Emilio Nanni: yeah so thank you very much for the opportunity to come here today, at least, virtually and.
Emilio Nanni: You know present to you.
Emilio Nanni: Our concept cq to the cool copper collider.
Emilio Nanni: As a proposal really for an advanced future hicks factory.
Emilio Nanni: So this is a proposal and a concept that we've been exploring and developing with a great number of people and we've been doing this really over the last year, as part of the snowmass process in the United States.
Emilio Nanni: So, for those of you who might not be super familiar with it it's the Community study that occurs every 10 years or so, in high energy physics, you know really focused on.
Emilio Nanni: You know what what the US community is is trying to push for in the future.
Emilio Nanni: And we have three documents that we've submitted for cq that cover everything from the strategy, the R amp D plan that's needed over the next five to seven years.
Emilio Nanni: And the description of.
Emilio Nanni: The facility that we would like to eventually get to and built.
Emilio Nanni: And you can find those documents collected on this indiegogo site where you can also sign up for example to be on our mailing list if you want to follow.
Emilio Nanni: You know the activities that we're.
Emilio Nanni: taking part in, and you know and get updates on what we're pushing forward so thanks, of course, to all of the you know many people who have contributed to this.
Emilio Nanni: Okay, so what we're you know really trying to answer.
Emilio Nanni: As part of snowmass is what comes next for the energy frontier of course there's the great work that's ongoing at the lsc with with you know very exciting prospects in terms of.
Emilio Nanni: The high Leumi elysee upgrade that will happen and really Our question is what comes after that and there's a I think you know great excitement in the Community.
Emilio Nanni: For a future E plus C minus machine and there's lots of concepts that are in various stages of development and we'll cover those so i'll describe those in more detail later.
Emilio Nanni: And then use these is really a stepping stone to to future high energy machine.
Emilio Nanni: But from a physics perspective, really, what are we trying to do, and you know I think there's two things to highlight.
Emilio Nanni: For right after high low meal he and his in the first is establishing the color couplings to like flavor.
Emilio Nanni: and doing this with great precision and the second is establishing the self coupling of the higgs which really encouraged us to be able to push any E plus C minus machine up in energy.
Emilio Nanni: So y E plus C minus Next, I think this crowd probably is more than familiar with this, but it's easy to just see it very graphically if you compare.
Emilio Nanni: What happens in the detector of the collision point, for example in a PP machine like llc of course there's a great deal of effort that's involved in doing the reconstruction and if you compare that to eat plus or minus the environment is just much cleaner.
Emilio Nanni: The initial state as well defined, we can control the polarization of both the electron positron beam, and this can really lead to these high precision measurements.
Emilio Nanni: And then there are also advantages in terms of the design itself of the detector, for example, being able to work with trigger list readout or being able to do power pulsing so that we can have a better material budget in the detector for tracking.
Emilio Nanni: So these.
Emilio Nanni: You know, to let's say advantages, lead to a lot of excitement and interest for being able to study the higgs with an a plus C minus machine.
Emilio Nanni: So the next question really is what are the ideal energies for us to target.
Emilio Nanni: And if we consider his production of course there's a variety of mechanisms that could be studied and observed the lowest in energy that we are interested in as an initial stage for cq, of course, is 250 GB Center of mass.
Emilio Nanni: For ch production so looking at the peak in the cross section there for that, and as a second stage we really want to push above 500 GB.
Emilio Nanni: Where additional mechanisms, open up and, in particular, this one here the Z ah ah, so we can study the higgs self coupling.
Emilio Nanni: And this is a really important one, because it encourages us not only to go to 500 gv but the push up a little bit higher.
Emilio Nanni: So how can you do this generally you can categorize the accelerators that could reach these energies into two different categories, the first is linear colliders.
Emilio Nanni: concepts like i'll see cq and click.
Emilio Nanni: The advantage of a linear collider of courses that you can reach higher an energy and principal up to a few TV is relatively straightforward, although you have to be continued to extend the site length in order to do that.
Emilio Nanni: And second of all you have to include you can include polarization of both the electron and positron be.
Emilio Nanni: also want to say briefly Before I continue, if people have questions i'm always happy to to answer them as we're going along or at the end of the talk.
Emilio Nanni: So the other, you know big benefits relatively low radiation from the beams as they're being accelerated because they're going in a linear direction, and so we don't have problems with synchrotron radiation.
Emilio Nanni: And the second is or the final one here really is that collision and bunch trains, so you can do things like powerful cinema detector.
Emilio Nanni: Of course this does bring up some complexity in terms of the bunch spacing between the bunches which can be fairly close within that that bunch train and that's something that has to be accounted for in the detector.
Emilio Nanni: The second category really is circular machines examples like FCC or CPC and these really have the advantage of very high luminosity in particular low in energy, but they do struggle, as you get higher in energy and can have very, very high power requirements.
Emilio Nanni: Especially if you want to get to 350 400 gv and going much beyond that really is a big challenge.
Emilio Nanni: Of course, the beam continues to circulate after the collision and this is what drives up the luminosity of these facilities.
Emilio Nanni: So there's a you know a lot of different proposals out there, I think the most advanced in terms of technical readiness, everyone would agree, is the international linear collider which was proposed for a sighting in Japan, this is a machine that's based off of superconducting rf technology.
Emilio Nanni: The other leading you know candidate that has significant development for linear colliders, of course, is click as well, and which is a normal conducting machine that uses a second accelerated being to drive.
Emilio Nanni: The beam that will be used for collisions.
Emilio Nanni: And then we have cq which will really be the focus of the rest of the talk and we think this is a an exciting possibility and concepts to bring to the table.
Emilio Nanni: One that has some real advantages in terms of being able to be built in a compact footprint get to energies that are of great interest now and provide a pathway for getting too much higher energy longer term so really opening up I think an exciting physics program for for the Community.
Emilio Nanni: So before we really get into the details about cq, I would like to say just a couple more words.
Emilio Nanni: about why 550 GB for a second stage so we're proposing to start at 250 GB Center of mass and one of the really unique features of cq is that we can do our first energy upgrade without changing anything about the site length.
Emilio Nanni: So the site length that we're proposing at the moment is right at eight kilometers although i'll discuss a slightly shorter option.
Emilio Nanni: And what we would do is, we would first operate at a lower accelerating gradient get to 250 GB Center of mass and then we would add additional rf sources to push the gradient up in the main Linux and get to 550 GB Center of mess so wi fi.
Emilio Nanni: Of course, you know, having an orthogonal data set would be really.
Emilio Nanni: Important if we see any deviations from the standard model.
Emilio Nanni: But you know also it allows us to study, for example, the topic of a coupling and if we just go from 500 to 550 we get a factor of two improvement.
Emilio Nanni: In terms of measuring that coupling which would be really interesting.
Emilio Nanni: The beam parameters that we are targeting really are aimed at delivering the same luminosity and the same precision.
Emilio Nanni: That would be achievable with the IOC and so getting this additional boost in energy would be really great for the physics community and then finally allows you to study the precision with precision, the himself coupling.
Emilio Nanni: which would be, of course, a great interest as well.
Emilio Nanni: So let's take a look really at the cq and you know why it's novel route towards a linear E plus or minus collider.
Emilio Nanni: So the origins of cq really come from.
Emilio Nanni: revisiting the design and approach for rf accelerators and it started, you know it's really a development that's been worked on over the last 10 to 15 years focused on understanding how we can optimize.
Emilio Nanni: The design of cavities and how we can push them to work well at very high accelerating gradients so that they're both efficient and allow for us to reduce the size of or the footprint of any major accelerator.
Emilio Nanni: And what you do is you start by looking at a cavity and you say i'm going to optimize it so that it's as efficient as possible for accelerating the beam.
Emilio Nanni: And what you get are these nice reentry shapes with these tailored profiles to keep the surface electric and magnetic fields down and i'll discuss a little bit more why that's important later.
Emilio Nanni: But the problem that you quickly realize is when you have this type of cavity shape with this relatively small aperture and these re entering those cones.
Emilio Nanni: You don't get any cell to cell coupling so there's no rf coupling between any of these adjacent cavities.
Emilio Nanni: And that's great from a design perspective because it allows you to optimize the cavity and have any phase advanced that you want, so you can maximize the acceleration.
Emilio Nanni: But it's a problem because, how do you get rf power into this Linux on a typical approach, for example, next Center collider i'll see click our power is actually flowing down in the same direction as the electron be.
Emilio Nanni: So the solution to that is this approach that's called distributed coupling where you have to have rf coupling to each cavity individually and you need to do it in a way that is economical and allows for you to not perturb the performance of each of these cavities.
Emilio Nanni: And this is actually relatively old idea, but its implementation couldn't really be done until recently.
Emilio Nanni: Because there's cross coupling through the waves guide in all from all of these cavities and so you really need very.
Emilio Nanni: Advanced simulation tools and a lot of computing power in order to come up with this design that you're seeing here.
Emilio Nanni: So what we're looking at is a distributed coupling accelerator each cell is optimized individually, the power that is needed for each of these cavities flows down these wave guides.
Emilio Nanni: And we see the electric field that is established in each of the cavities here the color alternates because the fields are an opposite directions and it flips when the electron bunch arrives in the next cavity.
Emilio Nanni: So you combine this together, and you get these really efficient designs and you optimize for what we call shunt impedance but it's really just a measure of how efficient.
Emilio Nanni: The structure is in establishing the fields that are used to accelerate the beam so it's the gradient squared divided by the power that's dissipated in the Linux.
Emilio Nanni: And you have to do this while controlling the peak surface electric and magnetic fields, because otherwise the problem that you run into.
Emilio Nanni: Is when you go to very high accelerating gradients you get an Arc you get a plasma that forms this referred to as a breakdown and when you have a breakdown in the accelerator.
Emilio Nanni: That disrupts your being so if you have too many breakdowns in in the operation of the clinic you would degrade the luminosity of the facility.
Emilio Nanni: So this you know style of design and controlling these fields it's really The key to this hydrating operation in an efficient way.
Emilio Nanni: The other innovation that we're really bringing to the table is operating these accelerating structures that are normal conducting but doing it at cryogenic temperatures.
Emilio Nanni: So the motivation for doing this was a study that was focused on reducing the occurrence of these breakdowns are these Arc parking events in these accelerating structures.
Emilio Nanni: That observed that, as you increase the material strength so as you go from soft copper, so this is just a kneeled copper copper that's been through a thermal cycle.
Emilio Nanni: To, for example, a copper alway like copper silver, which has a higher yield strength, you get significantly improved performance in terms of when breakdowns occur.
Emilio Nanni: And so it was proposed that well why don't we go to lower temperature and see how these same accelerating cavities behave and there were this first group of experiments that were done at 45 degrees kelvin.
Emilio Nanni: And they showed really this you know breakaway performance, an additional 50 megabits per meter before any onset of a breakout, so this is really you know big delta in terms of performance.
Emilio Nanni: And you know something that would allow us to push the gradient up even higher, it also.
Emilio Nanni: Really reduces the amount of rf power that you need it makes the structure more efficient from a shutdown peanuts perspective.
Emilio Nanni: Which is really attractive because rf power is the cost driver for a normal conducting accelerator, so those two benefits really seemed to make it an exciting option.
Emilio Nanni: Now for our case we're actually going to operate at 77 seven excuse me 77 kelvin.
Emilio Nanni: The temperature of liquid nitrogen for the mainland and because it's very economical it's very simple to work with.
Emilio Nanni: large scale production is available, you can have prior plants, no problem, it has a large heat capacity so it's great for cooling it's just extremely simple to handle.
Emilio Nanni: We don't have to change any of the fabrication processes that we've developed for the for the mainland neck, this is an example of a distributed computing distributed coupling accelerating structure.
Emilio Nanni: That we had actually built for room temperature operation, but everything to all of its properties that were necessary for acceleration when we cool it down to liquid nitrogen temperature.
Emilio Nanni: And this was actually really the first test that we did with this immersion and liquid nitrogen for one of these structures.
Emilio Nanni: You do have to also be concerned about the impact on the overall electrical efficiency as well, but the picture is not too bad there.
Emilio Nanni: So one concern is that the efficiency of the cryo plant is only about 15%, so this is because of carno and additional losses in the system so removing heat from the main Linux at 77 Calvin does cost you in terms of the electrical efficiency compared to being at room temperature.
Emilio Nanni: However, as I mentioned the structure becomes much more efficient, so the amount of rf power that you need to deposit into the structure.
Emilio Nanni: goes down by a factor of two and a half, so this is a big boost in terms of the efficiency, because we're not losing that power at 77 K.
Emilio Nanni: The other thing that you have to factor in is also the efficiency of the rf source, so the efficiency of establishing this rfp or creating this earth power in the first place.
Emilio Nanni: And that's about 50% for these art sources so combine these three things and we come out to about 75% as efficient if you ran this accelerating structure at room temperature, at the same gradient.
Emilio Nanni: So we do take a hit in terms of electrical power for the main leg but it's something that's definitely manageable.
Emilio Nanni: So we take these two ideas together and combine them distributed coupling plus operation and cryogenic temperature.
Emilio Nanni: And we started to think about how can we can you know develop an accelerator complex around this and that's really what the cool copper collider is.
Emilio Nanni: So here's an example of one of the meter scale prototypes that we have built for this accelerating structure.
Emilio Nanni: they're very simple to manufacturer compared to the conventional approach, which involves one to two pieces per cavity were able to do this with two slabs of copper that are machine down a cnc.
Emilio Nanni: The cost actually have the machine that you see in this picture is equal to the material cost, which is just sort of very unusual when you're talking about the fabrication of accelerating stripes.
Emilio Nanni: We would operate these structures at 77 kelvin we've done experiments up to very high gradients hundred 50 megawatts for meter.
Emilio Nanni: and accelerated been through these types of structures and we're now testing, what we really see as structures that are.
Emilio Nanni: You know prototypes for a main Linux for linear collider the one that you see up here, this is the structure in higher power test we've done room temperature high power test was these meters scale structures and we're preparing to do cryogenic ones.
Emilio Nanni: As a follow up to it.
Emilio Nanni: Now we've taken these structures up to 150 megabits per meter, but we are planning on operating them in our present proposals up to 120 megabytes per meter this is really just the you know cost optimize point for the main Linux.
Emilio Nanni: But as i'll describe here in a bit, but actually start at a lower gradient now very important to note that this approach is something that's scalable to the Multi TV range.
Emilio Nanni: Because with this gradient we can still achieve these higher energies in a compact footprint.
Emilio Nanni: Okay, so.
Chris Damerell: Sorry, to button amelia Could I just ask.
Chris Damerell: For those who don't know, I have to know the answer to this one, but those two half structures that you shown, could you say a little bit about the magic how you put them together.
Emilio Nanni: Oh great great question.
Emilio Nanni: So.
Emilio Nanni: The way that they're bonded for our prototype structures at the moment.
Emilio Nanni: Is we put a copper gold raise.
Emilio Nanni: alloy, which is actually a laser cut Shin so it's about 25 to 50 microns thick depends on how we're doing the the bond.
Emilio Nanni: But we put this foil it's laser cut to match the shape that goes around the outside here.
Emilio Nanni: Then we stack the two plates, together with these alignment pins.
Emilio Nanni: To make sure that the structure is aligned, we can actually cold test it and inspect it when it's stacked and make any corrections that are needed.
Emilio Nanni: If that's the case, and then we put this in a hydrogen brace furnace so it's really you go up in temperature to about 1000 degrees C and the environment, that it is in is hydrogen gas.
Emilio Nanni: The reason we like to have hydrogen is it reacts with any impurities that might be on the surface and it makes hydrocarbons that burn away.
Emilio Nanni: And what you end up with is really, really clean copper surfaces and there's a lot of hydrogen that gets absorbed basically into the copper structure.
Emilio Nanni: Then, when you go under, you HIV conditions and high temperature the hydrogen out gases, but it outcasts is very, very well and eventually you end up with a very clean copper material.
Emilio Nanni: That has been bonded together, because that copper gold foil here what happens is it has a lower melting point than copper, so it melts the gold the fuses into the bulk of copper and then it freezes and that way you get a really nice joint.
Emilio Nanni: Thanks Chris.
Emilio Nanni: Okay, so we have this accelerating structure and how do we actually go about doing the design for it.
Emilio Nanni: Well, from the perspective of the accelerator, is what I need to know is the the bunch of charge and the being power that we need to put.
Emilio Nanni: Through these types of structures and what you can see in these two plots on the right is there's a really close correlation between luminosity that you can you can achieve either with IOC or click.
Emilio Nanni: And the amount of being power that you need to put through the accelerating structure, so we we you know basically pick this right here, right above to megawatts in terms of the mean power that we wanted to put through the main Linux at 250 gv Center mass.
Emilio Nanni: And then, for a bunch of charge we're working with one nano cool am at the moment because that's kind of in the range of click and the nlc proposal so that we know we can achieve you know luminosity that's that's exciting.
Emilio Nanni: Some other details in terms of the main Linux design we're actually working a little bit lower frequency 5.7 gigahertz.
Emilio Nanni: we're doing this because there's more commercially available technology for the rf sources, the aperture that we have is really comparable to click and it's driven by the Wakefield considerations that we have.
Emilio Nanni: We have a significantly larger bunch spacing then then click an llc, which is a bit of an advantage for us.
Emilio Nanni: And then the number of bunches that we have in any bunch train in our initial phase, would be 133 and then we reduce it if we do an energy upgrade and i'd be happy to explain why people are curious.
Emilio Nanni: So let's you know, take a look, then at what the accelerator complex itself would look like so we're targeting that has something that has an eight kilometer footprint, this is both for 250 and 550 GB Center of mass.
Emilio Nanni: The gradient would start out at 70 mega volts per meter and then would go up to 120 mega volts for me to to get us to this energy here.
Emilio Nanni: You can see what the site layout looks like and pure and black, you have the main Linux themselves and in green, you have the beam delivery system.
Emilio Nanni: So large portions of this complex when we do our studies are really adopted from other linear collider approaches because there's a great deal of synergy so, for example, the beam delivery system, the studies that we've done.
Emilio Nanni: really start from the beam delivery that's used for IOC slightly modified so that it would work for 250 and 550 GB Center of mass.
Emilio Nanni: The damping rings and injectors we use those for click as a baseline and then what we've done is we've actually used the.
Emilio Nanni: costing studies from other linear colliders modified effectively by our main Linux in order to optimize the overall footprint and size of the complex and to pick the accelerator ingredients that we need in order to achieve a beam power which would deliver a luminosity of 10 to 34.
Emilio Nanni: So I you know what one thing that I want to stress here personally is that if if you can compare this, for example to other.
Emilio Nanni: linear collider approaches what you see is that the main Linux which for other linear colliders is really the dominant.
Emilio Nanni: source of cost in the system source of complexity in the system for us that's no longer the case.
Emilio Nanni: The beam delivery is is is you know really have the same magnitude as the main lynette and the injector complexes is the same magnitude is the main clinic and I think this really affords us a very exciting opportunity to take a look at these other systems and more detail.
Emilio Nanni: I really asked how they could be optimized further and make you know, realizing such a complex more more practical so i'll give you one example.
Emilio Nanni: So for the the electron source, what if you had a high brightness polarized rf gun instead of a DC gun that had to go through a dampener this can actually have a huge impact on the overall complexity and requirements for the main Linux.
Emilio Nanni: Other example, could be what if you can make a more compact or a.
Emilio Nanni: Simpler beams delivery system, this could also have a very big impact, so it really opens up the the you know the whole complex in order to in terms of making improvements so so we're really.
Emilio Nanni: I think that's the next phase for us is starting to look at the whole site and seeing how we can optimize it for cq in in a better way.
Emilio Nanni: So let's do a bit of a direct comparison between the different concepts.
Emilio Nanni: And we've got a couple of things here that are highlighted that i'll focus in on.
Emilio Nanni: So one of the key differences, of course, is the accelerating gradient, this is what allows us to have a compact footprint, so we start out at 70 megabytes per meter.
Emilio Nanni: and eventually we're planning on bumping up to 120.
Emilio Nanni: Let me just jump back one slide it and I think I forgot to mention this, we do have an option, where we would go to a seven kilometer footprint by by boosting the gradient further.
Emilio Nanni: This is really driven by like site constraints, so, for example, if you wanted to put this on the fermilab site and still get to 550 GB Center of mass, this is what he would do, but it would drive up your rf power requirements, and it would make the system more expensive overall.
Emilio Nanni: However, you know if if you can't go outside of the fences is something that you could certainly consider doing.
Emilio Nanni: You don't I should also add need to change the gradient for the 250 GB Center of mess to do this there's a lot of spare capacity in the eight kilometers for the initial stage.
Emilio Nanni: Okay, so we have a gradient of 70 and 120 megawatts for meter The other thing that's really important is the actual real estate gradient so there's the gradient and the accelerating structures themselves, but what about all the stuff that goes in between those accelerating structures.
Emilio Nanni: So cq because it's cool than liquid nitrogen were able to have a very, very high field factor, the crime modules are very simple the interfaces between the Crown modules would be you know very straightforward so we're targeting close to a 90% fill factor for the Mayo clinic.
Emilio Nanni: So, in terms of effective or real estate gradient we're around 60 megabits per meter and then eventually hundred and eight, and this, for example, stands in stark contrast to the IOC where your effective gradient is really 2020 megabits per meter so.
Emilio Nanni: And then the site footprint, this is what makes it so compact, the high gradient and eight kilometers we can do both to 50 and 550 GB Center unless.
Emilio Nanni: Of course, you know we're really at the pre cdr stage and and a lot more development has done has been done for click and I.
Emilio Nanni: So let's look a little bit more at the beam format.
Emilio Nanni: And how it would impact the detector.
Emilio Nanni: So.
Emilio Nanni: You know just for comparison you know what's the IOC timing structure.
Emilio Nanni: They have no millisecond long bunch trains that are repeated at five hertz there's a couple thousand bunches are trained and there's each bunch each electron bunch each positron bunch is spaced by 300 nanoseconds.
Emilio Nanni: So we have a fairly different structure we operate at 120 hertz.
Emilio Nanni: With 133 one nano cool and bunches and the first stage, and those are separated by five nano seconds each so, how does this, you know, really.
Emilio Nanni: affect the the detector designs So the first thing is, we still can do things like powerful thing, so the detectors would be off in between bunch trains.
Emilio Nanni: This would reduce the heat load and we'll let you have a better feel factor for.
Emilio Nanni: The.
Emilio Nanni: detector itself we don't need active cooling so for you in, for example in the tracking and this you know improves the material budget for.
Emilio Nanni: The detectors themselves, and we would still operate, for example, with a trigger this trigger less freedom.
Emilio Nanni: Now the backgrounds, that we would have because they have a slightly different bunch structure would be different than i'll see your click.
Emilio Nanni: But we've started talking to some of the detector groups, and this is definitely an area where we would like more input and more interest from the Community, but we do think that the timing structure is compatible with something like an si T detector.
Emilio Nanni: But we really need to do more, design and optimizations with with respect to this.
Emilio Nanni: Okay, so let's take a look at you know what's the overall timeline that we could target from a technical perspective for realizing this accelerator complex.
Emilio Nanni: Taking into account a couple of things early on in terms of the you know the http planning process in the in the United States.
Emilio Nanni: So what we're working on right now, are our submissions to snowmass and we're starting to prepare a proposal for a demonstration facility that would mature the technology enough to answer the questions that we need for a cdr.
Emilio Nanni: That demonstration RD program would take about five to seven years.
Emilio Nanni: During that time, we would also be working on a cdr and towards the end of it, we would switch over to preparing a TD, are at the end of the demonstration phase, we would switch over to industrializing the technology that we have developed.
Emilio Nanni: This is something that really you know would be you know industry would be partnered with us throughout the demonstration phase.
Emilio Nanni: But this is where they would ramp up in terms of the amount of production that they could do.
Emilio Nanni: Construction for the facility itself, but if we do an underground site would take in the range of eight to 10 years.
Emilio Nanni: we'd have one year for commissioning of the accelerator complex and our goal is to have physics by 2040 where we would do a decade of running at 250 gv Center of mass during the downtime for the machine, we would be installing additional rf sources in the main Linux.
Emilio Nanni: And then, at the end of our run for 250 GB Center of mass we would increase the accelerating gradient and operated 450 GB fixed up at 550 GB surface now, if you want to take this same technology to a few TV.
Emilio Nanni: that's definitely an option, but you have increased the mainland excellent.
Emilio Nanni: Okay So where are we in terms of our R amp D efforts today at the moment we're really focused on the structure development, making the process more robust and proving that the designs, we have for the mainland at work.
Emilio Nanni: At the gradients that we need them to.
Emilio Nanni: So we have rf design stead have the distributed coupling and have the low peak surface electric and magnetic fields.
Emilio Nanni: we're working on the actual production of these types of structures, as I mentioned before, you can see here in yellow that's the copper gold brace alway.
Emilio Nanni: we're happy with this approach, it works it delivers what we need, but we're also looking at some other options which might be more favorable in terms of mass production.
Emilio Nanni: So, for example, electron beam welding around the outside is one very interesting approach or doing basically a hybrid of bracing and diffusion bonding which would allow you to do this at lower temperature faster.
Emilio Nanni: And then finally we're doing actual structure testing so everything from single cavities to meter long structures.
Emilio Nanni: And here, in particular, it shows some experiments that were collaborating with Los Alamos national lab on.
Emilio Nanni: That are testing single cavity structures, and these have done extremely well they've been able to get to very, very high gradients even beyond 150 megabits per meter so we're very excited about those results and there'll be.
Emilio Nanni: submitted for review very soon.
Emilio Nanni: So beyond actual prototyping of the structures we're also starting to look at how you would incorporate these into the cryo module where the structures would be immersed in liquid nitrogen.
Emilio Nanni: And how we would do the alignment that is needed for the accelerating structures and the components that are at such a low temperature, so our idea is to have individual cry modules that are about nine meters in length.
Emilio Nanni: The crime module would be able to accelerate up to one GB per cry module with this 90% phil factor so there's eight one meter structures and the crime module.
Emilio Nanni: And every two structures there's separated by a tenable permanent magnetic quad.
Emilio Nanni: This alignment that we need in the mainland Eric is around five microns, and this would be a combination of two stages first you would do mechanical alignment.
Emilio Nanni: For routing temperature.
Emilio Nanni: Then you do mechanical alignment at liquid nitrogen temperatures at 77 kelvin and then, finally, you would have active being based alignment with us electric motors.
Emilio Nanni: And yeah we're we're really starting to look at how this would be put together how the structures would be supported on rafts where we would put, for example, the alignment.
Emilio Nanni: Reference features we're thinking of doing wire alignment initially for the mechanicals stage and then turning over to being based feedback with bpm monitors inside of the quads.
Emilio Nanni: In order to get down to this five micron level.
Emilio Nanni: So we're also thinking a little bit about how this would actually fit together in a tunnel, and you know kind of fit into the types of tunnels that have been considered for other.
Emilio Nanni: linear collider designs so over here on the Left you're seeing the rf sources that would be required for that initial stage so for 630 me the.
Emilio Nanni: Acceleration per nine meter crime module and what you need or four of these high power art class trends, they put power on to these two wave guides in each class tron powers to one meter accelerating structures.
Emilio Nanni: And over here on the right, you can see that it does all fit into a tunnel that has the same inner diameter as what's being considered for i'll see.
Emilio Nanni: So we have the separation wall here's the main Linux, this is the one that's actually installed.
Emilio Nanni: there's room for transport here's our source that's installed and still plenty of room for transport as well with all of the ancillary stuff fitting in very comfortably.
Emilio Nanni: So we're going to look at this and see if we can do do it with a smaller tunnel, but certainly you know there's lots of tunnel boring machines, they can produce tunnels in this range.
Emilio Nanni: So you know when we talk about the scalability.
Emilio Nanni: Of this approach, you know and why it works from 250 GB to a couple of TV, the reason we feel that way is because we actually originally did the design optimized for to TV Center of S.
Emilio Nanni: collider and so that that's kind of baked into the way that the mainland would come together and how we would do the cooling.
Emilio Nanni: we've actually demonstrated the full thermal load that would be put on to the mainland act in a structure that was a quarter of a meter.
Emilio Nanni: You can see the cooling here, so this would be roughly the level of the liquid nitrogen in the cryogenic vessel.
Emilio Nanni: The cryogenic vessel is very simple, the same space that has liquid nitrogen has the nitrogen gas and there's no active pumping and there's just one layer of.
Emilio Nanni: You know vacuum jacketed instil installation, which is the standard for really any door that you have here, many of you i'm sure having your labs.
Emilio Nanni: From the larger scale perspective, what we do is, we would have one cryo plant that would be located.
Emilio Nanni: Every kilometer or so the cooling capacity of the plant has 1.25 megawatts at at Calvin.
Emilio Nanni: It would liquefy about seven liters per second of nitrogen that gets inserted into the crime module and it it just flows thanks to gravity and replaces the liquid that's been that has evaporated and it is being pumped out and returned to the crapper.
Emilio Nanni: This would then repeat until the length that was needed for.
Emilio Nanni: You know the collider that you're building so, for example.
Emilio Nanni: If you wanted to do something that was around two TV Center of mass you would do nine of these excuse me 10 of these segments and it'd be roughly 10 kilometers per mainland.
Emilio Nanni: So what about power consumption, of course, this is a big question and i'll just talk about it for for one of the cases so for 250 GB Center of mass and tend to the 34 luminosity we would need about 100 megawatts for.
Emilio Nanni: The main Linux in terms of electrical power.
Emilio Nanni: And an additional 50 megawatts or so, for the rest of the accelerator complex, so the site power that we need for 250 GB Center of mass is 150 megawatts.
Emilio Nanni: It only goes up to about 175 megawatts when we go to 550 GB Center of mess, because we change the pulse structure that we use so we make the our flat have shorter in order to do that and i'd be happy to explain that in more detail if people are interested.
Emilio Nanni: So uh I do want to say a couple words about our sources, the rf sources are really a very important topic for us.
Emilio Nanni: As you can see, on this plot actually why we did our design, starting at 70 mega volts for meter So if you look at what what it costs in terms of our source power, the clip case study go gives this range here for commercial sources that are available today.
Emilio Nanni: And what you see is, if you look at the overall main Linux using our approach the gradient that you'd like to operate, that would be sort of in the 60 to 80 megabytes for me to arrange.
Emilio Nanni: For this cost and it's only if you can push the cost down that your cost optimize gradient goes up 220 megabits per meter so I don't know for our initial stage, we want to start here, because this really would be the cheapest option for the mainland.
Emilio Nanni: But there's been a lot of progress that's been done in the rf source community over the last.
Emilio Nanni: 10 years or so and it says something that's been a focus for the US Community through the doa guard program for search through the haiku collaboration and there's a lot of people that are working on pushing this cost metric.
Emilio Nanni: down so we're hoping to take advantage of that.
Emilio Nanni: When we do the upgrade to 550 GB once again that's not a requirement, but it does make the the upgrade itself cheaper if we can achieve it.
Emilio Nanni: So where are we today, I mean the sources that we need are available so here's an example of one installed at Los Alamos when we used to power cavities it's definitely you know, we have the technology today to build a me Linux.
Emilio Nanni: But there's a lot of great development that's been done so, for example, with these two approaches once called core isolation method what's called punch line compress.
Emilio Nanni: And they've been prototypes that have been built this really boosts both the powers that you can get as well as the efficiencies that you get out and they look very appealing, so you can make lower voltage lower current sources that could be.
Emilio Nanni: less expensive industry has started to adopt these little bit lower in power than we need so in the 20 megawatt range but they're starting to transition over an hour free to this talk by Igor which is really a lot of great examples of the work that's done.
Emilio Nanni: And and one design, in particular, that he discusses in that presentation is really one that would make a huge difference for us so, for example, this is a 50 megawatt class.
Emilio Nanni: rf source and you see that the efficiency, using some of these new techniques for the class tron.
Emilio Nanni: pushes the the the efficiency from 36% to 69% I mean just a really big jump and something that for us, would be very important, because it drives the cost of everything that's upstream of that way down.
Emilio Nanni: Okay.
Emilio Nanni: Just a couple of words, also about you know what the other kind of technical area that we're focused on right now and that's incorporating wakefield's depression in the accelerating structure we do require both damping and D tuning.
Emilio Nanni: In our accelerators and working on doing that, with this slide Deming approach.
Emilio Nanni: On go a little bit fast here because.
Emilio Nanni: I want to leave some time for questions suffice it to say that we think we have an rf design, which works it gets the key factor low enough and we're working on prototypes.
Emilio Nanni: For how to to test this and we need to scale it up to one meter, so this is something I would have been kind of very early on in our demonstration RD plan.
Emilio Nanni: So let's talk a little bit about that in terms of outlook So what do we, what do we really need to do in order to prove the Community that this is feasible.
Emilio Nanni: And you know what we keep coming back to is demonstrate the operation of a fully engineered crime module we think this would take at least three crime modules stacked together.
Emilio Nanni: so that we could test the full liquid and gas flow rate and i'll describe a little bit of how we would do that and the next slide we would need to test this.
Emilio Nanni: hat and above the full accelerate ingredient for see cute.
Emilio Nanni: And you know do that with these fully damped in detail structures, so you know no additional R amp D needed for the accelerator, the main lynette component itself at the conclusion of the demonstration face would really be something that could go into production.
Emilio Nanni: And this would be something that I think would have a lot of impact outside of http as well it's something that could be used for contact fields for studying been dynamics for making high brightness guns.
Emilio Nanni: So there's a lot of lot of reasons to do, how to get the Community excited about doing this.
Emilio Nanni: So one of the documents that we've posted.
Emilio Nanni: On that indigo and submitted to snowmass describes that demonstration plan in detail.
Emilio Nanni: So we're really here today and stage zero kind of with the work that we're doing at the prototype level.
Emilio Nanni: we're starting to transition already into Stage one we're thinking about how the demonstration facility would come together, and this is really the kind of five year period that's needed to link up these crime modules and put been through them, and here you can see many applications.
Emilio Nanni: Beyond high energy physics, that I think will get you know will broaden the appeal of this approach and get a lot of Community support.
Emilio Nanni: outside of ATP.
Emilio Nanni: So, also a little bit of an advertisement I know there's a great deal of work that needs to be done and we're definitely looking.
Emilio Nanni: For for people to to help out both on the accelerator side on the detector side of physics side, so please do reach out, you know we're encouraging everyone from from really experts in the field to early career scientists to get involved.
Emilio Nanni: You know we're trying to build the collaboration that would would allow us to carry this forward for for many years, so if any of these topics are interesting beam dynamics vibrations cryogenic controls detectors please reach out and we're excited to have you involved.
Emilio Nanni: So in this view graph you can actually see what would what would come out of this demonstration plan it's a it's a facility that would be roughly 50 meters long, it would have an injector that would be able to produce a beam.
Emilio Nanni: That would match the full beam loading characteristics for the main Linux here we have three cry modules and then this is the fun part, so we want to test the cry module with the full flow rate for the liquid nitrogen so seven liters per second.
Emilio Nanni: which actually in terms of velocity is quite slow.
Emilio Nanni: But it's a lot of a lot of volume for both the liquid and the gas, and you know typically or the proposal would be that there would be 500 meters of of accelerating structure.
Emilio Nanni: That would be producing the thermal load that you need to require that amount of cooling So how do we get around that and just just you know facility, where there's 30 meters of clinic.
Emilio Nanni: way, we would do that is by having a heater so a liquid nitrogen boiler at the end of these crime modules.
Emilio Nanni: That could you know put in a thermal load let's say even up to a megawatt and evaporate a lot of liquid nitrogen.
Emilio Nanni: And we would need a liquid nitrogen tank so the liquid nitrogen tank would replace any of the liquid that was evaporated and the gas return and would vent out so this little region here this this.
Emilio Nanni: You know insertion and attraction region would really be the same thing that you would have in the mainland.
Emilio Nanni: And this crime module in particular would would would see the same effects that you would expect, for the crime module that has the highest volume of liquid and gas flowing through it.
Emilio Nanni: So that would really allow us to test the main Linux in its actual condition so full gradient full cryogenic flow and full being parameters.
Emilio Nanni: Okay, so you know we're working on our next cq workshop there's a link to the to this Google form if you're interested in participating, you will be hybrid.
Emilio Nanni: So will be on site at fermilab but remote options will be available, so please, please do fill this out if you're interested and or you can sign up here for email list and there'll be more information coming up on that.
Emilio Nanni: Just in conclusion, you know cq we think it's really a rapid route to studying physics physics.
Emilio Nanni: it's a compact facility eight kilometers, this is a goal for us X physics by 2040 possibly even a US hosted facility, you know here, this is produced by our colleagues at fermilab and with the seven kilometer version.
Emilio Nanni: But you can see that it's you know it's something that can be realized.
Emilio Nanni: Within the footprint of a national lab.
Emilio Nanni: You know, we need, we need to do more work also not only on the accelerator complex but on detectors and that upgrade to 550 really is a I think a unique.
Emilio Nanni: feature, and one that could lead to you know, a couple decades of really exciting science for this facility.
Emilio Nanni: And just one last comment you know we've we've talked a little bit about doing a gig as a run at 91 Jeff.
Emilio Nanni: In the past, so if people have strong feelings about this definitely reach out it's not in our baseline but it's something that we you know want some feedback from the Community.
Emilio Nanni: Okay, and with that i'd be happy to answer any questions.
Ivana Hristova - STFC UKRI: Yes indeed, thank, thank you very much for this very informative and detailed an interesting talk.
Ivana Hristova - STFC UKRI: I stop the recording.