Requesting MCenter Beam¶
If there was no beam before the start of your shift and you want to take beam, you need to coordinate this with the MCR. Instructions and information are on this page.
Preparing for beam¶
Beam may only be requested if MC7 has been search-and-secured and is interlocked. Ensure this is the case first (otherwise you will just be told no!). See 'MC7 interlocking' below.
In addition, we want the magnet to be turned on when we take beam. This ensures the particles are sent through the full beamline and into the detector. If the magnet is currently off, meaning the power supplies are powered down or the current is not set (look at the current in the synoptics monitoring -- see Synoptics Monitoring), it will need to be turned on and the current set to 1000A before requesting beam.
If the MC7 enclosure is interlocked and the power supplies are turned on, the current may be requested to be set by calling the MCR operators. See 'Requesting magnet current' below. If the power supplies are not turned on, they will need to be first. See 'Turning on the magnet power supplies' below.
If MC7 is interlocked, the magnet is on and the current is set to 1000A, we are good for beam! This may be requested by calling the MCR operators; see 'Requesting beam' below.
Beam may only be sent when the enclosure is in an 'interlocked' state. This means the MCR have 'searched-and-secured' the building, making sure there is physically no one there. They will set the interlocks during this process. This may be requested by calling MCR and requesting an MC7 search and secure.
Turning on the magnet power supplies¶
This may only be done once the MC7 enclosure if interlocked. It is an expert procedure which may be carried out by Alex, Yagmur or Mike. They will coordinate this procedure.
Request magnet current¶
The MCR will set our magnet current for us, if the power supplies are powered on. In order to request this, call the operator and ask for 'the current on magnet power supply MC7AN1 to be increased to 1000A'. They are used to dealing with these requests and will oblige. You can follow the progress on the synoptics page.
When stopping running with beam, we will need to turn the current down. Again, call MCR and ask them to turn the current on magnet power supply MC7AN1 down to 0.
There is no need to ask for changing the magnet current in steps any more, a hardware solution has been implemented at the power supply that limits the rate of change of current.
Beam is requested by calling the MCR and asking for MCenter beam. They will send it! There may be some reason why it can't be sent, so they will explain. They may ask how much we want. If we have a specific number in mind, we should tell them know that. If not, you can just ask for what we typically receive or the maximum they can give us!
You can typically request current be increased and beam turned on at the same time, and the same when turned both off.