The CRG beamline D2AM is located at the bending magnet D2 of the ESRF synchrotron. The beamline consists of an Optical Hutch working with the white beam to produce the monochromatic beam used in the Experimental Hutch with various experimental settings.

 

Note temporarely, plc and fluo screen are out of order, only the command in spec are working... (openVanne1, closeVanne1, ..., openFluo to remove it , closeFluo to put it in the beam, shopen, shclose)

Overview of the beamline Optic

A view of the Optical Hutch is available here. The first part of the beamline is the white beam shutter which is located inside the ESRF ring wall. Then at the entry of the Optical Hutch a beam LIMITOR has been designed to define a 3mrad horizontal beam divergency. This beam limitor is located in the first vacuum vessel.

The next vacuum vessel contains 2 filters holders ( ATTENUATOR ) and the first slits system ( SLITS 1 ), which allows to set the vertical and horizontal divergence of the incoming beam. This vessel is followed by the 1st mirror, the monochromator, and the 2nd mirror. The beam is kept under vacuum up to the instrument in the Experimental Hutch going through a 2nd slit system ( SLITS 2 ), used to clean the monochromatic beam, the secondary beam shutter and a 3rd slit system ( SLITS 3 ) located in a small hutch between the Experimental Hutch and the Optical Hutch.

Schematic of the optic design. Indicated distances refer to the source.

Vacuum system

The users may have to close the 3rd valve (V3) to change the filters or to exchange the pipes.

Jvacuum_appli

  • close the RV6 valve in the Jvacuum_appli or with the command closeRV6 in spec
  • close the by-pass in the experimental hutch (green handle)
  • open the leak
  • fix your pipes or filters
  • close the leak
  • pump with the turbomolecular pump on the sideboard
  • check you have no leak, by closing the pump valve and reopening it
  • open gently the by-pass as soon as the vacuum is in the 10⁻³ mbar range
  • wait until the RV6 valve drawing become green on the Jvacuum_appli (careful it takes few hours !)
  • open RV6 (Jvacuum_appli or openRV6 in spec)

 

In case of troubles, call the local contact.

 

Opening the White Beam Shutter.

The main shutter of the optical hutch can only be open if the following requirements are satisfied :

  • open idappli by typing "idappli" in a standard linux window. You need to enter a password (if not call the local contact). You will find on this window two buttons open FE or close FE.
  • verify that the optical hutch is interlocked
  • verify that the beam is ready (green) for delivery (user mode) in the idappli application
  • verify that all the valves are open (green) on the Jvacuum_appli

An AUTOMATIC MODE can be triggered, but MIND , if you forget it, your FRONT END will AUTOMATICALLY close itself after 72 hours

!!!

In case of troubles, call the local contact.

 

Opening the Monochromatic Beam Shutter :

This is done through the Jvacuum_appli (clicking on the Safety Shutter 1 drawing) or directly inside SPEC applications with the commands: "shopen" or "shclose".

Clues to find the beam

Here are a few points to check if you have no beam in the experimental hutch:

  • beam is down : check the ring current in the idappli window
  • check that the front end is open (it can be closed when automatic mode is over)
  • check that the experimental shutter is open and all the vacuum valves between the optic and the experimental hutch (Jvaccum_application or green light next to the door)
  • check that filters are not on (red lights on the black modulus of the min rack)
  • check that the CCD rapid shutter is not closed (openCCDsh)
  • check that the PM are well connected