HARPSpol: Testing and Commissioning at La Silla
Landing in Santiago on May 18th, 2009
Small telescopes on La Silla (View from the optical lab)
Helpful ESO people thinking how to rotate our motors (Ismo and Gaspare)
Andrey at his best: assembly
Ready to go ... almost
It is tight in the Cassegrain adaptor. The rectangular indentation at the bottom right is the mounting place for our polarimeter
Sunset before the first observing night
In the RITZ control room. On the left: Gaspare, Michiel, Frans. On the back Alain and Andrey is on the right
Our largest problem so far was the ESO controller cannot to our stepper motor that rotates the retarder plates. Fortunately, thanks to heroic efforts by Michiel and Frans, we managed to use a simple demo board that I bought for rotating the motor in the lab. We are going to use it for now on the telescope.
The board that saved the day
And now we are ready – going to observe tonight, May 25th, 2009
Mounting the HARPSpol in the Cassegrain adaptor
Final inspection: one is working while three are watching Andrey (left) and Gaspare: don't you find certain similarity?
Our little controller board found a place … but communicating with it was non-trivial
Lifting and bolting to the telescope meanwhile clouds started creeping in
Finally the first commissioning night was lost to the bad weather. We did lots of calibrations and took two very poor spectra of α Cen in circular polarization. We hope for better luck the next night.
So far only bad luck: during the commissioning and the first two regular observing nights the La Silla observatory looked like this:
We are hopeful for tonight though…
Finally, first observations:
A fragment of a
high-resolution spectrum of a magnetic CP star HD 137509. Black line -
green line - circular polarization, blue line - so-called null spectrum showing uncertainty in the polarization.
… and some happy observers:
Gamma Equ in all Stokes parameters. The S/N is about 130. From top to bottom: I, U, Q and V. The bottom line is the null-spectrum.
As usual, more soon...