WEBVTT 1 00:00:00.359 --> 00:00:00.719 jopolito: Overall. 2 00:00:24.750 --> 00:00:38.670 jopolito: Alright, so let's get started, everyone today it's my great pleasure to introduce a professor from the University of California San Diego will be speaking to us about all the great of plasma plasma research they're doing their lab. 3 00:00:40.020 --> 00:00:48.120 jopolito: Professor bag is a professor of engineering physics at the Department of mechanical engineering and aerospace engineering at the University of California San Diego. 4 00:00:48.930 --> 00:00:58.800 jopolito: He received his PhD from imperial college London where his expertise is in the field of laser plasma interaction pulse power driven X punches and Z pinches and new trend sources. 5 00:00:59.370 --> 00:01:10.950 jopolito: he's published over 250 peer reviewed journal articles, including articles in nature nature physics nature photonics and physical review letters with citations exceeding 9000 and an H index of 50. 6 00:01:12.420 --> 00:01:18.780 jopolito: he's a fellow of the American physical society, as well as the I Tripoli and the American Association for the advancement of science. 7 00:01:19.440 --> 00:01:35.400 jopolito: has been a winner of the departments department of junior faculty award and the ieee early career award this year, in fact, he received I Tripoli plasma science and applications award and he served as the Chair of the high energy density science association or otherwise known as headset. 8 00:01:36.450 --> 00:01:44.760 jopolito: It to two different terms, most recently in 2017 and 2019 he's also served as the NIF the national ignition facility and the Jupiter user group. 9 00:01:46.380 --> 00:01:46.770 jopolito: chair. 10 00:01:48.570 --> 00:01:52.560 jopolito: i'll just want to mention i've had a great great privilege of working with Professor bag on. 11 00:01:53.130 --> 00:02:00.630 jopolito: The new xena us consortium that Professor bag started up on his own initiative and basically it's just a. 12 00:02:01.170 --> 00:02:09.090 jopolito: Network trying to bring together all the pulse power machines spread out all over the country together in a collaborative network and building some user facilities and some. 13 00:02:09.570 --> 00:02:17.910 jopolito: great opportunities so effect we're planning a workshop right now that'll be next month, so the second xena us workshop. 14 00:02:19.710 --> 00:02:28.500 jopolito: So i've just really enjoyed his visit today and talking to him about the pinch physics i'm really looking forward to hearing his talk today, but before that we have one very important. 15 00:02:29.760 --> 00:02:35.100 jopolito: Business matter to attend to, and that is the presentation of the mitzi Cup, the famous mitzi Cup. 16 00:02:36.180 --> 00:02:36.690 jopolito: So. 17 00:02:39.000 --> 00:02:45.060 jopolito: that's her bed come on up here and I guess you can hold that and shake your hand. 18 00:02:53.010 --> 00:02:58.020 jopolito: Okay, thank you yeah Thank you so let you take it away from here looks like. 19 00:02:59.190 --> 00:02:59.310 Oh. 20 00:03:14.130 --> 00:03:17.880 jopolito: hey Thank you so much for your kind introduction I appreciate it. 21 00:03:19.980 --> 00:03:31.740 jopolito: So today my focus is going to be on the bench research that we do at ucsd so before I start i'd like to see how many of you know about the thinking. 22 00:03:33.930 --> 00:03:35.220 jopolito: Okay, good number. 23 00:03:36.360 --> 00:03:42.720 jopolito: And I like to keep this talk very informal so you can stop me at any time during the talk. 24 00:03:44.040 --> 00:03:48.720 jopolito: there's no guarantee that I will answer your question but hey i'm tenured Professor. 25 00:03:52.320 --> 00:03:53.040 jopolito: Okay. 26 00:03:59.640 --> 00:04:01.740 jopolito: Let me first introduce my group. 27 00:04:03.630 --> 00:04:04.380 jopolito: So. 28 00:04:05.670 --> 00:04:16.920 jopolito: Our next slide i'm going to show you what research area I work on, but I have for research scientists to postdocs in my group blow in. 29 00:04:18.150 --> 00:04:25.200 jopolito: The blue tag those are research scientists and to post on, and then I have. 30 00:04:26.340 --> 00:04:28.680 jopolito: 10 graduate student. 31 00:04:29.850 --> 00:04:39.780 jopolito: This picture is all some of these students have graduated and I have three masters students who are doing master's thesis in my lab. 32 00:04:42.000 --> 00:04:44.460 jopolito: I work on a variety of areas. 33 00:04:46.020 --> 00:04:58.950 jopolito: i'm master of all trades what is called a jack of all trades, but master of none so here, you see, I work on high intensity laser mentoring direction. 34 00:05:00.330 --> 00:05:17.820 jopolito: We whether it's a long pause and short pause when we are talking about the long pause we work on laser plasma instabilities and understanding of laser plasma instabilities is extremely important for initial confinement few yen and. 35 00:05:19.350 --> 00:05:24.750 jopolito: And to find out what are the mitigation techniques for those instabilities. 36 00:05:26.790 --> 00:05:37.200 jopolito: We also work on relativistic electron as transport that's relevant to fast ignition of initial confinement fusion you're going to hear word. 37 00:05:37.770 --> 00:05:59.220 jopolito: Initial confinement fusion, because they said very exciting time if you're working in high energy density physics, because of 1.3 mega joules of year again on national ignition facility so you know national ignition facility is to mega do this term, so is 0.7 gain so. 38 00:06:00.240 --> 00:06:17.730 jopolito: That that that is extremely exciting exciting time one thing we also studies one dense matter how to create one does matter we use proton beans produced from days of plasma interaction to create bonbons matter. 39 00:06:18.780 --> 00:06:35.550 jopolito: This is something one does matter is between condensed matter and and the plasma we talk about, and there are many exciting properties of this matter and some of my colleagues here working on one dense matter. 40 00:06:37.980 --> 00:06:47.880 jopolito: We have a variety of modeling code that we use for our laser plasma work he Paul gillespie because Zuma, and so forth. 41 00:06:50.340 --> 00:07:11.940 jopolito: We also work on shark ignition concept of ice at length and our focus on the pitches is stage see paying for fuel again and i'm going to talk about that later on, we also use the plasma flows to create a cleaner sharks. 42 00:07:12.990 --> 00:07:21.060 jopolito: that's again using to wider is to create the flow then collide those flow. 43 00:07:22.740 --> 00:07:39.360 jopolito: And then we have X pinch work where we came up with a new idea, so you know in exponent is the wiser us and when this wise cross at the Cross point you form a bride. 44 00:07:40.710 --> 00:07:49.320 jopolito: localized accurate source what we did we took a file and we are next door to general atomics be used their high power laser to cut the. 45 00:07:49.800 --> 00:07:59.940 jopolito: file in shape effects and the beauty of that is that you can add the boys, in the shape you want, and one of my students who recently graduated. 46 00:08:00.570 --> 00:08:07.080 jopolito: wrote an article on that i'm not going to talk about X pinches today, but if you are interested in X pinches. 47 00:08:07.530 --> 00:08:18.180 jopolito: i'll be happy to share the paper so in his thesis what he did on one particular machine he made a comparison of why the expenses with hybrid expenses. 48 00:08:18.720 --> 00:08:36.990 jopolito: And laser cut expenses and he found out which one is better, there are pros and cons for each of and the final thing is dance plasma focus that's that's another device in the family of safe in case I believe I can take my last count right. 49 00:08:39.660 --> 00:08:49.620 jopolito: So i'm going to show some of the dance plasma focus experiment what I don't have on this list is a new project we started. 50 00:08:50.700 --> 00:08:57.150 jopolito: funded by deidre is Defense threat Protection Agency, and what we are doing is. 51 00:08:58.320 --> 00:09:10.440 jopolito: experiments and simulation on direct laser impulse, so we are studying how the plasma is updated, as you shine the laser on the material and determine mechanical shark generation. 52 00:09:13.140 --> 00:09:13.560 jopolito: We. 53 00:09:15.480 --> 00:09:16.320 jopolito: publish. 54 00:09:17.550 --> 00:09:28.380 jopolito: On average 12 papers, a year more, you will see in most of our papers are Grad students are for starters, though the paper you see the students. 55 00:09:29.460 --> 00:09:31.230 jopolito: is a part of their faces work. 56 00:09:34.530 --> 00:09:44.820 jopolito: And we are leading an nsf Center of excellence on matter under extreme condition and in that Center we have three trust areas. 57 00:09:52.170 --> 00:09:56.130 jopolito: First failure, one is energy transport in high energy density system. 58 00:09:57.810 --> 00:10:09.060 jopolito: Trust to his material proper is a process ED regime and then this is the fundamental research and both of these areas have applications in. 59 00:10:09.660 --> 00:10:20.970 jopolito: planetary science and astrophysical astrophysics so we use this knowledge to apply to understand astrophysical plasmas and planets. 60 00:10:21.420 --> 00:10:43.950 jopolito: And you can see that they are synergies in both research areas we create shots in both conductivity or resist activity version of stage we use radiation play an important role and also common team is magnetic field either generation or apply magnetic fields and also the. 61 00:10:45.150 --> 00:10:47.460 jopolito: generation of energetic particles. 62 00:10:51.390 --> 00:11:09.660 jopolito: Okay, what is the think most of you know what is a pinch, it is one of the simplest magnetic confinement devices, so what you have is two electrodes you pass the current through the gas in this case gas, you can have while there as well. 63 00:11:10.770 --> 00:11:21.840 jopolito: And when you pass the current you generate a magnetic field what we call self generated magnetic field, so you have a cross be force which pinches the gas. 64 00:11:23.790 --> 00:11:37.560 jopolito: To the axes, so you achieve higher density and high temperature, so what we want to know for any pinch, whether it's y Z paint your liners a paint your gas. 65 00:11:38.430 --> 00:11:50.520 jopolito: tank you want to know what is the pinch radius do you want to know what is the peak density and what is the current distribution and current district, knowing the current distribution is extremely challenging problems. 66 00:11:51.480 --> 00:12:08.370 jopolito: So it is very hard to know the current distribution because typical Saturday rotation is very difficult, because it works laser penetrates after critical densely plasma it doesn't penetrate through dance plasma. 67 00:12:09.600 --> 00:12:16.470 jopolito: They are other techniques like proton probing if you have a high power laser or short pass laser you can do proton. 68 00:12:17.280 --> 00:12:27.540 jopolito: probing we have used semen spectroscopy to get the information of the current distribution but i'm not going to talk about that so. 69 00:12:28.530 --> 00:12:38.850 jopolito: This property that i'm talking here, why these properties are important, the reason, these properties are important that this can influence the potential applications. 70 00:12:39.240 --> 00:12:48.210 jopolito: And one of the application is thermonuclear fusion, for which you want to have stable plasma right. 71 00:12:49.080 --> 00:13:01.110 jopolito: And then they are certain parameters that you can control, for example, the current flowing in the plasma, you can control right because you can build a device to give you one more game current. 72 00:13:02.280 --> 00:13:18.150 jopolito: But what you cannot control how much current is flowing in the load, so you need to condition the load and the line density, which is given here, meaning, you can control what is the pressure of the gas and if you're using the wire. 73 00:13:19.350 --> 00:13:25.140 jopolito: The density of aluminium is different than the density of tungsten so you can use appropriate tamika. 74 00:13:28.950 --> 00:13:38.340 jopolito: So I took this slide from my cooney or Sandia national labs to show you what kind of conditions, the pinch can create. 75 00:13:39.420 --> 00:13:45.750 jopolito: And I said that I work in the area of high energy density physics and the holy grail of high energy density physics, is that. 76 00:13:47.220 --> 00:14:04.500 jopolito: A pressure of one megabyte or above on on the matter so let's see if we have, and you can convert that pressure into two but let's see if you have one mega joules of energy and kinetic energy of F 150. 77 00:14:05.550 --> 00:14:21.780 jopolito: truck at 60 miles per hour if he chased the wall that's that's what happened so it's a significant amount of energy and, if you want to compare with a few other things, it is point four, eight times energy in a stick of dynamite. 78 00:14:23.130 --> 00:14:35.910 jopolito: And hundred Watt light bulb uses one mega June in about three hours so and the plasma we deal with the collapse, with the velocity of. 79 00:14:36.630 --> 00:14:49.290 jopolito: Hundreds of kilometers per second in this case I have 500 kilometers per second and if you have that kind of velocity, then you can go from New York to La in eight seconds. 80 00:14:50.340 --> 00:14:53.490 jopolito: Right I believe Elon musk is working on this idea. 81 00:14:54.750 --> 00:15:01.710 jopolito: So, so I just wanted to give you a flavor of what what kind of energies we deal with. 82 00:15:03.390 --> 00:15:04.650 jopolito: With the punches. 83 00:15:07.290 --> 00:15:08.340 jopolito: Any questions so far. 84 00:15:11.280 --> 00:15:20.340 jopolito: Okay let's move on, let me give you a historical perspective first known see pink experiment was. 85 00:15:21.870 --> 00:15:28.680 jopolito: done way back in 1790 it wasn't called the page experiment at that time. 86 00:15:29.970 --> 00:15:30.900 jopolito: And that was. 87 00:15:32.070 --> 00:15:42.960 jopolito: Martinez one Martin in Amsterdam in 1790 So you see the jars of capacitors and the current pass through the wire and the wire. 88 00:15:43.650 --> 00:15:57.450 jopolito: exploded I don't know what kind of Defense industry was there in in 1790 so the capacitor energy was one kilo do, and they were hundred lead and George discharged into a long one millimeter. 89 00:15:57.960 --> 00:16:24.060 jopolito: Wide shown somewhere on this slide in La in late 1940s Thompson and blackman at imperial college they came idea of linear Congressional painful compression of plasma and they submitted it and a copy of patent is shown here that was be used that linear to for producing fusion. 90 00:16:29.610 --> 00:16:30.630 jopolito: There, at least. 91 00:16:32.220 --> 00:16:44.010 jopolito: doesn't type of see pinches compression of page gas path i'm not going to talk about every time I give you a few examples here, why expense. 92 00:16:44.790 --> 00:17:06.810 jopolito: expense, you see here, this is the winery seeping can, this is the dense plasma focus today my focus is going to be on gas pudsey pitches and dance plasma focus at some point, some of these ideas have been used for thermo nuclear fusion, but the issues have been. 93 00:17:08.010 --> 00:17:15.840 jopolito: instabilities whether it's an equal to not instability and equal to one instability or a magneto related or instability. 94 00:17:22.290 --> 00:17:25.440 jopolito: As I said that zip engines have long history. 95 00:17:26.610 --> 00:17:33.030 jopolito: And here i'm talking about from 1950s onwards so dense plasma focus research. 96 00:17:34.920 --> 00:17:47.370 jopolito: was done in 1950 actually there was a gentleman called matter she came up with a device called dense plasma focus and in former Soviet Union, there was. 97 00:17:49.110 --> 00:17:53.220 jopolito: There was another gentleman who came up with the same idea but. 98 00:17:54.240 --> 00:18:05.070 jopolito: Different design, but the working principles for both dense plasma focus was the same the electrode configuration was different so initially. 99 00:18:05.760 --> 00:18:23.760 jopolito: It was taught that then the neutron that are coming out from dense plasma focus or of thermonuclear or region, so there was plenty of excitement that this device can be used for thermo nuclear fusion, but later on, it was found that those neutrons are due to being target. 100 00:18:25.740 --> 00:18:45.480 jopolito: Then I mentioned linear deuterium see pinches that's basically you have a gas field in the tube between the electrode and you pass the current and you change the plasma too high density and temperature and in 1990s fiber pitch was very popular. 101 00:18:46.890 --> 00:19:02.340 jopolito: The reason for fiber pinch was that in linear finches you start with the gas right so densities blow and you are doing work on that gas to compress it to the smaller diameter and to higher density. 102 00:19:02.760 --> 00:19:19.890 jopolito: So the idea was why can't we use the wires Why is a solid density right, so you don't have to spend energy in compressing the guests to high density that's why fiber see pinches what us, and that was also very. 103 00:19:21.780 --> 00:19:31.470 jopolito: There was excitement about fibers he pinches because, again, you produce the neutron and pinch was initially stable. 104 00:19:32.550 --> 00:19:40.260 jopolito: And and at nrl and at Los Alamos national lab cryogenic fibers were used. 105 00:19:41.280 --> 00:19:41.910 jopolito: and 106 00:19:44.010 --> 00:19:45.900 jopolito: In this time frame the. 107 00:19:47.730 --> 00:19:59.430 jopolito: The dp devices, they had a long current policies of the order of microseconds and long current policies are not good, because if you are developing. 108 00:20:00.120 --> 00:20:08.100 jopolito: instability, then this instability is we'll have plenty of time to grow, so the idea was that to have. 109 00:20:09.000 --> 00:20:27.330 jopolito: Short current policies and Charlie Martin at atomic weapon establishment at a w E he came up with the idea of horsepower devices marks bank has power devices, we have you have much bang, you have performing line so a transfer line and then your load. 110 00:20:28.560 --> 00:20:38.760 jopolito: And you can compress the pulse 200 nanoseconds is very similar to what we call about chip pass amplification in laser research. 111 00:20:40.200 --> 00:20:56.820 jopolito: And that revolutionized the seepage work and then the horsepower driven sub kV radiation so says for radiation physics application and in mid 1990s of before I go to mid 1990s actually. 112 00:20:57.480 --> 00:21:12.660 jopolito: GASP of experiments initial GASP of experiments were done in 1972 at uc Irvine Professor Norman rough talker he and his group came up with the idea of using gas power. 113 00:21:14.910 --> 00:21:26.700 jopolito: So I already told you dd fibers then in mid 90s Sandia national lab carried out experiments with why. 114 00:21:27.810 --> 00:21:29.100 jopolito: arrays a pinches. 115 00:21:30.150 --> 00:21:40.260 jopolito: Some experiments were done at the company called physics international where they were producing radiation sources and they use very small number of wives. 116 00:21:40.770 --> 00:21:51.510 jopolito: And they saw that when you increase the wire X Ray post goes up so sandy experiment, I believe, Professor mcbride was involved in those experiment that you use 300. 117 00:21:52.140 --> 00:22:09.900 jopolito: Plus wise constant wise and you create significant amount of radiation, I believe the record is 2.8 mega mega you so you can use 2.8 mega joules X rays to Dr target I see if target so. 118 00:22:11.520 --> 00:22:12.630 jopolito: Those experiments. 119 00:22:13.650 --> 00:22:14.310 jopolito: Go got. 120 00:22:18.180 --> 00:22:31.590 jopolito: Plenty of publicity and I don't know how i'm doing in time, but this is one interesting story, and please tell me if I say inaccurate there so. 121 00:22:32.790 --> 00:22:51.900 jopolito: When two mega joules X rays were reported, it was on CNN and it was also in other media that time social media was not used that much so, someone from Hollywood called my colleagues at sandy and said, all you have generated these X rays, can you. 122 00:22:53.400 --> 00:23:06.150 jopolito: generate electromagnetic radiation and they said yes, you can generate an electromagnetic radiation and they are all can these electromagnetic radiation used to knock down the power plant and they said yes, technically, you can. 123 00:23:06.840 --> 00:23:24.180 jopolito: And next question was can you put this machine on the back of the when of course we've been you cannot put on the machine, you cannot put but they ran with the idea, and they made ocean's 11 movie So if you have watched that movie finch machine is actually came from that side. 124 00:23:26.130 --> 00:23:39.060 jopolito: Okay, so I have given you history of zipping cheese, and now we are in the regime, we are, we are working on magneto inertial fusion so is a combination of magnetic field and. 125 00:23:39.780 --> 00:23:52.170 jopolito: inertial fusion megalith concept, you must have her pursued at Sandia national lab and is what going on on my MAC live to understand basic science. 126 00:23:55.230 --> 00:24:01.680 jopolito: Okay, let me change gears here So here we have. 127 00:24:03.330 --> 00:24:15.780 jopolito: skates and forced balance, so this is equation of motion, so we have the pressure due to the S, and we have a cross before, and if you simplify this equation. 128 00:24:16.710 --> 00:24:29.670 jopolito: Then what you get here is that because it's a Columbia, then you have gradient of P equal to jb they are opposing forces and if we use the assumption that. 129 00:24:31.770 --> 00:24:50.130 jopolito: So let's see quantities very here with our as you see, we are compressing in the radial direction and we assume that the pain is infinitely long, so we can ignore any energy loss to the electrodes. 130 00:24:52.290 --> 00:25:03.510 jopolito: And if we simplify that equation, and again i'm not going to go into the detail what you get is what we call Bennett equation, which is the relationship of the current. 131 00:25:04.080 --> 00:25:16.920 jopolito: With the temperature and the line density here, so you can, if you put the numbers here for the current density of tend to the team what 18 permitted Q. 132 00:25:18.450 --> 00:25:32.010 jopolito: R squared I think is by unit Lang and, if you take the current of one mega and then what you can do is you get the temperature of can kV so with one mega am. 133 00:25:33.180 --> 00:25:41.790 jopolito: And with the line density of for 10 to the 18 you get 10 kV why this 10 K, is important. 134 00:25:46.470 --> 00:25:51.600 jopolito: You should, if you look at the Cross section nuclear cross section for dd. 135 00:25:53.430 --> 00:26:14.340 jopolito: dd those are the important one, when you have 10 K we temperature than you can overcome nuclear forces and and you can choose this like nuclear to produce fusion, so that that's exciting that you can use one man gang pattern to reach 10 kV temperature. 136 00:26:15.570 --> 00:26:17.280 jopolito: To produce thermonuclear fusion. 137 00:26:18.600 --> 00:26:20.010 jopolito: there's a caveat there. 138 00:26:21.870 --> 00:26:22.980 jopolito: What is the issue here. 139 00:26:27.210 --> 00:26:40.260 jopolito: Thank you instabilities So if you have instabilities you cannot confine the plasma long enough and it disrupts so that is one of the fundamental issues so. 140 00:26:42.030 --> 00:26:47.400 jopolito: So my mentor at imperial college Professor haines she. 141 00:26:48.630 --> 00:27:00.840 jopolito: This is if you're doing deep into research, this is interesting paper to read, so he showed that seepage can satisfy Lawson criteria Lawson criteria is the product of. 142 00:27:01.350 --> 00:27:14.520 jopolito: Our dance fee and the confinement times so is 510 to the 22nd per meter tube and if you in this case he assume the temperature of 25 kV so. 143 00:27:15.750 --> 00:27:23.130 jopolito: This assumption was that the confinement, time is determined by law says to the electrodes which are already mentioned and pinches in radio. 144 00:27:23.700 --> 00:27:34.320 jopolito: equilibrium, so if you have a time scale of 100 nanoseconds you would need about, as I said, one Meg and current, this is the length of the page. 145 00:27:35.010 --> 00:27:55.650 jopolito: This is the density the takeaway messages, if you have solid fiber then with one megan current you can achieve this criteria, however, the biggest can condition here is there, your finch has to be stable for many. 146 00:27:57.180 --> 00:27:57.420 jopolito: As. 147 00:27:59.220 --> 00:27:59.760 jopolito: A time. 148 00:28:00.780 --> 00:28:02.520 jopolito: distributed growth times right. 149 00:28:04.110 --> 00:28:15.060 jopolito: And this was the idea on which MAC by was very if you're working on the punches, then you know what magpie is is a passport machine at imperial college. 150 00:28:21.000 --> 00:28:35.130 jopolito: So peace and Brzezinski again peace in the UK and Reagan steen former Soviet Union, they came up with the current here called peace pregame skate current you see the relationship here, according to that. 151 00:28:36.510 --> 00:28:53.340 jopolito: If you put the numbers here, then you will see that you would need a one man gang current again to achieve the condition that I was talking about, and if you neglect conduction losses than a the radius here so a.if it's. 152 00:28:54.450 --> 00:29:12.570 jopolito: If I is less than piece Brzezinski current than the pinch expand, but if it's more than peace against the current and, in this case peace roginsky current for hydrogen is one mega So if you have one more game, or more than one mag and current then your pinch. 153 00:29:13.890 --> 00:29:22.110 jopolito: Or the plasma will contract or the access so horsepower made it possible to test this. 154 00:29:23.130 --> 00:29:29.190 jopolito: theories again i'm not going to go to those experiments i'll be happy to. 155 00:29:30.480 --> 00:29:36.630 jopolito: Share papers with you, but I want to go into gas paint experiments, we have done. 156 00:29:38.100 --> 00:29:43.530 jopolito: So the idea that we've been pursuing is called stage Z pinch. 157 00:29:45.720 --> 00:30:01.320 jopolito: So, how does it work, what you have here this schematic show this is a liner it could be a metal or it could be gas, and then you have a target here, which is deuterium so you pass the current through the liner. 158 00:30:02.430 --> 00:30:10.620 jopolito: The current produces magnetic field with the fuses through this liner produces the shot, which she is. 159 00:30:12.180 --> 00:30:24.240 jopolito: she's the plasma here, and when the liner claps on the target, then you generate you do the work, and you are generating high temperature and density, so it relies on. 160 00:30:24.780 --> 00:30:41.400 jopolito: snowplow shock the cheating preheating you are getting is through the shock compared to in mag live, where you use the laser to create the create the target as I carried out, as I mentioned previously, that. 161 00:30:43.500 --> 00:30:50.460 jopolito: GASP of idea was conceived at uc Irvine so initial experiments were done. 162 00:30:51.360 --> 00:31:01.080 jopolito: At uc Irvine and here you can see from the dead experiment that's the liner which is becoming unstable, but the target is stable so. 163 00:31:01.410 --> 00:31:12.570 jopolito: The liner is detached from the target so later in time it's becoming unstable, it is not going to affect your target and that's that's the cool thing about this concept. 164 00:31:16.590 --> 00:31:23.220 jopolito: Again, you don't want to have magneto relative instability, so you need to mitigate the effects of. 165 00:31:24.600 --> 00:31:25.470 jopolito: magneto. 166 00:31:26.850 --> 00:31:39.840 jopolito: Relatively instabilities, how can you mitigate relative or instabilities experiments and simulations have been done on ideas like you can apply external magnetic field Axial magnetic fields. 167 00:31:40.500 --> 00:31:54.300 jopolito: And when you remember you have Axial magnetic field and then these are self generated azimuth and magnetic fields, so you have kind of a flux compression right, so the tension in the magnetic lines is. 168 00:31:54.960 --> 00:32:06.930 jopolito: Making the plasma uniform, or in other words, reducing the amplitude of instability that's one way of doing that the second way of doing is you have. 169 00:32:08.190 --> 00:32:09.240 jopolito: killer density. 170 00:32:10.620 --> 00:32:20.160 jopolito: profile, how can you tailor the density profile the way you can tailor the density profile is that he used multiple shelves right. 171 00:32:21.600 --> 00:32:26.310 jopolito: And if you remember wider is how many of you know about nested wineries. 172 00:32:29.220 --> 00:32:43.770 jopolito: So in nested wineries, if you remember, they were to wider is outer winery would implode on Nina wider array and that gave much better results than the single winery, and the reason for that was that. 173 00:32:44.460 --> 00:32:55.200 jopolito: When outer winery in florist on the inner winery it decelerates right so really dealer instability is on the acceleration. 174 00:32:55.920 --> 00:33:04.890 jopolito: So if you are producing the acceleration, then you are the growth of instability, going to be reduced similar idea here that you use Taylor. 175 00:33:05.430 --> 00:33:16.770 jopolito: density profile or multi Shell, so we carried out our first experiment at university of Nevada Reno with one mega machine, you can. 176 00:33:17.520 --> 00:33:28.740 jopolito: See the parameters of the machine we use krypton hollow liner and we use details from yes target as you see, in schematic here. 177 00:33:29.580 --> 00:33:40.590 jopolito: And what we also did in order to understand what is the critical value of magnetic fields that will mitigate magneto relative or instability, so we buried. 178 00:33:41.280 --> 00:33:54.120 jopolito: The external magnetic fields, from zero to three logos I will be using word like Axial magnetic field or external magnetic field is the same thing, so please don't get confused any questions so far. 179 00:33:58.410 --> 00:33:58.680 Okay. 180 00:34:02.580 --> 00:34:06.600 jopolito: So these are some of the images. 181 00:34:09.510 --> 00:34:18.480 jopolito: are taken I think these are actually images here, you see, we are changing the magnetic field, this is near the peak of the current. 182 00:34:18.990 --> 00:34:40.260 jopolito: And you can see that, when we have magnetic field about point one tesla or more in this case point one five Kessler pinches looks more stable than without magnetic field and i'm going to show you a few more example and since then they have been other experiments as well, so. 183 00:34:42.510 --> 00:34:45.000 jopolito: This is the demonstration that the magnetic field. 184 00:34:46.260 --> 00:34:56.220 jopolito: have to mitigate magneto retailer instability and this is from Fabio counties paper what you see here. 185 00:34:56.820 --> 00:35:15.390 jopolito: plasma water radius as a function of time and the steam instability amplitude again for different values of magnetic fields, so you can see that, when we apply external magnetic fields, the amplitude of the instability is reduce. 186 00:35:25.200 --> 00:35:30.480 jopolito: Okay, so those experiments were done on conventional marks bank system. 187 00:35:31.650 --> 00:35:38.670 jopolito: And the first farming line nowadays new technology called linear transformer driver. 188 00:35:39.150 --> 00:35:49.770 jopolito: I don't need to tell you about linear transform or driver, one of the best papers is written by Professor mcbride actually one it please best paper award as well. 189 00:35:50.610 --> 00:35:58.080 jopolito: So if you are working in this field, and if you want to know about linear transform driver that's that's the paper you need to read. 190 00:35:58.920 --> 00:36:22.410 jopolito: that's, the first thing I asked my students students, so the beauty of linear transformer driver is that is a very compact system, the one you have here is three millimeter three meters in diameter, the one I have at us ucsd two meter in diameter and you can take plenty of shots. 191 00:36:23.550 --> 00:36:24.120 jopolito: In a day. 192 00:36:25.200 --> 00:36:26.460 jopolito: On these devices. 193 00:36:28.410 --> 00:36:46.470 jopolito: And I will tell you why it is useful for another thing, and he is the trailer of what i'm going to show you in the next few slides So if you pay attention here, you can see that this is. 194 00:36:47.940 --> 00:36:54.480 jopolito: You and our marks bank machine which is 130 colored you. 195 00:36:55.830 --> 00:36:57.480 jopolito: In energy in the capacitor bank. 196 00:36:58.770 --> 00:37:07.620 jopolito: Current is one mega ampere and the rice, time is hundred nanoseconds and what you see here is the. 197 00:37:08.790 --> 00:37:29.010 jopolito: radius the plasma, in this case casper is painting and around the current maximum and the energy that is going into the change is held the order of one killer tool from 130 kilo June to one kilo you. 198 00:37:29.760 --> 00:37:50.670 jopolito: So what we have is about point 8% energy couple to the load right look at our Ltd, if you have truckload you that's significantly smaller here current about the same about point eight meghan rice, time is not too different. 199 00:37:52.170 --> 00:38:07.470 jopolito: You are coupling to the Lord same amount of energy, so you can see that the energy coupled to the Lord in a TD devices is an order of magnitude higher. 200 00:38:09.240 --> 00:38:18.210 jopolito: So that's that is very encouraging that you can use this compact system for efficient energy coupling to the Lord. 201 00:38:18.840 --> 00:38:30.540 jopolito: And the Lord i'm talking about is the gas pump gas pumps are like diameter, so they have low impedance these are low impedance devices, so you can come couple the energy more efficiently. 202 00:38:31.590 --> 00:38:34.710 jopolito: Maybe issue if you are using wise single wives. 203 00:38:36.030 --> 00:38:36.450 jopolito: Okay. 204 00:38:41.520 --> 00:38:42.540 jopolito: This is the. 205 00:38:43.620 --> 00:38:47.190 jopolito: Solid wants design of the machines. 206 00:38:48.420 --> 00:38:51.930 jopolito: This is the current web form here. 207 00:38:53.220 --> 00:39:02.280 jopolito: This is our injector very similar to what you have in your lab again i'm not going to go through everything so did. 208 00:39:02.820 --> 00:39:14.190 jopolito: The gas pump is coming from the top, these are the electrodes and then again current is flowing in the direction that's why called the page and then you have mental magnetic field. 209 00:39:17.220 --> 00:39:19.860 jopolito: I will talk about the diagnostics, we have. 210 00:39:21.420 --> 00:39:23.940 jopolito: This is the experimental data so. 211 00:39:25.740 --> 00:39:26.640 jopolito: This is the. 212 00:39:28.200 --> 00:39:28.890 jopolito: implosion. 213 00:39:30.180 --> 00:39:40.620 jopolito: Of the gas path from modeling from zero D model from Hydra and from experiments it matches very well. 214 00:39:43.920 --> 00:39:53.700 jopolito: So we are getting velocities of all the order of 200 kilometers per second we can use these philosophies to calculate the kinetic energy. 215 00:39:55.590 --> 00:40:07.320 jopolito: To see how much energy is couple to the to the target and also you see a small dip in the current that we use. 216 00:40:09.150 --> 00:40:09.960 jopolito: As a. 217 00:40:11.550 --> 00:40:19.170 jopolito: What is the right word we use as indication that the efficient energies couple to the target if you see the tape in the car. 218 00:40:27.060 --> 00:40:37.170 jopolito: So we carried out experiments with organ and neon gas what you see on the left hand side is. 219 00:40:39.000 --> 00:40:53.550 jopolito: Actually images at different times zero nanosecond means is had the peak of the current right, so you can see that the gas pump current starts to flow through the gas pump and. 220 00:40:54.270 --> 00:41:09.270 jopolito: Earlier on, it becomes unstable and you see when it pinches to the access is pretty unstable and these are the X Ray policies which are of two to five nanosecond duration and you see X Ray year we got from the pain diodes. 221 00:41:11.670 --> 00:41:12.630 jopolito: And for neon. 222 00:41:15.270 --> 00:41:26.340 jopolito: The behavior is significantly different, the pinch is not more uniform compared to Oregon and look at the X Ray policies they are lot more. 223 00:41:27.570 --> 00:41:38.880 jopolito: Longer compared to organ exchanges, so why this is happening again, we have some ideas but there's no concrete conclusion here. 224 00:41:39.300 --> 00:41:52.740 jopolito: One thing is that maybe density profiles are different into cases The other thing is that this activities or organ and neon are different, and they are playing a role here, in the current. 225 00:41:54.180 --> 00:41:57.870 jopolito: and other differences that organ is lot more. 226 00:41:59.970 --> 00:42:13.080 jopolito: radiative because it's relatively high is immaterial he is a cane compared to me on which is these 10 right, so the experiments on dense plasma focus have been done that show that. 227 00:42:14.100 --> 00:42:28.980 jopolito: If you are below the 18 you're financially stable because radiation or not playing important role, however, if you're seeing increases, then you start to see instabilities and radiative claps, if you like. 228 00:42:29.880 --> 00:42:36.330 jopolito: And, and that is giving rise to the instabilities form, but we are investigating this more. 229 00:42:37.830 --> 00:42:55.260 jopolito: As I said that energy coupling here, you see the comparison, the there are two ways we can get the kinetic energy of the page we use both experiments and we use modeling hydro modeling to get the information about the kinetic energy and you can also. 230 00:42:56.580 --> 00:43:01.200 jopolito: The kinetic energy of your gas pump is converted into thermal energy and that. 231 00:43:02.730 --> 00:43:09.660 jopolito: comes out of the page as a form of X rays, so if you're using pain diode, then you can see what kind of. 232 00:43:10.740 --> 00:43:19.200 jopolito: Energy is coming out from the pain so here is the comparison between two devices that I showed earlier on, and you can see that. 233 00:43:20.520 --> 00:43:33.870 jopolito: kinetic energy in case of Seabra was 2.8 load you because the initial energy was higher and, in this case, point six five colored you and you can see, as I said previously that day is a. 234 00:43:34.980 --> 00:43:36.210 jopolito: factor of 10. 235 00:43:38.130 --> 00:43:44.010 jopolito: Higher energy couple to be kinetic energy of the loads compared to. 236 00:43:45.120 --> 00:43:48.660 jopolito: Compared to conventional marks bank based system. 237 00:43:50.610 --> 00:43:52.680 jopolito: Oh, I didn't explain this part here. 238 00:43:55.200 --> 00:43:55.920 jopolito: So. 239 00:43:57.510 --> 00:44:06.810 jopolito: What you see here is the radius, this is the current the red solid line is the current for Ltd. 240 00:44:07.320 --> 00:44:26.610 jopolito: And for marks bank system, this is the dotted line, and this is the collapse trajectory of the gas pump and then we have the magnetic and kinetic energy and you can see a comparison between two systems again takeaway messages that Ltd. 241 00:44:27.630 --> 00:44:31.440 jopolito: Transfers the energy more efficiently into the Lord. 242 00:44:33.030 --> 00:44:48.810 jopolito: I told you, one reason is in gotten there are other reason in the March bank system they are many stages of energy transfer, but in Ltd, they are not too many stages so that's another difference between two systems. 243 00:44:52.560 --> 00:44:54.150 jopolito: Okay, let me skip this. 244 00:44:58.770 --> 00:45:06.960 jopolito: So the experiment that I showed we didn't use the external magnetic field, so I forgot to mention, but here, you see. 245 00:45:08.730 --> 00:45:16.680 jopolito: Recently we have carried out experiments, where we use we don't change the target gas target gases always deuterium. 246 00:45:17.730 --> 00:45:30.420 jopolito: In this case we use the liner we use from deuterium liner to krypton liner and you can see that instability amplitude increase with the as we are increasing the. 247 00:45:30.960 --> 00:45:47.190 jopolito: Z number of the liner again that goes back to the argument that I was making as you are increasing busy, then the radiation effects are playing an important role, but there is also a role of resist devotee of which we are investigating. 248 00:45:48.810 --> 00:45:59.700 jopolito: Okay, so let me skip that we are expanding the diagnostics, we have developed grazing incidents spectrometer we are. 249 00:46:00.750 --> 00:46:10.680 jopolito: One of my students PhD work is on semen polarization spectroscopy we are using that to see the magnetic field distribution. 250 00:46:11.730 --> 00:46:20.430 jopolito: And we are developing Thompson scattering diagnostic so we would be able to obtain more plasma parameters with this diagnostics. 251 00:46:22.530 --> 00:46:28.230 jopolito: Okay let's Let me move on to magneto relative Taylor instability. 252 00:46:29.400 --> 00:46:37.830 jopolito: Which is pretty common in gas policy changes so, as I said when I started my presentations there are two mitigation techniques, one is. 253 00:46:38.280 --> 00:46:52.860 jopolito: External magnetic field or Axial magnetic field and other is the density profiling, so you can see the instability growth, this is the acceleration and you can use the magnetic field and density profile to. 254 00:46:55.410 --> 00:47:13.050 jopolito: To mitigate and, as I said that the experiments have been done, I already showed this results, this is from Eric lemon at cornell university his recent paper talking about the effect of magnetic field on on the mitigation of magnitude related and instability. 255 00:47:14.910 --> 00:47:17.850 jopolito: So def not case, who was. 256 00:47:19.080 --> 00:47:21.090 jopolito: student and postdoc in my group. 257 00:47:22.560 --> 00:47:37.650 jopolito: carried out read Hydra simulation where he used to liners, so let me explain what this diagram is this is the central get details from what we call target or few, then you have inner. 258 00:47:38.820 --> 00:47:49.800 jopolito: Shell and then an outer Shell and what he did he changed the material of inner Shell and outer Shell he used a variety of. 259 00:47:50.880 --> 00:48:02.670 jopolito: gases that I will show you in the next slide So these are the parameters for the experiment, this is the machine, we have at ucsd and the damages and the density that he. 260 00:48:03.210 --> 00:48:18.780 jopolito: used to make sure that the mass the total mass we have is enough to class the pinch on the access so that's what you need to make sure that whether you're using otter Line two lines or three lines you need to keep the mass. 261 00:48:19.800 --> 00:48:32.040 jopolito: The same whether you, you are using a single liner so the pinch happens or the class have fans are bang happens at the at the current maximum. 262 00:48:33.750 --> 00:48:34.770 jopolito: So he did. 263 00:48:35.940 --> 00:48:37.320 jopolito: four year transform. 264 00:48:39.000 --> 00:48:52.740 jopolito: analysis of the data, this is without magnetic field neon liner detailed em no magnetic field, and you can see, the two millimeter wave length is dominate. 265 00:48:53.700 --> 00:49:06.540 jopolito: If you look at the function of time, however, when he applied the magnetic field of point seven tesla, then you see some reduction in the instabilities here but. 266 00:49:11.040 --> 00:49:23.640 jopolito: If you are using to liners, in this case neon neon liner, and this is the line where two liners much before collapsing on the target, so you can see that the instability. 267 00:49:25.740 --> 00:49:40.710 jopolito: Growth there's a difference in instability growth, but my takeaway message from this slide is that when you are applying point three tesla magnetic field not point seven tesla magnetic field, you can see that your instability. 268 00:49:41.460 --> 00:49:55.170 jopolito: Growth is significantly reduced so that's what I wanted to show you that you can use external magnetic field, you can use density profiling by using multiple liners. 269 00:49:55.620 --> 00:50:12.150 jopolito: Or you can use a combination of density profiling and external medic magnetic field to mitigate the magneto related or instability and that's, to our knowledge, this is the first time this has been done. 270 00:50:15.180 --> 00:50:25.320 jopolito: Oh, I don't have enough time Okay, so let me scape there were few other interesting things we did we use, as I said, various materials. 271 00:50:26.760 --> 00:50:28.770 jopolito: In the inner and outer liner so. 272 00:50:30.810 --> 00:50:45.870 jopolito: The takeaway messages increased compression from higher the wiki krypton liner increase BC feed line tension, Sir, reduce Mr ti growth what we did. 273 00:50:46.560 --> 00:50:59.940 jopolito: So these are for one mega generator and he carried out the experiments for 1010 Meg as well, and for 10 Meg and he showed that you can generate tend to the 13 to 10 to the 14. 274 00:51:00.960 --> 00:51:07.980 jopolito: neutrons for sure if you are using double liner or triple liner. 275 00:51:11.130 --> 00:51:17.910 jopolito: One thing I forgot to mention when you are applying external magnetic fields your neutron G goes down. 276 00:51:18.750 --> 00:51:25.920 jopolito: Right and what he found out that if you're using density profiling in a combination of external magnetic field. 277 00:51:26.340 --> 00:51:32.910 jopolito: Is your neutron gene is not compromised and if you're doing few years of research, you don't want your neutron you to go down. 278 00:51:33.540 --> 00:51:42.690 jopolito: So that's a good message one worry was that Okay, we are using this variety of Z material what will happen to the mixing mixing is a. 279 00:51:43.020 --> 00:51:55.110 jopolito: big issue, whether you're talking about international confinement fusion, I believe that the issue in megalith as well right concern that what mixing will do to the target, so what he did she. 280 00:51:56.340 --> 00:52:09.660 jopolito: He saw that there was a 10% mixing by volume of the liner gas into the into the target it didn't decrease the neutron yield significantly so that that's the good news. 281 00:52:12.480 --> 00:52:13.470 jopolito: Any questions. 282 00:52:18.480 --> 00:52:38.520 jopolito: Okay, in the last five or 10 minutes I have is that I want to move on to dense plasma focus, so we have carried out experiments on to mega machine and also at ucsd we have 300 kilo and machines. 283 00:52:42.210 --> 00:52:48.720 jopolito: As I said, dense plasma focus is in the family of Z pinches electrode configuration is. 284 00:52:49.890 --> 00:52:56.610 jopolito: slightly different, so let me show you how it works, so what you have this can get hot rods all around. 285 00:52:57.570 --> 00:53:16.470 jopolito: In the cylindrical form so it's basically a coaxial gun right, and then you have handled in the Center, and this is your insulated sleep so when you apply the voltage the breakdown takes place and the Jay crosby force lift the current sheet from insulators Lee and it moves. 286 00:53:18.030 --> 00:53:23.520 jopolito: Along the anode do to get across be force in shape of umbrella. 287 00:53:24.840 --> 00:53:27.900 jopolito: And then it collapses on the top of the anode. 288 00:53:29.010 --> 00:53:37.110 jopolito: that's why it's called dance plasma focus, are you are, you are getting focus plasma on the top of the enemy. 289 00:53:39.390 --> 00:53:50.010 jopolito: And these are various phases what we call breakdown phase Axial rundown says, and the radio clubs face, and this is one of the images from our machines. 290 00:53:51.930 --> 00:54:00.090 jopolito: This is by the way, sure and images So you see plenty of structure formation instability formation in the pinch region. 291 00:54:03.030 --> 00:54:06.750 jopolito: Whether you're doing cpt research or dance plasma research. 292 00:54:07.890 --> 00:54:19.260 jopolito: You are going to come across this scaling what we call it the for scaling that's the neutron yield scaling as a function of P current. 293 00:54:19.890 --> 00:54:35.310 jopolito: So higher the concern more neutron you are going to get so this is taken from Krishna and review Article in ieee transaction on plasma science, so you can see our 2.7 megabits. 294 00:54:36.480 --> 00:54:57.480 jopolito: experiment here producing tend to be 11 neutrons and our ucsd experiment producing tend to be eight neutrons one of the key questions in dense plasma focus is how would you increase the neutron use, are there any ways that you can increase the neutron yield. 295 00:54:58.830 --> 00:55:18.300 jopolito: Or you can change this scaling another interesting thing our colleagues have discovered at Lawrence livermore national lab and also in albuquerque that if your current is going above few megan then your yield is turn off. 296 00:55:19.770 --> 00:55:34.740 jopolito: So in dance plasma focus neutron Julius produce due to to mechanism, one is being target interaction and also due to thermo nuclear fusion, so if you are going to hire current then being target interaction. 297 00:55:35.880 --> 00:55:49.260 jopolito: phase of is switched off so So if you have saturation of neutron G that few megan can you increase that neutron G that's, the question we try to address. 298 00:55:49.800 --> 00:55:59.880 jopolito: On that machine and you again I don't have time, what I want to show you here is the current wave form, and these are the neutron time of flight data. 299 00:56:03.450 --> 00:56:06.420 jopolito: In these experiments we use. 300 00:56:09.180 --> 00:56:17.640 jopolito: Different impurities are open, for example, we for the open of krypton point 1%. 301 00:56:19.980 --> 00:56:34.650 jopolito: At 35 kb and 2.29 mega and that's for sure the rundown time that rundown time of the sheet, I was talking about this is the neutron good, but let me show you what is exciting on the next slide. 302 00:56:38.220 --> 00:56:47.430 jopolito: Can you see that act 2.29 Madame when we started to increase the doping percentage in detail right. 303 00:56:48.480 --> 00:56:53.550 jopolito: There was a modest increase in neutron jail and as we increase. 304 00:56:55.050 --> 00:56:58.800 jopolito: more open than the neutron just went down. 305 00:57:00.570 --> 00:57:06.960 jopolito: However, when we increase the voltage and slightly increase the current look what happened to the neutron youth. 306 00:57:08.730 --> 00:57:10.590 jopolito: It got increased significantly. 307 00:57:11.610 --> 00:57:29.160 jopolito: And then you when you increase the dope and then it dropped, so, if you look at the comparison of pure titanium blue line here they are two data points we are going to go and do experiments on different current level. 308 00:57:30.990 --> 00:57:34.320 jopolito: And look at the red line where we added the krypton. 309 00:57:35.730 --> 00:57:42.630 jopolito: This significant change in neutron jail and the scaling moves from it to the fourth to the to the six. 310 00:57:44.490 --> 00:57:47.040 jopolito: So a small percentage of the open. 311 00:57:48.120 --> 00:57:49.710 jopolito: has increased the neutron year. 312 00:57:51.150 --> 00:57:51.570 jopolito: Why. 313 00:57:55.170 --> 00:57:58.800 jopolito: Anyone want to have a guest user. 314 00:58:00.270 --> 00:58:07.470 jopolito: And you go, so if you are krypton is high, as a gas right so when you are putting that percentage. 315 00:58:07.740 --> 00:58:19.080 jopolito: Then they are radiation effects and the world, I used previously radiative claps so you have radiative claps which is increasing your neutron he you are getting tighter pinch. 316 00:58:20.070 --> 00:58:32.190 jopolito: giving you high and neutron yield, then you may ask, so why radiative collapse is not happening, when you are increasing the percentage thing is there you are putting too much there is. 317 00:58:33.240 --> 00:58:39.870 jopolito: Is that the balance of energy that you need to find you don't want your. 318 00:58:41.370 --> 00:58:56.790 jopolito: detail detail em dominated by krypton so it starts to behave like krypton right so and what we think we haven't done this simulation that will be something interesting to do I think in dance. 319 00:58:57.270 --> 00:59:08.880 jopolito: zipping that's kind of a State zip and because deuterium is collapsing and krypton is heavier so maybe there's another current shape or form which is collapsing on the carrion so. 320 00:59:10.020 --> 00:59:15.990 jopolito: So this was, I think I have ran out time and we made a comparison with. 321 00:59:18.060 --> 00:59:29.610 jopolito: With the other experiments done on a smaller current level, and you see the comparison here, so there is a relationship between peak neutron Yun and percentage of. 322 00:59:30.150 --> 00:59:40.620 jopolito: krypton volume fraction we came up with this relationship, which is in Afrikaans paper in general have applied physics, again I don't have. 323 00:59:41.790 --> 00:59:44.460 jopolito: Time to go through all this. 324 00:59:46.050 --> 00:59:57.120 jopolito: Another interesting thing we saw that is when you are putting percentage of krypton then this, these are neutron time of flight signal. 325 00:59:58.350 --> 01:00:05.430 jopolito: Then you squeeze your neutral time of five signals become narrow compared to pure deuterium. 326 01:00:06.180 --> 01:00:22.320 jopolito: And that is consistent with what I just said that if you have radiative claps, then you are going to have tighter pain, because these are radiation loss and and you're pinching your plasma to smaller diameter, you are making hotspots. 327 01:00:25.050 --> 01:00:36.570 jopolito: Let me and we carried out Hydra simulation to understand this Hydra similar Hydra is ma decode it doesn't take into account beam target interaction so. 328 01:00:36.960 --> 01:00:44.550 jopolito: is purely what is coming out to to thermo nuclear fusion nature and we saw that if you're using. 329 01:00:45.540 --> 01:01:13.890 jopolito: krypton percent a then we get much thinner shades there was a disagreement between experiments and modeling, as I said in our experiments we use point 1% of krypton but in simulation, we have to use 1% of krypton to see the effect on the sheet formation or 10 sheet so again. 330 01:01:15.360 --> 01:01:19.500 jopolito: it's a good that if you have a disagreement between modeling and experiment that. 331 01:01:21.240 --> 01:01:24.210 jopolito: These are some thinking you need to do. 332 01:01:25.920 --> 01:01:29.460 jopolito: Okay, so I don't think I have time to go through. 333 01:01:31.410 --> 01:01:47.250 jopolito: them rest of the material, but I like to close here by saying that you can see here, as I mentioned in the previous slide that peak current versus thermonuclear neutron G and the data we have that we have neutron. 334 01:01:48.660 --> 01:01:57.900 jopolito: With the percentage of krypton the scaling changes from I could afford to be it to the six birthdays more experimental data needed. 335 01:01:58.980 --> 01:01:59.700 jopolito: and 336 01:02:02.280 --> 01:02:08.790 jopolito: And i'll leave the summary here Thank you so much for your attention and i'll be happy to answer any question you have. 337 01:02:14.220 --> 01:02:17.580 jopolito: about very nice Ruby questions here in the room. 338 01:02:21.990 --> 01:02:23.820 jopolito: i'm in the. 339 01:02:25.320 --> 01:02:26.070 jopolito: DPS dpf. 340 01:02:27.210 --> 01:02:42.840 jopolito: of measurements, you had the side on and on and on, on our yields for the insurance you orient he decided and what he said and done, in the context that and using the tax so be have us. 341 01:02:44.220 --> 01:02:46.740 jopolito: If I understand your question correctly. 342 01:02:47.760 --> 01:02:51.600 jopolito: The use of neutron detection side on and on right. 343 01:02:52.680 --> 01:03:12.360 jopolito: So the reason we use and other angles, as well, is that an ISO trophy, which is important right if you have thermal nuclear fusion neutrons whether your detector is on site on direction or and on direction just ignore the scattering, then you should have similar. 344 01:03:14.100 --> 01:03:22.020 jopolito: neutron energies right there shouldn't be any upshift or down shapes but if it's due to beam targeting direction, then you will see up or. 345 01:03:22.350 --> 01:03:31.650 jopolito: Down shift of neutron energy, so it is important, whether you're using gas pumps or dense plasma focus to have neutron detectors in. 346 01:03:32.100 --> 01:03:55.050 jopolito: at different angles and different directions to see what is the nature of neutron G again, one has to go in depth analysis of neutron data to say how many neutrons are coming due to beam target and how many are coming due to thermonuclear fi in the data, you know and on utah utah. 347 01:03:56.130 --> 01:04:02.460 jopolito: To a higher than your side on sounds a bit confused, but where the end on inside of detectors all costs. 348 01:04:04.050 --> 01:04:04.920 jopolito: Which slide was. 349 01:04:09.900 --> 01:04:10.560 jopolito: For this. 350 01:04:12.900 --> 01:04:13.740 jopolito: yeah this slide. 351 01:04:15.780 --> 01:04:21.540 jopolito: So I am not sure here. 352 01:04:22.650 --> 01:04:34.800 jopolito: So you need to keep in mind that dispenses may be different you're sharing maybe different neural if you are using lead shooting it shouldn't affect the neutron. 353 01:04:35.880 --> 01:04:42.690 jopolito: g it reduces the gamma Ray signal, but the distance could be different, thank you. 354 01:04:44.610 --> 01:04:45.870 jopolito: Everyone down here in front. 355 01:04:48.120 --> 01:04:49.050 jopolito: Of you consider other. 356 01:04:51.030 --> 01:04:52.470 jopolito: that's a great question and. 357 01:04:54.570 --> 01:05:05.820 jopolito: We are getting interesting results with Oregon The next step is using on which is significantly higher G the problem within on is that is massive right. 358 01:05:06.900 --> 01:05:16.500 jopolito: So to accurately know what percent you have in the gas is extremely difficult, so we are working on that, yes, absolutely that's enough. 359 01:05:19.500 --> 01:05:24.210 jopolito: tricks to fall to prevent gas mixing as you go to multiple shields. 360 01:05:26.640 --> 01:05:28.590 jopolito: shells multiple shows. 361 01:05:29.640 --> 01:05:31.350 jopolito: Oh, so the. 362 01:05:33.180 --> 01:05:36.870 jopolito: that's a great question so magnetic field. 363 01:05:38.610 --> 01:05:47.160 jopolito: You want to don't want to have conduction as well, so magnetic field definitely helps to a wide mixing. 364 01:05:52.950 --> 01:05:57.210 jopolito: Your experiments changing you know liner materials from. 365 01:05:58.230 --> 01:06:07.230 jopolito: me on krypton do you have a character character is the density of those shows, so you showed that. 366 01:06:08.430 --> 01:06:10.050 jopolito: tyrese materials had. 367 01:06:11.700 --> 01:06:13.080 jopolito: A larger amplitude. 368 01:06:14.280 --> 01:06:20.550 jopolito: Really dealer growth, do you have a characterization of the Shell density your liner. 369 01:06:21.750 --> 01:06:25.800 jopolito: characterization before we pass the current in fact yeah. 370 01:06:27.240 --> 01:06:41.910 jopolito: So that's we were having this discussion this afternoon, so characterization is extremely important, we don't have insensitive characterization, because if I said that it could be. 371 01:06:43.170 --> 01:06:47.370 jopolito: density profile initial density profile could be different, so now. 372 01:06:48.600 --> 01:06:49.860 jopolito: We don't know we. 373 01:06:51.180 --> 01:06:52.020 jopolito: tracked rise. 374 01:06:53.100 --> 01:07:07.860 jopolito: You know outside in another lab, but what is happening in the Chamber Chamber that's a different issue Another issue is the ionization so we start with the insulator right so and they have, if you look at neon and organ. 375 01:07:09.240 --> 01:07:18.930 jopolito: The ionization energies are different, and that those could also play they're all hot the gas his break down that's a great question. 376 01:07:21.780 --> 01:07:28.860 jopolito: I think i'll just wrap it up with one last quick question really nice job your group church rising the implosion kinetic energy and. 377 01:07:29.490 --> 01:07:39.780 jopolito: coupling efficiency around 8% and I was just curious if you guys tried to measure like total energy total extra energy coming out with a kilometer or something that maybe. 378 01:07:40.500 --> 01:07:49.980 jopolito: My what i'm thinking is that the kind of guy just part of that, but then there's also like there's a anomalous resistive it or something that can be eyes only eating an iceberg arguable even further enhance that. 379 01:07:50.760 --> 01:08:11.670 jopolito: Efficiency that may be something 20% or right, so now we haven't used, yet we do have we that's again next step, but we use the dialer sprint out, so what we did we use Ross filter pair so we can get the cash cow chilled out for that gave gave us idea okay. 380 01:08:13.500 --> 01:08:16.350 jopolito: All right, any last minute questions. 381 01:08:18.030 --> 01:08:19.260 jopolito: or speaker another round of applause. 382 01:08:24.210 --> 01:08:26.190 jopolito: Thanks everybody for coming see you next time. 383 01:08:48.180 --> 01:08:48.690 jopolito: Oh well.