/Mag Ref" mode in the Y-data panel (with "Out Mag" disabled). Normalize relative flux is then a fractional flux change (i.e. a change of 0.01 is 1%). If you want relative magnitude change, then enable a "Norm/Mag Ref" mode and also "Out Mag" in the y-data panel. Then the units changes are in magnitude. Units of mmag can be output by also adjusting "Y x 1E" on the Multi-plot Y-data panel from 0 to +3.

Karen

[SCO]

Thanks Karen, that is very helpful.

Ed