First light in hutch 3B
The AS imaging and medical beamline has achieved ‘first light’ at the end of the transfer tunnel, extending the x-ray beam into the satellite building, 140 metres from the original x-ray source.
By the time it reaches the satellite building, the IM beam measures 4cm high by 50cm wide, making it the world's largest synchrotron beam.
This is a major achievement by AS staff, who have designed, constructed, installed and upgraded the required x-ray beam conditioning and filtering equipment, as well as a large-diameter, high-vacuum pipeline to safely and efficiently deliver the beam through the transfer tunnel to the satellite building.
Announcing the milestone, which was achieved on 18 September 2012, AS head of science Andrew Peele thanked all the staff involved and acknowledged their enormous efforts.
“This represents, I am reliably informed, the biggest beam in the world – although the beams on Jonathan McKinlay and Daniel Häusermann’s faces may be bigger.”
Photos above: principal IM scientist Daniel Häusermann (left) and principal mechanical engineer Jonathan McKinlay (right) show off the size of the x-ray beam (red outline on yellow tape) in the satellite building.(A good reason to claim that 'ours is bigger than yours', perhaps?)
What is the extended beamline for?
A major focus of the imaging and medical beamline is to enable high resolution, high contrast imaging of bio-samples to investigate, for example, micro-vascularisation in tumours, micro-structure in bones and, using fast dynamic imaging, in-vivo processes such as blood flow, breathing and changes in mucus layer. However, a large distance between the x-ray source and the sample is needed to obtain the required high contrast and resolution, and a very wide beam is needed to image large objects such as new born lambs, and human lungs.
Two years ago, AS staff embarked on the major challenge of designing in-house the ‘IMBL transfer line’. It is made up of the 'short' 20-metre transfer line (enclosures 1B to the transfer tunnel entrance) and a 'long' 100-metre transfer line (through the tunnel to enclosure 3B) to deliver the largest synchrotron beam in the world to date.
Construction and commissioning
Various components came from Australia (tubes and stands), Switzerland (flanges, bellows, gate valves), Germany (wide range vacuum gauges and controllers), Italy (ion pumps and controllers), the USA (radiation-resistant vacuum gauges) and Taiwan (flanges, bellows, other vacuum components).
Welding and assembly were done by AS staff, a major first for the AS as this is not only our first beamline designed, constructed and assembled in-house, but the largest x-ray beam transfer line in the world - by both diameter and volume.
Manufacturing of custom components began in September 2011 and onsite construction began in earnest in February 2012. On 18 September 2012, first light was delivered to the satellite building for testing the radiation shielding of the tunnel and satellite building bunkers.
Daniel Häusermann, principal scientist on the AS imaging and medical beamline team, said: “this is the most important IMBL milestone so far, and not so much for the technical and world first achievement as for the deep satisfaction that it gave the IMBL team and the dozens of support staff: mechanical and electrical technicians, mechanical and controls engineers, safety personnel, not forgetting the procurement and stores staff. Well done to all, this is truly a big success story for the AS and the development of in-house skills for future beamlines.
“We are also grateful to the National Health and Medical Research Council (NH&MRC) for the $13.2 million funding they provided for the extended beamline.”
Daniel said that IM beamline enclosure 3B would be tested on 2 October 2012, and that commissioning of the long beamline with its high resolution imaging program would begin immediately after this date to be ready for the first users on 6 November 2012.
Some facts and figures
- 25m3 of evacuated volume with a diameter of 25cm to 60cm
- 100m of TIG welding, all done in-house and without a single leak
- Several gate valves for maintenance and addition of beamline components, the largest - for the 60cm diameter section - weighing half a tonne and needing 7 seconds to open or close (smaller valves take 0.5 second!)
- 13 ion pumps with a total pumping capacity of 6500l/s achieving a working vacuum of 3x10-8 mbar
- The largest beryllium window on a synchrotron beamline, designed and assembled by AS engineers
- Total equipment cost of $0.9 million.