$\star$ Propagation of zero points by the charts of quantum effectiveness

To propagate zero points ELIXIR, it is necessary for us thus to set out again of the charts of relative quantum effectiveness of each CCD In practice, we discovered the supernovæ in the CCD 4 and 10. The propagation for the CCD 4 is thus very simple, it is enough to take into account the gain.

For the CCD 10, we submitted the relationship between the charts of quantum effectiveness which we applied to the images and those which were used during the estimate of zero points ELIXIR. Then we added the term of gain.

Our zero point is written finally:

$$zero_{image} = zero_{ELIXIR} - 2.5\log_{10}(flat_{elixir}/flat(ToADS)) - 2.5\log_{10}(gain)$$ (8.18)