Institute for High Energy Physics

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Institute for High Energy Physics (IHEP) was opened in 1965 in Protvino near Moscow, Russia. The institute is known for the particle accelerator U70 synchrotron which was the largest in the world at the time it was launched in 1967.

In March 1958 the government of the USSR took the decision to create a new scientific centre for high-energy physics, which included the construction of an accelerator and experimental facilities. The design and geological search for a site were soon started, and after considering some 40 places, a site on the left bank of the Protva river 15 km from Serpukhov in Moscow Region, Russia, was chosen. The project concept was developed under the leadership of Vassily Vladimirsky, and in 1960 the construction of the 70 GeV proton synchrotron (U-70) began. At the time, it was the biggest proton accelerator under construction. On 15 November 1963 the Institute for High Energy Physics (IHEP) received separate institute status, with Anatoli Logunov appointed its director a month earlier. The creation of an efficient team of scientists and specialists from Dubna, Moscow and Kharkov became a decisive factor in pushing forward the construction of the machine, the experimental area and the infrastructure of the new centre.

1 Commissioning and first experiments
2 Continuing research programme
3 Particle accelerator accident
4 Disambiguation
5 References
6 External links

[edit] Commissioning and first experiments

The injector - a 100 MeV linac (L-100) - was put into operation in July 1967, and tuning the proton beam in U-70 began on 29 August. A circulating beam was achieved on 17 September and on 12 October a proton beam was accelerated up to the critical energy (8 GeV). However, on the night of 14 October, a record proton energy of 76 GeV was achieved in U-70.

One of the first experiments on the U-70 accelerator was the measurement of the yield of secondary particles produced by 70 GeV protons on internal targets. This work involved high-resolution gas-differential Cerenkov counters with very low background (~10^-6), and it allowed the study of pion, kaon and anti-proton yields up to momenta of 65 GeV/c. As a result, the new phenomenon of scale invariance was discovered in hadronic interactions at IHEP.

Immediately after the measurements of secondary particle yields, the IHEP scientific team began to study the energy dependence of total cross-sections in hadron interactions. The results of studies of total cross-sections in the energy range below 30 GeV confirmed the well known data obtained at the Brookhaven National Laboratory in the US and at CERN. However, at energies higher than 30 GeV, while the total cross-sections for π^+/-, K^- mesons and protons remained constant, cross-sections for K⁺ mesons began to rise. The rise of the total cross-sections for K⁺p interactions in the range 15-55 GeV/c was equal to a few per cent. A number of international conferences in high-energy physics focused on this new phenomenon and the discovery became known as the Serpukhov effect. The measurements of total cross-sections at higher energies at CERN and at Fermilab confirmed the results that the IHEP had obtained at U-70, and the rise in total cross-section was found to be a universal phenomenon for all hadrons.

Next, in 1970, came the discovery of antihelium nuclei composed of two antiprotons and one antineutron. The program of antimatter studies was completed in 1973 as, in a series of experiments, four antitritium nuclei, containing one antiproton and two antineutrons, were detected.

[edit] Continuing research programme

The joint research program at U-70 with physicists from JINR, CERN, the US and Japan has continued to the present day. The most well known physics results concern high spin mesons, glueballs and hybrids, while in detector and accelerator techniques important work has been done on polarization effects at high energies, GAMS-type spectrometers, liquid-argon spectrometers, lead-tungstate crystals for electromagnetic calorimetry and beam extraction by bent crystals. Of particular note are the invention of RFQ focusing and the construction of the first RFQ linac, URAL-30, at IHEP. ^[1]

After the commissioning of the larger accelerators at Fermilab and at CERN, the physicists at IHEP began to take an active part in the experiments at higher energies. These included the neutrino experiments with the 15 ft bubble chamber; polarization experiments and experiments with D0 atFermilab; experiments with GAMS-4000, EHS and BEBC at CERN's Super Proton Synchrotron; and experiments with DELPHI at LEP and with PHENIX at RHIC, Brookhaven.

Nowadays, physicists from IHEP, together with those from JINR, CERN, INR, ITEP, MSU, MEPhI, LPI, KEK and the University of Michigan, are continuing their research programmes at U-70 in the fields of meson spectroscopy, K-meson rare decays, polarization effects and neutrino interactions. A unique channel of separated K-mesons is under construction at IHEP, the basic elements of which are two superconducting deflectors received from CERN. Among the latest results that have been obtained at U-70 are high-precision measurements of charged kaon decays, spin asymmetries in inclusive reactions and new data on the search for exotic mesons.

Presently there are 5 members of the Russian Academy of Sciences, more than 270 scientists with Doctor degrees and Candidates of sciences.

[edit] Particle accelerator accident

In 1978, Anatoli Bugorski, a researcher working at IHEP was involved in an accident with a particle accelerator. A proton beam measuring about 200,000 rads entered his skull, but he survived.^[2]