In the week of the 9th of December 2019 we had the opportunity to measure a “MIEZE” signal within a SANS measurement -> MISANS. With this technique we are able to look into the self-diffusion of water. So within the SANS signal of the water we find a dynamic signal that related to the movement of water.
This MISANS mode is slightly different than the last MIEZE measurement. This time we used the RF flippers in a Pi/2 and 1/t (no gradient) setting so there was no need to use the Vcoils. As the neutron intensity variation stayed below 100kHz we could just use the SANS (He3) detector in combination with the standard SANS vessel. So no major rebuild was needed, only a few hours tweaking.
Here the H3 Analyser is being installed. Magnets are perpendicular with maximum distance to each other
Thanks to the ISIS He3 team we could analyse the beam at these small angles (around 5 deg) with very low background.
Again this was a collaboration with people from FRM2 in Munich, TU Vienna, ISIS, Indiana University Bloomington and TU Delft.
Recently a very nice paper appeared with significant contributions from SESANS on Larmor and Delft. It is about understanding how colors in nature are produced and with the goal to produce better paints
On the 27th of August a group of 13 traveled to ISIS to participate in the celebration of the closure of the Larmor project. In the evening there was a diner at the Cosener’s house in Abingdon. The next day group of first day users of the instrument presented their results in a mini symposium.
Two re-presenters of NWO were present and witnessed a classy opening of the facility by Lucas van Vliet, dean Applied Sciences and Bert Wolterbeek, director of the Reactor Institute at TU Delft.
On the right we have a nice group photo next to the shielded blockhouse of Larmor with all the dutch participants together with our ISIS collaborators within the project.
This is Robert Dalgliesh who was the project leader on the ISIS side of the project. His endurance and patience made the project into a success, many thanks to him…
On the left a picture of Katia Pappas presenting the spin-echo angular encoding of SESANS in the min-symposium. She has been the project responsible and also one of the first users looking at skyrmions on Larmor.
On Thursday 11th October 2018 we have produced and measured the very first TOF MIEZE signal on LARMOR!
With this MIEZE mode it is possible to measure dynamics in a sample (0.1ns -10ns). This mode gave us great challenges during the design phase as it was very demanding on the electronics of LARMOR instrument. It was truly very exciting to finally see the very first modulations on our screen appear (left).
First arm converted to a MIEZE arm
First MIEZE signal with 413 KHz modulation
On the right one can see the the fist arm of the LARMOR instrument that for this occasion is converted into a MIEZE configuration with two Vcoils and two RF flippers running at different frequencies. The highest MIEZE modulation frequency reached and measured was 1.03 MHz!
In only 4 days (and nights) we have completely commissioned the MIEZE mode!
The two MIEZE detectors, the blue is from FRM2 and the Al in front is from ISIS
This demanding schedule was only possible due to a good preparation of Niels Geerits who completed his Master project in Delft building a copy of the instrument and gaining months of experience. This together with the great help and expertise of Cristian Franz, who is the MIEZE expert at RESEDA at the FRM2 in Munich. He also brought a essential piece of kit, a very fast detector, see right (blue), that is able the measure the very fast modulation signals (up to 1 MHz) in TOF. An alternative fast detector was made available by Davide Raspino from ISIS that also appeared very imported for the success of the experiment. Summarize, it was a great team effort of ISIS, our FRM2 collaboration and Delft that made everything come together and produce an excellent commissioning experiment.
The collaboration between TU Delft and ISIS has recently delivered a new high angle bank for Larmor which has now been used for the first time June 2018. The Figures below show preliminary results of a simultaneous SANS and diffraction study of in-situ precipitate growth that is coupled to the phase transformation kinetics in steel (by the group of Erik Offerman TU-Delft).
. time resolved SANS time resolved Diffraction
LARMOR is a neutron scattering instrument that is now partially financed by a "NWO groot" grant and is been built at the UK neutron source ISIS. The basis is a competitive future proof SANS instrument fully paid, developed and run by ISIS. The Dutch contribution will significantly increase its functionality by exploiting a broad range of Larmor labeling methods in the space and time domain.