WEBVTT 00:00.000 --> 00:08.000 That's okay, fine. 00:08.000 --> 00:15.000 So this is a bit wide subject. 00:15.000 --> 00:18.000 So I will speak a bit about accelerators. 00:18.000 --> 00:21.000 And more or so, 00:21.000 --> 00:27.000 not slides about how RF is used in accelerators. 00:27.000 --> 00:32.000 And then the core of the presentation 00:32.000 --> 00:35.000 would be about how we use right how big 00:35.000 --> 00:39.000 to distribute audio frequency. 00:39.000 --> 00:42.000 So particular accelerators. 00:42.000 --> 00:47.000 Probably you all know about this formula. 00:47.000 --> 00:51.000 Where the main point is that this is a very large factor. 00:51.000 --> 00:54.000 So there is an equivalence between mass and energy. 00:55.000 --> 00:58.000 And very small mass can create a lot of energy. 00:58.000 --> 01:01.000 And this is what we use in atomic plants. 01:01.000 --> 01:08.000 So we create a lot of electricity from very small mass. 01:08.000 --> 01:11.000 What we do at a certain is exactly the opposite. 01:11.000 --> 01:16.000 So we take a lot of energy and we create 01:16.000 --> 01:20.000 in a very non-optimized way, 01:20.000 --> 01:23.000 a very small amount of matter. 01:23.000 --> 01:26.000 And this matter is, I would say, 01:26.000 --> 01:28.000 a little bit random, but we can, 01:28.000 --> 01:31.000 by observing this matter, 01:31.000 --> 01:34.000 we can try to undo physics. 01:34.000 --> 01:36.000 And we can try to understand it a bit more 01:36.000 --> 01:39.000 the lower of the physics. 01:39.000 --> 01:45.000 So how do we get, how do we get this energy? 01:45.000 --> 01:49.000 This energy to create matter. 01:49.000 --> 01:52.000 So you need energy. 01:52.000 --> 01:55.000 It should be very concentrated. 01:55.000 --> 01:58.000 So it will create any mass. 01:58.000 --> 02:03.000 And the easiest way to concentrate a lot of energy 02:03.000 --> 02:08.000 is using kinetic energy and to transfer 02:08.000 --> 02:13.000 where to concentrate using small particles. 02:13.000 --> 02:15.000 This energy. 02:15.000 --> 02:18.000 So you need to accelerate particles. 02:18.000 --> 02:23.000 And Einstein also had because this factor can go, 02:23.000 --> 02:27.000 can be very, very high. 02:27.000 --> 02:31.000 So we need to accelerate particles. 02:31.000 --> 02:34.000 And how do we do that? 02:34.000 --> 02:39.000 You think it's different, low and slow, 02:39.000 --> 02:44.000 which gives you the, 02:44.000 --> 02:49.000 which said that you can have a strength using 02:49.000 --> 02:54.000 his electric field or a magnetic field. 02:54.000 --> 02:57.000 There is something interesting here, 02:57.000 --> 03:00.000 is the speed of the, 03:00.000 --> 03:02.000 in our case of the particle. 03:02.000 --> 03:04.000 And if the speed is very high, 03:04.000 --> 03:08.000 you can have also a nice factor. 03:08.000 --> 03:12.000 Unfortunately, because it's a vectorial product, 03:12.000 --> 03:17.000 you cannot accelerate any object using a magnetic field. 03:17.000 --> 03:22.000 However, you can still use it to steer or to change 03:22.000 --> 03:24.000 the direction of an object. 03:24.000 --> 03:27.000 So we need, in any case, an electric field 03:27.000 --> 03:31.000 to accelerate a particle. 03:31.000 --> 03:40.000 And we use a magnetic field to steer the particle. 03:40.000 --> 03:45.000 You have some, I would say, particle limits. 03:45.000 --> 03:48.000 For example, the magnetic field is an electric field. 03:48.000 --> 03:49.000 It's an electric field. 03:49.000 --> 03:52.000 It's an electric field. 03:52.000 --> 03:54.000 It's an electric field. 03:54.000 --> 03:56.000 It's an electric field. 03:56.000 --> 03:59.000 It's an electric field. 03:59.000 --> 04:03.000 It's something which is a particle limit of our, 04:03.000 --> 04:07.000 our contact energy. 04:07.000 --> 04:11.000 So in accelerators, you can find RF cavities, 04:11.000 --> 04:15.000 which are the way that electric field is applied 04:15.000 --> 04:17.000 on the beam. 04:17.000 --> 04:20.000 So the beam goes through the cavity 04:20.000 --> 04:23.000 and is being accelerated. 04:23.000 --> 04:27.000 And you have a lot of magnet 04:27.000 --> 04:29.000 around the accelerators. 04:29.000 --> 04:33.000 So here you have the inside this pipe, 04:33.000 --> 04:35.000 which is what you call the chamber. 04:35.000 --> 04:37.000 Like you can chamber. 04:37.000 --> 04:40.000 So the particle goes through the pipe. 04:40.000 --> 04:46.000 And you have many, many magnets around the pipes 04:46.000 --> 04:50.000 to curve the beam. 04:50.000 --> 04:55.000 Also for focusing and focusing. 04:55.000 --> 05:00.000 You have many two main topologies of accelerators. 05:00.000 --> 05:05.000 So the most classical one is linear accelerators, 05:05.000 --> 05:07.000 which is, I would say, 05:07.000 --> 05:12.000 it's a bit simpler and is still used. 05:12.000 --> 05:16.000 The main problem is that you need to accelerate 05:16.000 --> 05:18.000 for a long time. 05:18.000 --> 05:20.000 Well, for a long time, 05:21.000 --> 05:25.000 the gradient of the x-axis feed is limited. 05:25.000 --> 05:29.000 Also it's not a very efficient topology, 05:29.000 --> 05:35.000 because the particle goes only once through every element. 05:35.000 --> 05:42.000 So you need to develop structure only 05:42.000 --> 05:46.000 for a very few small amount of time. 05:46.000 --> 05:48.000 Every structure will be used only 05:48.000 --> 05:53.000 at a very small amount of time by every particle. 05:53.000 --> 05:56.000 That's the main, well, the first topology. 05:56.000 --> 05:59.000 So in order to be able to away use every element, 05:59.000 --> 06:03.000 there is a simple idea of doing a circular accelerator. 06:03.000 --> 06:07.000 So like this, we can see it goes all around. 06:07.000 --> 06:09.000 It's not exactly a circuit, 06:09.000 --> 06:15.000 but you see how it is being made at least closed. 06:16.000 --> 06:21.000 So the main advantage is that you will use every element of the accelerator. 06:21.000 --> 06:24.000 So the beam can stay for a very long time 06:24.000 --> 06:28.000 inside this kind of accelerator. 06:28.000 --> 06:31.000 The main issue is that it's a bit, 06:31.000 --> 06:35.000 it's a more complex topology. 06:35.000 --> 06:37.000 So you have to steer correctly the beam, 06:37.000 --> 06:40.000 so that it comes back at the same point. 06:40.000 --> 06:43.000 And you suffer also from synchronous effect, 06:43.000 --> 06:46.000 which is a low of physics. 06:46.000 --> 06:48.000 So each time you accelerate a particle, 06:48.000 --> 06:51.000 it emits some photon. 06:51.000 --> 06:54.000 So it lose some energy. 06:54.000 --> 06:58.000 And this is a particular tool for electron, 06:58.000 --> 07:01.000 and much less for a photon. 07:01.000 --> 07:05.000 Because it's a low dependent on the weight of the particle, 07:05.000 --> 07:10.000 power, power, power, power. 07:10.000 --> 07:13.000 So for circular accelerators, 07:13.000 --> 07:17.000 one of the main problems is to keep the beam inside this, 07:17.000 --> 07:19.000 here for L.S.E.S.R.T, 07:19.000 --> 07:24.000 which is about 5 cm, 07:24.000 --> 07:26.000 so it's quite small. 07:26.000 --> 07:30.000 And for L.S.R.T, for example, the circumference of the accelerator 07:30.000 --> 07:34.000 is about 27 cm, so you need to be quite precise. 07:34.000 --> 07:39.000 If you don't, it's very simple. 07:39.000 --> 07:41.000 Due to the energy of the beam, 07:41.000 --> 07:48.000 it will do it all in the accelerator, 07:48.000 --> 07:52.000 so it's a valid factor. 07:52.000 --> 08:02.000 So to steer the beam, we use magnetic fields, 08:03.000 --> 08:06.000 and the magnetic field, due to the low physics, 08:06.000 --> 08:08.000 the faster the particle is, 08:08.000 --> 08:12.000 the stronger the magnetic field should be. 08:12.000 --> 08:17.000 So you need to synchronize very precisely the magnetic field, 08:17.000 --> 08:21.000 with the speed of the particle. 08:21.000 --> 08:24.000 And hence, this is the name of the electron, 08:24.000 --> 08:31.000 because you synchronize the magnetic field 08:31.000 --> 08:35.000 and the energy of the beam. 08:35.000 --> 08:42.000 So this is that says the main channel of accelerators. 08:42.000 --> 08:45.000 What do we, what can we accelerate? 08:45.000 --> 08:50.000 So particles and the easiest one will be electron, 08:50.000 --> 08:55.000 because it's very easy to produce, 08:55.000 --> 08:58.000 but the advantage is it's very light, 08:58.000 --> 09:02.000 so it's very subject to synchronization. 09:02.000 --> 09:07.000 If you curve an electron, 09:07.000 --> 09:10.000 if you accelerate it, 09:10.000 --> 09:12.000 it will generate a lot of photon, 09:12.000 --> 09:16.000 it will lose a bit of energy, which is problematic. 09:16.000 --> 09:18.000 We can also accelerate protons, 09:18.000 --> 09:23.000 so that we actually do mainly at some for LHC. 09:23.000 --> 09:27.000 It's much heavier, so let's back to synchronization. 09:28.000 --> 09:31.000 I thought it's not an elementary particle, 09:31.000 --> 09:39.000 so it's, you get less precise result from one portal 09:39.000 --> 09:43.000 to a competitor electron. 09:43.000 --> 09:46.000 We can also, and we also accelerate ions, 09:46.000 --> 09:50.000 which are, I would say, heavier, 09:50.000 --> 09:55.000 and it's a bit different kind of application of physics. 09:56.000 --> 09:59.000 We can also accelerate antiparticles, 09:59.000 --> 10:02.000 which is interesting for collision, 10:02.000 --> 10:06.000 because it will create a lot of collision energy, 10:06.000 --> 10:13.000 and you can use, because the charge is opposite of the particle, 10:13.000 --> 10:21.000 you can use the same pipe to make the particle an antiparticle travel. 10:22.000 --> 10:27.000 For LHC, if you remember the pictures, 10:27.000 --> 10:31.000 you have two, we only accelerate proton, 10:31.000 --> 10:34.000 and there are two pipes, 10:34.000 --> 10:37.000 so it's a beam, there are two beams, 10:37.000 --> 10:39.000 which have a little bit of direction. 10:43.000 --> 10:49.000 It's a very quick overview about accelerators, 10:49.000 --> 10:52.000 a lot of subjects you can, 10:52.000 --> 10:54.000 well, collected to accelerators, 10:54.000 --> 10:56.000 like about how we do collision, 10:56.000 --> 10:58.000 how we do the detectors, 10:58.000 --> 11:00.000 all the instruments we have, 11:00.000 --> 11:03.000 along the accelerator to know about 11:03.000 --> 11:06.000 to characterize better the beam. 11:06.000 --> 11:12.000 There is how we inject or inject a beam 11:12.000 --> 11:15.000 from or out of an accelerator. 11:16.000 --> 11:20.000 There are a lot of problems around magnet, 11:20.000 --> 11:22.000 any particular positive magnet, 11:22.000 --> 11:25.000 which are used for LHC. 11:28.000 --> 11:31.000 Vacuum, because all the particles 11:31.000 --> 11:34.000 have in the vacuum chamber, 11:34.000 --> 11:37.000 and there are also a lot of conservation 11:37.000 --> 11:40.000 about safety and security. 11:40.000 --> 11:41.000 So if you are more, if you are 11:42.000 --> 11:44.000 interesting in some of these subjects, 11:44.000 --> 11:49.000 I have a reference at the end of the presentation. 11:49.000 --> 11:53.000 So CERN is not exactly about only LHC, 11:53.000 --> 11:55.000 anyone who has probably heard about LHC, 11:55.000 --> 12:01.000 but in fact we have a lot of different installations, 12:01.000 --> 12:03.000 and for proton everything 12:03.000 --> 12:06.000 start from this smaller, 12:06.000 --> 12:09.000 linear accelerator, which is named 12:09.000 --> 12:14.000 LHC4, and the source at the origin of the proton beam 12:14.000 --> 12:18.000 is a very small bottle of hydrogen, 12:18.000 --> 12:21.000 and I think you can use one bottle, 12:21.000 --> 12:24.000 we need one bottle every year. 12:24.000 --> 12:29.000 In LHC4, LHC4 accelerates up to about 12:29.000 --> 12:34.000 half of the speed of the light. 12:34.000 --> 12:39.000 Then we go to booster, which accelerates a bit more 12:39.000 --> 12:42.000 up to 95%. 12:42.000 --> 12:45.000 Then we go to the proton cyclone, 12:45.000 --> 12:53.000 which accelerates to 99.9% of the speed light. 12:53.000 --> 12:59.000 Then we go to SPS, super proton cyclone, 12:59.000 --> 13:03.000 which I will talk much more about it, 13:03.000 --> 13:09.000 and then goes almost to the speed of the light. 13:09.000 --> 13:12.000 And then there is LHC, 13:12.000 --> 13:16.000 and it's even more almost the speed of the light. 13:16.000 --> 13:19.000 So it's going to be about to speed of the light 13:19.000 --> 13:23.000 minus maybe 10 kilometers per hour. 13:23.000 --> 13:26.000 It's not. 13:26.000 --> 13:32.000 It's a bit more, so it needs about five minutes to fill 13:32.000 --> 13:37.000 LHC, so it's filled by part using the beam 13:37.000 --> 13:40.000 as criteria as before. 13:40.000 --> 13:43.000 Then it's what we call one pup, 13:43.000 --> 13:47.000 so to reach the maximum speed of the amount of energy 13:47.000 --> 13:50.000 we need about 30 minutes. 13:50.000 --> 13:57.000 And then we can do physics or collision during the boat. 13:58.000 --> 14:01.000 And with the maximum 20 hours, when everything goes well, 14:01.000 --> 14:05.000 it's about 20 hours. 14:05.000 --> 14:08.000 So what we're using, what we're operating the LHC, 14:08.000 --> 14:12.000 the user, I said that there are still used for other experiments. 14:12.000 --> 14:15.000 It's mainly fixed target experiments, 14:15.000 --> 14:19.000 so we send the beam against a target. 14:19.000 --> 14:25.000 And it also means that very, very small part of the beam 14:25.000 --> 14:30.000 produced by the extractile, let's say, from the hydrogen bottle 14:30.000 --> 14:33.000 goes to the LHC. 14:33.000 --> 14:36.000 So we're also talking about LHC. 14:36.000 --> 14:39.000 It's for sure our main instrument, 14:39.000 --> 14:43.000 but there are also many, it's used a very small amount of the beam, 14:43.000 --> 14:50.000 and there are also a lot of signal which happens around. 14:51.000 --> 15:00.000 Okay, that's about, let's say, a few words about accelerators. 15:00.000 --> 15:04.000 I didn't explain a lot about, well, 15:04.000 --> 15:09.000 it didn't speak a lot about LHC, right now, 15:09.000 --> 15:16.000 because it's what I'm talking, what I will talk just now. 15:16.000 --> 15:21.000 In order to accelerate particles, 15:21.000 --> 15:25.000 we use what we call RF cavities, so basically the arcade. 15:25.000 --> 15:28.000 It's also a big topic. 15:28.000 --> 15:33.000 There are, there is, so, right off, I can see, 15:33.000 --> 15:37.000 electric fields which are inside these cavities. 15:37.000 --> 15:41.000 And there's a beam, also inside the cavity. 15:41.000 --> 15:46.000 And when everything goes well, the electric fields 15:46.000 --> 15:57.000 gives energy to the beam, so it accelerates the beam. 15:57.000 --> 16:05.000 So as I said, cavities are very complex topic. 16:05.000 --> 16:10.000 The frequency goes from negative to negative. 16:10.000 --> 16:15.000 If you have low frequency, it means you need to have 16:15.000 --> 16:22.000 larger cavities because it depends on the wavelength of the electric field. 16:22.000 --> 16:25.000 And there's a hand if you have high frequency, 16:25.000 --> 16:30.000 it means you have a lot of tolerance constraint on the cavity. 16:31.000 --> 16:37.000 Also, there is a problem of bandwidth. 16:37.000 --> 16:44.000 So the frequency increase with the speed of the beam, 16:44.000 --> 16:47.000 which means you need a certain bandwidth. 16:47.000 --> 16:55.000 And you cannot have, well, it's very difficult to have a cavity 16:55.000 --> 17:02.000 which can tune to a very large, effective bandwidth. 17:02.000 --> 17:07.000 At certain, we use cavities at 400 megawatts for LHC. 17:07.000 --> 17:11.000 200 megawatts for SPS, so which is, et cetera, just before LHC. 17:11.000 --> 17:17.000 And for PS, we have a lot of different cavities. 17:17.000 --> 17:21.000 There are even cavities which you can tune for a wide bandwidth 17:21.000 --> 17:26.000 because they are mechanically adjusted. 17:26.000 --> 17:31.000 I don't know much about that. 17:31.000 --> 17:34.000 So that's a cavity. 17:34.000 --> 17:40.000 And the source of the cavities is generated by what we call 17:40.000 --> 17:42.000 the lower LHF system. 17:42.000 --> 17:50.000 So this is a system which is responsible of giving the frequency to the cavities. 17:50.000 --> 17:53.000 And it's organized around feedback loops. 17:53.000 --> 17:58.000 And to get the feedback, you have pick up inside the cavities. 17:58.000 --> 18:05.000 And close to the cavities to get the phase of the wave. 18:05.000 --> 18:10.000 And also to the phase of the beam. 18:10.000 --> 18:18.000 And in the middle of that, so between LHF control, LHF and cavities, 18:18.000 --> 18:20.000 you have some amplifiers. 18:20.000 --> 18:25.000 So here this is what we part of what is used for SPS. 18:25.000 --> 18:31.000 And this is where we can see that we are talking about high energy physics 18:31.000 --> 18:38.000 because you need a lot of energy to be given to the beam. 18:38.000 --> 18:43.000 And so you can see for example there are some coax cavities. 18:43.000 --> 18:48.000 But it's slightly different from your standard BNC cable. 18:48.000 --> 18:52.000 So this is triode. 18:52.000 --> 18:55.000 And also energy given by your triode are combined. 18:55.000 --> 19:01.000 And then sand into the wave. 19:01.000 --> 19:08.000 To the SPS, through the tunnel. 19:08.000 --> 19:12.000 And in addition, so this is using coax, in addition, we are also depending on the frequency. 19:12.000 --> 19:15.000 And also use a wave guide. 19:15.000 --> 19:18.000 If the frequency is higher. 19:18.000 --> 19:21.000 So for 200 minutes, we use coax. 19:21.000 --> 19:29.000 And for 800 minutes, for example, we can use wave guide. 19:29.000 --> 19:34.000 So this is very important. 19:34.000 --> 19:37.000 I think now I spoke about the beam. 19:37.000 --> 19:44.000 Which is how particle travel inside the vacuum chamber. 19:44.000 --> 19:47.000 But the beam is not exactly continuous. 19:47.000 --> 19:49.000 It's organized by bunches. 19:49.000 --> 19:53.000 So by group of particles. 19:53.000 --> 19:58.000 The main reason for that is because we are using wagio frequency. 19:58.000 --> 20:02.000 It's idealis, you know, is it all waves. 20:02.000 --> 20:10.000 And if you have a continuous presence of particle, at some point it will be, 20:10.000 --> 20:14.000 So for particle, let's say, being here, it will be. 20:14.000 --> 20:17.000 We have a negative field. 20:17.000 --> 20:21.000 So it will have a strength in one direction. 20:21.000 --> 20:28.000 And then there will be a few that are laterators. 20:28.000 --> 20:30.000 It will be positive. 20:30.000 --> 20:33.400 So it will, the strength will be the opposite direction. 20:33.400 --> 20:41.200 So if you try to send a continuous flow of particles, naturally, 20:41.200 --> 20:44.800 it will, it will be, it will be, it will be go by, 20:44.800 --> 20:49.800 goped by, by, by, by, by benches. 20:49.800 --> 20:54.200 And, um, air control. 20:54.200 --> 20:58.200 So we need to closely control the amplitude, you know, 20:58.200 --> 21:02.400 not to know exactly how much we give energy to the, to the beam. 21:02.400 --> 21:07.400 And we also need to very precisely control the phase, 21:07.400 --> 21:14.800 because, um, if, uh, at one point you actually like particle 21:14.800 --> 21:20.000 and then at the next turn, you are not exactly at the right phase, 21:20.000 --> 21:26.200 but maybe before you will change the, uh, you will give, 21:26.200 --> 21:31.000 you might, the, the, the beam, the, this group of particle, 21:31.000 --> 21:33.800 which is not exactly the, what we, what you want to do. 21:33.800 --> 21:37.600 So you need to have a very good whole, uh, phase. 21:37.600 --> 21:44.800 In a different way, you cannot have the group anywhere on the, on the wave, 21:44.800 --> 21:51.800 because you also want to keep the bunch as, as, as, as, as, as possible. 21:51.800 --> 21:56.600 So I think that you want to have a uniform speed, uh, of every particle, 21:56.600 --> 22:01.800 because the particle will see all, on the particle, which is the same, uh, 22:01.800 --> 22:03.400 magnetic field. 22:03.400 --> 22:10.400 And if the magnetic field is, uh, is related as to be synchronized with, uh, 22:10.400 --> 22:12.600 with, uh, energy of the beam. 22:12.600 --> 22:16.600 And if it's not, so even a particle which are, which have two more, uh, 22:17.400 --> 22:22.600 or not enough energy, there will be curved too much or not enough. 22:22.600 --> 22:30.600 And they will go, uh, outside of their orbit and, uh, uh, go to the, 22:30.600 --> 22:37.600 much to the world of the chamber, which is not exactly what we, what you want to, to do. 22:38.200 --> 22:48.400 So the RF is very, uh, a, uh, a, a, a technique or told in order to have a very well defined, uh, 22:48.400 --> 22:52.000 orbit and precisely the control. 22:52.000 --> 22:59.000 So it's a efficiency and safety, for the, at the same time. 22:59.000 --> 23:01.800 This is about RF. 23:01.800 --> 23:07.400 So now we're attaching the, that bit the curves of the, of the discussion, of the top. 23:07.400 --> 23:09.080 What type of it? 23:09.080 --> 23:11.200 So quick-plantation. 23:11.200 --> 23:13.840 Why type of it is a technology we have developed at 23:13.840 --> 23:19.760 certain in order to distribute time, 23:19.760 --> 23:25.520 if I can see, over it and it. 23:25.520 --> 23:33.680 It's open source and let's say it's try to use, 23:33.680 --> 23:34.800 which is a standard technology. 23:34.800 --> 23:45.200 So there is no new instrument or no new component design for that. 23:45.200 --> 23:48.360 What we do is, so you can think it. 23:48.360 --> 23:52.680 You can think about it like a standard network, 23:52.680 --> 23:58.520 but for each switch, we are able to recover the frequency 23:58.520 --> 24:03.640 from the network, so from another switch. 24:03.640 --> 24:09.160 And it's combinatorally, because ethernet is using 24:09.160 --> 24:14.800 cymbals every time, and you can all the transceiver, 24:14.800 --> 24:23.040 all the transceiver, can give you the frequency of the modulation. 24:23.040 --> 24:30.400 And we use this frequency to discipline a local oscillator. 24:30.400 --> 24:33.960 So every switch and every node, as a local oscillator, 24:33.960 --> 24:37.800 was frequency is the same as the master oscillator, 24:37.800 --> 24:44.240 which is how can it be that? 24:44.240 --> 24:51.280 Which source at the end is atomic clock and GPS source. 24:51.280 --> 24:54.160 So that's for frequency. 24:54.160 --> 24:56.080 Of course, when you recover the frequency, 24:56.160 --> 25:02.960 it's a lot of noise of phase noise or jitter. 25:02.960 --> 25:08.200 So we need to clean as much as possible this frequency. 25:08.200 --> 25:13.600 And this is done by a standard techniques about what 25:13.600 --> 25:16.080 we discipline a local oscillator, we use PLL in other 25:16.080 --> 25:22.760 to clean as much as possible as a phase noise. 25:22.840 --> 25:28.160 We also need to keep the phase. 25:28.160 --> 25:33.000 And for that, we have, I would say, 25:33.000 --> 25:36.840 hands the PTP protocol, which is something 25:36.840 --> 25:38.360 also standard. 25:38.360 --> 25:42.000 And we are able to measure the transmission time 25:42.000 --> 25:44.080 between two switches. 25:44.080 --> 25:49.080 So once it has been measured, we know how to, 25:53.760 --> 25:56.680 we know, to compensate the phase of the oscillator, 25:56.680 --> 25:59.440 of the next oscillator, to be exactly a line, 25:59.440 --> 26:05.440 almost exactly a line to its master. 26:05.440 --> 26:10.920 Right now, we are using one gigabit Ethernet, 26:10.920 --> 26:13.520 and we are using optical fiber. 26:13.520 --> 26:19.240 And we can reach a metric claim, and what we achieve, 26:19.320 --> 26:23.000 is a son and a second accuracy, with about 26:23.000 --> 26:26.200 the PMS implementation, a 50-pcon precision. 26:30.040 --> 26:35.360 I would say the nice thing about what type it is, 26:35.360 --> 26:40.120 you can have quite a good accuracy and precision 26:40.120 --> 26:45.120 using a very cost effective material of hardware. 26:50.160 --> 26:53.560 You can do a synchronization using, 26:53.560 --> 26:55.600 you can do, I would say, what's the synchronization 26:55.600 --> 26:56.960 using even cheaper component? 26:56.960 --> 27:02.800 Like standard Raspberry Pi can do something 27:02.800 --> 27:05.920 in the order of Microsoft's gond. 27:05.920 --> 27:08.720 You can do some much better precision, 27:08.720 --> 27:10.920 but it requires a methodology instrument, 27:10.920 --> 27:12.920 which are way more expensive. 27:14.120 --> 27:17.960 So I would say it's quite a nice, sweet point. 27:19.320 --> 27:20.480 Using for electronics. 27:24.760 --> 27:27.760 If you want to know more about what type it, 27:27.760 --> 27:32.760 yeah, yeah, it is a official website. 27:34.760 --> 27:37.720 It's also interesting of how we, 27:38.840 --> 27:42.760 I would say, which type it would stop the ecosystem. 27:44.120 --> 27:45.440 So it's mainly what type it is, 27:45.440 --> 27:48.200 mainly composed of switches like this, 27:48.200 --> 27:50.920 and Android, which are very values, 27:50.920 --> 27:52.280 depending on the objectification. 27:52.280 --> 27:56.920 We used on the fiber, on the other transceivers. 27:58.720 --> 28:02.560 And you can buy switches like this, 28:02.560 --> 28:04.400 they're actually from Pi weight company. 28:05.320 --> 28:09.600 So I would say, everyone, not only we have developed 28:09.600 --> 28:12.440 the technology, but we have also made it easily, 28:12.440 --> 28:15.680 very diverse for anyone. 28:18.840 --> 28:23.840 So, finally, how we use RF for, 28:23.840 --> 28:26.320 how we use the type it's already for RF. 28:32.040 --> 28:35.040 So just before around COVID, 28:35.040 --> 28:40.040 we managed to win over the SPS RF system, 28:41.320 --> 28:43.920 so mostly low-level RF system. 28:44.880 --> 28:46.440 Okay, to decide it before, 28:48.320 --> 28:51.160 obviously, it was planned before COVID. 28:52.320 --> 28:55.920 The previous system was fully analog, 28:55.920 --> 28:57.480 which has some, 28:58.680 --> 29:03.160 by which we carry a very good knowledge of this system 29:03.160 --> 29:04.680 in order to tune it. 29:04.680 --> 29:09.680 And it was also quite, it has a lot of limitation. 29:11.320 --> 29:12.360 What type it was used, 29:12.360 --> 29:14.960 but it was chosen for the, for the new system, 29:14.960 --> 29:19.960 and we had the typed algorithmant. 29:20.160 --> 29:23.480 So good phase with possibility, 29:26.080 --> 29:27.360 less than 13, because second, 29:27.360 --> 29:29.480 which corresponds to one degree of precision 29:29.480 --> 29:33.280 for the efficacy of, of SPS, 29:33.280 --> 29:37.560 and I would say, quite low phase noise. 29:38.200 --> 29:43.200 So this is a new SPS level RF using my type it. 29:48.600 --> 29:50.360 Okay, I want them down to the detail, 29:50.360 --> 29:53.240 so here you have the, what you call the beam, 29:53.240 --> 29:56.080 cavities, and we measure, 29:59.120 --> 30:02.440 we speak up some characteristic of the beam, 30:02.440 --> 30:06.960 also some characteristic of cavities, 30:06.960 --> 30:11.520 and we do some single processing 30:12.600 --> 30:17.600 in order to, to drive, to drive the cavities. 30:18.720 --> 30:21.600 In addition to that, we also, 30:21.600 --> 30:26.400 we also enabled to distribute this RF signal, 30:26.400 --> 30:30.720 but fully digitally, to the board, 30:30.720 --> 30:33.400 and this is something which is quite interesting 30:33.400 --> 30:36.280 because at some, so at any point, 30:36.280 --> 30:39.160 of around the accelerator, 30:39.160 --> 30:42.080 you can know what is the current RF, 30:42.080 --> 30:47.080 which is interesting if you want to observe 30:47.880 --> 30:49.440 a particular bunch. 30:49.440 --> 30:54.440 So you need to have a tick, which is a clock edge. 30:55.960 --> 30:59.840 You would like to have a clock edge at any point around, 31:00.400 --> 31:03.240 so I thought to know when one particular bunch 31:03.240 --> 31:09.240 is passing around, and this is what is possible 31:09.600 --> 31:10.960 with the, with white rabbit. 31:10.960 --> 31:15.960 Before, it's was not possible with high precision, 31:16.320 --> 31:18.760 because we were using just cable, 31:18.760 --> 31:22.360 and cable has a subject to provide your variation, 31:22.360 --> 31:27.360 or whatever you want, and it's not that easy. 31:27.360 --> 31:32.360 So, it's white rabbit, you are also a new possible application. 31:38.160 --> 31:39.680 So, why are you a rabbit? 31:39.680 --> 31:41.840 First, it's a distributed system. 31:43.840 --> 31:46.440 So, we have different components, which are, okay, 31:46.440 --> 31:49.000 close together, but we need all of them to be 31:49.000 --> 31:52.760 precise, disacronized, and this is a purpose of a white rabbit. 31:54.440 --> 31:56.760 And this system is composed of, okay, 31:56.760 --> 31:58.640 it's almost free digital. 31:58.640 --> 32:03.640 So, you still have ADC and DAC for communication. 32:06.640 --> 32:08.520 We also have some other inputs, in particular, 32:08.520 --> 32:10.880 we are interesting in the beef field, 32:10.880 --> 32:15.880 which is measured inside the magnet, 32:18.840 --> 32:20.760 because, as I said before, 32:20.760 --> 32:25.480 we need to precise disacronize energy given to the beam 32:25.480 --> 32:27.080 with a magnetic field. 32:28.240 --> 32:33.240 And the result of this system is mainly the, 32:33.640 --> 32:35.440 what we call the frequency tuning word, 32:35.440 --> 32:40.440 which is a value, which correspond to a frequency. 32:44.560 --> 32:49.320 And this frequency tuning word is timestamp using white rabbit time. 32:49.320 --> 32:54.320 So, we know exactly at any point, 32:55.560 --> 32:58.480 what is, how to reproduce the frequency. 32:59.760 --> 33:02.440 And in this system, white rabbit is used for communication. 33:02.440 --> 33:06.720 So, for example, we transmit the frequency tuning word 33:07.720 --> 33:11.240 on white rabbit, and for synchronization, 33:11.240 --> 33:14.440 because this is a, all this system need to be synchronized, 33:14.440 --> 33:17.080 because we are using timestamp, 33:17.080 --> 33:19.480 and this is the purpose of, of we type it. 33:19.480 --> 33:24.480 So, how we generate, so, finally, we enter into the SDA, SDR word. 33:33.240 --> 33:36.480 How we generate good clock. 33:42.040 --> 33:44.360 So, for white rabbit, it's you for that, 33:44.360 --> 33:46.160 white rabbit doesn't, I would say, 33:46.160 --> 33:51.160 doesn't really help, you need good oscillators. 33:51.560 --> 33:56.560 So, what we use, I think so, so, it's an oscillator, 33:56.560 --> 34:01.560 which is inside oven, so it's something like a small box, 34:03.760 --> 34:07.360 which is heated at constant operator, 34:07.360 --> 34:09.440 to add a very stable oscillator, 34:09.440 --> 34:14.280 and it is disciplined with white rabbits. 34:14.440 --> 34:17.440 By disciplining, well, by tuning it, 34:17.440 --> 34:20.400 it means that you can slightly vary the frequency 34:20.400 --> 34:25.400 of the oscillator using a voltage source. 34:28.640 --> 34:33.640 Then we are using PLL, and we generate the fixed frequency 34:35.360 --> 34:36.840 using a radius. 34:39.480 --> 34:44.080 And this fixed frequency, which is here, 34:44.080 --> 34:49.080 is then modulated by a sine wave generated by the, 34:52.200 --> 34:55.840 by the FPGA from the frequency tuning word. 34:55.840 --> 34:58.120 And then filter, and then we have, 34:59.880 --> 35:03.440 asking as possible, sine wave. 35:04.760 --> 35:08.720 And using white rabbit, we have commands. 35:08.720 --> 35:11.000 So, for this kind of word, we have, we can, 35:11.000 --> 35:13.040 so we see the frequency tuning word 35:13.040 --> 35:16.360 to set this frequency, and we also receive 35:16.360 --> 35:21.360 possible reset to we align the clock. 35:23.000 --> 35:27.000 That's how we do for SPS. 35:32.560 --> 35:37.560 LHE, one slide, one slide. 35:37.560 --> 35:42.560 That's how we are slowly developing the, 35:45.080 --> 35:49.000 I would say, a roughly equivalent system for LHE. 35:49.000 --> 35:50.800 It's a different frequency, 35:50.800 --> 35:55.640 so it will be a slightly different electronics. 35:55.640 --> 36:00.640 Also, we have developed the electronics five, seven years ago, 36:02.200 --> 36:04.960 and many components are not available anymore. 36:05.960 --> 36:09.960 Thank you to some, thanks to some electronics chip provider. 36:13.880 --> 36:18.880 And we have a lower phase noise, 36:19.920 --> 36:24.920 because it's much more LHE's, 36:24.920 --> 36:28.760 we need much more accurate frequency. 36:28.760 --> 36:29.840 We want to send it more PLL, 36:29.840 --> 36:32.160 but we will use the frequency multiplier. 36:33.120 --> 36:38.120 In SPS, every single one, we synchronize every cycle, 36:38.120 --> 36:43.120 so about every, 30 seconds. 36:43.120 --> 36:45.880 We can do that anymore for LHE, 36:45.880 --> 36:50.880 because it will cycle our more than 20 hours. 36:52.600 --> 36:55.120 And we want to still be able to plug, 36:55.120 --> 36:58.600 or to plug a gap in the middle of a cycle, 36:58.600 --> 37:01.680 and to have automatic resetization. 37:02.680 --> 37:07.680 And also, RF, so we need to originate the RF frequency 37:10.960 --> 37:15.960 for experiment, because they tune the detector with the RF, 37:16.280 --> 37:21.280 because they need to precisely trigger detection 37:21.280 --> 37:24.920 when the bunch crosses inside the detector. 37:26.040 --> 37:27.360 So it's working progress. 37:28.080 --> 37:33.080 Not had finished, we are confident, but we will see. 37:37.280 --> 37:40.280 Finally, I'll give you a, okay, if you need to, 37:40.280 --> 37:42.160 if you want to know more about, 37:42.160 --> 37:46.360 I would say any subject that I talk about, 37:46.360 --> 37:48.760 I give you some references. 37:48.760 --> 37:52.760 In particular, if you're interested in about all the technology 37:52.760 --> 37:56.720 of how it works, how it works, 37:57.920 --> 38:02.600 so there is a certain organized accelerator school, 38:02.600 --> 38:05.960 which are one or two weeks long, 38:05.960 --> 38:07.960 so probably not, probably too long, 38:07.960 --> 38:12.960 but the interesting part of all the slides are available. 38:13.640 --> 38:18.640 So there are a lot of voice sources at available, 38:18.640 --> 38:22.320 sort of web about all the topics of accelerators. 38:22.760 --> 38:24.720 And that's all.