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HI Alexandre,

Thanks for your response.

Ok for the resolution of 75.000, I will correct the graph but in fact it's a good news, the ESP resolution should be better than 30.000. The resolution indicated by the soft treatment is underestimated.

Thanks also for the HARPS spectra

Next step, Exo-planet detection

Hi Olivier,

If the P-cygni profile of Halpha match fairly well between SOPHIE or even HARPS-N and ESP, it does not mean the spectral resolution of ESP is as high as 75k or 110k. It just means the H-alpha profile is broad enough that it is not dominated by the resolution of the spectrograph. Even if you had a spectrum with a resolution of a few million, your plot will look like almost the same.

Take a spectrum of the Sun and compare the width of weak lines between ESP and SOPHIE / HARPS-N and you will felt the difference in resolution.
By the way, 30k is already much higher than most of the VLT spectrographs (e.g. GIRAFFE, FORS2, X-SHOOTER).

The next step is however not the detection of exoplanets, but the characterisation of its radial velocity precision. Two steps from now, but only two.

Dear Olivier,
I visited again this side with your "first class" spectra. As you can imagine, I am interested in the spectrum of zeta Tau from 19/03/2016.
The spectrum of P Cyg has no date reference but I assume it's from 09/06/2016, which you sent already, right?

Best wishes, Ernst

Some news about ESP spectrograph:

- New calibration response process in ISIS software order by order from 48 to 84

- I have process some change in file lines.lst to add more lines, remove some blend lines and add new values with 4 digits after dot.

I can now process in one time all order from 48 to 84 (4056 Å to 7190 Å)

The gaol now is to reduce more orders (from 42 to 88) covered a range of 3850 Å to 7600 Å in one time.

Here's a comparaison between AOV star in Pickels data base (in red) with Vega spectrum (ESP spectrum) correct with the RI (in blue)

New spectrum taken with ESP Spectrograph : Del Sco

My goal is to increase the number of order process with ISIS in the blue, but it's difficult because the flux is very low in the blue. I have to take more exposure....

The full spectrum (37 orders merged), the signal in the blue is noisy SNR about 10)


And order 52 : H Alpha (SNR about 150)