The measurement results of carbon ion beam structure extracted by bent crystal from U-70 accelerator

The carbon ion +6C beam with energy 25 GeV/nucleon was extracted by bent crystal from the U-70 ring. The bent angle of silicon crystal was 85 mrad. About 2*105 particles for 109 circulated ions in the ring were observed in beam line 4a after bent crystal. Geometrical parameters, time structure and ion beam structure were measure

Application of optical methods in tests of new materials with gradient structure

The main idea of the article is to demonstrate the possibility of applying the laser dynamic speckle interferometry technique to control the processes of fatigue failure of specimens with a gradient structure. A distinctive feature of the described technique is the possibility of practical application on high-frequency machines as an experimental non-contact method for recording surface changes in the studying objects with a complex structure. Besides, the proposed technique can be used as an indicator characterizing irreversible processes during fatigue failure and for analyzing the fatigue crack growth kinetics. © Published under licence by IOP Publishing Ltd.Russian Foundation for Basic Research, RFBR: 18-38-00339_mol_aThe work was performed using the equipment of the collective use center «Plastometriya» with partial financial support from the RFBR grant №18-38-00339_mol_a regarding the study of the behavior of laminated materials under cyclic loading and state assignment topic №AAAA-A18-118020790148-1 regarding the creation of methods for detecting prefracture zones in metal composite materials and structural elements

Channeling and Volume Reflection Based Crystal Collimation of Tevatron Circulating Beam Halo (T-980)

The T980 crystal collimation experiment is underway at the Tevatron to determine if this technique could increase 980 GeV beam-halo collimation efficiency at high-energy hadron colliders such as the Tevatron and the LHC. T980 also studies various crystal types and parameters. The setup has been substantially enhanced during the Summer 2009 shutdown by installing a new O-shaped crystal in the horizontal goniometer, as well as adding a vertical goniometer with two alternating crystals (O-shaped and multi-strip) and additional beam diagnostics. First measurements with the new system are quite encouraging, with channeled and volume-reflected beams observed on the secondary collimators as predicted. Investigation of crystal collimation efficiencies with crystals in volume reflection and channeling modes are described in comparison with an amorphous primary collimator. Results on the system performance are presented for the end-of-store studies and for entire collider stores. The first investigation of colliding beam collimation simultaneously using crystals in both the vertical and horizontal plane has been made in the regime with horizontally channeled and vertically volume-reflected beams. Planning is underway for significant hardware improvements during the FY10 summer shutdown and for dedicated studies during the final year of Tevatron operation and also for a "post-collider beam physics running" period.Comment: 3 pp. 1st International Particle Accelerator Conference: IPAC'10, 23-28 May 2010: Kyoto, Japa