by Acad. Alexander SKRINSKY, director of the Budker Institute of Nuclear Physics, president of the Joint Scientific Council on Physicotechnical Sciences, Siberian Branch of the Russian Academy of Sciences (SB RAS)

Mathematics is commonly known as the queen of sciences. But this is just as true of physics, too - a science essential to the cognition of matter and the universe. A number of research institutes of the RAS Siberian Branch are closely involved with physics and related areas.

ON COLLIDING BEAM LINES AND MORE

Our Institute of Nuclear Physics (known as IAF) became the first physics research center set up east of the Urals in 1957 and named after Hersch Budker (1918 - 1977), its founding director. IAF was the first both in birth and in scope. Budker had turned to the job at hand well in advance, while still working at Moscow's famous Laboratory of Measuring Instruments affiliated with the Academy of Sciences of the USSR (this laboratory subsequently grew into the Russian Research Center "Kurchatov Institute"*). He would not wait for ground breaking in Novosibirsk, the designated location of his brainchild. Still in Moscow Budker selected the personnel, young people first and foremost, the IAF backbone. In a few years' time IAF got its buildings at Academgorodok in Novosibirsk and its staff pulled up stakes and landed in Siberia.

Moving to Novosibirsk, Budker incubated the idea of an accelerator on colliding electron-electron beam lines. This setup, the VEP-1 collider**, was commissioned in 1965. The first experiments made then and there actually concurred with those at Stanford University of the United States, opening up new avenues of research. Electron-positron colliding beams offered even better opportunities for physics of elementary particles. Such experiments were carried out by IAF on another collider, VEPP-2, in 1967, bringing the coveted Lenin Prizes to five IAF researchers. The IAF research center developed a family of electron-positron colliders. Today IAF is

* See: Ye. Velikhov, "He Dreamt of a Sun on Earth", Science in Russia, No. 1, 2003. - Ed.

** Collider - an accelerator in which two beams of charged particles (electrons, protons, positrons, antiprotons, etc.) move toward each other, interacting at the point of their encounter (collision). - Ed.

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closely cooperating with laboratories abroad, and is participating in the Large Hadron Collider (LHC) project, an accelerator with a perimeter of 28 km*, at CERN, the European Center for Nuclear Research, Switzerland.

We are proud that most of the results on elementary particles energized to 2 GeV and many others achieved in the range of up to 11 GeV (entered in international reference books) were obtained at our IAF. Our works on the high-precision measurements of the masses of elementary particles on colliding electron-positron beam lines by the method of resonance depolarization were awarded a USSR State Prize in 1989.

One striking idea of Budker's carried on with much success by his pupils is in the possibility of the electron cooling of beams of heavy particles (protons, antiprotons, multicharged ions) with the aim of increasing their density (this work merited an RF State Prize for 1997). Today our research collective is developing new electron cooling setups for world research centers.

Budker came up with a brilliant idea of a magnetic plug (mirror) trap for thermonuclear plasma confinement (containment). Subsequently his idea was materialized

* See: L. Smirnova, "Stepping into the Twenty-First Century", Science in Russia, No. 1, 1996. -Ed.

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in upgraded systems - multiplug, gasodynamic and ambipolar ones: born at IAF, they gained recognition worldwide.

Although the tokamak* toroidal system has been chosen as a prototype of the world's first experimental thermonuclear reactor, open magnetic traps must have their say. Thus, thermonuclear parameters we have demonstrated in recent years are close to those needed for sustaining a thermonuclear reaction. Powerful 14 MeV reactors could be developed on this basis for the thermonuclear materials science and for the burning up of spent nuclear fuel.

We should mention another remarkable result obtained by our theoreticians and experimentalists: they have predicted and experimentally detected the nonparity effect in atom transitions, and this is proof positive of the validity of the electroweak interaction theory.**

And last, about the applied aspect. Speaking about IAF achievements, one usually means basic research first and foremost. But spin-offs from this research are just as important. When charged particles are accelerated in a ring setup, they give rise to what physicists regard as a deleterious effect, and this is synchrotron radiation which carries away the energy pumped into a beam. But our researchers have succeeded in putting this phenomenon to good use by establishing the Soviet Union's first multiuser pool - quite a few nuclear physicists of this and other countries have worked at its stations. They are studying the atomic characteristics of solid bodies, chemical reactions, diamond formative processes in a Shockwave as well as biological processes. We are discussing the idea of setting up an up-to-date specialized synchrotron radiation source for the entire Siberian Branch of RAS (our experts have installed a similar facility at the Russian Research Center "Kurchatov Institute" in Moscow).

The commissioning of the world's most powerful source of terahertz (submillimeter) radiation, a laser on free electrons, in 2003 was the logical follow-up of this work. This laser setup is evolving into a basic part of the multiuser pool of photochemical research at SB. The initial results are impressive indeed. Thus, a biologist's dream has come true: it has become possible to effect soft ablation (separation from hard surface) of protein molecules without impairing their biological activity.***

And yet another thing. Our electron beam accelerators are now used in industry for a variety of purposes - from medical equipment sterilization to upgrading the electric properties of cable insulation. IAF has supplied over a hundred setups like that to customers in this country and abroad.

Using high-sensitivity sensors originally meant for elementary particle studies, we have developed X-ray units with a radiation dose down to hundredth fractions compared with conventional apparatuses and not higher than a dose received by air passengers in ten minutes of flight at altitude 10,000 m. Several air terminals of this country have installed our sensors for inspection and clearance purposes-they can spot any objects on a passenger's body, in pockets and even in the stomach (an important thing for detection of drug dealers).

FROM DISCOVERIES ON TO TECHNOLOGIES

The Tomsk-based Institute of Strong-Point Electronics (ISE) opened in 1977 is one of our leaders in physics of fast electrophysical processes. Research into vacuum and gas discharges and their plasma characteristics is among its perennial topics. Its cycle of basic investigations has given rise to certain new lines of research related in particular to the creation of a new class of nano- and microsecond pulse setups with capacity ranging from dozens of megawatts to dozens of terawatts. These facilities operate on the basis of high-voltage generators using different elements (electronic, ionic and X-ray diodes, active media of lasers, etc.) as loads. Such units are working at dozens of Russia's research centers and enterprises. The United States, Britain, France and China have contracted for their purchases.

Yet another significant aspect of ISE activities in the applied sphere: electron-ion-plasma technologies for modification of surface characteristics of materials and products. The works on explosive electron emission (1976) and effects of external ionizing radiation on the generation of high-pressure impulsive discharges in what we term oversurged discharge gaps (1989) have been acknowledged as discoveries. As a matter of fact, in the past two decades or so, Russia has turned into a world's leader in pulse energetics largely owing to spectacular successes scored by Tomsk scientists. And in some areas they are certainly a Number One.

The Institute of Physics of Semiconductors is another major research body of physicotechnical orientation within SB. Founded in 1964, it had been headed by Acad. Anatoly Rzhanov (1920 - 2000), its organizer and director, for twenty-eight years, and now bears his name. This center is researching in semiconductor microelectronics and quantum generators. It has made good progress in studies on electronic processes on the surface of semiconductors and at the semiconductor-dielectric interface, and in studying quantum effects in semiconductor two-dimensional (quantum films), unidimensional (quantum filaments) and zerodimensional (quantum points) low dimensionality systems of complex geometry. Accordingly, specimens of nanotransistors with single-electron transport of charge carriers have been developed as well as models of

* See: V. Glukhikh, "On the Brink of the Thermonuclear Era", Science in Russia, No. 3, 2003. -Ed.

** The electroweak interaction theory - a unified theory of weak and electromagnetic interactions of quarks and leptons effected via exchange of two pairs of particles: massless photons (electromagnetic interaction) and heavy intermediate vector bosons (weak interaction). This theory was advanced in the 1960s by physicists Sheldon Glashaw, Steven Weinberg (USA) and Abdus Salam (Pakistan), Nobel prizewinners (1979). - Ed.

*** See: V. Shumny, "Priorities of Biology", Science in Russia, No. 5, 2007. - Ed.

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infrared photoreceivers operating at room temperature. The Institute has also made good headway in basic research, namely in the photogalvanic effect theory, in the physics of strongly correlated solid state systems and other quantum phenomena; these pioneering works have gained recognition here in Russia and abroad.

The Semiconductor Physics Institute has semiconductor microphotoelectronics as another major area of research activities. It has created a new generation of large-format matrix photoreceiving modules in the IF range on the basis of epitaxial* cadmium-mercury-tellurium layers and heterostructures with quantum wells.** Such modules are employed in infrared (IR) imaging, or heat vision, in scientific research, medicine, metallurgy, ecology, construction and other areas. The medical IR heat-vision set Suite, much superior to analogs in heat sensitivity, is employed with much success for the diagnosis of onco and many other diseases. Another product is represented in a microscope designed on the basis of matrix structures of indium arsenide used for checking on the quality of integrated microcircuits and for other purposes. Next come heat and night vision systems designed for round-the-clock and all-weather surveillance, control and detection of objects.

However, the greatest accomplishment of this research collective is materialized in molecular beam epitaxy setups, when a semiconductor film is formed from molecular beams on substrates in superhigh vacuum. Its growth parameters are controlled by fast spectral ellipsometers and diffractometers of fast electrons developed at the Institute and sent to research centers of this and other countries. The technology of molecular beam epitaxy makes it possible to create specimens of low dimensionality quantum objects (nanotubes, nanoshells, nanowire of complex configuration, rings and many other items) meant for further studies and use of their physical characteristics. Besides, the research collective is designing active media for electromagnetic radiation control.

The purity of silicon is vital to the quality of semiconductor-based setups. That is why the Semiconductor Physics Institute has developed a technology for obtaining large-diameter silicon crystals characterized by superhigh parameters in the structure, specific resistance and lifetime of charge carriers. Thereby a new generation power electronic devices was born: controlled thyristors, bipolar transistors with insulated gates, among others. Such devices are a major contribution to the realization of a major interindustrial program, "Power Electronics of Siberia" launched in 2002.

The Institute's research collective is engaged in active work in the field of gas lasers and nonlinear processes implicated in the interaction of optical radiation with matter. Systems of laser separation of isotopes are being

* With reference to epitaxy, or directional (oriented) growth of one monocrystal on the surface of another (substrate). - Ed.

** Quantum well - a potential well in a semiconductor restricting the motion of elementary particles. Being trapped there, the particles heretofore moving freely in three-dimensional space, can now move only within a plane, essentially two-dimensional, field. - Ed.

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designed on this basis. Add to this semiconductor lasers, including emitters of solitary photons on the basis of semiconductor quantum nanostructures. It is attempted to use solitary photons in fiber-optics communication systems (quantum cryptography).

At this point it will be in place to mention the Institute of Automatics and Electrometry (Novosibirsk), playing a significant part in the activities of the RAS Siberian Branch. Founded in 1957, it took up methods of measuring electric and nonelectric values and their automation, including analog-to-digital conversion of signals and mathematical evaluation of the results thus obtained. In time the scope of this research expanded to fundamental problems of automation. New research trends have come into being, such as radiation-matter interaction, fiber-optics communication technologies predicated on novel physical principles, digital processing of images and signals, and so on.

The Institute has a record of spectacular achievements in this field: works on nonlinear laser spectroscopy, and on the effect of light-induced drift of gases (discovered in 1979), which makes it possible to measure diffusion coefficients for excited atoms and molecules, and isotope separation. A new line of research in physics - light-induced gas kinetics - has thus been born. The Automatics and Electrometry Institute has developed high-precision optical technologies as well as computer technologies for remote diagnostics and control of dynamic processes, along with virtual reality and multimedia technologies.

ATMOSPHERE OF THE EARTH AND DEEP SPACE

The year 1969 saw the opening of the Institute of Optics of the Atmosphere (IOA) in Tomsk. Up until 1997 its organizer and first director was Vladimir Zuev (1925 - 2003), a leading light in atmospheric optics; today IOA has been named after him. IOA divisions have expanded into the Institutes of Strong-Point Electronics, Physics of Strength and Materials Science, and Monitoring of Climatic and Ecological Systems; their first directors were Acads. Gennady Mesyats and Viktor Panin, and RAS corresponding member Mikhail Panin. Their work as Acad. Zuev's deputies in charge of scientific research has added to their know-how and expertise.

IOA research staffs have accomplished a remarkable lot in devising ways and means of remote sounding of the atmosphere for ecological and meteorological control purposes - methods providing information on the parameters of actually all impurities in the air. The Siberian lidar* station measures the total concentration and vertical distribution of ozone and nitrogen oxides to an altitude of 50 km. Sea- and space-based tracking stations (lidar "Balkan" at the "Mir" orbital station) have been commissioned along with a flying observatory for atmospheric pollution monitoring from Norilsk up in the Far North to the Altai mountain land down south.

Yet another major research center affiliated with the RAS Siberian Branch is the Kirensky Institute of Physics (IP or IF) concerned with basic research. Organized in 1956 on the initiative of Acad. Leonid Kirensky (1909 - 1969)** and with active support from Mikhail Lavrentyev, at that time Academician-Secretary of the Physics and Mathematics Division, IF became integrated with the Siberian Branch of the USSR Academy of Sciences the following year, in

* Lidar - a meteorological laser locator in the IF range for a remote measuring of atmospheric characteristics. - Ed.

** See: N. Dobretsov, "First Regional Branch", Science in Russia, No. 4, 2007. - Ed.

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1957. Initially focused on magnetism exclusively, IF soon moved to interdisciplinary studies thanks to a breadth of vision on the part of its founder, Acad. Kirensky. Among other things, the Physics Institute took up biophysics that looked like an exotic field at the time. It was natural therefore that IF branched out into such independent centers as the Institutes of Biophysics, Chemistry and Chemical Technology, and the Institute of Computer Modeling, alongside the Special Design and Technology Office "Nauka" ("Science").

The IF collective is justly proud of outstanding results achieved in crystallophysics, physics of magnetic materials and photon crystals. A detailed crystallochemical analysis of perovskite (perofskite)* - like crystalline structures and a predicted possibility of synthesis on this basis of more than three hundred compounds are among its latest achievements. Now, perovskite-like substances include nonlinear-optical materials, high-temperature semiconductors as well as structures possessing ferroelectric, ferroelastic and many other practical characteristics. Some of these materials have already been synthesized in Krasnoyarsk. As to photon crystals, IF was one of the world's first to undertake their studies. Making rapid progress, this branch of science allows to create structures reacting to photons in much the same way as crystal structures do to electrons. The technologies of obtaining such crystals and controlling their characteristics have set the stage for a new generation of optical devices.

The Siberian Institute of Earth Magnetism, Ionosphere and Propagation of Radio Waves owes its birth to geophysical and astrophysical investigations launched in East Siberia late in the 19th and early in the 20th century. Set up in 1960 on the basis of the Irkutsk Magneto-ionospheric station, this research center was in 1992 reorganized into the Institute of Solar and Terrestrial Physics. Universal magneto-ionospheric stations were built in 1963 in the polar town of Norilsk and in the community of Podkamennaya Tunguska (Krasnoyarsk Territory). The following year, in 1964, regular observations of the sun were begun in field pavilions set up in the Eastern Sayan Mountains. Simultaneously, ground was broken for a solar optical laboratory over there, in the Sayans. The Baikal Astrophysical Laboratory was put up at Listvyanka, a community on the Lake Baikal shore, with a Large Solar Vacuum Telescope installed in it. Works on heliophysics** were stepped up with the coming

* Perovskite (perofskite) - a mineral of the subclass of complex oxides.

** See: V. Orayevsky, V. Kuznetsov, "The Sun, the Earth, and the Stars...", Science in Russia, No. 5, 2002. - Ed.

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of Vladimir Stepanov (corresponding member of the USSR Academy of Sciences as of 1968), an eminent student in solar physics, as director. In 1972 work began on a Large Siberian Radiotelescope commissioned in the 1980s. Since then a far-flung and in many respects unique network of observatories and tracking stations has been built all the way from the Russia-Mongolia border in the south to Norilsk, a town within the Arctic Circle up in the Far North. This is all the more important now because many similar objects were lost to Russia with the breakup of the Soviet Union.

The Institute went on building up its research potential in spite of the heavy odds of the hard perestroika years of the late 1980s and 1990s, when its mere survival was at stake. In the 1990s it created a high-power radar of incoherent radio waves scattering, the only one in Russia, for studying the earth's upper atmosphere; it has a high information potential. The data obtained with the use of this setup are of great significance for understanding the nature of physical processes going on in the upper ionosphere, their relationships with geophysical processes in the magnetosphere of the earth, and other things.

Lately new ionospheric digital complexes have been put into service. Stations employed for measuring the earth's magnetic field have been upgraded and integrated within the international network INTERMAGNET Also, an up-to-date system of experimental radio paths has been established; employing new apparatuses for ionosphere sounding, this system has brought results of big practical significance for exploring the structure of the polar ionosphere and propagation of radio waves at high latitudes.

In July of 2004 the Sayan solar observatory, joining hands with the LOMO enterprise of St. Petersburg, completed work on an IR telescope, the only one in Russia, with a diameter of 1.7 m across. It is employed for the exploration of cosmic sources of thermal radiation with temperatures in the 300 - 3,000 K range. This telescope is also used for determining the characteristics of asteroids and comets approaching the earth; for the observation of artificial celestial bodies and assessing their condition. With the aid of high-power experimental setups Irkutsk scientists are contributing to the world databases on physics of the sun and solar-terrestrial relations, thus incorporating the results of studies conducted over many years.

The Irkutsk Institute, apart from making a major contribution to fundamental studies, has done a good deal for boasting the country's economy and its defense capability. It has obtained data on the effects of the environment on the performance of radioelectronic equipment of space vehicles and on the causes of such effects; more than that, it has offered practical tips for neutralizing them. It has designed models of the iono- and magnetosphere which are of great practical significance for radio communications. A ramified network of ground-based stations and ranges deployed over a large area enables the diagnostics of the state of circumterrestrial space and the prediction of bad "space weather" bouts.

Way back in 1947, that is long before the setting up of the Siberian Branch of the USSR Academy of Sciences, Dr. Yuri Schafer organized a station in Irkutsk for studying cosmic rays. Together with his colleagues Dr. Schafer carried out works on the physics of cosmic rays. The Irkutsk station was subsequently reorganized into a laboratory and then, an observatory. Finally, in 1962, it formed a groundwork for a research center in its own right, the Institute of Cosmophysical Studies and Aeronomy (IKFIA) under the umbrella of the SB of the

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USSR Academy of Sciences; in 2002 it was named after its founder, Dr. Schafer.

This Institute has quite a few achievements to its credit. But one is really a world class discovery, and this is an equation describing the transfer of cosmic rays, a basis for the present theory of their propagation.

The Yakutsk setup of broad air showers that IKFIA commissioned in 1973 is designed for studying ultrahigh energy rays. These are beams of particles whose energy (over 10¹⁷ eV) is many orders of magnitude superior to energies at accelerators. The very term, a "broad air shower", reflects the fact that cosmic particles brought in from outer space trigger a shower of sundry secondary particles (electrons, positrons, mesons, muons, etc.). The substance of the IKFIA-devised method boils down to registering such articles by means of correlated ground-based detectors. The relatively low intensity of cosmic rays at superhigh energies makes it necessary to monitor a very large territory - the area of the Yakutsk detector setup makes up 10 km². In 1982 IKFIA researchers (who worked in a joint group of scientists from several research institutes) merited a Lenin prize for the designing of this setup and the results obtained with its aid.

Space studies carried on by IKFIA over more than fifty years have culminated in a breakthrough on a foremost problem of astrophysics, namely the origin of cosmic rays. A hitherto unknown phenomenon, that of effective generation (acceleration) of cosmic rays on the fronts of Shockwaves, was discovered. A theory of this phenomenon postulates that bursts of supernovae are the principal source of cosmic rays in the galaxy. Even though more experiments are needed for exhaustive answers to these sticky problems, the importance of this IKFIA achievement can hardly be overestimated.

POSSIBILITIES OF LASER

The Novosibirsk Institute of Laser Physics (ILP/ILF) was set up officially in 1991. But its real history goes back to 1957 as a research collective of the Institute of Radiophysics and Electronics of the SB of the USSR Academy of Sciences formed its core. Owing to fundamental studies in the field of resonance nonlinear interaction of laser radiation with atomic gas - these studies were carried out by Veniamin Chebotayev (1938 - 1992; elected to the Russian Academy of Sciences in 1992) and coworkers-and his method of saturated absorption, it became possible to up the resolving power of spectroscopy in the optical range 40 to 50 fold. A new line of research thus came into being - superhigh-resolution laser spectroscopy.

Works on ultrastable frequency lasers opened up essentially new opportunities for progress in basic physics and were instrumental in boosting (by 3 to 4 orders) the precision of frequency and coordinate-time measurements. ILF has detected and studied physical phenomena in optics, something that expands our knowledge of the atomic and molecular structure of matter and provides precise data on the constants of quantum transitions and interaction of atoms. The first ever femtosecond optical clock has been developed, with its time and frequency scale involving the use of high-stability ultrashort optical pulses. This achievement has revolutionized the field of high-precision optical measurements. As demonstrated, it is possible to improve the accuracy of absolute frequency measurements to 10^-17 -10^-18 from the radio to the ultraviolet frequency band. Furthermore, it is possible to realize a variety of optimal experiments in the high-precision spectroscopy of hydrogen, deuterium, muonium and other atoms, in upgrading the accuracy of physical constants, in verification of quantum electrodynamics, and in creating a uniform standard of time, frequency and length.

ILP-developed techniques, principles and hardware are being widely used by leading research and metrological centers of the world. There is every ground to believe that ILP will achieve a breakthrough in high-precision measurements and optimize them dozens of times over compared with what we are having at present.

ILP laser technologies expand the range of laser users in many fields including medicine, ecology and other areas. ILP has built an ophthalmological unit for microsurgery of the cornea of the eye. It has designed and manufactured a surgical scalpel and a stomatological apparatus - all that for medics. Geologists and civil engineers can make use of ILP-made facilities like an automatic meter for spotting minor dislocations and deformations of the earth crust over long distances, for prediction of earthquakes and for control of surface man-built structures and dams. A universal technological complex for metal smelting, cutting and surface hardening involves a high-power CO₂ laser. ILF has conceptualized laser-based plasma technologies for synthesis of nanocomposites.

Physicists of the RAS Siberian Branch have won many prestige prizes at home and abroad. They are optimistic about the future. Our scientists will continue to combine basic research in fundamental properties of matter with efforts in creating research tools for other scientific disciplines.

Illustrations supplied by the author