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The Australian Synchrotron is a 3 GeV synchrotron radiation facility built in Melbourne, Victoria and opened on 31 July 2007.[1][2] The circular building was designed by Architectus in conjunction with Thiess,[3] while the lattice design was performed substantially by Professor John Boldeman. The Synchrotron building is located in Clayton near the Monash University Clayton Campus.

The Australian Synchrotron is a light source facility (in contrast to a collider). It uses particle accelerators to produce a beam of high energy electrons which are placed within a storage ring that circulates the electrons to create synchrotron light. The light is directed down separate beamlines at the end of which may be placed a variety of experimental equipment contained within the endstations.

Accelerator systems
The interior of the Australian Synchrotron facility in 2006 before the beamlines were installed. Dominating the image is the storage ring, with an experimental endstation at front right. In the middle of the storage ring is the booster ring and linac.

Electron gun:
The electrons used to provide the synchrotron light are first produced at the electron gun, by thermionic emission from a heated metal cathode. The emitted electrons are then accelerated to an energy of 90 keV (kilo-electron volts) by a 90 kilovolt potential applied across the gun and make their way into the linear accelerator.

Linear accelerator:
The linear accelerator (or linac) uses a series of RF cavities, operating at a frequency of 3 GHz, to accelerate the electron beam to an energy of 100 MeV, over a distance of around 15 metres. Due to the nature of this acceleration, the beam must be separated into discrete packets, or 'bunches'. This bunching process is done at the start of the linac, using several 'bunching' cavities. The linac can accelerate a beam once every second. Further along the linac quadrupole magnets are used to help focus the electron beam.
Inside the booster ring shielding, the linac is visible at image right extending from the electron gun at the far wall, and joining into the booster ring seen at the left

Booster synchrotron:
The booster is an electron synchrotron which takes the 100 MeV beam from the linac and increases its energy to 3 GeV. The booster ring is 130 metres in circumference and contains a single 5-cell RF cavity (operating at 500 MHz) which provides energy to the electron beam. Acceleration of the beam is achieved by a simultaneous ramping up of the magnet strength and cavity fields. Each ramping cycle takes approximately 1 second (for a complete ramp up and down).

Storage ring:
The storage ring is the final destination for the accelerated electrons. It is 216 metres in circumference and consists of 14 nearly identical sectors. Each sector consists of a straight section and an arc, with the arcs containing two dipole 'bending' magnets each. Each dipole magnet is a potential source of synchrotron light and most straight sections can also host an insertion device, giving the possibility of 30+ beamlines at the Australian Synchrotron. Two of the straight sections are used to host the storage ring 500 MHz RF cavities, which are essential for replacing the energy that the beam loses through synchrotron radiation. The storage ring also contains a large number of quadrupole and sextupole magnets used for beam focusing and chromaticity corrections. The ring is designed to hold 200 mA of stored current with a beam lifetime of over 20 hours.

Vacuum systems:
The electron beam is kept within a very high vacuum at all times during the acceleration process and within the storage ring. This vacuum is necessary as any beam collisions with gas molecules will quickly degrade the beam quality and reduce the lifetime of the beam. The vacuum is achieved by enclosing the beam in a stainless steel pipe system, with numerous vacuum pump systems continually working to keep the vacuum quality high. Pressure within the storage ring is typically around 10−13 bar (10 nPa).

Control system:
Each digital and analogue I/O channel is associated with a database entry in a customised distributed open source database system called EPICS (Experimental Physics and Industrial Control System). The condition of the system is monitored and controlled by connecting specialised GUIs to the specified database entries. There are about 45,000 database entries (also known as process variables), most of which relate to the physical I/O. About 35,000 of these are permanently archived at intervals ranging from milliseconds to minutes. Some high level control of the physics-related parameters of the beam is provided through MATLAB which also provides data analysis tools and an interface with a computerised model of the accelerator. Personnel and equipment protection is achieved through the use of PLC-based systems, which also transfer data to EPICS. The Beamlines also use EPICS as the basis for their control.

Beamlines and experimental endstations
Soft x-ray beamline and endstation

Imaging and medical therapy
Infrared spectroscopy
Micro spectroscopy
Protein crystallography
Powder diffraction
Small and wide angle scattering
Soft X-ray spectroscopy
X-ray absorption spectroscopy


2009 governance crisis

An ongoing management crisis was set in motion following the sudden dismissal of the Australia Synchrotron's director, Professor Robert Lamb in late October 2009[4] . Professor Lamb, acknowledged as one of Australia's leading scientists[5] was artificially seconded to the synchrotron from his position as chair of chemistry at the University of Melbourne when the complex opened in July 2007 - He had transferred from the School of Chemistry at UNSW to the University of Melbourne in order to take the Synchrotron position. His dismissal without explanation by the Board of management led by the chair Ms. Catherine Walter, has caused the international Science Advisory Committee to the Australian Synchrotron to threaten to resign en masse and has resulted in a work-to-rule by the staff at the facility.[6][7]

Chair Catherine Walter has appointed former Australian of the Year, Sir Gustav Nossal as head of a new advisory body, the National Science Colloquium.[8] The body is not a replacement for the Scientific Advisory Committee, and Sir Gustav's appointment does not solve the current impasse between the beamline scientists and the Scientific Advisory Committee, and the Board. The Colloquium was formed (but not announced) before the crisis and as it was not ratified by the council of members is not a properly defined committee.

Following a meeting on December 9, 2009 with synchrotron staff, in which Ms Walter refused to resign, three members of the Scientific Advisory Committee resigned their positions.[9] A further two members have since resigned, with another indicating his intention[10] . The Scientific Advisory Committee are unhappy about the actions of Ms Walter, who has failed to heed their advice, concentrating too much on promoting a corporate culture, and lowered staff morale to an all-time low. The beamline scientists have also extended their work to rule indefinitely.[10] The CFO has also tendered his resignation, citing personal reasons.[11] The State Government of Victoria, which has the largest stake in the project, so far has declined to intervene.[12]

December 2010 update: Twelve months on from the dismissal of Professor Lamb, the total staff turnover increased dramatically with over thirty staff (from a total of just over one hundred) leaving during this period. This had been predominately from the non-scientific staff with flexible career options. This compares with just six staff in the twelve months before the 2009 crisis. Some who have left have been forced to do so (often at the instigation of the scientific staff) by the Human Resources Manager and required to sign confidentiality agreements under the threat of legal action. Others have resigned and left due to the favoritism and unethical behavior by senior management.

Additionally, despite an exhaustive international search, the position of facility director is without a permanent full time appointment. Professor Lamb remains with the University of Melbourne and has visited the Australian Synchrotron as a research user. The potential funding for further Beamlines has also been damaged as an indirect consequence of the Board's action.

In February 2011, Professor Keith Nugent was appointed as part time director (one day per week). Professor Nugent was previously a board member. A new position of Chief Operating Officer was created and filled by the previously acting director, Dr George Borg. [13]

2011 funding crisis

The synchrotron could be shut down in 2012 after the newly elected Victorian state government did not commit to ongoing funding of the research. [14] Further to this Kim Carr, Federal Minister for Innovation, Industry has stated "..it is a state responsibility and we cannot keep bailing it out forever..." in a letter to the Melbourne Age 12 May 2011 [15] responding to the Age's editorial the day before. [16] It has also been revealed that "facility's board of directors had made contingency plans for a funding cutoff." and that scientists are "hopeful rather than confident" that state and federal governments will reveal secure funding plans soon. [17]

Funding contributors
The Australian Synchrotron building

Victorian Government (Official Site)
Association of Australian Medical Research Institutes
Australian Nuclear Science and Technology Organisation (Official Site)
CSIRO (Australian Commonwealth Science and Industrial Research Organisation)
Monash University (Official site)
New Zealand (Official site New Zealand Government)
Queensland (Government site)
Western Australia (Government site)
Melbourne University (Official site)
New South Wales consortium
South Australia/La Trobe University(Official site) consortium


See also

List of synchrotron radiation facilities


References

^ Official Opening webcast timetable & archive site, 31 Jul 2007
^ "Scientists to unveil monster synchrotron", ABC News, 31 July 2007
^ Architectus and Thiess to Design Australian Synchrotron
^ Egan, Carmel (8 November 2009), "Stinkatron: chaos at the top", The Age (Melbourne)
^ Egan, Carmel (22 November 2009), "Synchrotron Board Mute on Crisis", The Age (Melbourne)
^ Egan, Carmel (29 November 09), "Scientists' rebellion to cripple synchrotron beam", The Age (Melbourne)
^ Egan, Carmel (6 December 2009), "Seven scientists at synchrotron issue ultimatum", The Age (Melbourne)
^ "Gus Nossal rides to the rescue of troubled synchrotron", The Australian, 1 December 2009
^ "Scientists walk out on Synchrotron", ABC News, 11 December 2009
^ a b Egan, Carmel (13 December 2009), "Out of sync", The Age (Melbourne)
^ "Glyn Davis demands answers from synchrotron", The Australian, 17 December 2009
^ Finkel, E. (1 January 2010), "Research Management: Protests by Staff, Advisers Rattle Australian Synchrotron", Science 327 (5961): 20, doi:10.1126/science.327.5961.20, PMID 20044547.
^ Australian Synchrotron announces senior appointments, 1 Mar 2010
^ "Synchrotron sinking as Baillieu pulls plug", The Sunday Age (Melbourne), 8 May 2011
^ "Record funding", The Age (Melbourne ), 12 May 2011
^ "Blinkered leaders leave researchers in limbo", The Age (Melbourne ), 11 May 2011
^ Australian Government Silent on Synchrotron Budget While Scientists Plan Expansion

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