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Mark Kushner: She is. Yes.

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Mark Kushner: and their interests and passion and visualizing material behavior in most

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Mark Kushner: is my pleasure to this is still a great honor. Oh, hey, let's see Mulligan.

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Mark Kushner: which is

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Mark Kushner: all right.

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Mark Kushner: Good afternoon.

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Mark Kushner: It is my great pleasure to be with you here today. My name is Ariana Gleason. I'm. From slack national Lab and Stanford University. And today I'm going to share with you my vision, my perspective on high energy, density, science.

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Mark Kushner: and leveraging a new lens. On looking at these materials at extreme conditions, using a whole suite of of diagnostics to tackle some grand challenge science questions in our community.

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Mark Kushner: So I wanted to start out by saying it's such an exciting time in high energy, density, science from exploration of exoplanets and understanding their constituent materials, understanding the equation of state of materials that extreme conditions that dictate.

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Mark Kushner: how a planet evolves. Can it sustain life? These are all integral questions that we need to address as we look forward to think about the possibility of life elsewhere in our universe.

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Mark Kushner: thinking about our own planet, the interior of our, of our mantle of our core. How that influences our daily lives

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Mark Kushner: also in impact scenarios When a planet forms these dynamic compression, instantaneous sorts of events also at extreme conditions, we can learn a great deal by leveraging experiments in situ in our laboratories.

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Mark Kushner: designing novel materials. This is an entirely new frontier, where laser matter, interaction. Think of additive, manufacturing. Think of achieving novel thermo dynamic paths where you achieve a material state, a metastable state. Quench it, but you can use it in your everyday life in certain applications. This is another way. We can tune high density, a high HD. Science in an application space.

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and then the more traditional, maybe what you you hear more of in these seminars on a on a monthly basis.

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Mark Kushner: a whole spectrum of HD. And and foundational plasma science from looking at materials at the interiors of of Jupiter or stellar interiors, but also in an application such as fusion, energy, science, and we're going to hear about that a little bit more in, as i'm. Sure you've heard the 2,108 shot on the niff.

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Mark Kushner: which achieved a a remarkable yield over what was input. And achieving the first burning plasma. And so in dynamic compression and material sciences at extremes, we use a whole host of of tools to achieve those extreme conditions.

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Mark Kushner: We can leverage shock, compression, and sort of give you multi 1 million times our atmosphere to generate the conditions of our own earth's interior. We can look at high temperatures, thousands of Kelvin up to many times ev

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Mark Kushner: different radiation environments. We can impose different pumps to distort, to modify, to affect our material at these extreme states.

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Mark Kushner: And so there's a whole host of disciplines, some of which i'll. I'll touch upon most of the work you'll see today is dynamic materials research. But then i'll also venture into some aspects where i'm trying to pull across disciplines and we'll actually talk about astrobiology and exobiology.

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Mark Kushner: So how do I do this. My main tool being at slack is access to, I think, one of the world's most fantastic cameras. So the Linux coherent light source. The Lcls at slack

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Mark Kushner: is essentially a a 2 mile long, atomic scale. Oh, is this in the way? Oh, yeah, You know that's great

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Mark Kushner: atomic length, scale camera, and we are able to execute snapshots of materials not just condensed matter, but also plasma states exploring chemistry, physics.

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Mark Kushner: and biological systems with femtosecond temporal resolution. So what does that mean? Some 2 s are shorter than a phone on period. So when we take these free strings, when we take these snapshots, whether it's diffraction.

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Mark Kushner: X-ray imaging or spectroscopy shorter than a phone on fear. Period means we're really taking an individual frame we are not blurred over over that phone on vibrational period of time. Moreover, our Linux is tunable. We can achieve from the soft energy, soft X Ray energy regime. Down to the carbon edge we go from the carbon edge

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Mark Kushner: 200 or so ev all the way up to 25 kev and the hard x-ray regime so there's a whole range of different applications of of a of an X-ray probe, such as that we currently operated 120, hertz, but we're looking forward to an upgrade, where we'll be able to run it a megahertz, and this will be key as we push forward into certain kinds of testing for fusion, energy, science applications. We're we're running at a particular rep rate

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Mark Kushner: is is important.

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Mark Kushner: So I want to pause for a moment, talk a little bit more about the light source itself. So when I say, an X-ray free electron laser. What I essentially mean is we have our accelerator but our undulator call the magnets of alternating

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Mark Kushner: polarity

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Mark Kushner: force the electron beam to to oscillate. And over such a length scale we're able to have those X rays operate in phase, and that phase gives us coherence and brilliance.

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Mark Kushner: That is 10 to the 9, a 1 billiontimes brighter than any traditional synchron X-ray based light source that that we have now the original Lcs. When it first was brought online in early 2,010.

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Mark Kushner: It was a was a it was a great hit. It was the first hard X-ray free electron laser and operation. And now there's there's been a blossoming around the globe for different x-ray free electron lasers in in Japan, in Germany currently it's a sister facility in at the European expel called Hi Beef.

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Mark Kushner: has sort of a a a similar footprint as to what i'll talk about today in the matter and extreme conditions touch.

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Mark Kushner: But the point is that we're leveraging this in phase capability for the coherence and the brilliance and one piece, One example i'll share with you in in the context of X-ray imaging is the ability to go, not just in a face. Contrast regime, but to actually push out into the holography and coherent X-ray diffract Div. X-ray regime, and this allows us to capture more of the higher resolution that's needed, and 3

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Mark Kushner: mapping of materials at these extreme conditions. So that is a a benefit that we will walk through a case study today.

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Mark Kushner: So we couple this really exciting probe, this x-ray probe that allows us to visualize changes in materials in real time

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Mark Kushner: with a a pump. So my end station or or the end station the very last. It's a very last hutch that we have in our in our 2 mile long.

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Mark Kushner: The footprint is the matter in extreme conditions and station, and currently we're looking forward to an upgrade. But right now, as it stands, we have a long pulse laser. That's about 60 jewels so I heard from Karl today that you all will have a 75 joule long course laser, which is fantastic. So we're we're we're even a bit below below you. Currently we do have a a what's called a pimple or a goal to achieve a 100 joules

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Mark Kushner: in 20 nanoseconds, and hopefully that'll be online in a matter of months.

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Mark Kushner: So we've got about a 100 joule laser, long post laser. Once every 7 min we're able to fire, so certainly not it. At rep rate at at this point, and then we have a smaller, short, close laser. That's also getting upgraded to a 500 terra watt system, and most of the work i'll talk about today. I'm not a short pulse. Laser girl. I'm long pulse laser. But there's a number of exquisite studies that have come out also on our short pulse laser side

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Mark Kushner: looking at a, at a variety of phenomena, from laboratory astrophysics to to a diagnostic development. So at the heart of it I'm. Executing a series of pump probe experiments. So my pump is the is the drive laser, so I've got some sort of spatial

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Mark Kushner: way of imprinting my my drive laser intensity on my target. I often have an ablator here, and it is

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Mark Kushner: a blading, generating a plasma that blows off. And, as you know, following Newton's third law equal and opposite, we launch a shock wave in the other direction, and I take advantage of that shock wave transiting through my material, and I use a series of of traditional and novel probes to watch, to follow at the at the atomistic scale. So I get to sit next to an atom and actually watch, visualize how it is transforming in that high pressure high tech

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it's a.

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Mark Kushner: And so the traditional diagnostics. Maybe you're familiar with the lot symmetry. So, looking at motion of a rear surface that tells you the shock, pressure, or or the the particle velocity and the shock velocity, and coming up, maybe with an equation of state.

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Mark Kushner: But leveraging these novel, X-ray diagnostics. These are a few examples of capabilities, and from these different capabilities, diffraction and imaging in particular, we're going to walk through a a series of case studies. And so this is actually the outline of the talk.

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Mark Kushner: So we finally arrived. We're going to look at iron. We're going to look at iron, at our our earth's core condition. We're going to think about reology and how that influences. Maybe our magnetic field.

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Mark Kushner: We're going to talk about void collapse or imperfections and materials that are important for future Icf inertial confinement, fusion. And if you inertial fusion, energy applications.

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Mark Kushner: and then I'm gonna totally turn this around. And i'm actually gonna combine techniques that we've just talked about depression and imaging and pulling a chemistry thread and think about the origin of life, the shocking origin of life.

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Mark Kushner: So let's start on this journey. First we're going to start out here. On Earth. We're going to dive about 6,000 kilometers below your feet, and we're going to think about the inner core. Now the inner core is a weird place, all right. There's a innermost inner core. It's kind of lopsided right, you think. Oh, maybe it's like a perfect sphere, not the case.

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Mark Kushner: There are different hemispheres. There's differences in crystallinity as you go from the innermost inner core, outermost inner core. It's about the size of our moon, and as hot as the surface of the sun. All right. So this is really one of the main engines of our planet, and mineral physicists have studied

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Mark Kushner: the inner core and iron actually, BCC. Body center cubic iron at high pressure conditions transforms to an Hcp. Hexagonally close-packed structure. And you might think that a mineral physics by now, after 50

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Mark Kushner: or so years of investigation, you might think that as this hexagonally close-packed structure

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Mark Kushner: these crystallites are, are are growing so that's the other thing that's interesting is the inner core is growing the the liquid outer core. It's precipitating out in the inner core is growing, and eventually it'll it'll all freeze. But the alignment of those crystallites. So here's a a compressional wave speed as a function of that hexagonal axis, right?

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Mark Kushner: And so seismologists observed tens of years ago, that compressional wave speed when you have a a seismic event, an earthquake, the compressional wave speed. This body wave travels about 3 to 5% faster in the in the polar direction than in the equatorial direction.

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Mark Kushner: Paul. That's strange! Why would that be? Well, it gets back to the mineralogy. It could be that that c. Axis of the hexagonally close-packed mineral is somehow aligned right to be, maybe the fast or the slow direction. But you can see that actually mineral physicists, whether they're experimentalists or modelers can't agree.

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Mark Kushner: So we we embarked on a on a question to understand how what is the mechanism by which

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Mark Kushner: possible crystallites of Hcp iron could be shaped, could generate this fabric, or this anisotropy in the inner core, and it has to do with plasticity, has to do with the strength, the intrinsic strength of iron at these conditions. But it turns out that this is really hard to measure.

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Mark Kushner: So. In the static compression community we developed a a a an approach called radial X-ray diffraction. What that means is, if you have a device such as it's called a diamond amble cell, so something that holds high pressure for long periods of time if you actually probe about perpendicular. So here's our X rays.

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Mark Kushner: The diamond animals are here. If you pro perpendicular

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Mark Kushner: to that uniaxial stress, you'll have access to this this waving. This you might think, if a material is totally hydrostatic.

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Mark Kushner: when you take a slice through those d by sheer cones when you're when you're looking at wide angle X-ray scattering, if it's totally hydrostatic, you should see a perfect circle but if you have something that's more oblate, it means there's some intrinsic

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Mark Kushner: strain in the system and the magnitude of that string. If you were to snip and unroll those device, shear cones, or that slice through the device share Cone, you'll see waviness and the extent of that waveliness, how much it it it the perturbations tells you information about the strength.

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Mark Kushner: Moreover, you might notice that along these lines there's clustering of intensity. So this texturing or preferred orientation also gives you information about the magnitude of of the dependence on each individual hkl, each plane.

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Mark Kushner: the the stress and the strain in the system.

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Mark Kushner: So we can leverage radial radial X-ray diffraction to extract information about the strength. Now we did this in a diamond animal cell. We got an answer, but that was all. At room temperature. Now what what was brought to us was all we should really do this at the at the P, the pressure and the temperature conditions of the earth's core.

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Mark Kushner: So we did that by using laser-driven shock compression

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Mark Kushner: where we can achieve a point on the Hugonio, something like 200 Gpa and several 1,000 Kelvin. But the trick, you know, I I mentioned this radial aspect of the of the diffraction. To do that for a laser based design is actually really hard to do so. We did our best to have appropriate coverage of the diffraction. Now, this doesn't look like much. But if I here's the the raw data. Oh, excuse me, here's a reconstruction. The data is down here.

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Mark Kushner: so you can see if this were a perfect coverage of my detector, I would see some of these lines of http iron. They should extend all the way up, but you can see my coverage is sparse.

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Mark Kushner: but at least what I've been able to map out in this pull figure is that I have measurements of the the the magnitude of the the appropriate stress fields. In my diffraction

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Mark Kushner: I can compare that to a model using this cloud material analysis software that gives me that where I propose a plasticity model and a stress state.

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Mark Kushner: i'm gonna take just a quick aside. I need to remind you about pull figures. I'm sure you all are aware of this phenomenon. But if you have a crystalline material, and you want to project, it's orientation, or that's a object, but we want to project it in a in a one dimensional or 2 dimensional way. We have to use these these.

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Mark Kushner: these different mechanisms, these pole figures. And so here's my crystallite of http, and I want to remind you that if we have a twinning texture so different grains of metals, they can form a twin, which basically is a like a mirror axis in the grain. And you have the same structure on either side of that mirror plane. So if we form a twin, we're going to have a maximum that's near the center of this inverse poll figure, and if we just are transforming to sort of randomly oriented Http.

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Mark Kushner: We'll have a maxima that's somewhere out here near the perimeter. Okay, that's the take home message. So let's talk about the example. The the actual experiment. So 2021. We worked with colleagues at University of Lil. So this was work.

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Mark Kushner: an association with Professors Sebastian Merkel. And so Here's a a fuzzy dive from Sorry of the of the equilibrium phase, diagram of iron

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Mark Kushner: and pressure and temperature. And so here's the Hugonio, and this blurry word. Here is a series one. So we're almost. Oh, we're so close to the meltdown, but not quite so. We're still solid iron. Okay, it's almost 200 Gpa. And if I look at the sequence of processes in time I can take time slices using the X Ray free electron laser to map out

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Mark Kushner: how the texture and strength is changing as a function of time. And so that's what's over here. So initially, I just see a a phase transform to Hcp. Remember, the maximum is out here, the perimeter.

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Mark Kushner: Oh, and look at this in about half a nanosecond. So point 6 to 1.1 nanoseconds I formed twins. Oh, my gosh! So this is forming a twin in about 500 picoseconds. This is incredible, because all of the models models up to this point to try to understand the strength and plasticity of iron have not had this level of fidelity in the experiments

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Mark Kushner: to benchmark the different mechanisms so we form we start out transforming, and then we form the twin twin twin. If we look at time, excuse me, stress state in the iron as a function of time just before it. Twins. Look at this just before twins. Iron is the strongest.

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Mark Kushner: and the mechanism to relieve that stress is the active 20.

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Mark Kushner: So that's really cool. We were able to visualize that. Okay, here's another plot that essentially describes what I just said, i'm gonna skip over for this final plot that says, compared to other ways in which we can look at the strength of iron at extreme conditions. So the actual inner core

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Mark Kushner: we weren't. We had a tiny laser, so we weren't able to get there. But here's my data in in the red data points. Here. The inner core outer core boundary is somewhere over here. That sounds a little scary doesn't it.

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Mark Kushner: and you can see that we we actually relax out at very high pressures. We relax out to a a lower stress state. What does this mean? Initially, in iron there is a maximum in its strength until it twins, and then it relaxes.

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Mark Kushner: We can look at, then try to understand what's going on here, and that the initial compression and the phone on drag in the material is actually dictating

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Mark Kushner: the mobility of these defects to relieve that stress.

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Mark Kushner: So this is iron, right? This is really exciting. We're able to benchmark, then a number of strength models, and that work is ongoing with colleagues at Livermore.

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Mark Kushner: Okay, pulling it forward. So what I want to do is expose or or share with you guys. A number of really cool X-ray diffraction techniques. I've talked about a solid state case here, right iron.

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Mark Kushner: But i'm well aware this is a plasma science seminar, and that you know the different flavors of X-ray scattering I list here, and maybe the the different opportunities, different information you can extract. But there's a number of ways in which this could be overlaid

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Mark Kushner: on to studies of the plasma states at extreme conditions as well. Talking about S. Of Q. Time Resolved structure, Factor looking at pair distribution functions of plasma, that extreme conditions, all of these things you could leverage in a time resolved way

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Mark Kushner: for different hed experiments. And so that's just something I wanted to share with you.

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Mark Kushner: Now, moving forward, this is case study number 2. So another part of my research focuses on the funny noise isn't it. Another part of my research focuses on thinking about materials used as ablation materials in Icf in inertial confinement fusion. So this is very much

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Mark Kushner: complementary connected with some of the work even done in this department in particular with.

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Mark Kushner: And so we know we have this wonderful success.

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Mark Kushner: The 21088 shot at the niff. Right? We got 1.3 megajoules of energy and part of what enabled that tremendous success that i'm sure you guys have heard about is the perfection, the level of effort in crafting the the the the capsule, in fact, the Hdc. The high density, carbon of later material. On the outside. It was exquisite.

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Mark Kushner: Millions of dollars went in to that one capsule in making sure it was perfection. But in the future, as we look forward to opportunities of inertial fusion energy

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Mark Kushner: spending a 1 million dollars per target at a rep rate that's never going to fly right. We need pennies, pennies for for for the targets.

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Mark Kushner: So, understanding how imperfections, how defects, how voids, blemishes in the later material influence, the compression

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Mark Kushner: of the capsule at extreme conditions in particular, following hydro dynamic instabilities from start to finish is part of a another motive, scientific motivation. And so here the emphasis of case study number 2 is actually looking at void collapse in

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Mark Kushner: a later materials for Icf. And to do this in in starting out I thought

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Mark Kushner: it's going to be really hard if we already have a few micron sized voids in an Hdc material in a, in a diamond material, or in a plastic that's going to be really hard to pull out and follow carefully at dialing in all the knobs and on my physics model, my transport properties, my strength.

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Mark Kushner: my equation of state, my radiation tracking these these different hydrodynamic instabilities. So I had to design a target. So this is work done by a former postdoc of mine. She's now faculty at Sorbonne University in in Paris.

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Mark Kushner: and she designed a really cool way to fabricate synthetic voids and targets, using photolithography, photolithography from sort of a

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Mark Kushner: micro electronics and industrial perspective is a well known architecture for building with regularity devices of things. So we leveraged a number of the tools in our in our Nano fabrication facility, and she was able to embed these tiny spheres. Now they're not as small as the blemishes and the voids in the Hdc.

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Mark Kushner: Targets on the niff. But they're an appropriate size, so that I can extract high resolution images and do 2 dimensional aerial density reconstruction. What does that mean? I can know at every point in my sample the density

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Mark Kushner: during this shock compression event, and I can feed that back into my physics models and see my am I getting it right? Have I thumbs up or thumbs down this physics model based on my data. So we pursue 2 experiments, and this is a bit of a confusing graph. But let's walk through one by one.

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Mark Kushner: So in this upper blue corner. What i'm illustrating

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Mark Kushner: is an experiment where I get to use 4 pulses of the Lcs of the X-ray free electron laser. They are each space by about a Nanosecond right? So I took 4 pulses. And that's perfect time scale by the way, because the amount of time it takes my

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Mark Kushner: shock wave to transit my sample that has this cute little void in it is on the order of Nanoseconds, so I can follow. It's not one. And done. I get multi multiple views of my sample as it's compressing, and as that void is collapsing.

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Mark Kushner: so that's this utility, where we leveraged collaborations with San Diego National Lab, and Livermore, to deploy what's called this Icarus v. 2 this ultra fast X-ray imager

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Mark Kushner: to track at the same gating period. So my X-rays come at about a nanosecond apart, and I can gate and in about that same way. So what this means is not all. My images are super posed on a single on a single screen, but I get them one by one.

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Mark Kushner: So that was one. We did it at 9 Kv. And we learned quite a lot. There was actually some refraction issues in the images

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Mark Kushner: that degraded our resolution. Okay, then, we pursued single shot phase contrast imaging. So we're in a different regime, okay, in terms of the optics, and we're at harder x-ray wavelength. What this means is, I have access to higher fidelity, spatial resolution. But I only get one sample per shot. So one and done so. I can't do this cute little pulse train, and like, make a movie of the well. I still make a movie, but each sample is is a different sample, so I have to do my very best, so that every single thing

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Mark Kushner: the sample is nearly identical, which is certainly possible with this photo lithography.

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Mark Kushner: Okay. So first I want to review with you the 4 the 4 pulse train. So this is really exciting. It's a capability of Lcls at slack that no other x-ray free electron laser has right. They have different bunch modes.

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Mark Kushner: So if you go to the European expel, if you go to sackl, if you go to PAL, they all have different operating modes, timing bunches that you can leverage. But for shock physics in particular, this one is really strategic, because the time scale is a few nanoseconds. So it's probably really hard to see

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Mark Kushner: on this Icarus V. 2, but we were able to shot and press our low void and get some curl up at the edges, and then some jetting at later times.

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Mark Kushner: and we compared these data to a a hydrodynamic simulation run by colleagues at Los Alamos and University of Rochester student Helen, graduate student, and so we got pretty good agreement. Moreover, again, remember, my my Holy Grail

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Mark Kushner: is 2D aerial density reconstructions. I want to know every single point without any priors. I don't want any previous information. I want to know from scratch what is my density right? Because that I can compare to to any physics model. And so we use what's called a T. Ie. Method. So this transport of intensity method.

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Mark Kushner: fantastic postdoc out of Los Alamos national lab took these data, but the Ti method. It's a little bit Sus, right? Because what we're doing is something. My kids say what we're doing here is just focusing on a single material. So either you get the density of the polymer that is holding the void or the void of material itself. Some detail I lost over. Was it? The voice themselves

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Mark Kushner: are technically a one micron shell of glass.

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Mark Kushner: So technically there's 2 material there.

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Mark Kushner: But anyway, so we are able to come up with with the 2D density reconstruction here. But the resolution is for right. You would look at this, and you're like, yeah, that looks not so good. So the science. So this demonstrates a technical capability that we can track with 4 frames. It was a starting place.

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but the the science lives in the high resolution images. Okay, because I want to track that curl up.

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Mark Kushner: So here's in jetting plasma jetting as the void collapses. So here's a single shot. Result. So again, here's my 9 or 8 Kv. Data. We only had to 50 Gpa: not very high pressure, and then look at my void right? This looks. This looks thick. It looks fat. What's going on here? The reason why the image on the left

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Mark Kushner: looks sort of low, lower resolution is because we have refraction effects in the in the imaging right?

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Mark Kushner: So this is something to be mindful of going forward, whereas it the 18 Kv. We don't have these effects. So there's a little bit more clarity, and what we were able to do at 18 Kv. Is get up to much higher pressure a bit over 200 Gpa. Both of these studies have now come out from a a graduate student at by you, Daniel Hodge.

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Mark Kushner: so you can look those up. But the benefit here is we're able to get spatial resolutions at 18 TV 200 Gpa. VoIP collapse compared with the 2D. X rage down to 400 nanometers. Oh, that's great, and we are working toward getting the 2D aerial density reconstructions in the shock image. And so here's I told you I wouldn't show you a video, but I did, anyway. So here's this is for the 18 Kev data, and you can see

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Mark Kushner: at later times there are these little. It's like a little Smiley at the end. This is the edge. Curl up, and what you what? We're having trouble witnessing in these images, and we're working to clean it up, using a a series of strategies, principal component analysis, and the like is the actual jetting after. At much later times.

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Mark Kushner: after the void has completely collapsed. And so that's sort of the next step.

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Mark Kushner: But the data that we do have so this is so. These are still images. This is raw Data X Pci: data up here, and we're comparing that directly to what the corollary should be in the X rage and the next steps here. Oh, I wanted to share with you an exciting piece that we also had

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Mark Kushner: veloc symmetry running at the same time, and interestingly, on certain shots where we actually the highest pressure shots. We we saw this in our velocity. So you see, the the vis, our data is actually not very good, but we actually get thermal emission from the plasma

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Mark Kushner: at certain shock pressures. And so what we think we're seeing here is time resolved

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Mark Kushner: toroidal plasma mission at at our highest pressures. We refer to this as the lorax mustache. And you see that movie laurex. Okay. So this is the void collapsing. And then you see this, these. It's a cross section of that toroidal structure, and it's similar to what's seen in in some previous work.

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Mark Kushner: So we're looking into that to try to constrain some aspect of temperature, though admittedly so. This is just the last symmetry, and it wasn't calibrated as a street optical pyrometer would be

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Mark Kushner: so moving forward with the imaging as I mentioned, these images look messy right. We see lots of lens. We use a compound refractive beryllium lenses to focus the X-rays and execute these imaging experiments, but they have blemishes on them. They have dust.

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Mark Kushner: they have boogers. We don't know whatever they've got a lot of stuff on it in lieu of having cleaner lenses, which one could do. If one has a 100 K. We have to come up with a way of doing white field subtraction. So that's part of what

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Mark Kushner: white field normalization that was completed by the graduate student by you, but also principal component analysis, which is another strategy for looking at different modes

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Mark Kushner: in in the image and subtracting them off. And our colleague, Andrew Liang, at at Los Alamos national Lab, has been able to do

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Mark Kushner: 2 dimensional aerial density, reconstruction on a static image, and is working on the shock. Compressed state now. And so that's moving forward. And we're really excited. Probably in the next 6 months or so we'll have some some new results.

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Mark Kushner: So the physics, though. So that's all nice right, taking pretty pictures and and and looking at the data tracking the data. We've benchmarked a number of the of the pressures and the timing, but the like. I said, the physics is in the comparison of those high resolution data to our physics based models.

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Mark Kushner: And so here's some of the different aspects where we're trying to refine radiation transport. We think we have that under control. Understanding how our drive laser couple to the sample, and some of these other ones are ongoing and looking at strength effects, different transport properties of the material surrounding the void

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Mark Kushner: as well as as thermal transport. So this is a a way to understand void collapse. These are much larger scales than what we would anticipate for a nip if capsule. But if we can benchmark the physics using this kind of design, and we can move forward and do more complicated

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Mark Kushner: samples, such as multivoid. So how to voids interact with one another up to more than just 2 voids. Right now. You have many voids all the way out to a porous material. And what does that sound like? It sounds like a phone, and phones are one of the large and exciting candidates for a wide variety of fusion applications, inertial fusion, energy capsule materials, including wedded phones. So that's the direction we're going. Okay, and in order to do that again? I show this side slide, pulling it forward.

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Mark Kushner: You know there's a whole host of exciting imaging techniques x-ray imaging techniques that could take place at an X ray, free electron laser, or or or even here at at at Zoom, using back lighter technologies

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Mark Kushner: at a synchron. I think the the frontier is really rich, and exciting, and moving forward, leveraging novel optics, and X-ray imaging. So we're moving toward part of my goal in my portfolio at Slack is moving towards single shot, 3D imaging.

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Mark Kushner: So we take a phone. Let's say we take a wedded phone and we shot compressed, and I've designed a pinhole array that gives you more than just a stereographic view, but actually a multi dimensional view of the phone compressing out to hundreds of Gpa. Right? This is this is the direction we want to go to benchmark a number of the materials properties

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Mark Kushner: for me. Interest in in fusion energy. Okay. Now we're going to take a pivot, and we're going to talk about something quite a bit different and yet related. So

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Mark Kushner: I decided to combine my interest in material science in a shock compression, and this notion of void collapse. And I started thinking a lot about

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Mark Kushner: the origin of life, and it turns out that there are 3 sort of main hypotheses for origin of life, something called the Early Miller Experiment right, which is like lightning in a bottle. Lightning was able to ionize simple molecules, and then those molecules built up into something more complex.

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Mark Kushner: There's ha, ha! Hy hyper thermal extreme of file, materials or origin of life. We're at black smokers at the depth of our

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Mark Kushner: spreading ridge in the in the ocean. This unique environment of extreme Ph. High temperature, that organisms are able to evolve and flourish in those sorts of circumstances.

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Mark Kushner: And then there's the impact synthesis. And so this is something I started thinking about in the context of the novel capabilities coming online at Lcls and across the board.

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Mark Kushner: And the way I was starting to think of this is, you know, common elements in our in our solar system build up into more and more complex materials. So let's take the chawn right. The carbon, hydrogen, oxygen, nitrogen, and you know common molecules. We see in our solar system are listed here, and it turns out that they can come together. And really the the main piece here this side chain are is what dictates their functionality, and you can build up in different ways is complexity until you have

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Mark Kushner: the different nucleo bases, and then you get an Rna Strand and eventually a DNA strand. But there's something key here that the first 2 hypotheses you're a miller and hyper thermal extrema file synthesis, don't have and that's this notion of helicity or chirality

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Mark Kushner: in in the Rna Strand or in the DNA Strand, so of the 70 nucleobases that are possible in both Yuri Miller and the extreme of file hypothesis.

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Mark Kushner: The opportunity for designing right handed or left handed. Chirality in these systems is not well understood or not understood at all. And so I started thinking: what if the mineralogy of the host Rock? Okay, follow me here. What if

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Mark Kushner: these molecules, these simple materials, are hitching a ride on different vehicles and outer space, so called meteorites. Right? What if these simple materials they collide with one another right? We know that there's lots of collisions that take place even at the very small scale. Dust grains

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Mark Kushner: all the way up to meteorites, meteors, protoplanetaries, planets, moon, forming events right. There's a whole spectrum. And what if the Host rock actually matters in selecting the way in which this chirality evolves because

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Mark Kushner: of the 70 nucleobases, only 20 of which are used for life, and all of those have right-handed chirality.

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Mark Kushner: and nobody knows why. Right so I thought. I I wonder if there's something here where different prebiotic materials could be tested in a host rock like a meteorite or meteorite surrogate

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Mark Kushner: shock, compress. So you generate a plasma from that void or poor collapse that happens to be holding my prebiotic material. And then, you soft X-ray spectroscopy to watch the shot chemistry evolve from a simple material to a complex material.

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Mark Kushner: Well, is that possible. Well, it's possible. Have I completed it? No. So we haven't quite figured out all the pieces. But that's where we're going. So a note on this on this material templating. So biomimerology is actually a a really exciting, well studied area.

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Mark Kushner: But the opportunity for materials to polymerize on the surface of a of a mineral based on

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Mark Kushner: actually the structure and the the composition of that mineral is is it certainly an area of active investigation? So so synthesis of these different

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Mark Kushner: polymerizations and self assembly of the molecules on that surface might play a key role.

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Mark Kushner: So here are the 3 hypotheses that I already alluded to, and so we're going to look at a possibility of looking at amino acid formation during shock, compression of meteoric material in the presence of some sort of well qualified host fluid that is prebiotic.

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Mark Kushner: So, in order to do this, harkening back to my original days and Earth and planetary science, I was thinking a lot about meteorites, and you can think of meteorites as sort of the solar system Uber. But there's lots of mixing of material across our solar system, and there's a whole variety of of of meteorites.

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Mark Kushner: But the what I want to key point out to you is that we have the opportunity with certain minerals that we know are in meteorites that can give you this left or right handed chirality automatically. Right? So that's like that's fantastic.

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Mark Kushner: Okay. So there was a

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Mark Kushner: a study in 2,014 by this group. So Ferris at all in 2,014, and they looked at a material called Form of mine. Okay, so form of mind is pretty simple. Nh: Coh.

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Mark Kushner: Sort of a a run of the mail material. It turns out it's pretty abundant in interstellar dense clouds right? So there's lots of it out in the in the in the Cosmos effectively, and he orchestrated, or he and his group orchestrated an experiment to look at the the break up a form ofide into its an ionized components.

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Mark Kushner: and then formation of nucleobases. Right? So they did this on on a high intensity laser. And so my idea is to combine this approach. But in the presence of key minerals that could encourage templating at slightly longer at intermediate to longer time. Scales. Okay.

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Mark Kushner: So here's just a snapshot of what Ferris at all did. They had a a fairly high intensity Laser point for Terawatt, and they've got their form of mind in in a nitrogen bath.

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Mark Kushner: and they sent this laser through, and then they collected some spectra, and so they've got some different materials that they point out here, but the the temporal resolution we've learned from other

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Mark Kushner: biological studies at Lcos Chemistry studies looking at catalysis and the like. That. Actually, there's quite a bit of chemistry that takes place changes in the materials in the in the assemblies of these molecules it takes place on the Pico second time scale. Right? So just because

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Mark Kushner: we only have measurements of these timescales doesn't mean that there's there isn't more to learn. So i'm interested in what's happening. Pre 100 nanoseconds.

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Mark Kushner: Okay.

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Mark Kushner: So what I've decided to do in part of my portfolio with slack is to execute sort of an exobiology investigation, looking at Formamide and other prebiotic materials, and try to track that evolution. And i'm going to leverage some of these techniques that I've already shared with you diffraction. Right. I want to understand what's happening with the mineralogy of the meteorite or the host Rock material. I want to track the void collapse in that

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Mark Kushner: a silicate or titanium, titanium, rich alloy, or what have you? I want to look at? What is the interaction at that? At that interface between the form of mine or the prebiotic material and the Host rock.

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Mark Kushner: I want to execute spectroscopy. I want to look at the carbon edge, the nitrogen edge and the oxygen edge. Because that's where all that. That's where the money is. Right.

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Mark Kushner: This is the Holy Grail. Lots of x-ray free electron lasers, I should say lots. But there's a number of them that can get down to the oxygen or nitrogen edge, but it's hard to get down to the carbon edge. Oh, with Lcs 2 the superconducting. Linux we can do that. Moreover, we'll be able to do it at a megahertz.

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Mark Kushner: which is separate from my my drive laser, but I can build up statistics right? So I can actually see what I need to see. And then X-ray diffraction also tells me about what's happening overall.

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Mark Kushner: and the structure of my material. So this is a slide that talks about these. These experiments have not been executed. Proposals have been submitted

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Mark Kushner: to see if we're awarded bean time. I guess we'll hear in a few months if we are awarded bean time, but the opportunity to use x-ray emission, spectroscopy and and absorption spectroscopy to look at the chemistry, the changes

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Mark Kushner: in some of these, starting from form of mind, and and the breakup of that material, and then the complexation. How we build up, and something more complex, we'll hopefully take place. We will use what's called the Kemricks End station, so this is different than me, c. We Don't have a big laser there yet.

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Mark Kushner: but worry not. Other experiments have been

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Mark Kushner: executed in the past. This was some work done by Mcgregor, Sean Mcgrain, and other colleagues at Los Alamos national Lab, where we looked at energetic material and explosive material, which is also carbon, hydrogen, oxygen rich.

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Mark Kushner: and we were able to extract spectra to to track. How is this energetic material changing the shot chemistry as a function of time? Looking at the oxygen and nitrogen edges? So it's the same idea that I want to pursue, and we want to zoom in on the lower, on the early early time slices.

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Mark Kushner: Okay. So this is sort of a cartoon of what we envision, seeing I've got my meteorite that I've effectively soaked in form of I. So we are looking trying to isolate an individual, for in this material and look at the the the reaction that takes place.

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Mark Kushner: Okay. And then, beyond that, we want to bring in information, maybe a complimentary study that actually looks at the meteorite itself. We've done a lot of work. I've done a lot of work already on silicates. So this is a slide, speaking to the fact that we looked at

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Mark Kushner: shot, compressed Silica S. I. O. 2, which is a glass, but also courts, and we see that high pressure. Phases of courts form on a sub nanosecond time scale, or a few Nanosecond time scale. So that's interesting in and of itself

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Mark Kushner: bonds of the Si right. It's a it's a tetrahedral coordinated in in ambient condition. Courts have to break and reform into 6 full coordinated for stitch ofite. This is a high pressure. Polymorph. You see it at impact sites. You can actually look at it

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Mark Kushner: if you go to an impact site and pick up some material. Only 2% by volume is stitchabite. So not much forms, but we found that in situ there's actually quite a bit of Stitchovite, and we were able to start revamping some of the shock. Metamorphism stages that that frequently take place.

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Mark Kushner: So, understanding the the phase, transitions in the meteoric host Rock is important as well.

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Mark Kushner: And so we've covered a lot of territory here. I've taken you on a journey for 3 different case studies, and i'm gonna go ahead and conclude there. You know we've leveraged a number of really exciting techniques.

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Mark Kushner: I think the future is really bright for the next generation of scientists to come in and leverage these techniques to answer grand challenges in plasma, science in warm, dense matter and high energy density. Physics to say, you know.

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Mark Kushner: to to solve the the the problems of the future right, and it's up to you to to take these techniques and and improve and run with them. And today we've just talked about a few. But with that I certainly want to think

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Mark Kushner: a whole host of colleagues from a wide variety of national laboratories, different institutions, different academic institutions, my funding agencies. And with that i'm happy to take any questions. Thank you so much

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Mark Kushner: questions.

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Mark Kushner: It sounds elementary, I think it's mostly older people, and i'm not. But when you were talking with this shocked courts from media impacts. Yeah, okay, cool. I was. I was all lost there. Because yeah.

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Mark Kushner: I have a second question. So that's

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Mark Kushner: okay. Yeah, the courts. So so a lot of the materials in meteorites are silicate, based right lots of rich silicates, at least for chandritic material. Chandritic meteorites.

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Mark Kushner: Of course there are iron meteorites and stony iron meteorites that have a lot more iron in them, and you may be familiar with those they if you look at a cross section of those they have that beautiful Vidminstein pattern. Have you ever seen that it's the ex-solution of Malay in the in the iron meteorite. So there's there's different classes of meteorites. But for this work we're thinking more along the lines of what's called a palasite meteorite

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Mark Kushner: which might have some component iron iron nickel, as well as some silicate which my surrogate material here was just silica or or courts, which is just the S. I. O 2 and member.

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Mark Kushner: Yeah, can you talk a little bit more about this templating? How the chirality would be?

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Mark Kushner: No, not the material scientists, I. Yeah. So what's the physical mechanism? That's so? So so i'm not of a a an expert in in biomineralization. That's that it that is in itself a a whole discipline. But my understanding is that

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Mark Kushner: there are aspects of different bonds that are left available at the surface of that mineral, and that there's sort of different different termination sites

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Mark Kushner: at the surface of of a given, let's say, single crystal in this case is is a bit easier to understand, and that when the self, polymerization, or the self Assembly can take place just by virtue of sort of the the

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Mark Kushner: geography or the topography, if you will, of those bonds, and it appears to us as though there's some organization, right coordination when really it's just a a a principle of bonding in a in a certain order.

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Mark Kushner: And I think, what what has been proposed, though it's not. This is a hypothesis is that there are certain minerals, like Clays, for instance.

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Mark Kushner: where their termination bonds at the surface promote left-handed chirality in some of these more complex, whereas a titanium based but so titanium oxide, so called annotate, can promote a right handed

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Mark Kushner: and so separate test, not at extreme conditions, but just looking at that the

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Mark Kushner: steps. For this is called homo homo chirality bio homo chirality, where all life has only right-handed, so on and so forth.

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Mark Kushner: That's certainly an area of of active research and and that's not part of this but the static or ambient compression or ambient conditions is certainly a piece we need to investigate. Yeah

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Mark Kushner: back. Yeah.

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Mark Kushner: Great talk. Thank you. You mentioned something about phone being used in Nip. Could you explain a little further what that kind of concept with the idea is? Is it like

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Mark Kushner: It's kind of like

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Mark Kushner: I I don't know what what's the yeah. So so I think. And again, you probably have experts here in in your department far more than myself. But current capsules on the Nif essentially have a an ice mixture. Deuterium tritium ice mixture is their fuel inside.

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Mark Kushner: and I think the idea going forward is to capture some of this Dt in a phone sort of casing our environment, not only because there's a strategy there, maybe, in the microstructure and the performance.

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Mark Kushner: but it might be cheaper than having this

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Mark Kushner: beautiful Diamond Hdc. So they call it Hdc: because it sounds bad and publicity to say we're using dining. But anyway, so this Hdc. Right a later. Why, why, don't you have a plastic of blade or something? You could 3D print? I think that's the other direction. That phone where phones are attractive

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Mark Kushner: or different micro structures. Different materials besides diamond are attractive is the opportunity to 3D print, so you can mass produce quite a bit of this.

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Mark Kushner: There's also, you know, from a solid density material to a phone or something that has porosity.

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Mark Kushner: You track out different, essentially different Hugonio paths right based on the starting density. So there are some strategies in optimizing, you know, peak compression and the different pulse profiles of the niff. And again I default to folks who are more expert in in this than I am, but

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Mark Kushner: that's my understanding.

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Mark Kushner: I have a question about the imagery. So

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okay.

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Mark Kushner: So so how did you focus the X ripping, for example, at at 1880 S. Oh, G.

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Mark Kushner: It's a great question. So it turns out we have all sorts of tricks that we can use for focusing the X rays. I alluded to the fact that it 8 or 18 Kev. I can use a series of what are called compound refractive lenses.

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Mark Kushner: They're made out of beryllium. They're about the size of a nickel, and they have a really funny shape, so compound, refractive. They look like they look like a little bowl, right, but you stack them on their on their edge, and they're able to focus the x-rays and depending on how many I have. Let's say I have

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Mark Kushner: 15. Then I can focus to some, You know there's some focal length, and I can focus the 8 Kv. X rays. If I have 18 Kv. X. Rays that I need 40 or 50 of these beryllium lenses. Now, since

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Mark Kushner: everything started happening in Ukraine, which is a bummer, of course, the access, our ability to acquire quality beryllium, believe it or not, has really gone downhill, so we can't actually get new compound refractive lenses very challenging.

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Mark Kushner: So we've also been testing recently, for now zone plates, right? So this is back to sort of more traditional ways to to focus. And we've had actually quite a bit of success in delivering very smooth.

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Mark Kushner: clear, spatially reliable X-rays using the zone. Plate technology the problem is that with Lcls we have so many photons that if your zone plate is made out of gold or even platinum, all of your little zones, they start to melt after a while. So there's a lot of damage

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Mark Kushner: in order to overcome that we're designing at slack

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Mark Kushner: phase based not absorption based on place but phase-based zone plates using diamond so we're able to etch believe it or not. We're etching and designing novel structures and diamond to do this X-ray focusing?

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Yeah. sure.

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Mark Kushner: The question on your is contrast. Imaging, and I was just wondering if you're introducing a external pattern through some plate, or you're using a kind of inherent cycle pattern inside the material.

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Mark Kushner: That's a great question. The speckle that you saw in the images is unfortunately all coming from those darn beryllium compound. Reflect ref refractive lenses.

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Mark Kushner: So the the the changes in the illumination. We also know, even though we, I I claimed to you that we've got this fantastic, narrow bandwidth and high flux that actually there are different colors

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Mark Kushner: of the X-rays delivered through these lenses. So you actually see the breathing modes in that Focused X-ray spot. So some of that speckle is just due to this, this sort of interplay between the lenses and the way the pulses are delivered.

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Mark Kushner: Yeah.

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Mark Kushner: something way earlier in your talk you mentioned like seismic waves, or that there was research that showed side like seismic waves, faster and polar than equatorial. I guess the source of those are probably not the same.

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Mark Kushner: What's that?

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Mark Kushner: That's right? So the body waves that travel through the earth, so they're called P. Waves and S. Waves. So you have compressional waves and shear waves. and those move through the earth in a in a sort of periodic way.

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Mark Kushner: and seismologists have actually mapped out the structure of of our earth in in great detail, using those. And so that's actually how we found out we had a liquid outer core is those shear waves didn't move through that liquid outer course. Now cool. So back many, many decades ago, they realized. Oh, yeah, we liquid. Okay.

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Mark Kushner: I think it was in the twenties or something like that so the waves we feel on the surface are called Raleigh waves. So these are the ones that move us physically up and down in different seismometers can be sensitive to a certain sort of length scale at the surface versus body waves, and you can measure, You know, an earthquake in Japan, and we can record it over here by virtue of those body waves. Not necessarily the really waves.

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Mark Kushner: But i'm not a seismologist. So we should that result still apply to those types of ways.

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Mark Kushner: the results thinking about the structure of the inner core. What do you mean.

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Mark Kushner: I guess, like.

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Mark Kushner: you know. So they travel faster and different, like with an earthquake at the At a polar region d different in that way compared to

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Mark Kushner: Oh, I see what you're asking.

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Mark Kushner: I don't think so I think so. So If if a seismologist is just focused on the response of let's say the inner core.

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Mark Kushner: or because that's what i'm talking when I say they travel faster. I mean, we're only looking at that innermost solid in our core, and it doesn't actually matter. Where is the source? Where is the region where the event takes place, the seismic event

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Mark Kushner: the body waves will eventually propagate to the inner core, irrespective of their location, and they will still show that a body wave you can actually do. There's different line outs. They're called P. K. IP: I don't know there's this is a seismologist way of describing the different body waves.

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Mark Kushner: and they can track out, irrespective of that, that the longitudinal, the compressive wave, is faster by this 3 to 4, no matter what

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Mark Kushner: in the polar than in the equatorial. And that's weird.

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Mark Kushner: because you would assume, maybe naively, you would assume that it's just this nice polycrystalline inner court, where it's randomly oriented grains. But that's apparently not the case based on the seismic data.

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Mark Kushner: I was wondering if you had anything more to say on like being able to measure direct correlation.

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Mark Kushner: in the context of which

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Mark Kushner: I'm. A big advocate of

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Mark Kushner: recently. Now, with the development of all these unique tools, right

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Mark Kushner: of drilling down into what is the what are the physics models that we think we know

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Mark Kushner: that we're taking sort of for granted and comparing it the highest fidelity we can right. So if that's a a spatial fidelity, you know. Is it nanometers, or is microns enough?

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Mark Kushner: Is it a temporal fidelity? Do we need to be, you know, if your data is averaging over tens of picoseconds. But actually you need to be making a measurement at the one picosecond level.

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Mark Kushner: taking those data and and

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Mark Kushner: bringing it back to the physics model to say, Can I really trust this predictive, you know? Answer. Am I getting the right answer?

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Mark Kushner: Because I think it will surprise ourselves that we're we're generally close.

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Mark Kushner: But for some application spaces, whether it be, you know, work we're doing with industry or in basic science or in applied science, maybe in even in stockpile stewardship.

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Mark Kushner: the the

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Mark Kushner: stuff that we sort of gloss over, like all the correlation or the coupling my optical. I'm just going to assume it's like a factor of 2. But is that really right? Let's do our due diligence. Let's look in the data and vet it. And I think the only way we can do that is with higher fidelity. Data

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Mark Kushner: Speaker again.

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Okay.

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Mark Kushner: Okay.

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Mark Kushner: that's good.

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Mark Kushner: My

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Mark Kushner: My results have shown anything.