Accelerator Systems Overview
This page contains some of the technical data relating to the accelerator systems at the Australian Synchrotron.
Storage Ring
The Australian Synchrotron is a light source with a 3 GeV electron storage ring with an average current of 200 mA and a circumference of 216 meters (about twice the length of a football field). The lattice (magnetic design) is a Chasman-Green design repeated 14 times to form the storage ring.
| Parameter | Value |
| Energy (E) | 3.03 GeV |
| Rel. Gamma (γ) / Brho (Bρ) | 5935 / 10.12 |
| Average Current (I) | 200 mA |
| Maximum Single Bunch Current (Isb) | 10 mA |
| Maximum Peak Current (Ipk) **** | 300 A |
| SR Circumference (C) | 215.991 m |
| SR Revolution (frev) | 720.467 ns (1.38799 MHz) |
| Energy Spread (σE) | 1.027e-3 |
| Energy Loss (dipole only) *** | 932 keV/turn (186 kW @ 200 mA) |
| Cavity Voltage | 2000 kV |
| Cavity Frequency | 499.677 MHz |
| Cavity Power (3 cavity op) | 140 * 3 = 420 kW (150 kW unavailable due to wall losses @ 600 kV) |
| Synchronous Phase | 2.66354 rad |
| Linear Energy Acceptance | 1.47 % |
| Bunch Length (σz) | 29.36 ps (8.801 mm) |
| Momentum Compaction (αc) | 0.00211 |
| Synchrotron Tune (νz) | 0.00847 (11.757 kHz, 118 turns) |
| Parameter | Horizontal | Vertical |
| Tunes (νx, νy) | 13.29 | 5.216 |
| Chromaticity (ξx, ξy) | 1 | 1 |
| Emittance (εx, εx) | 10.51 nm | 0.13 nm (1.24% coupling)* |
Dipole 1 (7 degree source; beamline source)** | ||
| Beam Size (σx, σy) | 89.14 um | 65.74 um (1.24% coupling)* |
| Beam Divergence (σx', σy') | 179.4 urad | 6.556 urad |
Dipole 2 (6 degree source; XDB)** | ||
| Beam Size (σx, σy) | 88.01 um | 65.59 um (1.24% coupling)* |
| Beam Divergence (σx', σy') | 178.2 urad | 6.996 urad |
Straight | ||
| Beam Size (σx, σy) | 322.9 um | 17.81 um (1.24% coupling)* |
| Beam Divergence (σx', σy') | 34.33 urad | 7.355 urad |
* Estimated values based on coupling values derived from a LOCO fitted model of our current golden configuration
** Source location is negative 7 degrees from the upstream straight (Beamline sources are mostly from this dipole). Dipole 2 can also be used and is negative 6 degrees from the downstream straight.
*** energy_loss_in_eV_per_turn x average_beam_current = energy_loss_in_watts
**** I_pk = I_sb * R / bunch_length * sqrt(2*pi). Calculated for 10 mA in low alpha operation where the bunch length is ~10 ps (3.0 mm).
Insertion Devices (ID)
The storage ring has many distinct types of insertion devices such as permanent magnet wigglers (PMW), superconducting magnet wigglers (SCW), APPLE2 undulator, in-vacuum undulators (IVU), superconducting magnet undulators (SCU), cryogenic permanent magnet undulators (CPMU). The properties of these IDs are listed below.
| ID | ID Type | Mag. Gap (mm) | Mag. Len. (m) | Period (mm) | Eph † (eV) | Peak Field (T) | K | Max. Phase Error (deg) | Radiation Power (kW) | Beamline |
| 02 | SCU | 8.0 | 1.7 | 16 | 2349 | 1.084 | 1.62 | < 4.5 | 2.2 | Bio-SAX |
| 03 | IVU | 6.6 | 3 | 22 | 4700 | 0.85 | 1.77 | < 2.4 | 2.6 | Protein Crystallography (MX) |
| 04 | IVU | 5.7 | 3 | 17.5 | 2600 | 0.826 | 1.35 | < 3.0 | 2.4 | Protein Crystallography (MX3) |
| 05 | IVU | 5.5 | 2 | 22 | 4000 | 0.96 | 1.97 | < 2.4 | 2.1 | X-ray Fluorescence (XFM) |
| 08 | SCW | 15.2 | 1.55 | 52 | 25000 | 4.2 | 20.4 | | 37.5 | Imaging and Medical (IMBL) |
| 09 | CPMU | 5.7 | 3 | 19 | 1526 | 1.127 | 2.0 | < 3.0 | 4.4 | Nano-probe |
| 10 | SCW | 8.0 | 2.02 | 48 | 28696 | 4.7 | 20 | | 46.2 | Advanced Diffraction and Scattering (ADS) |
| 12 | PMW | 14.0 | 2 | 100 | 11400 | 1.90 | 17.7 | | 8.2 | X-ray Absorption (XAS) |
| 13 | IVU | 6.6 | 3 | 22 | 4700 | 0.85 | 1.77 | < 2.4 | 2.6 | Small Angle Scattering (SAX) |
| 14 | APPLE2 | 16.0 | 2 | 75 | 84 | 0.72 | 5.04 | < 2.7 | 1.1 | Soft X-ray (SXR) |
† For IVUs: 3rd harmonic. For APPLE: 1st harmonic. For wigglers it is the critical energy.
Injection System
The electrons are sourced and delivered to the storage ring by the 3 GeV electron injector that consists of two electron accelerators: 100 MeV Linac and a 3 GeV Booster Synchrotron.
The basic design parameters of the 100 MeV Linac are found in the table below.
| Parameter | Value |
| RF Frequency [MHz] | 2998 |
| Max. Repetition rate [Hz] | 5 (limited by gun) |
| Pulse Duration [ns] | 1 / 140 (single/multi bunch modes) |
| Energy [MeV] | 103 |
| Energy Spread [%] | 0.7 |
| Energy Variation [%] | < 0.5 |
| Normalised Emittance [mm mrad] | 48 π mm mrad |
| Total Charge [nC] | 0.48 / 4.8 (single/multi bunch modes) |
The 3 GeV booster synchrotron is a fourfold symmetric FODO lattice design with basic design parameters listed in the table below.
| Parameter | Injection | Extraction |
| Energy [GeV] | 0.1 | 3.0 |
| Circumference [m] | 130.2 | |
| Period [ns] | 434.3 | |
| Tunes | 9.2 / 3.23 | |
| Natural Chromaticity | -8.83 / -11.5 | |
| Beam Current [mA] | 5 | |
Synchrotron Radiation Parameters | ||
| Loss per turn [keV] | 0.0009 | 743 |
| Radiation @ 5 mA [kW] | 0 | 3.7 |
| Emittance [nm] | 0.04 | 33 |
| Horizontal Damping [ms] | 72 | 2.7 |
| Vertical Damping [ms] | 93 | 3.5 |
| Longitudinal Damping [ms] | 54 | 2.0 |
RF Parameters | ||
| Energy spread [%] | 0.0031 | 0.094 |
| Bunch Length [mm] | 0.3 | 19 |
| RF frequency [MHz] | 499.654 | |
| Harmonic | 217 | |
| RF Voltave [MV] | 0.12 | 1.2 |
| Sychrotron Frequency [kHz] | 184 | 100 |
Magnets and Power Supplies (inc. Pulsed systems)
The table below shows the parameters for pulsed magnets in the injection system.
| Parameter | Inj. Kicker | Inj. Septum | Ext Kicker | Ext Septum |
| Design kick [mrad] | 18.0 | 139.1 | 4.9 | 120.0 |
| Design field [G] | 59 | 455 | 500 | 7880 |
| Design Current [A] | 480 | 630 | 958 | 9456 |
| Length [m] | 1.0 | 1.02 | 1.0 | 1.52 |
| Peak Field [G] | 80 | 700 | 600 | 10,000 |
| Peak Current [A] | 650 | 970 | 1150 | 12,000 |
| Peak Voltage [V] | 2100 | 15 | 43,000 | 300 |
| Operating Point | 9.620 kV | 563.3 A | 19.620 kV | 8980.6 A |
| Pulse Len./Flat. [ns] | 150 (FT) | 3000 (L) | 150 (FT) | 600,000 (L) |
| Pulse Rise/Fall [ns] | 190 (Fall) | - | 300 (Rise) | - |
| Power Supply | 0.8kA/2.3kV PFN | 975A/20V Full Sine | 1.2kA/40kV PFN | 12kA/300V Full Sine |
| Inductance [uH] | 0.7 | 1.4 | 2.7 | 2.1 |
The table below shows the parameters for pulsed magnets in the storage ring.
| Parameter | Septum SEI-3 | Pre-Septum SEP-3 |
| Design kick [mrad] | 123.9 | 87.3 |
| Design field [G] | 8000 | 8000 |
| Design Current [A] | - | - |
| Length [m] | 1.573 | 1.108 |
| Peak Field [G] | 10000 | 10000 |
| Peak Current [A] | 12000 | 12000 |
| Peak Voltage [V] | 310 | 220 |
| Operating Point | 8303 | 8005 |
| Pulse Len./Flat. [us] | 600 (L) | 600 (L) |
| Pulse Rise/Fall [us] | - | - |
| Power Supply | 12kA/310V Full Sine | 12kA/220V Full Sine |
| Inductance [uH] | 2.3 | 1.6 |
References
G. LeBlanc, M. J. Boland, and Y. E. Tan, “The Australian Synchrotron Project Storage Ring and Injection System Overview”, in Proc. 9th European Particle Accelerator Conf. (EPAC'04), Lucerne, Switzerland, Jul. 2004, paper THPKF005
S. V. Weber et al., “Final Commissioning Results from the Injection System for the Australian Synchrotron Project”, in Proc. 22nd Particle Accelerator Conf. (PAC'07), Albuquerque, NM, USA, Jun. 2007, paper TUPMN007, pp. 926-928.