The lands of the aul are located on the territory of the rural settlement of Elbrus (municipal entity), which is part of the Elbrus region of Kabardino-Balkaria. The closest settlements to Neutrino are: Elbrus, Verkhniy Baksan, Kurmu, Kyzgen, Dzhapyr-Tala.
Toponymy
The sound of the name of the village is more reminiscent of the name of some famous fashion brand or enterprise associated with innovative technologies. The toponym was given to the village in honor of the fastest solar particle, which is being studied by scientists at the Baksan Neutrino Observatory, located in the local area.
Features of relief and climate
Neutrino is located in the Baksan Gorge at an altitude of about 1.6 km above sea level. The mountainous terrain and sudden changes in altitude had a significant impact on the local climate, which is characterized by the presence of hot foehn winds in the spring. The danger of such winds is that they are usually accompanied by a sharp drop in pressure, which has a bad effect on well-being.
Founding history
The village of Neutrino arose on the remains of the ancient settlement of Gubasanta, which occupied the territory of the right bank of the Guba-Santa-Suu River. The ancient aul was a settlement consisting of two quarters, in which representatives of two teips lived: the Tilovs and the Kurdanovs.
At the end of the Second World War, the entire population of Gubasanta was deported to Central Asia, and the lands were transferred to the Georgian SSR. In 1957, residents settlement were rehabilitated, but they had nowhere to return - no stone was left unturned from their homes.
In 1977, it was decided to create the largest scientific center in the Baksan Gorge, around which a new village was formed with the new name Neutrino.
Modern life of the village
All infrastructure and economic life Neutrinos are equipped to meet the needs of the Baksan Neutrino Laboratory.
IN modern world this scientific complex is the largest center that deals with experimental research in the field of astrophysics and nuclear physics. The observatory consists of underground laboratories divided into two tunnels more than 3.6 km long under Mount Andyrchi.
The main composition of the population is represented by Balkars (67%) and Russians (15%). Most of the employees of the laboratories of the Baksan research complex live in Neutrino.
Not far from the village (approximately 10-20 km) there are popular ski resorts - Elbrus and Cheget. Neutrino is an ideal place for a temporary refuge for ski tourists. Since the village is a little distant from the resort area, rental prices here are quite reasonable, and the road to the base will not take more than half an hour.
aslan wrote in February 9th, 2017An underground laboratory, radioactive carbon, the search for dark matter, supernova explosions... No, this is not a science fiction thriller. This is the Baksan Observatory.
Scientists have been hunting for neutrinos for a long time. Born in the depths of the Sun, these particles make it possible to understand what is happening inside our star. And those ejected by a burst of supernovae tell stories about deep space.
Neutrinos emitted from the Earth's interior have low energy and have not yet been caught, but in the future they will certainly provide information about our planet. It may be possible to use neutrinos for communication over long distances, deep under water and underground - after all, they move almost at the speed of light, have no charge and fly through everything that gets in their way without interacting with matter. Almost without interacting, sometimes they still collide with atoms, which is what they use at the Baksan Neutrino Observatory in Kabardino-Balkaria, one of the most important points on the map for world science. Here, deep underground, two neutrino telescopes operate at once.
3500 meters deep into the earth
Those who have been to the foot of Elbrus from the south probably paid attention to the sign with the name of the settlement “Neutrino” shortly before Terskol. In a series of ethnic names of settlements, the scientific word looks unusual. However, you won’t be able to see anything strange from the highway. The road here goes to the scientific building, and a little further on the hill there are several high-rise buildings where scientists, engineers and technical staff live. And the most interesting thing, the “heart of Neutrino,” is located on the other side of the gorge, across the Baksan River - the structures were built right under the mountain. This arrangement makes it possible to significantly reduce background radiation, which can affect the results of experiments.
A suspension bridge spans the turbulent stream. On one side of it hangs a sign “Avalanche Dangerous Zone”. Our travel companion, physicist, senior researcher at the Institute nuclear research RAS Valery Gorbachev says that in 2003 there was an avalanche here. It destroyed a technical building, literally razed it to the ground, and demolished a stop near the road. Snow crumbs then covered the windows of residential buildings on the other side of the slope.
But in the mid-90s, the object was already damaged by human hands. At night, unknown people seized an electric locomotive, which they use to move through kilometer-long tunnels, and carried out a pogrom in the laboratories. Since then, the entrance to the mountain was guarded, and all premises were locked.
There are already people standing at the entrance to the adit, as they themselves say, “waiting for the metro.” Soon the train arrives, although the residents major cities They are unlikely to recognize it as the carriages familiar to the metro. An electric locomotive, more like a rectangle placed on rails with two asymmetrically located headlights, pulls along a narrow-gauge track. railway trolleys. The transport operation is ensured by a whole staff of railway workers, and the train runs strictly on schedule. Did not have time? You will have to walk several kilometers in complete darkness.
You can take a nap along the way, it’s about 20 minutes inland to your destination mountain range. The train stops several times: sometimes someone goes out to his laboratory, and sometimes you need to open another gate - only to close it again right after the train. Finally we are there. The mark is 3500 meters. This is the final stop for most passengers. The train goes even further.
How to see neutrinos?
In the spacious room there is a change house where all employees are required to change their shoes. We are not ready for this, and they give us shoe covers. The attendant checks passes and issues keys. And so we pass through the high gate with the inscription “Gallium-Germanium Neutrino Telescope”. Abbreviated as GGNT.
“Wet cleaning is carried out here every day, and replacement shoes are needed so as not to carry dust and dirt from the mine,” says Valery, as we walk through the spacious rooms of the telescope. “All objects on the surface, and the rock inside the mountain contain radioactive isotopes.” They may affect the results of experiments. Therefore, the walls of the telescope are made of special concrete with a low content of radioactive elements and covered with metal sheets. Such protection reduces background radiation by tens of millions of times.
When the telescope is located under a mountain, there is no need to talk about a classic telescope with mirrors and lenses. There is no trace of any of this here. The “heart” of the GGNT consists of 50 tons of gallium, a light metal with a melting point of 30 degrees. It is placed in reactors, where it interacts with neutrinos - an elementary particle that has no charge and which practically does not interact with matter.
Neutrinos are born in the depths of the Sun in the process thermonuclear reactions and are immediately carried off into space. Some of them reach the Earth, but due to their properties, they fly through the planet and almost do not interact with it. Only a tiny fraction can be caught.
There are several installations in the world for recording these elusive space wanderers. The technology using gallium is unique in its kind. According to Gorbachev, the GGNT detects low-energy neutrinos, which other detectors are not capable of.
But even if it is caught, it is impossible to see the neutrino. You can only record the consequences of their interaction with the substance. This is how the GGNT catches one of three types - electron neutrinos. They crash into a gallium nucleus and transform it into the isotope germanium-71, which is in the next cell of the periodic table. Once a month, germanium thus formed is extracted from a gallium target (that’s what experts call 50 tons of this element).
“On average, only about 30 atoms are formed per month. Can you imagine how much work it takes to extract them from a multi-ton mass? - says Valery. — To do this, we add 250 micrograms of germanium, but another, non-radioactive one. Then with the help chemical reactions we extract it, put it in a special counter, and it determines the number of radioactive atoms. By the way, during the extraction of germanium, engineers remain in the laboratory for a day - the test is not an easy one.
That is why there is an aquarium here, although due to the surrounding atmosphere at first it seems that experiments are being carried out on the fish.
We move to a room where the number of isotopes formed is counted. It is not possible to see the meter itself - it is hidden by lead blocks, which, by the way, are everywhere here. - This is pure, non-radioactive lead. It protects the counters from external radiation, which can affect the purity of the experiment,” explains Gorbachev. One of the employees joins us. His responsibilities include auditing existing radioactive elements. Valery takes out a metal container with a characteristic radiation symbol from the safe, opens it and boldly picks up the radiation sources. “Of course, you shouldn’t swallow them, but you can hold them in your hands,” he jokes.
Sterile Neutrinos: Catch them if you can
It turns out that registering solar neutrinos is a daily routine that GGNT employees have been performing for many years. But now they are preparing a new experiment that could bring Nobel Prize. — Science knows three types of neutrinos: electron, muon and tau neutrinos. And they can turn into each other when they travel long distances. There is also a hypothesis about the existence of a fourth type - a sterile neutrino, which does not interact with matter at all, says Gorbachev.
It is sterile neutrinos that they are going to look for here. The new installation will be a tank with a radioactive source into which 50 tons of gallium will be pumped. Isotopes will emit neutrinos, which, just like in the GGNT, will begin to convert gallium into germanium. And then - the usual procedure for counting newly formed atoms. In general, sterile neutrinos that do not interact with matter will be searched for... by their absence.
When scientists expect to find a certain number of events and actually find fewer, it is reasonable to assume that the missing number of interactions are due to these elusive particles. Of course, you first need to get rid of all the side factors that can lead to the same results and cause confusion in the calculations.
For the new experiment, most of the necessary equipment is already available: a barrel and 50 tons of gallium. We still need to purchase a radioactive source, but there is no funding yet. — To launch the project we need 300 million rubles. This amount is not as large as it might seem, especially since we will receive scientific results five years after the launch of the project,” explains the physicist.
Underground sources and dark matter
There is less than an hour left before the electric locomotive departs, and we hurry further into the tunnel - to the mark of 3800 meters. We walk, and when we leave the entrance to the GGNT, we are enveloped in darkness. The sound of Narzan springs gushing out from under the ground can be heard. No one dares to drink this water, but the springs create bizarre stalactites and stalagmites. Laboratory staff chop them off and show them to guests.
Light appears ahead, and soon we approach the low-background research laboratory. There are no grandiose buildings here, so several experiments are carried out at once in a relatively small area. Almost all of them have practical purposes. Thus, a germanium low-background ultra-pure semiconductor detector helps to detect materials in which unstable isotopes are almost absent. Here they are looking for materials for other scientific experiments, explains Vladimir Kazalov, a researcher at the laboratory of the Institute of Nuclear Research.
— Many experiments require materials that contain very little thorium and uranium and their decay products. Here we select samples from those that are sent to us,” he says.
Carbon-14 is used to determine the age of archaeological and paleontological finds. Most of it is formed in the upper layers of the atmosphere; in small quantities it is found throughout the atmosphere. When an object falls underground, carbon-14 stops flowing into it. And since the isotope is radioactive, it decays over time.
Scientists count the remaining quantity and determine the age of the find - whether it is a dead prehistoric animal or a tool. ancient man. The detector has serious protection. The inside is copper and lead, and the top is covered with borated plastic.
In the next room, behind a 15-centimeter lead door, there is an installation for studying scintillators for the presence of carbon-14. Scintillators are substances that have the ability to emit light when absorbed ionizing radiation. They are also used to detect neutrinos. But carbon-14 is a radioactive isotope. According to Vladimir Kazalov, when an experiment requires a carbon-based scintillator, radioactivity only gets in the way. Therefore, the Laboratory of Low Background Research created an installation to search for scintillators with low carbon-14 content. Finding such a natural source is very difficult.
In the next room there is an installation for searching for hadronic axions - hypothetical candidate particles for dark matter. So far they have not been found.
— One day, a colleague of mine from Moscow, he is searching for dark matter, comes up to me and asks: “Have you discovered anything? Do not open. It’s still early,” jokes Kazalov.
By the way, while we move from one room to another, the temperature around us increases noticeably. Without artificial ventilation, the air here can warm up to 40 degrees and above: the radioactive elements contained in the rock release heat as a result of decay, and it accumulates here.
Old telescope for supernovae
An electric locomotive arrives. This time the journey takes less time, since we stopped about a kilometer from the surface. We are met by physicist Musabi Boliev. He leads us to the oldest building under the mountain - the Baksan Underground Scintillation Telescope (BPST), built in 1977. The telescope is a structure the height of a four-story building. It consists of tanks filled with kerosene in which a scintillator is dissolved. A photomultiplier tube (PMT) is inserted into each tank. There are 3186 of them in total. The inside of the tank is covered with white enamel, which reflects photons.
If low-energy electron neutrons are detected in the GGNT, then this telescope catches muons. They are formed when a muon neutrino crashes into an atom. These charged particles “pierce” the scintillator, resulting in the production of photons. Reflecting from the walls of the containers, they enter the photomultiplier; the signal from them is amplified many times and enters a computer system for analysis.
— At the time of construction, many did not believe that the installation would work. In each multiplier the voltage ranges from 1600 to 2000 volts. The signals from them need to be synchronized so that they all enter the equipment at the same time,” says Boliev.
The telescope is old, but it works flawlessly. PMTs, which were purchased in the 70s large quantities, are now in boxes along the wall. Most of them have not yet been needed. However, despite the fact that the telescope was built almost 40 years ago, today it solves fundamental problems in physics. In addition to statistical information about solar neutrinos, BPST registers catastrophic events in deep space, such as supernova explosions
It’s time to return, and Musabi Boliev undertakes to lead us back to the surface. This time we're going on foot. Everything, as in the well-known expression, is “the light at the end of the tunnel,” to which we were heading. Modern pop culture creates an aura of mystery around such objects: an underground laboratory, scientific research, radioactivity. The sound of dripping water in the dark and the whistle of a never-ending wind...
The reality turns out to be much more impressive. People here are not afraid of radiation because they know its nature and know how to handle it. There are no legends or fairy tales about the spirit of the mountain, because people work here scientific view. Being here, you feel involved in something great. Connection with space and, for that matter, with all progressive humanity interested in scientific problems.
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The first thing that attracted the children's attention was the snow, which, despite December, had not yet fallen. While they were deciding organizational matters with the leadership of the observatory, the children had a lot of snowball fights.
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We were surprised by the observatory's strict rules. Only persons over 12 years old can enter the observatory. Upon entering, we put on the shoe covers we had brought with us. Then we were invited to follow the senior researcher at the BNO, Rita Viktorovna Novoseltseva, who began her story about the observatory.
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The observatory's underground structures are located in two 3670 m long tunnels under Mount Andyrchi, their equivalent depth ranges from 100 to 4800 m of water equivalent. Belongs to the Institute of Nuclear Research of the Russian Academy of Sciences. She said that BNO has the following installations:
Baksan underground scintillation telescope (BPST) with a volume of 3000 m³ at a depth of 300 m below the surface;
gallium-germanium neutrino telescope (GGNT) - a radiochemical detector of solar neutrinos with a gallium metal target weighing 60 tons (SAGE project, located at a distance of 3.5 km from the entrance to the tunnel);
the Andyrchi installation for recording extensive air showers (EAS), located on the surface of a mountain (altitude 2060 m above sea level) above the BPST on an area of 5 × 104 m² and consists of 37 scintillation detectors;
complex of ground-based installations COVER (includes a Large muon detector, a scintillation telescope and a neutron monitor), designed to study the hard component of cosmic rays and extensive air showers).
The size of the structures and the tunnel were impressive.
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Zaynaf Uyanaeva asked what the observatory employees do? Our guide told us that they are studying the internal structure and evolution of the Sun, stars, the galactic core and other objects of the Universe by recording their neutrino radiation; search for new particles and ultra-rare processes predicted modern theories elementary particles, at a level of sensitivity inaccessible to other methods; research of high energy cosmic rays, gamma astronomy.
Valeria Nikoghosyan was interested in the question of the number of observatory employees and what specialists the BNO needs. We were told that the number of employees, including service personnel, is about 250 people, the majority live in the village of Neutrino. One of the employees of the BNO is a graduate of our school, a Soros Prize laureate - Sergei Kurenya. And to work at the observatory you need to graduate from the faculties of physics, mathematics, chemistry or radio engineering.
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The excursion was organized with the assistance of the uncle of the physics teacher of our school, candidate of physical sciences - Dakhir Daniyalovich Dzhappuev.
Towards the end at the 25th minute, reporters began to talk about a certain laboratory to which a 4-kilometer tunnel leads, in which the Baksan Neutrino Laboratory is located
As usual, the journalists lied. Here's what we managed to find about her:
“Construction began in 1967. The project involved the construction of two parallel horizontal tunnels in Mount Andyrchi (height more than 4000 m), along which it was planned to place physical installations. The underground location of the installations is due to the fact that the background from cosmic rays (muon flux) decreases along deepening underground and at the end of the tunnel almost 107 times lower than on the surface, the implementation of these plans was the creation of the Baksan Neutrino Observatory. A.A. Pomansky was appointed as the first head of the station. The location for the future observatory was chosen near Mount Elbrus. Baksan Gorge, located in the Kabardino-Balkarian Republic. Since 2003, an experiment has been carried out at the Carpet-2 installation to detect the hadronic component of EAS using a unique technique. As part of the experiment, during the analysis of experimental data, a new physical phenomenon was discovered that is at the junction. nuclear physics and geophysics - radon-neutron tidal waves. The Observatory's research program expanded as new above-ground and underground structures were put into operation. In the process of development, a complex of unique scientific structures arose at the BNO, meeting all modern requirements.
The creation of a complex of scientific installations made it possible: - to begin direct research into the internal structure and evolution of the Sun, stars, the galactic core and other objects of the Universe by recording their neutrino and gamma radiation;
- to search for new particles and ultra-rare processes predicted by modern theories of elementary particles at a level of sensitivity inaccessible to other methods;
In 1998 for the creation scientific complex BNO team of employees of the Institute and the Observatory was awarded the State Prize Russian Federation, in 2001, awarded for achievements in the field of research on the flux of neutrinos from the Sun International Prize them. B. M. Pontecorvo.
- to study the interactions of neutrinos and muons with matter in the region of high and ultra-high energies that lie beyond the capabilities of accelerator technology.
Main directions scientific research BNO are:
-particle physics, high energy physics, cosmology;
-neutrino astrophysics, neutrino and g-astronomy, cosmic ray physics, the problem of solar neutrinos;
-development and creation of neutrino telescopes in low-background underground laboratories for studying natural flows of neutrinos and other elementary particles;
-double beta decay;
Applied research includes:
-search for dark matter.
-checking the radiation purity of various natural and artificial materials, for example, raw materials for the production of scintillation single crystals;
-control of the natural environment;
Currently, the Observatory staff includes 29 researchers who are actively leading scientific work(2 doctors and 14 candidates of physical and mathematical sciences).
-study of the radioisotope composition of lunar soil delivered by the automatic stations “Luna-16” and “Luna-20”, etc.
The Observatory includes the following scientific units: -Baksan underground scintillation telescope;
- “CARPET” - installation for recording widespread atmospheric showers;
- "CARPET-2" is a complex installation for recording widespread atmospheric showers.
- "ANDYRCHI" - a mountain installation for recording widespread atmospheric showers;
- gallium-germanium neutrino telescope;
- low-background laboratory No. 1;
- low-background laboratory No. 2;
“Neutrino” is an ultra-light elementary particle that almost does not interact with matter. The fact that it exists was proven in the 50s of the 20th century. In the 60s, the Soviet government decided to build a special neutrino observatory in the Baksan Gorge. The location was not chosen by chance. In a “cocktail” of hundreds of types of other elementary particles, a neutrino is simply not visible: to detect it, you need a filter. The Andyrchi basalt mountain became just such a filter. Below it, at a depth of about 2 km, is a laboratory.
Getting to the place where neutrinos are caught is not easy. First you need to go to Nalchik, and from there it’s another 80 km, or to Mineralnye Vody, and then another 160 km. On the way, every now and then there are anti-terrorist police posts, and reliable security is posted at the entrance to the institute: once there was already an attempt to attack the laboratory.
The very last stage of the journey is a narrow adit, 4 km long, along which something like a cross between miner's trolleys and a children's train rides. The tunnels and premises in Mount Andyrchi were cut by detachments of metro workers from Baku and Minsk - hence the letter “M” at the entrance.
A 20-minute drive in almost complete darkness under layers of basalt - and the train stops in front of blind gates. They ensure the safety of laboratories.
Before entering the laboratory, everyone must change their clothes and shoes so that they do not bring isotopes of cosmic origin from the surface of the earth with dirt and dust on their shoes and clothes: they affect the background radiation. “It is suppressed here by 15-20 times compared to ordinary rooms due to special low-background concrete,” explains Alexander Shikhin, a researcher at the Baksan Neutrino Observatory. “The concrete here is about 70 cm-meter.”
Solar neutrinos are caught by an ultrasensitive gallium-germanium neutrino telescope. With its help, scientists are trying to understand what kind of processes occur on the Sun, how it shines and heats.
“Telescope is a very conventional name; in fact, it is a chemical detector,” says Shikhin.
Gallium is a light metal that melts right in your hands as soon as the temperature exceeds 30 degrees Celsius. It is he who interacts best with neutrinos. About 50 tons of gallium are stored in huge sealed Teflon barrels in the laboratory, with the help of which only a few dozen particles will probably be extracted.
“Through every square centimeter on the surface, even through my fingernail, every second about 70 billion neutrinos, which originated on the Sun, pass through. But the number of interacting ones can be one - in my entire life,” the scientist notes.
“In 1977-79, in my opinion, the first event was: a neutrino coming from below,” recalls Valery Kuzminov, head of the Baksan Neutrino Observatory. “It was a delight! Everything we were striving for!”
Chemist Olga Zhorova explains the technology of “searching” for particles:
With the help of complex chemical reactions, 50 tons of liquid metal are first converted into one and a half hundred liters of extract, then into two liters, and then into a glass of a clear solution. It is poured into a special glass installation, where the solution undergoes multi-stage purification from impurities using freezing in various traps, using liquid nitrogen, heating on titanium, iron, and carbon shavings. “And only then does it fall into various traps and end up in the highly clean vacuum part of the installation,” she lists.
The output is only half a cubic centimeter of germanium gas, which contains only 5-6 atoms left after the decay with traces of neutrinos. This material will be locked in a massive counter cube for many months to obtain fresh information from the very center of the Sun.
“This is a multilayer structure made of various low-background metals: a few cm of steel, 20 cm of lead, another 10 cm of copper, and there is still internal active protection inside,” Zhorova lists. “All this protects the meters from radioactivity, including the one we have we ourselves. And within this passive and active protection, within three months, the single decays of germanium-71, which was formed in the radiochemical detector during the exposure, are counted."
The largest room of the laboratory is the hall of the Large Scintillation Telescope, the size of a four-story building. It is lined from top to bottom with special particle detectors.
“There are approximately 3200 detectors, measuring 70 by 70 and 30. They are made of aluminum, coated inside with white enamel and filled with purified kerosene C9H20,” says Evgeny Martakov, engineer of the Large Underground Scintillation Telescope. According to him, scintillators are dissolved in kerosene - substances capable of converting particle energy into light. Special devices in black cylinders are photomultipliers. They read light signals and transmit them to recording computers. This is how scientists see the movement of particles in real time.
There is another telescope nearby, also the size of a house. It detects more powerful neutrinos, muons, which fly towards the Earth from deep space. Thanks to this telescope, almost 30 years ago, a supernova explosion was recorded in the Magellanic Cloud - more than 160 thousand light years from us.
“When a star explodes, we see it as if it were day!” – says Evgeny Martakov.
Another laboratory was opened later than the others, when Soviet Union has already broken up. Here they are looking for solar hadron axions, a particle whose existence theoretical physicists are still only guessing at.
Now, in the bowels of the laboratory, a facility is being installed for the BEST experiment, one of the most anticipated events in particle physics. With the help of this experiment, scientists are going to either prove or disprove the hypothesis of the existence of so-called “sterile” neutrinos, which have a significantly larger mass and even less interaction with matter. Perhaps this will help to understand nature dark matter and, perhaps, will bring scientists a Nobel Prize.
“If the result is negative, of course, we will not receive any prize, but it will be a good scientific result: it turns out that there is no such process, we don’t have to go there anymore,” says Valery Kuzminov, head of the Baksan Neutrino Observatory. “You won’t know, What do you have, is there a treasure there until you dig it up?”
The Baksan Observatory has long been of interest to fellow scientists from other fields of science: where else can you find rooms so cleared of radiation or such deep caves under the mountain? Biologists studied here the effect of radon gas on the body, and geophysicists asked to place their equipment in the very heart of the mountain. also in Soviet times American nuclear physicists from Los Alamos regularly visited the Baksan Gorge, conducted joint experiments, shared experience and knowledge. But today the intensity of cooperation has noticeably decreased.
The head of the laboratory complains that for the current Russian authorities basic science is also not a priority.
“Now the country, the state, the government is not ready to deal with such tasks, as I understand it. Priorities changed about a decade ago, when our international situation began to deteriorate sharply. Well, in general, capitalists do not need this, capitalists do not need fundamental science,” with Valery Kuzminov admits bitterly.
