The VEPP-2000 electron-positron collider: First experiments

In 2007, at the Institute of Nuclear Physics (Novosibirsk), the construction of the VEPP-2000 electron-positron collider was completed. The first electron beam was injected into the accelerator structure with turned-off solenoids of the final focus. This mode was used to tune all subsystems of the facility and to train the vacuum chamber using synchrotron radiation at electron currents of up to 150 mA. The VEPP-2000 structure with small beta functions and partially turned-on solenoids was used for the first testing of the “round beams” scheme at an energy of 508 MeV. Beam-beam effects were studied in strong-weak and strong-strong modes. Measurements of the beam sizes in both cases showed a dependence corresponding to model predictions for round colliding beams. Using a modernized SND (spherical neutral detector), the first energy calibration of the VEPP-2000 collider was performed by measuring the excitation curve of the phimeson resonance; the phi-meson mass is known with high accuracy from previous experiments at VEEP-2M. In October 2009, a KMD-3 (cryogenic magnetic detector) was installed at the VEPP-2000 facility, and the physics program with both the SND and LMD-3 particle detectors was started in the energy range of 1–1.9 GeV. This first experimental season was completed in summer 2010 with precision energy calibration by resonant depolarization.     

Recommissioning the Modernized VEPP-2000 Electron–Positron Collider

The VEPP-2000 electron–positron collider has been operating at the Budker Institute of Nuclear Physics (BINP) since 2010. Applying the concept of round colliding beams allowed the record value of the beam–beam parameter ξ ～ 0.12 to be reached. The upgrading of the VEPP-2000 complex, including the connection to the new BINP Injection Complex and modification of the electron–position booster and the BEP–VEPP-2000 transfer channels to work at 1 GeV, resulted in a significant increase in luminosity. Work on statistical data collection using detectors is in progress.     

High-performance ion-exchange chromatography of oligoribonucleotides using linear and hyperbolic salt gradients

A method for separation and chain length determination of oligo- and polynucleotides by high-performance anion-exchange chromatography was developed, which allows resolution of individual fragments according to their chain length n, up to n approximately 10 by linear gradient of sodium chloride and up to n approximately 30 by an hyperbolic gradient of this salt. The hyperbolic relationship between n and the salt concentration at which elution of the fragment occurs allows determination of the degree of polymerization of oligo- and polynucleotides with unknown n. The method proposed can be used for estimation of the effective charge of nucleic acids with complex structure.     

Status of Vepp-2000 BINP Electron–Positron Collider

Physics of Particles and Nuclei Letters - VEPP-2000 is the only electron–positron collider with round beams. This factor enables one to increase the beam–beam effect limit. During the...     

Commissioning of the Electron-Positron Collider VEPP-2000 after the Upgrade

The VEPP-2000 electron–positron collider has been operating at BINP since 2010. Applying the concept of round colliding beams allows us to reach the record value of the beam–beam parameter, ξ ~ 0.12. The VEPP-2000 upgrade, including the connection to the new BINP Injection Complex, the improvement of the BEP booster, and the BEP–VEPP-2000 transfer channels for operation at 1 GeV, substantially increases the installation luminosity. Data collection is in progress.