Sirius’ Storage Ring uses a 20-cell 5BA (Five Bend Acromat) magnetic lattice to achieve a very low beam emittance of 0.25 nm.rad, making Sirius one of the brightest synchrotron light sources in the world.
An innovation in the Sirius lattice is the introduction of high field permanent magnets of 3.3 T in the middle of the central 0.58 T dipole of the 5BA cell. Besides contributing to the reduction of emittance, these high field dipoles will also produce hard X-rays with critical photon energy of about 20 keV, producing usable photon flux up to about 120 keV.
The main elements of the magnetic lattice of the Sirius Storage Ring are 120 low-field dipoles (0.58 T), 20 high field thin dipoles (3.3 T), 260 quadrupole, 280 sextupoles, 160 slow horizontal orbit corrector magnets, 80 quick horizontal orbit corrector magnets, slow vertical 120 orbit corrector magnets and 80 quick vertical orbit corrector magnets.
| Parameters | Value | Unit |
|---|---|---|
| Energy | 3.0 | GeV |
| Gamma Factor | 5870.854 | – |
| Beta Factor | 0.999999985 | – |
| Velocity | $ 2.9979 \times 10^{8}$ | m/s |
| Magnetic Rigidity | 10.0069 | T.m |
| Nominal Current | 350.0 | mA |
| Parameters | Value | Unit |
|---|---|---|
| Type | 5BA | – |
| Circunference | 518.396 | m |
| Revolution period | 1.729 | µs |
| Revolution frequency | 0.5783 | MHz |
| Long Straight Sections | 5 x 7.5 | m |
| Short Straight Sections | 15 x 6.5 | m |
| Parameters | Value | Unit |
|---|---|---|
| Linear Momentum Compaction | $\rm 1.630 \times 10^{-4}$ | – |
| Transverse coupling | 1.0 | % |
| Betatron Tunes | 49.110 (h) x 14.165 (v) | – |
| Natural Chromaticities | -119.2 (h) x -79.1 (v) | – |
| Beam size at center of SS-A | 64.9 (h) x 3.4 (v) | µm |
| Beam size at center of SS-B | 19.1 (h) x 2.0 (v) | µm |
| Beam size at center of BC | 9.5 (h) x 3.5 (v) | µm |
| Beam divergence at center of SS-A | 3.8 (h) x 0.7 (v) | µrad |
| Beam divergence at center of SS-B | 13.0 (h) x 1.3 (v) | µrad |
| Beam divergence at center of BC | 26.9 (h) x 0.7 (v) | µrad |
| Parameters | Value | Unit |
|---|---|---|
| Natural Emittance | 0.251 | nm.rad |
| Natural Energy Spread | 0.085 | % |
| Natural bunch length | 2.5 (8.2) | mm (ps) |
| Energy loss from Dipoles per turn | 475.3 | keV |
| Energy loss from IDs per turn | 400.0 | keV |
| Radiation power from Dipoles | 237.6 | kW |
| Radiation power from IDs | 200.0 | kW |
| Damping partition number | 1.30 (h) x 1.00 (v) x 1.70 (L) | – |
| Damping time (dipoles only) | 16.78 (h) x 21.83 (v) x 12.83 (L) | ms |
| Parameters | Value | Unit |
|---|---|---|
| Frequency | 499.658 | MHz |
| Harmonic Number | 864 | – |
| Cavity Peak Voltage | 3.0 | MV |
| Synchronous phase | 163.0 | ° |
| Synchronous tune | $\rm 4.6 \times 10^{-3}$ | – |
| Synchronous frequency | 2.68 | kHz |
| Energy Acceptance | 5.1 | % |
| Parameters | Value | Unit |
|---|---|---|
| Magnetic Field | 0.5812 | T |
| Bending Radius | 17.218 | m |
| Critical Energy | 3.48 | keV |
| Number of Dipoles | 40 (B1) / 40 (B2) / 40 (BC_LF) | – |
| Hard-edge length of dipoles | 0.8280 (B1) / 1.2310 (B2) / 0.4250 (BC_LF) | m |
| Deflection angle | 2.76 (B1) / 4.10 (B2) / 1.58 (BC_LF) | ° |
| Parameters | Value | Unit |
|---|---|---|
| Magnetic peak field | 3.2 | T |
| Bending Radius at peak | 3.127 | m |
| Critical energy at peak | 19.15 | keV |
| Number of dipoles | 20 (BC_HF) | – |
| Deflection angle | 1.14 | ° |