18 research outputs found
Studies and application of bent crystals for beam steering at 70-GeV IHEP accelerator
This report overviews studies accomplished in the U70 proton synchrotron of
IHEP-Protvino during the recent two decades. Major attention is paid to a
routine application of bent crystals for beam extraction from the machine. It
has been confirmed experimentally that efficiency of beam extraction with a
crystal deflector of around 85% is well feasible for a proton beam with
intensity up to 1012 protons per cycle. Another trend is to use bent crystals
for halo collimation in a high energy collider. New promising options emerge
for, say, LHC and ILC based on the "volume reflection" effect, which has been
discovered recently in machine study runs at U70 of IHEP (50 GeV) and SPS of
CERN (400 GeV).Comment: 12 pages, 14 figure
Crystal collimation experiment on 70-GeV proton accelerator
The first proof-of-principle experiment on "crystal collimation" was performed with 70-GeV protons on IHEP accelerator. A bent crystal installed in the ring as a primary element upstream of a collimator has reduced the radiation levels downstream in the accelerator by a factor of two. The measurements agree with Monte Carlo predictions
Adatoms in Graphene
We review the problem of adatoms in graphene under two complementary points
of view, scattering theory and strong correlations. We show that in both cases
impurity atoms on the graphene surface present effects that are absent in the
physics of impurities in ordinary metals. We discuss how to observe these
unusual effects with standard experimental probes such as scanning tunneling
microscopes, and spin susceptibility.Comment: For the Proceedings of the "Graphene Week 2008" at the ICTP in
Trieste, Italy. 8 pages, 8 figure
Proton Extraction from IHEP Accelerator Using Bent Crystals
IHEP Protvino has pioneered the wide practical use of bent crystals as
optical elements in high-energy beams for beam extraction and deflection on
permanent basis since 1989. In the course of IHEP experiments, crystal
channeling has been developed into efficient instrument for particle steering
at accelerators, working in predictable, reliable manner with beams of very
high intensity over years. Crystal systems extract 70 GeV protons from IHEP
main ring with efficiency of 85% at intensity of 1.E12, basing on multi-pass
mechanism of channeling proposed theoretically and realised experimentally at
IHEP. Today, six locations on the IHEP 70-GeV main ring of the accelerator
facility are equipped by crystal extraction systems, serving mostly for routine
applications rather than for research and allowing a simultaneous run of
several particle physics experiments, thus significantly enriching the IHEP
physics program. The long successful history of large-scale crystal
exploitation at IHEP should help to incorporate channeling crystals into
accelerator systems worldwide in order to create unique systems for beam
delivery. We report recent results from the research and exploitation of
crystal extraction systems at IHEP.Comment: Invited talk at the International workshop "Relativistic Channeling
and Related Coherent Phenomena", Frascati (Rome) 23-26 March 200
THE EFFECT OF SYSTEMICALLY-ADMINISTERED RENOKINASE ON VOLUMETRIC CORONARY VENOUS FLOW-RATE IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION
THE EFFECT OF SYSTEMICALLY-ADMINISTERED RENOKINASE ON VOLUMETRIC CORONARY VENOUS FLOW-RATE IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION
Improving the design of horizontal continuous casting machines
15.00; Translated from Russian (Stal' 1986 (9) p. 31-32)SIGLEAvailable from British Library Document Supply Centre- DSC:9022.06(BISI--25538)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo
First Results of Investigation of Radiation from Positrons in a Crystalline Undulator
The sensing properties of titanium oxide have been tailored through doping with niobium and dispersion of nanosized Au particles. The microstructural features of the gold-titania composite system were investigated by transmission electron microscopy and the electronic properties of Au nanoparticles were specifically investigated by electron holography. Holography provides quantitative determination of the mean inner potential with the high spatial resolution attained by transmission electron microscopy. Large increase of the mean inner potential has been measured for ultra small Au particles arising from the nano-scale assembling. Electrical tests were performed at low operating temperatures and demonstrated the considerable enhancement of CO sensitivity owing to the extremely high catalytic activity of gold particles