 energy per charge, this acceleration potential we know it here because we command the instrument and the speed inside here, the time of light chamber, we just replace it by the length of the time of light chamber over the time of light. The time of light also we measure. So that's how we get an estimation of the mass per charge. Now for this kind of, so this is a particular for this what we call straight through. For this straight through you see it directly here that the mass per charge it depends on the energy per charge and so it depends if the ions have the higher energies then the time of light will be lower and so the mass per charge really depends here on the energy per charge and also on the direction of the entrance of the ions because they can be diffused and they can be detected at the edges of this microchannel plate and this can affect the mass per charge. Now the very particularity and actually the strength of this instrument is this other part the effect of the linear electric field here and not all actually the mass spectrometers have this linear electric field. Why this is very important because now if we talk about this positively charged ions how do we calculate the mass per charge here we can reduce the problem to a harmonic oscillator and if we write as well so from the equation we have the mass times so the acceleration it will be equal to well minus the charge constant k times z which is the distance of here reflection and if we divide by the mass by the mass then we obtain this relation and here you can note the angular frequency omega squared and from this omega squared equal to this kind of ratio we can obtain this formula here t prime is the half period of for the oscillation and which represent as well the time of light that is detected in the upward detector and so we have a direct relation relating the mass per charge to the time of light without any dependence on the energy so and this is very actually weird I mean maybe it's difficult to imagine that whatever is the energy let's say of the oxygen that enters the instrument it would always be if it leaves if it's positively charged it was always be detected at the same time of light independently of the energy of the ions that enters. Now let me show you some examples so this is actually observations made in the lab so we send the beam of ions toward the instrument to calibrate it and to see if the linear electric field part works very well and the straight through part works very well so we send the beam of helium plus ions and also potassium ions k plus at different energies at one kv and four kv in red and you see that for the linear electric fields the ones that are reflected upward whatever is the energy the helium plus ions they are always observed at the same time of light the x-axis is the time of light of the ion and it's the same for the potassium so the mass per charge does not depend on the energy however if we look at the straight through data so the neutrons or the negatively charged ions we see a difference between the spectra the larger energy so the red lines will have lower time of light because we'll have well they have had energies and also well for the potassium ions as well another difference you can see is that the spectra for the linear electric field they are almost kind of Dirac actually they are very well resolved in mass however for the straight through ions because they depend on the energy and and the direction they will be diffused actually and the spectra presents some tails like this so this the first part the left the linear electric field gives a very high mass resolution much better than the straight through however if you look on the y-axis here it shows the counts the counts are much lower 10 order of well here we have maybe 100 counts and here we have yes 1000 counts so most of the ions that enter the time of light they actually leaves as neutrals or negatively charged and only some of them they will be reflected upwards okay i i don't have much time maybe i can continue later tomorrow if if it's okay yeah okay so this is why the mass resolution is very important i will just finish on the mass spectrometer why this is very important to have a very high mass resolution so here also i will show you comparison between so this is actually ion beam sense in the lab so this is the total ions measured by the instrument in comparison to simulated data using simulations and if we send different ion beams so the colors here are not very well shown but helium plus nitrogen the carbon or sodium ions actually the first panels are the straight through the second panel are the linear electric field and you can see at least a very well consistency between the simulated data and the observations in the lab it's very it's not very clear here but the time of light they coincide very well and also the main point here if we take for instance this is the oxygen carbon ions and if we take the carbon oxygen and nitrogen these three curves you see that the curves overlap and if i if in the data if we have a curve like this then we would have an overlap between the carbon ions and the oxygen and the nitrogen and it will be very difficult sometimes to distinguish between these three ions however if we have Dirac kind of spectra we can very well and validate or confirm if we actually because there is no overlap between the carbon ions is just one spectra and the nitrogen as well there's no overlap between the spectrum now if i have maybe two minutes or i will just show you actually it's the first time that i show this in public i will show you the latest observations that we measured from the mass spectrometer msa during the second mercury flyby of pepi colombo so pepi colombo flew by mercury in june 23rd of june so a couple of months ago and during this flyby so here maybe there was a movie just to show you actually for the first time like even messenger so if you may know messenger was another orbiter that it's a NASA mission that flew by the planet and for the first time we we were at an altitude very close to the planet at about 198 kilometers so very close to the surface of the planet and we could well these are some actually video made from different pictures taken from the camera on board the spacecraft that when we saw the surface of the planet and the different craters here but well other than the images we could perform there's well some in situ measurement and this is just here when the trajectory of the spacecraft and here i'm just showing you well despite the lots of data gaps the y axis is the energy per charge as a function because we are in a cruise space the short answer is that we are in a cruise space we are operating in low mode and so we have lots of telemetry loss loss of data because of telemetry reasons this is the short answer and and we could measure the iron actually along this trajectory not from these data but from the electron data we could also identify different boundary crossings the magnetopause crossing in and out and the bow shock crossings once and then we got in the solar wind and this structure here is actually foreshock structure structure that we observed in the solar wind so i want to just to show you the time of light spectra so this is actually around this line is the closest approach around the planet and i will show you now two time of light spectra one close to the closest approach and another one in the solar wind and this is what really the data look like of the time of light spectra y axis is the energy per charge as a function of the time of light and the color bar here represents the counts the red curves represent the theoretical actually uh well actually not the dotted curves represents uh blackers the theoretical time of lights for different mass per charge values so we know that the first red curve uh black red dotted curve is time of light for mass per charge equal to one the second one is mass per charge equal to two how do we plot this curve is using the formula that i showed you before and so on we increase the different mass per charges that would represent actually different ions in the environment and when we look at the observations we see at least from these two plots that around the closest approach we have lots of counts actually that overlap very well with the theoretical worker for the mass per charge equal to one so now we know that this is this would represent proton ions the second represents the helium plus ions and and so on and this one lines would represent uh well sorry this one represents the alpha particles and this line would represent the helium plus ions and if we compare between the closest approach and the force operation well this this would be another talk but we could also identify some so helium plus ions and alpha particles around the closest uh well at least plenty of helium plus ions around the closest approach now in addition and you see these are curved lines with big which it's curved it means that they depends on the energy now in addition to this we also observe these signatures which kind of vertical they are not really curved and these are actually we interpret this as uh uh uh uh related to left protons what happens is that during the crossing of the carbon foil the protons will enter as a neutral or positively charged now the neutral will be detected downwards and the positively charged will be reflected upwards now during this cruise phase we are not measuring the left protons because it's in we are operating in low mode and uh but still I mean the instrument is detecting these left protons but then what happened is that secondary electrons are emitted simultaneously and accelerated downwards and so they will be detected in the straight through bottom yes so we have an overlap uh an overlap of indirect left signature of the protons and the straight through signatures of the protons and well we cannot do anything about this I mean these are the data uh we need to deal with and try to clean them well uh actually not really no because but yeah so we need to find a way to clean to filter this data and to actually uh uh yeah to to know the real contribution of the protons at least from this case but uh to be continued tomorrow thank you thank you Elena for a nice talk uh have you one question before honestly you know that uh tomorrow afternoon we will have the disinformation with lina and say that we have more questions that might be a good one a couple of announcements uh please pass uh what what's your announcement for tomorrow for wednesday stop just a reminder yeah okay and uh uh this afternoon we have a false definition and and then uh one reflection I want to make uh it's very coffee or refreshing to see I mean from the summit I've been and I promoted the participation of more women in our college and it's very refreshing to see the both now that we are you and we have a larger percentage of women participating and we have a also not just from the participant side but also from the lecture side we have very great lecture from uh people like lina and a take home message is that when we go back home to your institution to your country to to take steps to promote the participation of more women because it's a fantastic deal yes yeah so thank you very much there is no subtitle so oh thank you I hope it was here I hope it wasn't here I hope it wasn't here yeah yes it's moving pictures it was so I that might work oh okay and it's just saying that this well I'm the agent for whatever you want. So yeah, let me do it. I'm going to do it. What are you going to do? What are you going to do? I'm going to follow you. If I do it, then I'm going to use it that way. But I'm just going to do it that way. I'm just going to follow you. Now you follow me. Ryan. Hi. What did you do on the weekend? I went to Venice. Venice? Yeah. Venice? It was yesterday. I came there on Tuesday. I came back this evening. What is the day you finished? I had a working week in the master's. Say again? I had a working week in the master's. I finished next week. Yeah. So I slept there for the night. You're in? In the center? What? Who's getting scared? RTA. In a mess. In a mess. In a mess. I thought it was going to be a huge hit in the mood for a federal. Yeah. It's normal to be in the middle of it. But then it's just, oh, they should also be just taking this long to make sense. I thought it was going to be a fun. I'm trying to make sense. In one thing, I'm working on experimenting with this club. That's why we're doing this. We're going to be doing the same thing every time. We're doing the same thing every time. So that's why I was in the middle of it. Okay. I was in the gym. You were about to do the next class. I was in the gym. I was in my new age. In the next. Actually I was in the gym. No, I'm in the gym. I'm not in the gym. In the gym. I don't know what's up. I just try to understand. I don't know how many things that they tell you but you don't understand it. Yes. That's why we're getting to them. Because we're the partners with them. Yeah. Yeah. Yeah. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No.