LARMOR

On the 17th of March LARMOR woke up after a long shutdown. Please follow the witter for the hot news on the commissioning! Intensity is as expected, background needs a bit more work.

The new guide field profile has a winding tool to fix the copper wire, hope it will work. We will make a new prototype coil soon…

On December 17th 2014 we had an important stakeholders meeting in Delft. All the partners in the proposal were present.

We started of with several presentations that give an update or start a discussion. First there was a presentation of Rob Dalgliesh that gives an impressive overview of the progress on the SANS instrument at ISIS.

After that Jeroen Plomp gave an Delft progress update.

Next was Jurrian Bakker, who is our soft matter PhD student, with the update on Delft_soft matter PhD.

The last presentation was for our newest member of the team, Fei Li, who is our hard matter PhD student, with an update on Delft_hard matter PhDFei.

After these presentation we had discussion on sample environment, Larmor Diffraction mode, new detector to combine SANS and diffraction, use of beam time and many other topics.

At the moment components for our prototype are coming in. We are working on the alignment of the rail system that guides the magents up and down the beamline. An other team is working on electronic motion control of this movement. We have one full ISIS motion control system (thank you Steven!) to play with…great fun!!!

Following the previous post about guide field calculations, here we have a prototype of the new guide coil design. We will have special custom extruded Al profile with ITEM profile on the inside, protection plate connection on outside, room for Cu cooling tube, 3D printed corners to reduce price and have smooth wire feed-in/out.

This prototype was tested up to 10 A and 100 Watt (approx. 80 ‘C), no cooling.

Simulations have been done for many configurations of the coils that guide the precession through the instrument. For the SESANS mode these coils need to be in a magnetic balance for the full beam cross section. This is not trivial because of all the spacial restrictions in the instrument. On the left one can see the SESANS configuration (all coils in line) with a coil for the first arm, sample position and second arm. On the right one can see the magnetic field on the central axis of the instrument. Below a colorful plot of this field for the full setup.

Together with Tomas M. from ISIS we have been looking for the optimal setting of our split magnets. Depending on the encoding angle (plot 1=80 deg, plot 2=20 deg) we need a certain shift of the pole shoes. Michel T. is digging through all the simulation data to find the perfect setting. Conclusion: it will probably work fine…

To avoid any errors in our design and to get all the cables at the right length we made a wooden copy of the most important ISIS hardware on the two LARMOR tables. The next step is the Delft magnets and motion control and then we can practice the transfer from SANS to SESANS…

Four meters of brute power…

The RF AR-800 amplifiers are ready for testing…

If they pass the test we can already ship two pieces to ISIS for installation and test if it will add noise to the detector for example.

Installation of the Delft equipment on the LARMOR instrument at ISIS needs to be plug and play. To be sure this will be a smooth installation we have now the exact same tables. With this we can even practice the alignment procedure of the magnets and check what is the best way to run all the cables. One striking point…LARMOR tables are massive, next challenge is to find the space to put these in line…

The first picture shows the two tables with our 3D printed scaled model on top. The second picture shows the first table. We have added side support, at ISIS this table is bolted to the ground. Third picture shows the table that will hold the detector/SANS vessel and our magnets. The strips support the reference plane that will hold our translation stages.