 Okay. Good morning, everyone. Looks like the morning starts slowly. No secretary, no luggage for me. And I hope you had a nice weekend. My name is Daniel Sridikas. I'm coming from IA. So I'm replacing the former colleague of mine, Stanislav Simakov, who was with you all last week. And I heard you had a very productive and interesting week in terms of lecturing, information you gathered, new friends you met, and the future of nuclear data you discussed, right? So is that everybody has your friend after the weekend or we're still waiting for somebody? Is somebody missing? Raise the hand. Okay, so we can start. I will speak to you a little about nuclear data, but rather where nuclear data is used. So I will speak about research reactors, which are mainly the source of neutrons. Try to introduce that, bring that bias with the nuclear data, and then come back to also some accelerator-related applications or joint applications by research reactors and accelerators. So as I said, Stanislav comes from nuclear data section. We belong to the same department of nuclear science and applications. I belong to physics section, and in physics section we have support to the applications of research reactors, applications of accelerators. We have fusion-controlled project support. We also have materials research, and as a cross-cutting activity, we have support to everything that goes to instrumentation. So that's a little bit outline of my presentation. I will stop somewhere in the middle, so then we can discuss a little bit the part which was covered already, and we'll continue with the general aspects after the first part of the lecture. So I will start with a historical background, introduce you very briefly applications of research reactors, what are the future perspectives of these devices, and provide these preferences. Certainly you're aware what nuclear reactor is, and you can recognize the components as a reactor fuel, reactor vessel, neutrons need to be moderated, so you have moderator and coolant, you have control rods to control the chain reaction, you have a containment and a cooling tower. So a research reactor also produces energy in terms of heat, but it does everything except electricity generation. So the main purpose of research reactor is to use neutrons which are available. To understand how a research reactor works in general, you need to understand some basic nuclear physics. So certainly you're experts now on interaction of neutrons with matter, you're aware of fission, capture and scattering, this is all the work about here. Then once you learn about that, you will get to know the concepts as criticality, the role of delayed neutrons, radioactive decay, and basics of thermohydraulics. So this is normally taught in some nuclear engineering class at the bachelor level, and I hope and I assume that you know most of all that. A little bit of history. So history of controlled fission starts with 1942 in the Chicago Pile Facility, managed by Enrico Fermi. So in parallel, similar efforts were done in the Russian Federation in 1946, F1 also graphite moderator facility, the team led by Kurchatov, and as you see in both cases, objective was to create neutrons for plutonium production. So the purpose at that time was very specific, and this is where the research and efforts were taking place. Now the first concept or name of facility called a research reactor took place a bit later in Chock River laboratories. NRX National Research Experiment Reactor went critical. It was 20 megawatt facility, so quite intensive neutron source, and it was for the first time used for basic research. And when we say basic research, in particular for the cross-section data measurement. So let's come back to the features of research reactor. So these are typically very small cores, compact cores, has small volumes. Many of them have powers less than 5 megawatt thermal. Compared to power plants, they use high enrichment fuels, typically up to 20% enriched in uranium 235. They can have either natural force cooling depending on the power levels, and some of them do have pulsing capabilities. So you can run not only in continuous mode, but also in a pulsed mode. Again, the purpose is to produce neutrons and provide access to these neutrons. So this access can be provided. You can see typical reactor core right here, where is what we call active zone. This is the one where the nuclear fuel is located. This is where the most intense fluxes of neutrons are produced. So these neutrons can be accessed inside the core, along the core boundaries, or extracted to external beams outside of the shieldings. I mentioned you the power of research reactors ranging from 100 kilowatts to 10 megawatts. And the fluxes available within the core zone are from 10 to 12, 10 to 14 neutrons per square centimeter per second. What are the applications of research reactors? So this book, Applications of Research Actors, was published last year. It's updated catalog of research act applications, and it ranges, you can see here, from education, training, neutron activation analysis, radioisoproduction, geoprology. All of them I will try to cover in two slides. Each of them, for each of these applications, I will dedicate two slides just to introduce you and provide further literature if you're interested to learn more about them. To learn more about research actors themselves, you can go to our research reactor database. You can find research reactors based on the regions or countries they are located. You can check the status of the operational shutdown or under construction. You can also look, depending on the categories, based on the power, flux levels, age, or utilization pattern. And last but not the least, you can look which reactor is doing specific applications. For example, if you say I'm interested to using a research reactor for neutron scattering, by searching through neutron scattering, you will find out the list of research reactors where these experiments are taking place. And in many cases, also contact details how to contact these facilities if you would like to propose and carry on experiment. So today, out of more than 700 research reactors constructed worldwide, we count 247 still operational. And as you can see here, research reactors geographically are distributed all over the continents. Even Africa has close to 10 research reactors operational today. So the leading countries in number of research reactors are Russian Federation, United States of America, China, France, and Japan, where they have more than 10 research reactors. I see most of you looking here because it's a bit different from this one. So as I said, this is the list of research reactor applications, and this is number of research reactors worldwide who claims that we do have this application in place. So as you see that most frequent applications of research reactors remain in education and training, neutron activation analysis, radioisotoproduction, neutron radiography. So who are users of research reactor and stakeholders? Well, of course, the government is the major stakeholder of research reactor because this is where the policy is defined. This is where funding comes and this is where further development of the facility depends on. Now, research reactor certainly relies a lot on scientific organizations and universities. This is where research and technology is concentrated. In addition to that, research reactor provides services and products to industry, agriculture, in energy sector, in medicine, and you will certainly learn about it after this presentation. So let's start with first application, which is education and training. So education and training, it can have different aspects and different levels. It can be just a promotional visits by students or pupils of the schools or even tourists. But when you go deeper, certainly research reactor is used as a teaching tool and provides, in many cases, hands-on training to understand reactor physics, neutronics, kinetics, thermohydraulics, et cetera. So it can teach even non-specialized students like biological science students. Of course, then it goes to the details and provides teaching for radiation protection, radiological engineering students, nuclear engineering students, nuclear power plant operator training, et cetera. As I said, it can look just a walk through the facility, go to the control room and get inside how things work, even touch some of the instrumentation and control units, or spend two weeks at the reactor and really do some hands-on training, working with the fuel, making different configurations, making reactor critical, doing some measurements and experiments, et cetera. So that's what is all about education and training. When you go to the nuclear power program, certainly a big number of stuff needs to be taught and educated. And education, again, starts at the very academic background, where universities come in preparing bachelor's, engineers and masters. But that's an academic training, basic training. Now, when you go to the nuclear sector, you will have a dedicated nuclear training, and after having all these diploma, depending on the positions you will occupy in the future nuclear power plant, you will need additional training from three, nine months, even up to two years, to learn on-job training depending on the position you will take. So just to have an idea how many people a nuclear power plant needs, this is example of two nuclear power plants, meaning two reactors at the same location, same site, you need somewhere between 1,200, 1,400 people altogether. So if you're going, your country goes to nuclear power, that means you need at least five, six, seven years to develop and train necessary people in this particular area if you have enough people graduating in the right universities and diploma. Second application, again, is very frequently used, is the neutron activation analysis. So the basis is that this technique allows qualitative and quantitative analytical analysis for determining trace elements and impurities. So in terms of samples, you can go from milligram to kilogram level and you can detect concentration of the levels of PPV. So this is an example, actually this is a map of the country, Jamaica, and you can see clearly here the cadmium distribution, which is resulting from the sampling of soil all over the country. So you certainly should understand that such maps of the country or areas is necessary. You can look and analyze the pollution, agriculture sector. Other samples can be rocks, minerals, atmospheric high results, tree rings, dust, ice cores, hair, nails, skin, plant, animal, matter, coal. So in all these areas you need analytical analysis, getting impurities at high precision. How does it work? You start normally with the sampling. When the samples are prepared, you do some irradiation of the reactor. So this is where the flux concept comes from and then after irradiation you create redactivity and do that measurement typically with the high precision, high resolution germanium detectors. You calculate elemental concentrations and you provide final reports, either being for your research project or to the client. So this is a typical flowchart of neutron activation analysis taking place. A very important role of research reactors is that neutrons are also used to produce radioisotopes. So radioisotopes are used in two main sectors, is medicine, mainly for diagnostics and therapy, but also in industry, agriculture and research. So for your detector of efficiency or calibration, for example, is certainly using various radioisotope as a source and these are mainly produced in the research reactors. So for example in medicine, molybdenum 99 occupies a very important place because on this single isotope 85% of all diagnostic procedures taking place. So if the cancer or tumor is about to be detected in a human being, there is a very big chance it was done using molybdenum 99 as a radioisotope for diagnostics. So as you can see here, this is a pure example where neutron data is important is that the radioisotopes can be produced by different patterns. So either these are short-lived fission products, meaning you will create fission inside of the reactor in the targets. You can also create through capture. That's a route to creating cobalt, for example, as a source. You can also use threshold reactions like NP and alpha or even the high flux reactors, you can use multi-stage captions. So first caption and then double-capture, et cetera. And of course in all these cases you need to know cross-sections. This is where your field comes. Now similar like in the case of neutron activation analysis, you would start the target fabrication, irradiate the targets in the reactor core, transport them to radiated targets through radioactive laboratory, hydrochemical processing, extraction, separation. Very important in particular when it goes to the medical sector, the quality control of impurities of such a target and quantities which are produced and then you just transport them in a final form to the end users. Research reactors also are used as a source of neutrons to help with the dating aspects and depending on the rocks or minerals you're going to date, if they are actinide free or including actinides, there are two different techniques and I will briefly explain what are these techniques. So the purpose here is to go and make geological studies on the origin and thermal history of different mineral deposits, volcanic terraces, formation of earth crust, et cetera. So the good thing is a powerful technique. It can go very back to the past and identify and date different rocks and minerals. So there are two ways to do that. One is when I said if the sample doesn't contain actinides, meaning nothing fissions inside, you can do that by artificially creating and looking at the ratio of argon and potassium. So this you would use typically NP cross-section from potassium to create argon 39 with a threshold 1.2 MeV. Or if the sample has a fissile material, then you would just look to the fission tracks and count fissions taking place and backdating using uranium 238 ratios. A very important application. I'm sure now in this room everybody has a cell phone and to produce good semiconductors, actually, research reactors, are still indispensable to dope silicon and implement some of the phosphorus impurities. So research acts are used for transportation doping of silicon. In some countries, research reactors also use to color different topaz. That brings also added value and you can use that as a jewelry afterwards if the stone doesn't become too much activated. So how this is done, you see you rely on a single reaction of silicon crystal by creating phosphorus impurities. So this is typical size of silicon ingots the way they are installed in the channels and irradiated. You have to make sure that neutron flux is quite homogeneous you want to have it doped for phosphorus impurities in a homogeneous way. In a similar way you have to apply different doses and temperatures so your gemstone gets the color doesn't become too black depending on the doses it receives. Let's come to a little bit to the energy applications. So research reactor certainly is a neutron source and present and future nuclear power plants are equally neutron sources. So let me spend one minute on this slide. So here we have material displacement damage in DPAs and here we have a temperature. So these are two important parameters for development and resistance of materials when it comes to the neutron irradiation and also to the temperature impact these materials can receive. If you look at the present technology this is where our best knowledge is that means we are staying somewhere below 50 DPAs and below 400 degrees. So this is where present nuclear power stays with some exceptions. When you look to the future proposed concepts all of them will require materials with much higher resistance to the irradiations and also to increase the efficiency or even to produce for example hydrogen desalinate water you will need higher temperatures. So all new concepts actually falling out of this what we call known region and that means that you need to create artificially these conditions to prove that materials proposed for new technologies will comply with the requirements with these new conditions. So you need to select materials, characterize, qualify before license can be issued and new facilities built on industrial scale. And actually research reactors can help in that respect because they provide much higher neutral fluxes meaning you will get much faster rates of DPAs to test your materials. In a research reactor you can create dedicated irradiation loops where in terms of pressure, temperature and even some different environments in terms of say liquid metals or gases you can create locally conditions corresponding the experimental conditions which would correspond to the future requirements for the future power plants. So I hope you will get a message that research reactors are important for the future nuclear power generation for technology developments. For the data I don't think I need to explain to you many of you or most of you most probably do experiments based on accelerators but some of you still using research reactors as a neutron source where you do this type of measurement. So certainly you can use neutrons for fission capture cross section measurement, branching ratios, neutron multiplicities, fission yields, decay data, delayed neutrons etc. So these are examples typical measurements done at research reactors on a bismuth capture cross section leading to the polonium production. These are typical total decay heat curves and these are the fission fragment measurements of different octanide or minor octanide targets. How this is done depends on the quantity you want to measure. You can first irradiate and then perform alpha-beta-gamma spectroscopy. You can do some measurements online if you know some of the materials which is your reference materials and I think you learned something about fission chambers here and this is also one of the instruments how to perform the measurements. Now for the fission fragment measurements you need a bit more sophisticated devices like this one installed for example in Grenoble in France. Neutrons are also actually can be used to produce positrons. So it's not direct usage of neutrons but neutrons are used to be converted to positrons and positrons used actually for various material surface research. So positrons can be used as a particle probe to detect defects in materials, examine defects in lattices and it's also very sensitive technique to analyze different surfaces when it comes to materials research. How this is done by research reactor so actually you interact with the heavy metal neutrons and gammas or you would go and have a copper as a converter to produce positrons. So afterwards positrons using electric or magnetic fields are concentrated and guided to the lab to perform positron beam analysis afterwards. But you see I don't know how many of you knew but at the beginning there is neutrons which are actually used for this particular. Maybe some of you also heard that neutrons can be used for neutron therapy. Again this is one of the examples when it's not used directly so it's not neutrons who are going to radiate the tumor of the human being but first there is a boron concentrate which is injected in the tumor so neutrons through the N-alpha reaction will help to burn the infected tumor cells inside the human being. So you see that there is many items to be addressed in this particular issue is that we need to see what we call three figures of merit, how deeply neutrons can penetrate, what is the dose ratio, how the borated substance is distributed in the tumor making sure that non-tumor cells are not affected or affected to the minimum. And actually this is not why this bread technique since the first irradiations backing back to 20-25 years ago there are only less than 1,000 patients treated using this technique mainly in Finland and Japan. So I mentioned you work a lot on a dose phantom to see how really those can be distributed. Then you can see here a reactor core, a lot of shielding, patient positioning here then boron substrate is injected in the tumor and the patient is irradiated. Of course in advance by calculating expected doses to be received by the tumor. This is one of the last examples I wanted to show you is the use of neutrons for neutron radiography. So today with the technology in digital imaging actually this is very powerful technique to get two-dimensional or even three-dimensional pictures inside of different materials and objects. It's a non-destructive technique. Today with the resolution you can go down to 10 micrometers level and you can see that the various applications can be used in biology. This is for example studies of the intake of water in a plant. It can also observe the batteries and different mineral distribution in the stones. You can have a dynamic radiography to observe how the lubricates are distributed in the running motor of the car or of the motor. This is an example showing the advantage of neutrons compared to X-rays. So you can actually see what is inside the object and even reconstruct and make a different cuts in 3D to estimate this inside object volumes etc. Neutrons and radiography in particular is also used as quality control, quality assurance technique. So this is example how the brazing connections are reconstructed and it allows to decide that some parts are not well glued actually. So this is part of the quality control. How it is done? You clearly see the neutron source. The neutron source can be reactor based or accelerator based. In some cases you would have cold neutron source so to make neutrons slow down then you will have a channel for neutron transporting with a number of collimeters and then before it arrives actually to the object and you have your digital camera installed to take the images and do post-processing imaging reconstruction. So I will take a break here if you had any questions before I go to a bit more fundamental science. Yes, typical neutron flux used at neutron imaging facilities is from 10 to 6, 10 to 7, 10 to 8 neutrons per second square centimeter. So the answer is yes. There is no free activation. Something gets activated but at these fluxes the activation is minimal. So I would say 99.9% all objects which are placed as experiments in neutron imaging returning back to the museums, to the schools, to where they come. That's why we still call it non-destructive testing. In some cases when the sample composition is not known you would do a short pre-radiation and then to perform some gamma scanning to see if by any chance you create some long lived products and some nasty products so then you would not perform real scale experiment. But in many cases these fluxes are too small to really activate something. There are some neutron sources. It is a transport patient. I mean for example we have an object we cannot do. Yes. We cannot study this object. Right. There are some sources. Yes. So you say it's not to mountain to Mohamed, it's Mohamed to mountain here. Yes, there are transportable neutron sources and these are based on decay sources, spontaneous fission like californium for example. But more and more today they used DD or DD generators which would produce energies of neutrons somewhere above 2 MeV or 14 MeV. And these are very widely used today for example in the oil industry. Also in the mechanical engineering in construction industry to see if the bridge has no breaks or whatsoever. So this is actually is really used today. So yes you can and today with these generators you can attain the intensities of say 10 to, I'm looking now if there are any experts in the audience in the last row here. But I think 10 to 9, 10 to 10, neutrons per second over 4 pi you can create with these sources. Which is sufficient to do just very quick transmission measurements and get quality of the objects you want to examine. So who works at ResearchEactor? Who does some experiments at ResearchEactor? So we have some experts right here. Okay. Can I continue? Yes. So now the neutron scientists would not speak about what I just said in the first 40 minutes. The neutron scientists would say I use neutrons to study materials. And then you go to a bit higher level of basic fundamental physics to understand what does it mean. Okay. I just explained your application, practical applications which you can touch, you can reach, et cetera. But here why neutrons are used for scattering because neutron scientists will tell you neutrons have right wavelength. Neutrons see the nuclei. Neutrons see light atoms next to heavy ones which is not the case in case of fixed ray for example. Neutrons can measure the velocity of atoms. Neutrons penetrate deep into the matter. They have no charge. So that's the way it goes. And because of the spin, neutrons see elementary magnets. So all these properties neutron scientists use in the scattering techniques. And that's why by changing the temperature where the neutron is located actually you can reach very different levels of your technique in terms of objects you can study. You can go from the level of centimeter down to the angstrom and that opens very broad area of materials research you can do. And these are the examples. So in 1994 the Nobel Prize in physics was given to two gentlemen for a very basic idea. They say neutrons can show where the atoms are and this is basis of elastic scattering. So it tells you by measuring scattered neutron location of the atom. And if you add in elastic scattering it even can tell what atoms do. So you see you can go very atomic scale and you can learn about materials using these two. What are the observables? Actually what you measure by sending neutron to the target you measure the angular distribution or energy distribution. And by putting these together by seeing if energy has been changed meaning you have an elastic scattering having angular distribution you can reconstruct and tell a lot of things at atomic scale what is happening in your sample. So how this is performed that's why you need a different energies of incident neutrons. That's why you have a concept of cold thermal and hot neutrons. You have neutron beams coming out from the core well collimated through the neutron guidance mirrors and ports. You have quite sophisticated neutron scattering instruments and different branches of neutron scattering techniques like diffraction, interferometer, straight scanner. Radiography is one of those but radiography is actually just looking at the transmission rather than interaction. Again you manage the data and analyze and interpret samples. So this is an example of the reactor equipped with a number of beam ports. You see the core is here and around the beam ports at various distances you have these neutron scattering instruments. This is I believe a small angle neutron scattering chamber located the reactor in the Helmholtz centrum in Berlin. So this is one part of the story. I also wanted to tell you it's not a secret that neutrons can be produced and we're discovered by using accelerators actually. So that brings back you to the 1930s which had we first discovered the neutron and accelerators were used in this particular case. This is 1940s, early 40s. Chicago Pile 1, Chicago Pile 2 when the first controlled fission reaction took place and very quickly neutral research reactors were able to provide very intense neutron sources reaching to the levels of a few 10 to the 15 neutrons per second square centimeter. However, you can clearly see that this source intensity became quickly saturated and it doesn't really increase for the last 50 years or so. And the reason for that is stated here that reactors have reached the limit at which heat can be removed from the core. So that means there is a technological, without a technological breakthrough the research reactors will not be able to provide higher fluxes than they available for the last 40 or 50 years. There is a small calculation here. I will come back to that a bit later. How many neutrons you produce at one megawatt fission power and how many neutrons you produce at one megawatt of the spallation reaction power. Now, spallation sources or accelerator based sources, they manage to go above this limit. However, this picture should not be understood. I would say there is one precaution that these sources actually provide you very intense neutron fluxes but these are pulsed sources. So that means you can access much higher by two, three orders of magnitude flux compared to the research reactor but for very short time. And this is what brings complementarity from accelerator based sources that you can study in containers very intensities and use different techniques, different aspects including neutrons. So let's come back to the neutrons produced at reactors. This is the basis how the neutron fissions, you get a number of neutrons coming out. Some of them I use to continue and run the chain reaction. And this is a calculation, simple calculation which is always good to know how many neutrons you can emit or produce keeping in mind that your reactor runs at certain thermal power. This is just for comparison. And this remains an interesting approach. So developing countries are continuing considering research reactor as a neutron source for many various purposes. Radioisotope production, silicon doping, neutron beams, neutron activation analysis. Last but not the least, in many countries, what we call a newcomer countries is considered a research reactor as a first step towards national nuclear power program. So the infrastructure is in place, people are trained, you come from small scale, low power reactor which serves as a technological center to go later on to the nuclear power technology afterwards. So this is the case of Jordan for example. Now when it comes to spallation, you need an accelerator. You will excite nucleus, you will get big number of neutrons evaporated and you will also notice that in terms of energy these neutrons might reach kinetically possible highest energy which the incident proton or neutron brings to you. So these are in a way different energy spectra you can obtain while on average these are pretty much similar energies when it comes to the average neutron energy coming out. Now I showed you the scale of research reactor. Research reactor is very small. It is tens of centimeters active core, then you have moderator, then you have a shielding, typically research reactor. Actually two research reactor can fit in this room. So just to tell you the scale, then you will have a shielding, a bit thicker walls than here, well a bit still thicker walls than here. It's somewhere deep. You have five, six meters of water so you can see the sharing of light from the top. So you see this is all the scale was speaking maximum about tens of meters. Now for equivalent neutron source based on accelerator you need at least 200, 300, sometimes 400 meters for your accelerating machine. Then I will show you what are new technology targets you need to develop to have comparative, comparable neutron sources created by accelerator. I think you had a presentation from Japan most probably this project was explained to you, J-PAC facility or if not I will just briefly tell you. So this is how the accelerator looks like. This is typically 300 meters long. Then it goes to the target area where neutrons are produced and the target looks like this. So this is a liquid mercury target about 20 tons of liquid mercury circulating and taking away the heat the primary beam brings. This is 3GV protons. So this is you see the size of the people typically 2, 3 meters long target and quite sophisticated technology to have it available. So of course when the target operation even when the target is not operating no people allowed to work around because of the neutron fluxes and radiation created in these areas. And again these are just all instruments installed or being installed in J-PAC facility as I would call maybe second or third generation neutron spallation source. So why these two technologies need to compete? I don't think they really need to compete but they can bring something together. And this is where people are working on the so-called subcritical reactors where the external neutron source is coupled to the subcritical core. And there is ongoing project Belgium and also European project called Mira where such a reactor would never in principle go critical. So this is advantage bringing external neutron source. You would not need to think about neutron economy. So you could load in terms of fuel whatever you wish even maybe nuclear waste. So that would allow you to transport nuclear waste. Now you will certainly produce a lot of neutrons. So why not using these neutrons for radioisotoproduction, silicon doping, material fuel studies, etc. So that becomes again a typical neutron source with various applications you can imagine. Another example of combined research reactor and accelerator research is in the area of producing super heavy elements. I don't know how many of you heard about super heavy elements. It's a so-called stability island where these elements can exist. So as you see this is an example. All these experiments on discovery at least on this example were done in joint research center in Dugna. But as you can see that in all cases calcium 40 as a beam, calcium 48 as an incident beam was used. But the targets were prepared in the research reactors. So the targets speak about curium, americium, plutonium, bicarrelium. Here all of them actually were based on some actinides irradiated in high flux reactors either in Russian Federation or in Oak Ridge to create these targets. And later on to create these reactions to create tens of atoms which allows you to claim that these super heavy elements are created and they do exist for a while. Let's come back to the nuclear power. This is where nuclear power stands today. We are somewhere between generation 3 generation 3 plus. And going from generation 3 to generation plus we say we are going to the evolutionary design. What does mean evolutionary means not a really big change. So you are still on the same technology. You try to grab the remaining tens of percent in efficiency, maybe 10 or 15 percent more in burn up of the fuel. You improve of course the safety as a major aspect of these concepts, but the principle remains the same. You are still speaking about thermal neutrons, thermal neutron based nuclear power. So where is generation 4 comes, and I explain to you, I will come back to the issue which is the main issue going to generation 4. And that's why these designs are called the revolutionary designs because there is a completely new approach. You most probably will not need enriched fuel because by charging natural uranium this will be self-generating facilities and most of them have a concept of running on fast neutrons rather than on thermal neutrons. But I come back to the photo or picture what I showed you. If you want to go there you need to make sure where you place the fuel, where you get your heat extracted. How you moderate your neutrons. How do you operate this critical reactor? You will need new materials and new fuels. And again it's presently not available and not proven technology in terms of damage rates you expect. Even the fusion reactors there you see completely outside of the known zone today. And in terms of temperature, you want to go to higher temperature, you want to get materials with a better resistance to the irradiations. This is here what we're talking about. And what I'm saying is that only research reactors are not able to answer these questions today. Why? Because we need fast neutrons. When you go to fusion you even need much faster neutrons. We're talking about 14 MEV neutrons where no research reactor or unless you use specific accelerator can produce. For example for 14 MEV neutrons the concept here is to shoot neutrons on lithium target and create something representative to the fusion first blanket area where you are aiming at 14 MEV neutrons as a result of DT reaction. Because if you look at the green line this is typical research reactor spectrum peaked at the fission energy. Now if you go to the ether which is first fusion experiment is really peaked at 14 MEV here. And if this particular accelerator would actually result on average to this particular energy region. So you need a dedicated irradiation facility to test future materials for the future power plants. Now this facility doesn't exist and to make it run at the intensities which are required it will take another 10 or 15 years. So that's something what one needs to keep in mind. Now research reactors alone can create these DPA levels. It depends on a thermal power of the reactor and for how long you can irradiate. So you will have these damage rates after 3, 4, 5 years of irradiation. The problem is that the spectrum is different. You will have DPA, sufficient DPAs here but you will not have sufficient gas production which is required for 14 MEV neutrons. You will not create enough hydrogen or helium which are required realistic conditions for the future fusion reactor. So what is the way out? Typically you would irradiate materials in the reactor to obtain sufficient DPAs and you will implant hydrogen and helium using accelerators to create these gases inside the materials. This is again an example of how research reactor and accelerators can be used together for the one objective. Now this is a bit different story. You want to create hydrogen, helium and induce DPAs at the same time. This is a realistic situation. In this example you will create them separately. Are we in the same conditions? So you need also some modeling at the atomic level to try to understand and link that from experimental facility conditions to the realistic conditions. So I hope I at least gave you some taste what research reactors can do in addition to nuclear data measurements. And the message here is that well we estimate that in next 10-15 years we will not have 247 research reactors operational anymore. One of the reasons that these facilities are very old. Another reason is that they become more and more expensive. And the third reason is that we are using them more efficiently. So we can do more with less facilities available. So I think in next 10-15 years we will have maybe another three-fourth palatial neutron sources. But we will not increase number of research reactors. It's even opposite. We will have maybe 150, 170 research reactors operational worldwide. So thank you for your attention and I hope I can take another couple of questions.