The VEPP-3 electron-positron storage ring (original) (raw)
The VEPP-3 storage ring (perimeter: 74.4 m, injection energy: 350 MeV, maximal energy: 2000 MeV) was built in 1967-1971 and modernized in 1986-1987.
Main applications:
- booster for the VEPP-4M collider;
- synchrotron radiation production for users;
- X-ray lithography and LIGA-technologies;
- nuclear physics experiments using an internal gas target.
The experiments successfully finished:
- generation of coherent optic radiation by the VEPP-3 electron beam ("Optic clystron");
- gamma-quantum beam production by Compton back-scattering (ROKK-2 facility).
Electrons or positrons are injected from the "Positron" injector with 1 Hz rate. Maximal stored electron beam current is 500 mA, storage rate is 2-5 mA/min. Maximal electron beam current accelerated up to 2 GeV is 160 mA, acceleration time is about 4 min. Maximal stored positron beam current is 50 mA, storage rate is 0.04 mA/min.
The VEPP-3 layout in the PDF format is here.
Design lattice functions in the PDF format are here.
Main parameters
| Perimeter | 74.39 m |
|---|---|
| Revolution frequency | 4030.0 kHz |
| Beam energy injection extraction experiment | 0.35 GeV1.80 GeV2.00 GeV |
| Momentum compaction factor | 0.071 |
| Betatron tunes, horizontal/vertical | 5.10/5.20 |
| Damping factor, horizontal/vertical/longitudinal | 0.93/1.00/2.07 |
| Admittance, horizontal/vertical | 138/26 mm·mrad |
| Aperture in semi-rings | 55x24 mm2 |
| Accelerating RF system | 8 | 72 |
|---|---|---|
| Frequency | 8.06 MHz | 72.54 MHz |
| Harmonic number | 2 | 18 |
| Number of cavities | 1 | 1 |
| Maximal amplitude voltage per cavity | 20 kV | 800 kV |
| Maximal RF generator power | 20 kW | 150 kW |
| Cavity transit factor | 0.85 | |
| Design beam parameters | E = 350 MeV | E = 2000 MeV |
| Damping time of ver. betatron oscillation hor. betatron oscillation phase oscillation | 820 ms870 ms390 ms | 4.0 ms4.3 ms2.0 ms |
| Horizontal emittance | 0.009 mm·mrad | 0.292 mm·mrad |
| Beam size (betax=betay=5.5 m, D=1.2 m) hor. betatron hor. phase hor. total ver. (at 10% coupling) | 0.225 mm0.150 mm0.270 mm0.027 mm | 1.270 mm0.870 mm1.540 mm0.154 mm |
| Energy spread dE/E, r.m.s. | 0.0125 % | 0.072 % |
| Bunch length, r.m.s. | 23.5 cm | 9.1 cm |
| Energy loss per turn | 0.21 keV | 246 keV (with wiggler) |
| Synchronous phase | 174.9° | 150.4° |
| Synchrotron tune | 0.0004 (1.77 kHz) | 0.0066 (26.7 kHz) |
| Separatrix width phase dEsep/E dXsep (D=1.2m) | 4.1-308°0.59%6.33 mm | 30 -220°0.66%7.71 mm |
| Beam life time | 0.5-1.0 hour | 4-6 hour |