Element hunter Yuri Oganessian on creating new chemical elements (20-03-2016)

Russian nuclear physicist Yuri Oganessian from the world renowned nuclear lab in Russia's Dubna welcomes the first non-Russian film crew at his lab, talking on how to find new chemical elements.

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00:00:01 Could you tell me what is so unique of this institute?
00:00:07 This is the Joint Institute for Nuclear Research, the JINR.
00:00:12 It celebrates its 60th anniversary this year.
00:00:18 Accidentally...
00:00:22 ...I came to work for the institute the year it was established.
00:00:27 And I've been working here ever since.
00:00:33 Its mission is...
00:00:35 ...to research fundamental issues in nuclear physics...
00:00:41 ...in high energy physics...
00:00:44 ...or particle physics as we call it...
00:00:46 ...and in condensed matter physics.
00:00:49 We do research in theoretical physics...
00:00:52 ...which is applicable to every area I mentioned.
00:00:56 We have got departments of mathematical studies and IT...
00:00:59 ...and everything else scientists would need nowadays.
00:01:08 JINR is an experimental facility.
00:01:10 We have got powerful research tools...
00:01:14 ...including smaller, bigger and super powerful particle accelerators...
00:01:19 ...a nuclear reactor...
00:01:21 ...and a lot of other instruments.
00:01:28 18 countries...
00:01:31 ...are...
00:01:34 ...JINR Member States.
00:01:36 The Institute receives funding from its Member States.
00:01:41 The JINR highest governing body is the Committee of Plenipotentiaries...
00:01:46 ...who are appointed by Prime Ministers of the Member States.
00:01:54 The JINR Scientific Council defines the science policy of the institute.
00:02:00 The Scientific Council meets twice a year.
00:02:03 The members of the Council are prominent physicists...
00:02:10 ...in all the areas that I mentioned earlier.
00:02:14 They don't have to work for JINR. They are experts.
00:02:20 In between the meetings of the Scientific Council...
00:02:24 we work in Advisory Committees for Nuclear Physics...
00:02:27 ...Particle Physics and Condensed Matter Physics.
00:02:31 This is basically the way JINR operates.
00:02:35 Which countries are we talking about?
00:02:41 These 18 countries. Can you give some examples?
00:02:45 Yes, these countries are JINR Member States.
00:02:50 There are also some countries which are JINR Associated Member States.
00:02:56 The Associated Member States are interested in specific areas of physics.
00:03:02 The JINR Member States include...
00:03:09 ...Czech Republic, Bulgaria...
00:03:12 ...Romania, Poland.
00:03:14 The East European countries.
00:03:16 Other JINR Member States include Vietnam...
00:03:21 ...Mongolia...
00:03:24 ...Cuba.
00:03:28 The Associated Member States are Germany, South Africa...
00:03:34 Italian physicists are very enthusiastic about this cooperation.
00:03:38 American physicists work in one of our Laboratories.
00:03:42 JINR is deeply rooted in the system of international cooperation.
00:03:49 I would like to mention...
00:03:52 ...that this system of international cooperation...
00:03:55 ...was established back in the Soviet era.
00:03:59 Back then the international cooperation was not very active.
00:04:03 Despite that fact, JINR was granted this advantage.
00:04:08 We ran ahead of many other institutions.
00:04:13 And even nowadays the legacy of those times...
00:04:17 ...lives on and we build on it in our work.
00:04:20 This is why...
00:04:22 ...I mean...
00:04:23 ...JINR is well-known for its accomplishments...
00:04:27 ...as well as for its deep integration into the world science.
00:04:31 Numerous teams of our scientists work in CERN...
00:04:36 ...in the US Brookhaven National Laboratory...
00:04:42 ...in Fermilab and other research centers.
00:04:45 Foreign physicists come to JINR to use our particle accelerators.
00:04:52 This is a true spirit...
00:04:55 ...of science, which should be international.
00:05:04 And what is your role in it?
00:05:07 What is your role in the Institute?
00:05:10 What is your function?
00:05:12 We focus on three main areas of research:
00:05:17 particle or high energy physics, nuclear physics...
00:05:21 ...and condensed matter physics.
00:05:28 I am mostly involved in the nuclear physics research.
00:05:36 We use a wide range of accelerators in our programs.
00:05:41 We run a nuclear reactor...
00:05:43 ...and an accelerator of heavy ions in the neighboring laboratory.
00:05:48 Historically, physicists use accelerators of heavy ions...
00:05:52 ...for their research in nuclear physics.
00:05:55 I work in the Laboratory of Nuclear Reactions.
00:06:01 Essentially, we study the physics of heavy ions.
00:06:05 It became a separate area of physics soon after I came to work for JINR.
00:06:10 Back then, there were just two labs in the world working in this field.
00:06:14 One of them was located here.
00:06:17 The other one was in Berkeley, California.
00:06:21 But when it became obvious...
00:06:26 ...that we obtain so much scientific data in this area of physics...
00:06:32 ...many countries established new laboratories.
00:06:38 Including the USA, France, Germany, Poland.
00:06:46 There was one in Groningen, too. To name a few. And then...
00:06:51 ...National Laboratories of Heavy Ions were established.
00:06:56 Later we saw International Laboratories which run large colliders.
00:07:01 The CERN large collider accelerates both protons and heavy ions.
00:07:08 We are going to build a large heavy ion collider, too.
00:07:12 This is the area of research...
00:07:17 ...where we use...
00:07:19 ...very heavy particles to bombard the targets.
00:07:25 This area of physics is gradually developing.
00:07:29 There are large colliders in the USA, Japan and China.
00:07:37 Nowadays, nuclear physicists widely use...
00:07:42 ...this method to research the atomic nuclei.
00:07:46 This is something we do here, too.
00:07:50 Of course, this is a very complex subject.
00:07:53 We have to research the ways particles interact at various energy levels...
00:08:01 ...and the new particles and new nuclei they generate in this interaction.
00:08:10 And what is so different about these new nuclei?
00:08:19 One of our missions...
00:08:23 ...is to produce the heaviest nuclei...
00:08:28 ...which don't exist in nature.
00:08:33 We want to advance as much as possible.
00:08:37 We want to know the maximum possible atomic mass.
00:08:44 What is the limit?
00:08:47 What is the heaviest possible atomic nucleus?
00:08:50 It is interesting...
00:08:54 ...because if we want to answer this question...
00:08:58 ...we must build on everything we already know about the atomic nucleus.
00:09:03 Any uncertainty in our knowledge may generate multiple answers.
00:09:09 One of them would be correct. And the rest should be discarded.
00:09:15 Which in turn would oblige us to review earlier theoretical models.
00:09:20 This is sort of a sharp point which we can use...
00:09:23 ...to test out theories and our knowledge...
00:09:28 ...of atomic nuclei, nuclear forces, and nuclear transmutations.
00:09:34 For quite a while now...
00:09:39 ...physicists take great interest in this thing.
00:09:43 We want to answer this question.
00:09:45 I believe we wanted that even before the era of nuclear physics.
00:09:49 The man always eagerly probed for the limits of the material world.
00:09:57 Each time he interpreted his discoveries...
00:10:00 ...depending on his perception of the world around him.
00:10:05 Probably, the first deep analysis of the material world...
00:10:11 ...was performed at the end of the 19th and at the beginning of the 20th century.
00:10:17 Dmitri Mendeleev was the first person...
00:10:22 ...to put the elements you can find in soil in a certain order.
00:10:30 He created his periodic table of elements.
00:10:33 The chemical properties of elements can be put in a certain order.
00:10:39 The inner structure of the elements...
00:10:43 ...which we didn't know about back then revealed itself in a certain way.
00:10:49 Then we went further and developed the quantum mechanics.
00:10:55 Einstein, Rutherford, a model of an atomic nucleus.
00:10:58 The physics gained a momentum and started to develop really fast.
00:11:02 And it made us even more eager to go to the limit.
00:11:08 That was the golden age of physics when one discovery followed the other.
00:11:15 Every discovery transformed our perception of the world. And every time...
00:11:20 ...this new perception could have been tested...
00:11:26 ...on the nuclei in their excited state.
00:11:31 But we had to excite the nuclei which was always hard.
00:11:37 We don't get excited that easily either. The same thing here.
00:11:46 This is why we established the laboratory...
00:11:52 ...to research the ultimate limit of the nuclear mass.
00:11:58 We didn't do it from scratch.
00:12:01 It all started during World War II...
00:12:07 ...when the US scientists produced plutonium. It is a man-made element.
00:12:13 It was synthesized back in 1940.
00:12:19 By Glenn Seaborg and Philip Abelson.
00:12:22 The US built a nuclear reactor in 1943.
00:12:26 And it produced considerable amounts of plutonium.
00:12:32 We know that that plutonium was used to make a nuclear bomb.
00:12:36 We should also keep in mind that later the energy of plutonium was used...
00:12:40 ...for civilian purposes, too.
00:12:43 We used it to generate electricity and for many other things.
00:12:52 The atomic number of plutonium is 94.
00:12:57 The last naturally occurring element is uranium. Its number is 92.
00:13:01 They are just two digits away from each other.
00:13:06 But these two steps are the steps into the realm...
00:13:09 ...of elements which don't occur in nature and which we can only synthesize.
00:13:17 I wanted to draw your attention to the fact...
00:13:20 ...that these are also two steps into the past.
00:13:23 Because 4.5 billion years ago...
00:13:27 ...when the Earth was formed, plutonium was there.
00:13:30 Its half-life is 25.000 years. This is why it decayed before we could trace it.
00:13:37 But in the 20th century...
00:13:41 ...we found a way to produce it in the lab and explore its properties.
00:13:45 We developed a plutonium industry.
00:13:48 We breed hundreds of tons of plutonium.
00:13:56 We found the ways to put this element to use.
00:13:59 And we took just 2 steps. But why not take 3 or 4 or 5 steps?
00:14:05 And we started to do so.
00:14:08 6, 7, 8, 9, 10 steps.
00:14:14 Yeah, we continue.
00:14:17 Element 93. Could you start there?
00:14:21 Yes, this is...
00:14:26 Well...
00:14:28 We took 2 steps to produce plutonium with the atomic number 94.
00:14:33 Then we took 3, 4, 5, and 6 steps.
00:14:38 And finally, we approached the element...
00:14:43 ...which could not exist, theoretically.
00:14:49 But it does exist.
00:14:51 We went further and produced the next one. And the next one.
00:14:56 That meant there was something wrong with the classical theory.
00:15:01 It gave us an incorrect prediction of the limit.
00:15:05 The classical theory rules out...
00:15:09 ...elements with atomic numbers over 100.
00:15:13 But we produced elements with atomic numbers 102...
00:15:17 ...103, and 104.
00:15:21 Back in 1964.
00:15:25 That was not that long ago.
00:15:30 We knew that we had to find some explanation...
00:15:34 ...of this fact and many others...
00:15:37 ...which didn't fit in the old classical theory.
00:15:44 The old theory proved very useful.
00:15:47 It helped us explain a lot of things.
00:15:49 But it could not predict the limit. The predicted limit was incorrect.
00:15:54 And so, we had to develop a new theory...
00:15:58 ...that would help us understand...
00:16:01 First of all, it had to be the same efficient in describing the world.
00:16:04 But also, it had to explain why we can go beyond the limits of the classical theory.
00:16:12 We found an explanation...
00:16:16 ...in 1969.
00:16:21 The new theory gave us an opportunity to produce new elements.
00:16:26 But their half-life would be shorter and shorter with every new element.
00:16:34 Although it also predicts that the elements...
00:16:37 ...with large atomic numbers may have longer half-life again.
00:16:40 I wonder if you could imagine an island on the half-life timeline.
00:16:45 That would be an island made of very heavy elements.
00:16:49 Super-heavy elements as we call them.
00:16:52 And they will exist significantly longer...
00:16:56 ...than their lighter precursors.
00:17:01 They are placed in the periodic table...
00:17:05 ...where no elements can exist in accordance with the old theory.
00:17:10 But the new theory gives us this opportunity.
00:17:13 Hopefully the new one is correct.
00:17:16 Because it can also be wrong.
00:17:19 These are postulated elements.
00:17:24 We should prove if they exist or not.
00:17:28 At some point we will have to say yes or no.
00:17:36 And we have to do much work to do so.
00:17:42 We have to try and synthesize these elements.
00:17:48 And I don't mean the element with the atomic number 94.
00:17:52 Or 104. Or even 114.
00:17:57 We also have to explore their properties.
00:18:01 So...
00:18:02 How do you do that? I mean, making an element?
00:18:05 Yes, and all the best physicists and experimentalists came together...
00:18:10 ...to try and solve this problem.
00:18:17 The first experiment was conducted in 1970. Just a year later.
00:18:24 In France.
00:18:27 I was invited to participate in it in the Joliot-Curie Institute.
00:18:30 I took part in this experiment and we got no results.
00:18:35 The physicists put in great efforts to discover these elements.
00:18:39 They used powerful reactors to search for super-heavy elements.
00:18:46 We tried to trace them in the nuclear explosions.
00:18:50 We looked for them in nature.
00:18:53 In cosmic rays.
00:18:55 In various chemical reactions.
00:18:58 In nuclear reactions, which involved heavy particles and neutrons.
00:19:04 Unfortunately, those experiments...
00:19:08 ...yielded no results.
00:19:14 We launched this program...
00:19:19 ...back in 1970.
00:19:25 And I should say...
00:19:28 ...that we hadn't achieved any results by 1990.
00:19:34 And no results by 1995.
00:19:37 And we conducted those experiments in the biggest research centers...
00:19:42 ...in the US, in Dubna, Russia and France.
00:19:49 That was quite a difficult moment.
00:19:56 What should we do? We...
00:20:00 We couldn't produce any new elements.
00:20:03 And we could neither prove nor rule out their existence.
00:20:07 Is the theory incorrect again?
00:20:11 What if these elements don't exist?
00:20:14 But then we would have to review the theory once again.
00:20:18 The old one didn't work. The new one didn't work either.
00:20:23 So, we need one which would explain our earlier results...
00:20:27 ...and postulate that these super-heavy elements can't exist.
00:20:31 That was difficult. Because there were too many things to explain.
00:20:37 The things we had done in the nuclear physics for years.
00:20:44 That was quite disappointing.
00:20:49 Or what if we just didn't know how to produce these elements?
00:20:54 What if our instruments were not powerful enough to produce them?
00:21:00 That moment I thought...
00:21:05 And my colleagues thought that too.
00:21:08 Most probably we didn't have tools to produce those elements.
00:21:15 Should we change our philosophy then? What if we set wrong objectives?
00:21:21 But then we synthesized some new elements before.
00:21:24 Those were not super-heavy ones. Probably that's where the difference lies.
00:21:30 We had to raise the bar significantly.
00:21:33 We decided to use artificial material to make our target.
00:21:39 That meant we had to use powerful reactors...
00:21:44 ...to breed the material for our targets.
00:21:47 And we had to radically change the way...
00:21:51 ...we choose...
00:21:54 ...the bombarding nuclei.
00:21:57 We had to find a new acceleration mode and a new ion source.
00:22:03 We had to do some hard work.
00:22:08 And now I would like to tell you...
00:22:12 ...that at the end of the 20th century...
00:22:18 ...and at the beginning of the 21st century the people of science understood...
00:22:23 ...that if they wanted to accomplish some ultimate missions...
00:22:30 ...they would have to work together as a team.
00:22:34 Imagine, a group of scientists is working somewhere far away...
00:22:38 ...in the other part of the world.
00:22:41 And they achieved good results with their equipment.
00:22:44 Another team somewhere in France...
00:22:48 ...got some results with other instruments.
00:22:52 But when we put their efforts together...
00:22:56 ...and utilize...
00:22:59 ...all the scientific accomplishments of the mankind...
00:23:05 we may get to an entirely new level.
00:23:09 And so, we decided to opt for this approach.
00:23:12 We brought an ion source from France...
00:23:15 ...and redesigned it to our needs.
00:23:18 We involved our American colleagues who ran a powerful reactor.
00:23:23 We asked them to breed this material for us.
00:23:27 We upgraded our own accelerator.
00:23:33 We developed a new technology to accelerate the ions of calcium-48.
00:23:39 We devised a whole new installation.
00:23:42 But then we didn't like it and we did it all over again.
00:23:46 We didn't like the new set-up either.
00:23:52 And so, we started to modify it once again.
00:23:58 At the very end of 1999...
00:24:05 ...in winter we conducted our first experiment.
00:24:10 The plutonium bred at the reactor in the US...
00:24:14 ...had to be bombarded by calcium-48, produced by the separator in the Urals...
00:24:21 ...in the ion source we received from France...
00:24:26 ...installed at the new separator system which was designed here.
00:24:30 And that was the very first time when we saw...
00:24:35 ...the fission of the element with the atomic number 114.
00:24:41 The fission took quite long.
00:24:44 You could even look at the watch.
00:24:46 Element 114 was stable for two seconds before decaying into Element 112.
00:24:52 Element 112 was stable for half a minute before decaying into Element 114.
00:24:56 I mean, Element 110. And Element 110 decayed spontaneously.
00:25:00 That was...
00:25:03 ...extremely unusual. Because the elements which were synthesized earlier...
00:25:08 ...like Elements 108 or 109, their half-life was just several milliseconds long.
00:25:13 Or several microseconds. Compared to seconds for Element 114.
00:25:17 And so, we saw that our latest theory was correct...
00:25:22 ...in the estimation of the half-life of these elements.
00:25:26 We felt truly encouraged.
00:25:29 After that experiment...
00:25:34 ...we lived another 10 years of our lives.
00:25:38 We got more confident and relaxed. We knew we would get the results.
00:25:42 We upgraded the sources and the accelerators and the equipment.
00:25:48 Our American colleagues bred more material for our new targets.
00:25:52 This is the way we produced a whole range of new elements.
00:25:58 We took full advantage of the reactor.
00:26:03 We took full advantage of our accelerator.
00:26:09 As a result, we produced Elements 113, 114, 115...
00:26:14 ...116, 117, and 118. The six elements.
00:26:21 You can ask me why six and not seven.
00:26:26 If the reactor could produce a heavier target...
00:26:29 ...we would have synthesized seven elements.
00:26:33 With an even heavier one we could produce eight of them.
00:26:35 The reactor has its limits.
00:26:38 Even the most powerful of all the reactors...
00:26:41 ...can't produce a target...
00:26:44 ...with the atomic number 99. The one with the atomic number 98...
00:26:47 ...gives us Element 118. But we can't have a target with the atomic number 99.
00:26:52 As a result, by now...
00:26:55 ...we can benefit from everything...
00:27:00 ...which was developed by our predecessors in different areas of physics.
00:27:04 In the physics of nuclear reactors and the accelerators...
00:27:08 ...and the physics of nuclear reactions. We did our thing. In this way, of course...
00:27:14 ...it is very good that we did it. But it is not only us...
00:27:19 ...who did it. This is also an accomplishment...
00:27:22 ...of many generations of physicists before us.
00:27:26 So...
00:27:29 Could you explain me...
00:27:34 ...an element? What is an element?
00:27:38 What is... - An element?
00:27:40 Could you explain it? What is an element? The element in itself? What is it?
00:27:46 We are talking about elements now.
00:27:50 But in fact, we produce atomic nuclei.
00:27:56 Whilst an element is an atom.
00:27:59 We trigger a nuclear reaction in order to modify the nucleus.
00:28:04 We convert a nucleus into a new one.
00:28:20 I am sorry. - No problem.
00:28:44 So I'll ask... No problem.
00:28:46 ...the question again. What is an element?
00:28:49 We convert a nucleus into a new one.
00:28:53 And when the new nucleus is synthesized, it attracts electrons.
00:28:58 And then this is an atom. This is a new element.
00:29:03 And then we can explore the chemical properties of this element.
00:29:09 Since we can explore the chemical properties, chemists come into play.
00:29:15 Let us remember the table of elements now.
00:29:18 This table is called periodic.
00:29:22 So we should place this new element...
00:29:25 ...in the table where its expected chemical properties...
00:29:31 ...in accordance with the fundamental Periodic Law...
00:29:36 ...would match this very position. What do I mean to say?
00:29:40 If we produce Element 112, it should be placed below mercury.
00:29:48 If you produce Element 114, it should be placed in a column under lead.
00:29:54 If you produce Element 118, it should be placed under radon.
00:30:00 This is what the Periodic Law is about.
00:30:04 But then we have to do one more thing.
00:30:07 We must check if these new elements are subject to the Periodic Law.
00:30:11 We have to conduct chemical experiments.
00:30:14 Not physical but chemical ones.
00:30:16 And we have to work with atoms instead of atomic nuclei.
00:30:19 Otherwise we can't answer this question.
00:30:23 Just imagine. Thanks to the fact...
00:30:29 ...that these new super-heavy elements exist long enough...
00:30:35 ...seconds instead of milliseconds...
00:30:38 we can conduct these experiments. And we did that.
00:30:41 We carry out these experiments nowadays, too.
00:30:45 The experiments proved that the placement of the new elements...
00:30:48 ...was correct.
00:30:49 Though their properties were a little bit different...
00:30:54 ...from those predicted...
00:30:58 ...by the Periodic Law.
00:31:02 These differences are caused by relativistic effects.
00:31:09 The electrons of a super-heavy atom are also very heavy.
00:31:13 We should keep that in mind when we explore the chemical properties.
00:31:19 The relativistic effects were always there with heavy elements.
00:31:25 I should mention that gold is what it is because of relativistic effects.
00:31:30 And mercury is a liquid metal because of relativistic effects.
00:31:34 With super-heavy elements these effects should be even more evident.
00:31:39 And they are. But still these elements can be placed in the table...
00:31:44 ...as predicted by Mendeleev and his Periodic Law.
00:31:51 And what can we do with the new elements?
00:31:54 What is it for the humanity? What does it mean what you are doing?
00:31:58 This is something I wanted to mention. In fact, it doesn't mean a thing.
00:32:04 Nothing. Because we can produce these elements...
00:32:08 ...in ultralow quantities. We can produce their atoms.
00:32:11 We are happy to produce an atom a day.
00:32:18 Or even an atom a month if we are talking about rare elements.
00:32:25 But anyway, we are sure that we produce them.
00:32:29 Because we record events which prove it.
00:32:35 We have got lots of things to do...
00:32:39 ...to thoroughly explore their properties.
00:32:43 This is why we should produce more.
00:32:46 10 times or even 100 times more. 1000 times more.
00:32:49 Then we could launch full-scale research programs.
00:32:55 And they won't be anything exotic. Just regular research work.
00:33:03 But if you want to do that...
00:33:06 ...you should take a pause and try to figure out what you should do next.
00:33:12 You can't do any research if you produce an atom a day.
00:33:16 Your life would be too short for that.
00:33:23 This is why we came up with a surprising question.
00:33:26 10 years later...
00:33:30 10 years after we started experiments with super-heavy elements.
00:33:36 What would be the way we would do the same things today?
00:33:41 Not 10 years ago, but today.
00:33:44 We produced some super-heavy elements. We know their properties.
00:33:49 We know the ways to produce them.
00:33:52 And we know the ways you can never produce them.
00:33:57 This is one side of this coin. We know something. We got some knowledge.
00:34:02 But on the other hand, we saw major technological advances in those years.
00:34:08 We have got different accelerators and different sources now.
00:34:13 And the computers are different.
00:34:15 Everything has changed a lot in those 10 years.
00:34:19 If we use our knowledge...
00:34:22 ...on the technological innovations of the previous 10 years...
00:34:28 ...we can produce 100 times more of these elements quantity-wise.
00:34:35 And we decided to build a factory to produce super-heavy elements.
00:34:40 We are building this laboratory now.
00:34:45 We hope to start the experiments at the end of next year.
00:34:50 Naturally, those experiments will be different from what we are doing now.
00:34:55 We don't know what these experiments will be.
00:35:00 Everything can change on the way. This is what science is about.
00:35:04 But something is clear.
00:35:08 We can use this facility...
00:35:12 ...to conduct 2-3 experiments a year.
00:35:14 And each of them will include thousands of events.
00:35:19 And then we will probably see something we can't see now...
00:35:25 ...because we don't have enough of these exotic elements.
00:35:31 This is our future.
00:35:34 But it means also that at this point we don't know yet...
00:35:39 ...what we can do with the new elements? Is that correct?
00:35:43 Yes, now...
00:35:44 At this moment, these new elements do nothing else...
00:35:47 ...but give us some fundamental scientific data.
00:35:52 They help us confirm...
00:35:57 ...that our knowledge of the atomic nucleus...
00:36:02 ...is correct.
00:36:04 The experimental results confirmed it in terms of quality and quantity.
00:36:13 The difference from the predicted values is within 5%.
00:36:17 The super-heavy elements...
00:36:19 ...proved 10 times more stable than predicted theoretically.
00:36:25 This is one major thing.
00:36:28 These experiments confirmed all the theoretical concepts.
00:36:35 Regarding the practical use of these elements...
00:36:40 I should say that the results of these experiments...
00:36:45 ...conducted here and in CERN...
00:36:48 ...are not of any practical use. These results are too hard to obtain.
00:36:55 You can hardly do it anywhere else.
00:36:59 The practical use arises...
00:37:04 ...from everything we do on the way.
00:37:08 You are forced to review a lot of things.
00:37:12 Sometimes you have to invent an electronic system which doesn't exist.
00:37:16 But you need it for your experiments.
00:37:19 Or you must design a plasma source which doesn't exist.
00:37:23 But you want it. Otherwise you can't do anything.
00:37:26 And there are a lot of things like that.
00:37:30 We must upgrade the chemical equipment...
00:37:33 ...which explores single atoms to define chemical properties of new elements.
00:37:38 We get a lot of spillover effects.
00:37:42 Imagine a drag behind a trawler.
00:37:48 And it brings you so many new fish.
00:37:52 Yes, we can aim for super-heavy elements.
00:37:58 Or they aim for Higgs boson in CERN.
00:38:01 But the research of the Higgs boson brings so many new things in other areas.
00:38:06 This is the practical use of this kind of research.
00:38:11 The point is that many talented people dedicate their lives to this program.
00:38:18 And this is what pushes the science forward.
00:38:21 I believe this is very important.
00:38:27 It's almost like alchemy.
00:38:31 Yes, by the way, this is also very interesting.
00:38:37 Of course, this research of new elements...
00:38:40 ...is sort of ancient alchemists' dream come true.
00:38:46 They wanted to turn lead into gold.
00:38:54 In order to accomplish this goal...
00:38:57 ...they heated lead, hammered it...
00:39:01 ...treated it with extremely corrosive substances.
00:39:06 They got it right that this transformation required energy.
00:39:12 But they could never understand how much energy they needed.
00:39:16 If they hammered lead at the speed of a tenth of the speed of light...
00:39:21 ...they could probably accomplish their goal.
00:39:25 The point is...
00:39:28 ...that if you want to convert an element into another one...
00:39:32 ...you have to convert its atomic nucleus.
00:39:35 It's not about electrons. It's not about chemistry.
00:39:38 You must convert the atomic nucleus.
00:39:41 That would mean a nuclear reaction. Alchemists couldn't do anything like that.
00:39:50 Can you explain me the island of stability?
00:39:54 Could you elaborate on that?
00:39:57 Well, this is...
00:40:00 The new theory put forward the following concept.
00:40:06 The higher the atomic number is or the heavier the element is...
00:40:11 ...the shorter its half-life is going to be.
00:40:17 But this trend will be reversed with very high atomic numbers.
00:40:24 Because the nuclear matter is not amorphous...
00:40:28 ...like liquid, like a drop of water.
00:40:31 It has some inner structure.
00:40:33 And this inner structure is the reason behind the increase of the half-life.
00:40:38 This increase...
00:40:42 This area where the elements will be stable enough was called an island.
00:40:50 Compared to the elements we have got now which are like a continent.
00:40:55 Hence this name.
00:40:58 This is why when we talk about super-heavy elements...
00:41:01 ...and you ask me where they are, I would say that they are on the island.
00:41:06 These are island elements, if I may say so.
00:41:11 Like Britain is an island. These elements are somewhat similar.
00:41:17 Right...
00:41:20 Another important point is that the peak of this island is pretty high.
00:41:26 The elements there may be very stable.
00:41:30 At the moment we deal with the isotopes...
00:41:37 ...which are decay products of these future elements...
00:41:41 ...and their half-life is 30 hours. Or a day.
00:41:44 But this is not the limit.
00:41:46 We should approach the peak of this island. But we can't do that now.
00:41:50 We put a lot of effort...
00:41:53 ...into reaching this island and stepping on it.
00:41:57 But now we must climb the mountain.
00:42:00 One of the goals we want to accomplish at our super-heavy elements facility...
00:42:06 ...is to climb this mountain.
00:42:08 Of course, we are destined to lose a lot on the way.
00:42:11 Probably, we will produce nothing but single atoms again.
00:42:15 But these atoms will be stable for a very long time.
00:42:18 And this is something we must do.
00:42:24 Since the half-life of these elements is so long...
00:42:29 ...can we probably find them in soil...
00:42:32 ...or in cosmic rays?
00:42:35 We still hope to do so.
00:42:38 We keep on conducting experiments...
00:42:43 ...under the Alps.
00:42:47 In the tunnel which joins Italy and France...
00:42:51 ...there is an underground laboratory with the Alps for its roof.
00:42:57 4000 meters high.
00:42:59 The Alps protect this lab from cosmic rays.
00:43:02 We work in a clean environment. And we can record extremely rare events...
00:43:08 ...of super-heavy elements decaying in the natural samples...
00:43:12 ...if they are present there.
00:43:15 The instruments we are using let us record...
00:43:19 ...even one decay event per year.
00:43:23 This is the thing.
00:43:26 Just imagine.
00:43:28 This is less than the concentration of gold or uranium in soil...
00:43:33 ...by about 17 orders of magnitude.
00:43:37 17 orders of magnitude.
00:43:41 Other methods...
00:43:47 ...Professor Flyorov developed...
00:43:50 ...provide for the search for these elements in cosmic rays.
00:43:53 Though not present in the solar system these elements may exist in outer space.
00:43:58 Or maybe these elements...
00:44:02 ...which were formed in the solar system 4.5 billion years ago...
00:44:06 ...are being formed on other planets right now.
00:44:09 And we can trace them in cosmic rays.
00:44:12 By the way, the composition of these rays is similar to those we find on Earth.
00:44:17 But they are younger.
00:44:19 And they may contain traces of these elements. This is another point.
00:44:24 I mean...
00:44:28 ...that we don't know how high the peak of this island is.
00:44:34 We don't know if this is the only island like this.
00:44:37 Or if there is another one made up of even heavier elements.
00:44:42 Those would be hyper-heavy elements.
00:44:46 But we should understand...
00:44:50 ...analyze and interpret or even predict this possibility...
00:44:54 ...through the research of the things we have obtained by now.
00:44:58 This is why we pin hopes...
00:45:05 ...on this super-heavy element production facility.
00:45:08 Factor 100 may help us...
00:45:12 ...answer this question. Or not.
00:45:18 In that case we will have to find some other way.
00:45:22 This is what scientific life is all about.
00:45:26 Are there many factories like this in the world?
00:45:30 None. This is the first one of its kind.
00:45:33 The very first one.
00:45:35 I hope there will be more. But this is the very first one.
00:45:40 This is the first factory?
00:45:43 We'll see how it's going to work.
00:45:45 If this concept proves attractive we'll have more factories like this.
00:45:51 And why is it built here? In Russia?
00:45:56 Why is it built here, in Russia? In Dubna?
00:45:58 But this is our idea and our concept.
00:46:04 We decided to stop and redo everything from scratch.
00:46:11 This is our idea and our design.
00:46:14 We designed the accelerator and the rest of the instruments.
00:46:19 Even the building. We designed it, too.
00:46:25 This factory should be around the corner.
00:46:29 Then I can stand up and go and see what's going on there.
00:46:36 We presented this project to the Scientific Council.
00:46:41 That was 5 years ago.
00:46:50 Even 6 years ago.
00:46:53 Of course, the project required significant financial investments.
00:46:58 It is a large-scale project. In fact, we were talking about a new laboratory.
00:47:03 With a new accelerator and a whole new set-up.
00:47:09 The Council approved the project.
00:47:12 And we received money to go on with it.
00:47:15 The JINR Scientific Council approved these investments...
00:47:22 ...into one of the most promising areas of research.
00:47:27 On the other hand, in the USA...
00:47:34 I went there twice. And we submitted a request to the Department of Energy.
00:47:40 And they approved our project, too.
00:47:44 The general feeling is...
00:47:48 ...that it is a promising program and we should carry on.
00:47:51 The factory will be another step forward in this direction.
00:47:59 That's a magical thing that you created. This factory.
00:48:06 No, this is...
00:48:09 I think this concept made sense.
00:48:12 It is based on everything we already did.
00:48:16 At some point we had to stop...
00:48:20 ...and choose our way. This is what we do in life.
00:48:27 But you are standing on the shoulders of people like Flyorov.
00:48:33 Well, yes.
00:48:37 I am really sorry Flyorov didn't live long enough to see it.
00:48:44 Neither Flyorov nor Seaborg in the US.
00:48:48 They desperately wanted to produce super-heavy elements.
00:48:52 And they did a lot...
00:48:55 They did a lot to make their dream come true.
00:48:59 But unfortunately, we found the right way to do it when they passed away.
00:49:07 Could you explain me about the elements?
00:49:11 How do you make an element?
00:49:17 If we want to transform an atomic nucleus I was talking about earlier...
00:49:22 And we have to do it to convert an element into another one.
00:49:28 Then we should manipulate it in some way.
00:49:35 One of the most obvious methods is...
00:49:39 ...for example to fuse two atomic nuclei.
00:49:44 We should bring them into contact.
00:49:48 And then...
00:49:52 ...the forces of nuclear attraction will...
00:49:54 ...make the bigger nucleus take up the smaller one.
00:49:58 This process is called fusion.
00:50:03 But first we have to bring them into contact.
00:50:06 Both nuclei are positively charged.
00:50:09 And we should find a way to overcome the repulsive force between them.
00:50:13 This is why we must accelerate the nuclei.
00:50:17 Their velocity should be high.
00:50:19 About one tenth of the speed of light.
00:50:23 And so, we need some machine to accelerate the nuclei.
00:50:26 This machine is called an accelerator.
00:50:32 Let's assume I would like to produce...
00:50:39 ...element with the atomic number 100. I would take uranium I can find in soil.
00:50:44 Its atomic number is 92. I will use it to make a target.
00:50:48 The target will contain atoms of uranium.
00:50:51 I would blast it with nuclei of oxygen.
00:50:53 But I will have to accelerate the nuclei of oxygen...
00:50:56 ...to the velocity of one tenth of the speed of light.
00:51:00 I can't accelerate oxygen as is. Because it is neutral.
00:51:04 I want its nuclei to be charged.
00:51:06 Then I can use an electric field to propel them.
00:51:10 This is the reason I have to inject the oxygen into plasma...
00:51:15 ...which will strip electrons from the nuclei.
00:51:18 Without an electron a nucleus will have a charge of +1.
00:51:21 Without two electrons it will have a charge of +2 etc.
00:51:28 The hotter the plasma is the more electrons I can pull away.
00:51:32 This is what I call an ion source.
00:51:36 It helps us convert a neutrally charged atom into an ion with a positive charge.
00:51:41 Then I am taking this ion out...
00:51:45 ...and I am putting it into an acceleration chamber.
00:51:51 The ions accelerate in an electric field.
00:51:56 You have to apply an electric field to propel them.
00:52:00 There are two ways to do that.
00:52:03 You can build a very long accelerator...
00:52:08 ...with the electrodes placed along the pipe.
00:52:11 Slow particles will be propelled to one tenth of the speed of light at its end.
00:52:16 Or you can make the particles travel in a circular path.
00:52:21 But you need a magnetic field to do that.
00:52:24 You need a large magnet like those you can see in the accelerators.
00:52:28 They hold the ions to their trajectory.
00:52:31 This magnet is about 4 meters in diameter.
00:52:34 It generates a magnetic field.
00:52:40 It makes the ions travel in a circular path.
00:52:43 There are also two electrodes which generate an electric field in the chamber.
00:52:48 The electric field accelerates the ions.
00:52:52 But you need to synchronize the process.
00:52:55 You need to accelerate the ion here...
00:52:57 ...and accelerate it again half way through the circle.
00:53:01 This is the reason we want alternating voltage.
00:53:04 It is alternate and not constant.
00:53:08 The voltage cycles should be in sync with the movement of the ions.
00:53:13 Accumulating energy of the ion will make it move outwards.
00:53:19 Its trajectory will look like a spiral path outwards from the center.
00:53:24 And when the ion reaches the rim...
00:53:26 ...two meters away from the center it will accumulate the maximum energy.
00:53:32 Then we should take the ion out of the chamber and send it to the target.
00:53:37 It is the operating principle of an accelerator.
00:53:40 It is called an orbit accelerator or a cyclotron.
00:53:44 The particles travel in a circular path. Their trajectory is spiral.
00:53:48 This spiral path is several kilometers long.
00:53:54 An ion completes about a hundred circles.
00:53:59 And this is enough to propel it to a one tenth of the speed of light.
00:54:04 Then this ion can come to the atomic nucleus of uranium close enough.
00:54:10 They can fuse.
00:54:13 As a result of this fusion we can add up...
00:54:17 ...Element 92 and Element 8 to produce Element 100.
00:54:22 Of course, there's a chance that they won't fuse. Or some may fuse partially.
00:54:28 But these will be side effects and products we are not interested in.
00:54:35 And we should get rid of those...
00:54:37 ...to see what we want to see. And we want to see Element 100.
00:54:42 When we talk about super-heavy elements...
00:54:47 ...we should get rid of a trillion of side products.
00:54:52 A single atom and a trillion of side products.
00:54:55 This is the reason these experiments are so complicated.
00:54:59 We must ensure ultimate selectivity.
00:55:04 And so...
00:55:07 ...this process...
00:55:11 ...of accelerating, bombardment, and fusion...
00:55:15 ...is the principle behind the production of super-heavy elements.
00:55:19 There is another issue with super-heavy elements.
00:55:22 I gave you an example of uranium.
00:55:26 We can find uranium in soil.
00:55:28 But we want artificial elements to produce super-heavy ones.
00:55:31 And they don't exist in nature.
00:55:34 Plutonium, curium.
00:55:36 You need a very powerful reactor to synthesize those.
00:55:40 And so, you utilize both reactors and accelerators.
00:55:44 You want a reactor to produce a target.
00:55:49 You breed material for your target there.
00:55:53 Then you place the target into your machine.
00:55:56 Then you accelerate the ions to produce new elements.
00:56:02 This is what makes these experiments so complicated.
00:56:05 They get even more complicated when the half-life of the target is short.
00:56:12 On the one hand, you want more neutrons in your target.
00:56:17 On the other hand, the more neutrons you have the shorter its half-life is.
00:56:22 We set a record.
00:56:25 I mean the element with the atomic number 117.
00:56:29 The target was made of berkelium.
00:56:31 The half-life of this isotope is 300 days long.
00:56:37 This is why when we prepared this experiment...
00:56:41 ...first, we had to breed enough material.
00:56:45 And the reactor should have been powerful enough.
00:56:49 Then we had to separate the material chemically.
00:56:54 Then we had to bring the isotope from one hemisphere to the other one.
00:56:59 Then we had to install the target...
00:57:01 ...and bombard it for another 300 days.
00:57:08 When we got our first results, many American colleagues said...
00:57:12 ...that it was a tour de force.
00:57:18 Other isotopes had longer half-life. Working with them was easier.
00:57:25 This is more or less what it looks like.
00:57:29 Ok. I understand. Could you also explain to me in simple terms...
00:57:33 ...what is the classical theory?
00:57:36 This is a very good question.
00:57:45 The history of nuclear physics...
00:57:50 ...dates back...
00:57:53 ...to March 7, 1911.
00:57:57 That day Ernest Rutherford attended...
00:58:03 ...a meeting of the Manchester Philosophical Society and said:
00:58:07 'I believe this is what an atom looks like.'
00:58:10 'There is a small and dense nucleus in its center.'
00:58:15 'It is positively charged.'
00:58:18 'And the electrons orbit it at some distance.'
00:58:21 'And they are negatively charged.'
00:58:24 Nobody could understand the structure of the atom before.
00:58:29 There are electrons which are charged negatively.
00:58:32 But an atom is neutral. That means there is something positively charged inside.
00:58:36 But how can positive and negative charges co-exist?
00:58:41 The opposites should attract and annihilate.
00:58:47 Rutherford likened the atomic structure to the solar system.
00:58:52 Planets orbit the Sun. But it's all about gravity in space.
00:58:56 And here we deal with electromagnetic interaction.
00:59:00 The dense nucleus is charged positively.
00:59:03 And the electrons orbit it.
00:59:10 His concept was not immediately understood or accepted.
00:59:18 But as the physicists including Rutherford himself looked into the issue...
00:59:23 ...they discovered proofs of this concept which was called a planetary model.
00:59:35 In fact, the nucleus is small, round, and dense.
00:59:42 The nucleus is incondensable.
00:59:45 You can't condense it.
00:59:48 Ions bounce off it but can't condense it.
00:59:53 And then, back in 1928...
00:59:56 ...our compatriot...
01:00:00 ...who later became a famous American scientist, George Gamow...
01:00:07 ...said that a nucleus is similar to a drop of liquid.
01:00:16 To a drop of water. Though a tiny one.
01:00:20 But it's denser than water by 15 orders of magnitude.
01:00:26 And he suggested a liquid drop nuclear model.
01:00:30 In fact, a nucleus has got a distinct shape. It is spherical.
01:00:38 It is incondensable.
01:00:43 I would call this a rather bold metaphor.
01:00:49 Because a liquid drop is a macro object.
01:00:53 And a nucleus is a micro object.
01:00:57 Macro objects are subject to Newton mechanical laws.
01:01:01 Micro objects are subject to Einstein laws.
01:01:05 And we compare a nucleus to a macro object.
01:01:13 But that model proved extremely efficient.
01:01:20 It helped us predict the discovery of atomic binding energy.
01:01:24 It likened particles to molecules of water.
01:01:27 It helped us predict the fission phenomenon.
01:01:36 It helped us predict some decay events.
01:01:41 In this way it is a classical one.
01:01:44 We apply a classical metaphor of a liquid drop to a nucleus.
01:01:49 But...
01:01:51 ...a liquid drop is amorphous.
01:01:54 It has got no inner structure.
01:01:58 And later we found out that a nucleus has got an inner structure.
01:02:02 This inner structure is the only reason we can produce super-heavy elements.
01:02:07 Without it we could never produce any of them.
01:02:12 Because the classical theory likens a nucleus to a liquid drop...
01:02:17 ...and gives us an exact limit. There can be no elements heavier than 100.
01:02:23 All the heavier ones were produced because the nucleus has a structure.
01:02:28 The matter has got its inner structure.
01:02:33 I am going to try and help you visualize this structure. Imagine a liquid drop.
01:02:38 And now imagine a snowflake inside this liquid drop.
01:02:43 The snowflake is sort of a carcass.
01:02:48 It may be tiny but it is still a carcass.
01:02:52 And when you approach the limit of nuclear stability...
01:02:56 ...when the repulsive forces of positively charged protons...
01:03:01 ...equal the attraction forces...
01:03:04 ...this tiny carcass makes a very heavy nucleus stable.
01:03:11 This is the fundamental base of the island of stability of super-heavy nuclei.
01:03:18 This is what the classical theory is about.
01:03:21 The later theory which considers the atomic structure...
01:03:24 ...was called a microscopic theory or a quantum theory.
01:03:50 This is something we can call the body of evidence of the nuclear physics.
01:03:57 For the last 3.000 years. Everything we know today.
01:04:02 Some experts say that we can go back to 6000 years.
01:04:06 Just imagine the potential.
01:04:10 The black squares here are...
01:04:14 ...the nuclei of the elements which occur naturally in soil.
01:04:18 They were formed with the Earth itself...
01:04:21 ...4.5 billion years ago.
01:04:26 You can follow these black squares up to lead and bismuth.
01:04:33 There are no black squares after those.
01:04:35 You can see a narrow neck...
01:04:37 ...and an area we call a peninsula.
01:04:44 You can see some black squares in the middle of it.
01:04:49 These are thorium and uranium.
01:04:51 They came into existence together with planet Earth, too.
01:04:56 But they decay right before our eyes.
01:05:02 Both thorium and uranium are radioactive elements.
01:05:05 And this is the end of it. No more black squares.
01:05:08 The colors turn light.
01:05:14 It's almost white now.
01:05:15 That means that the half-life of these elements is very short.
01:05:19 You can see 22 grades of their half-life.
01:05:26 From black to blue.
01:05:29 The blue color stands for the atoms...
01:05:31 ...with the half-life of less than one microsecond.
01:05:35 The black color stands for stability. Lead is the last black square.
01:05:39 It is followed by the peninsula with uranium and bismuth on it.
01:05:43 Then we see transuranium elements which are produced in the reactors.
01:05:49 These are the elements bred in the US reactors...
01:05:52 ...which we bring here to make targets and produce super-heavy elements.
01:05:56 And if you look even higher you can see a small sand bank...
01:06:03 ...and a big island. This is the island of stability.
01:06:07 The island of stability of super-heavy elements.
01:06:10 This island is a concept which haunted scientists for many years.
01:06:15 Does it exist or not?
01:06:18 Yes, it does exist.
01:06:21 We stepped on this island and we produced six elements...
01:06:27 ...and 16 different nuclei or isotopes of these elements.
01:06:31 We probed this island in many places.
01:06:34 And we proved that it is in fact an island of stability.
01:06:40 This is what it's all about.
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