 Hello everyone and welcome to our seventh webinar of the series of Latin American webinars on physics My name is Federico von der Palen from the high-energy thermology group of the University of Antioquia in Meji in Colombia And I will be your host today. Our speaker Sergio Lopez Gela from the Technician University mentioned in Germany He's At the moment finishing his undergraduate his graduate studies his PhD In the theory group of Alejandro Ibarra Sergio's talk today is titled probing dark matter models with novel gamma ray features from cascade processes We are glad to have him as a speaker today We remind you that you can be part of the discussions writing questions and Comments using our Q&A system and on Twitter with the hashtag W a OP and I will now hang you over to Sergio. Hello everybody. Thank you very much for an introduction Federico and Now I'm going to going to share my screen so you can see my slides and Going on full screen mode and That's it. So I hope everybody can see everything. Okay So as Federico said I'm going to talk about some novel gamma ray features coming from cascade processes, which is mainly my work doing my My PhD so briefly the Outline of my talk is going to be this one First I'm going to do a very brief introduction on dark matter a motivation on why spectral features in the Gamma ray spectrum are important and then I'm going to go into my topic a Presenting you this box shaped spectra and then comparing with experimental data and showing some physical realizations and models So I'm going to try to vary to be very brief in this section of dark matter because Last webinar and Miguel Sanchez con the made a very good introduction. So I think I'm going to just repeat the most important facts So this is a very brief historical view of how the status of dark matter has been since the first Works done by this guy sticky and we've come a long way or almost 100 years and 15 years and It's kind of it's been already a lot of Observations that had been hints for dark matter We have the rotation curves and then also the structure formation and also the bullet craster and there are several others other Observations that's hint for dark matter Now I have here another way of presenting the sins which I like Very nicely and is a way of convincing also everybody about dark matter And in here instead of putting the time in this line. I put the size of Astronomical objects in which this missing mass Observations have been made and as you see we have from a galaxy scales from about 10 20 kilo par 6 in There a which have been seen in the rotation curves to some velocity distributions in clusters done by Friedrich Zwicky The bullet cluster which is one of the most clear hints for dark matter and then we have some Observations at cosmological level such as a large scale structures formation and the CMB any anisotropies and Here I'm trying to summarize How we how we summarize this knowledge that we have here? I'm presenting you this current knowledge about the energy content of the universe and As you see most of this observation supernova CMB and clusters point to a Larger amount of matter matter in the in the universe and we have only from what we have observed only a 5% of Barreons, and we have an overwhelming amount of Matter which we called dark matter Which is 26% of the energy content in the universe and then we have the dark energy part which makes a lot of of energy content most of it and is related to the Cosmological constant lambda and this is all very well summarized in the current cosmological framework that we've been calling Since a long time ago the lambda CDM model now in this model Dark matter has all Even more clear properties In the model is lambda CDM model the CDM stands for cold dark matter And this summarizes the properties with specter matter dark matter to have in this cosmological framework First of all, it's cold in which by which we mean it has to be It has to have been Non-relativistic at the time of structure formation It has to be dark in the sense. It has it isn't allowed to have any GSM charge meaning it's a singlet under the GSM group and it cannot make be made of Barreons and third it has to be matter in the sense of it has it is subject to gravity and It's still out there. It still forms a part of our current status of the universe and Then there has been done a lot of work presenting possible candidates for dark matter and there are here several and there are even more Candidates and I'm listing here. This is one of the most popular ones and I'm gonna concentrate on the for most of the Astro particle physicist the most popular one which are the WIMPS Which stands for a weakly interacting massive particles and the the the interesting or the attractive Property of WIMPS of these particles is that they can be generated as Thermal rallies in the sense that at some point in the early stages of the universe they were in Equilibrium from the thermal bath allowing Annihilation and creation of dark matter particles and standard model particles go in both ways However, as the universe cools down This process is and is allowed only to go in one direction meaning dark matter and lead to standard model particles But it cannot go in the other direction, but at some point the expansion of the universe grows can Balance this out and the particles and Freeze out and they remain as a thermal relic and we can see through some of the observations Mostly from the CMB and such a piece that we expect to have Density times the Hubble concert squared of 0.1 and this gives us a and Tentative target a velocity average cross section Of what would be three times ten to the minus twenty six So we have a very good production mechanism for WIMPS and we have also some target Cross-section that we can aim with our experiments to look at Now I'm gonna talk about one of the Strategies we have for making a detection in which we could claim that we have spotted dark matter and This is the indirect detection So we have many three Strategies in detecting dark matter First we have a direct detection in which we try to measure a recoil of us catering with dark matter particle within with nuclei then we have We we We hope to be able to produce these dark matter particles in in colliders And then we have the third Strategy that I'm gonna focus in this talk, which is indirect detection in which We assume dark matter to be annihilating and I want to hear a digress a little bit and say again that WIMP dark matter ensures this process this channel to be open as I said they were in equilibrium In annihilation and creation of standard model particles. So this means that dark matter can still annihilate into dark matter particles So how? We make how do we make indirect detection? So we have as I said the production of dark matter annihilating into either gauge bosons or Hickses or fermions or any standard model particle then we have the propagation of the stable particles of course if we create Hicks's is gonna decay, but then this is table particles electrons protons anti protons and Gamma rays can Propagate through the galaxy depending on the charge either in a straight line or through some complicated path and then we are Expect to detect them in the solar neighborhood or in the earth neighborhood either here at earth or in some satellites orbiting around the earth So what possible targets do we have as I said we expect you to measure some stable particles and we have first Some anti protons positrons or anti neutrons have been very popular But the issue with these particles is that they are charged and they get entangled in the Magnetic fields of the Milky Way and they are subject to diffusion which makes makes which presents of course Difficulty into pinpointing dark matter in these channels then we have Possibility of detecting the neutrinos neutrinos are not charged. They traveled in a in a in a Straight path, but they have the issue of detectability detecting neutrinos as a lot of people know It's not an easy task. I well in the end Detecting none of these particles an easy task, but you trees and neutrinos present special challenge to Experimental physicists and then we have the gamma rays which have the perhaps the The Downside that the gamma rays are a suppressed channel in a dark matter annihilation since dark matter is not charged However, they have some perks They don't diffuse and they're easily easily detectable And they can be emitted depending on the dark matter model either in a soft or a hard spectrum So I'm gonna talk a little talk about a little bit about the Methods that we have for integer indirect detection. I'm not going to go into detail I'm just going to talk about the experiments. I've been working with the data of experiments. I've been working with We have a Fermi the Fermi telescope Which is orbiting the earth which is able to detect at let's say lower high energies of 0.1 up to 300 gv. We have the earth bound Hes telescope which detects higher energies An imaging area drink of telescope which detects higher energies than them than the Fermi telescope And then the third a kind of experiment up in working on it is a next-generation telescope, which is hasn't which hasn't been Built yet, but we're hoping to get data from this experiment as soon as possible And this would be a very large experiment because it will base in the southern and northern hemisphere I need to have a broader band detecting from some tenths of gv up to one Hundred TV, so a huge energy range So I'm going to talk about as I said the two kinds of emissions that we have in gamma rays We can have diffuse emission from dark matter and elating and There the problem with the fuse emission is that it's filled with uncertainties and since the emission as you can see here this is just an example of Dark matter dark matter to BP bar and elation using this target cross-section Which is property of the of the whims and you can see it's very the background. It's huge So if we were to claim Dark matter discovery in diffuse emission we ought to have not only amazing as statistics But also have a very detailed analysis of this data in order to pinpoint Detection a flux that we are absolutely certain That it's of dark matter origin On the other hand we have spectral features and the spectral features have a nice property that they differ a Lot from a parallel background and we've been modeling the background that we have in gamma rays Mostly with with with power loss or broken power loss But this has been is it a main and it's a very it's a good approach to model the background However, if we have here, this is a lock-lock plot power law a negative power law And we were to plot over a spectral feature. This would clearly Be it is would be clear to see that it differs from a power law So it would be a lot easier to to to pinpoint an observation in in this in in this channel, however, of course the The The background is still very very large So we we also have to have a lot of statistics and a lot of of of analysis either way it presents a challenge for for us This this spiritual features have been called as a smoking gun since it would be a clear hint for dark matter as I'm trying to tell you that it differs from this power law background and Currently we have three ways of generating the smoking guns using a scenario of neutrally Electrically neutral dark matter particles and we have first of all the gamma ray lines which are the most known Features which are generated via loop We have also the internal brems trawling which is generated in when when we attach an external leg to an annihilation of Dark matter due to fermions and this produces also a bump in the end of the spectrum So and in the kinematical end of the spectrum And the third is gamma ray boxes in which I'm going to talk about from now on to the rest of my talk which are produced very easily in any casket processes in which dark matter annihilates to some intermediate state and Then these intermediate states the case in flight to okay here Showing you each in two gammas, but we may also have of course one gamma and one gauge boson or The important thing is that we have here the emission of an n-state photon So I'm going to talk very briefly about gamma ray lines This gamma ray lines as you see here we can generate this is a plotted with Flags that will be generated by Derek a loop annihilation of two dark matter particles into two Photons, however the problem with gamma ray lines is that they since they are loop generated They are suppressed by a factor alpha squared. So this This target cross-section would have for whims gets translated into a much lower Cross-section and this proves to be more challenging for experiments. This is Data that was released by the Fermi collaboration Two years ago and of course this results have improved in have been improved But still it will be long since we can get actually to this a value of 10 to the minus 30 centimeters two per second Just I'm here flashing. What's there? There's what is the status of internal Bremstrahlung? The issue here is that is since we attach A photo we have an extra coupling alpha and we have face space impression So the the the target cross-section gets also translated to a lower value and Now I want to talk to you about the gamma ray boxes, which is the highlight of my talk So I'm gonna show first to you What is the mechanism of generating these gamma ray boxes and as I said it also in the in the title of my talk We're considering task it processes. So I'm gonna consider the process in which Twitter might have particles annihilate into two intermediate states phi and then this phi decays Into a gamma ray and another particle X just for generalizing This could be also again a photon The energy of this photon in the rest frame of this phi It's just one half this parameter delta and phi which this parameter delta is given by the mass differences difference of this particle and The intermediate state phi, of course, we would have a decay of phi into two photons We would have the energy of this photon in the rest frame of this parent scalar into exactly one half The mass of the intermediate scalar However, this is not the case in cold dark matter scenarios. We assume we We assume that the dark matter is moving at non-relativistic velocities in the halo Which would mean that this particles did this dark matter particles are Addressed in the in the lab frame. However, this particles phi can be emitted with some momentum which is given by the difference of the masses of this two particles, so if We're to generalize this particle phi has to be has to have a momentum assigned to it and then if this particle phi has a Momentum then the monochromatically emitted photon in the rest room of five gets boosted and depending on the emission angle of this photon it can get a Energy added or subtracted from it So I'm very quick illustration how this works to arrive at the spectral feature So imagine we have a particle phi which is flying in the lab frame and it emits a photon So it can emit for example in the forward direction in which In relativistic in the relative in the relativistic sense it gets its energy added and so we get an energy added to They we get a maximum energy which is in a forward emitted photon. Of course we can have a Backward backwards emitted photon and this is had it's it would had its energy Substracted to it and we would have a minimum energy in which this photon can be emitted if we have if Since we have a scalar decaying this mission Can be in either there in in every direction and all of a 4 pi So it can be also for example in this direction It would have some energy between these two kinematical ends that were given by the forward or backwards Emitted photon and since we have an isotropic emission of photons from the Isotropic decay of photons from this particle Phi We would have all of this energy bins energy Values that the photo can gain equally populated and this would be give rise finally to This boxed shape spectrum, which I want to stress that I have I haven't assumed anything in the particle model In the in the in the particle physics model. So this is just any cascade decay in which the intermediate states the case into photons This would be an example of how the signal would Would arrive at earth in which we convolute with a with a with a resolution of the instrument and Depending on the velocity of the of the of the of the scalar The this took kinematical ends are different Of course if the mass of the scalar Phi is almost the same as the of the dark matter mass Then this means that the momentum of this particle Phi would be very small Which would mean that this kinematical ends are very close to this this this center and Here I'm illustrating three of the cases with I've been always Analyzing in which we've calling narrow intermediate and wide cases. So this parameter Delta is Translates them the mass difference between the dark matter particle Phi and the Dark matter particle Chi and the intermediate state Phi and In the case in which we had degenerate masses. So a very similar masses We'd have what we called a narrow case because this kinematical ends would be very close to each other and in In the case in which this width goes Below the resolution of the instrument this signal would be undistinguishable from a line But if we had different masses, we would have had to we have also we've considering to other scenarios, which we called intermediate and wide scenarios in which the the mass generality becomes larger and larger larger and larger and This box widens and widens and of course it would be it would reach a case in which This This caler Phi is pretty much massless with respect to the dark matter particle Chi And then we had a very wide box, but still we would have this right shoulder popping out So this right shoulder has a clear Shape which is not similar to a typical parallel background that we assume So regardless of which scenario we've got so without the the need of a fine tuning We'd have always some kind of hard spectrum that can be distinguished from a power law background This background I'm showing you for example is the background that we've modeled using several data from Different different sources for this different cameras or different camera Experiments that I've measured and this is just some some example of what Model would generate but this is a model that we have a model Possible background that we'd have that would look like this So we would always have a different aspect to which is different to this parallel background And I want to compare with some experimental data. We have And I want to present this in the way as upper limits so we have here two cases wide and narrow and You can believe me that the intermediate case always lies between these two and here I'm presenting as some result that we have Substructed using a sliding window profile likelihood analysis For lower energies using the Fermilat instrument and for higher energies using the Hess telescope And as you can see here if you look at the y-axis we can target a very quite low Cross-sections However, depending on the exact model We can could translate this with this WIMP the LSD average cross-section that we expect to different scales We I'm going to show afterwards, but this is just a first glimpse at how powerful this this special features can be When we want to draw limits using different data I'm gonna talk about one of the last works I've been doing I've done which in which we derived prospects on this in next generation Telescope the CTA and first I'm gonna show that the most important results. I think well the most Easy to the eye results Again, we we performed a full sliding window analysis using 300 sets of mock data Which would be expected to be measured with the CTA instrument and using this data We would be able to draw this this limits for this different cases narrow intermediate and white and white And we here I'm also showing that the sensitivity I would get in order to claim an observation detection of camera a box using the the CTA and Here I'm showing a joint limits drawn by different Experiments the Fermilat the has experiment and that the the he is CTA telescope with a different windows or window widths this this two sets of limits of withdrawn this is for for the narrow case and This limits that I'm shown here. We're drawn using the limits themselves from the Fermilat collaboration and the has collaboration and as I said before the Since the narrow boxes are indistinguishable from lines, we can easily translate this This limits drawn by by these collaborations into narrow box limits and this is a Plotting which we show a very large energy range from hundreds of from tens of TV up to hundreds of TV and we can We can cover so using this guy this boxes and with different instruments we can cover also almost two to three orders of magnitude of Upper limits for the for the thermal for the velocity averaged Cross sections now I want to go to a more Particle physics interesting part in the for the last minutes of my talk In which I'm going to talk physical realizations in which this this this Boxes this cascading case can occur So as I said what I was saying before what do we need for this gamma ray boxes to be Generated and it's quite interesting that we only need three ingredients first of all We need a stable or long lift dark matter particle, which is pretty much a given from the lambda CDM Cosmological model then we need an intermediate state Phi which couples to this dark matter particle chi and Then what we need is a sizable branching ratio from Phi into at least one for tonic state So if we have these three ingredients in any kind of model We immediately have a box and we could even forget about this second this third Ingredient About this this part of a sizable branching ratio because in the end physically we would have of course a box Regardless the size of super into ratio. However, since the background is huge we For a detection in our instruments. We need a sizable branching ratio of phi into photons So I want to show the concrete model that we called a in the our last work in which we was presented as So me years ago, and I'm sorry. I think this no this this this reference is wrong. I'm so sorry But it's in a work that we did in the year 2013 in which we had dark matter per fermion chi a scalar s in a pseudo killer a scalar a in in this model and We have three decayed a annihilation channels of dark matter annihilation in which it decays to Either a pair of a pseudo scalar and a scalar two pseudo scalars or two scalars And we have a branching ratio of the pseudo scalars into fold into two photons of depending on the details of the model of this pseudo scalar into two photons of Between 20 up to 100 percent Which is a very big branching ratio enough for for for current experiments to make a detection So how this how does this? Work this this model works in in the system Which we get a distort my republic I a complex scalar s and through the pitchy cream mechanism We can get in the end a scalar s a pseudo scalar a and we open these three annihilation channels. I was talking about just now This the masses of these particles are not Given by the model however, we can make some some some some different scenarios for example in the case of a narrow box in the case of the action is a very The mass of the action is similar to the mass of dark matter part that dark matter particle They would have a branching ratio of kai-kai into the Scalar pseudo scalar pay of almost your point nine percent and then we will in the white box case we would have a more a balanced More balanced branching ratios among these three channels, however, we will we will always have a sizable branching ratio into this intermediate states Into this intermediate pseudo scalars, which are the ones that decay in the end into two photons and we want our model to have so if we take this model for example, and we calculate what would be the Velocity average cross section today We would have we will be able to Draw this limit so these black lines are the target cross sections depending on on the dark matter particle kai on the mass of the dark matter particle and As you see with the city, I were able to exclude From very small regions to quite larger areas of our of our parameter space using and Using the using the cta telescope and these are again this target velocity average cross sections They were drawn from a physically a plausible Particle physics model So now I want to Conclude briefly and summarize what I've told you today First of all, I want to tell you that the spectral features in the gamma-ray sky would be an unequivocal signal of dark matter and there are a lot of Astroparticle physicists which which are very very Hopeful to detect dark matter in this channel and it would be very nice. We could be as a very Clear hint. However, still if it's not observed we can constrain a Lot of scenarios that would give rise to this spectral features Gamma-ray boxes are a third kind of spectral features that we add to this to the internal brain trowel and and gamma-ray lines as scenarios as As a special features and that are a very Interesting scenario a very interesting kind of special features that don't need any kind of fine-tuning don't need any kind of of of of some A Basis a values input put it by hand to work So we always have gamma-ray boxes and regardless of the of the masses of this Of this particles which would be the only thing that would ever may be fine-tuned in any case We will always have gamma-ray boxes So we will always can we can always make some claims of models that have this kind of scalar at this kind of cascade Decase There are feasible models that can produce this gamma-ray boxes and Also, there are current experiments that now exist are able to constrain the wind parameter space of some models that Give rise to this to this camera boxes So I thank you all for your attention and I'm going back to my Cam okay, thank you again for to serve you for his interest in seminar and Now we pass the round of questions and we remind you that you can be part of the discussion writing questions and answers and You can also you can ask questions via Google plus Q&A or via Twitter With the hashtag la wop So Let's now pass the round of questions. So I have a question here No, thank you. Can you hear me? Yes. Yes. Okay. Yeah in the last in the conclusions you mentioned that It doesn't matter what kind of signature it's observed you can always construct a model that Can basically describe those features? So is that is that correct or I just mean something what you said no no no what I tried to say is that Kind of the opposite way So in any model that would have this cascade Case in this case case and this sizable branching ratios into photons You would have in the end a gamma-ray box emitted So it's not that you can construct always a physical model to it But if you construct a physical model producing or having this This cascade processes you wouldn't automatically have the gamma-ray boxes. Okay. Yeah, I'm completely missing this and was the other way around So I have another question Yes So my impact I have many but anyway, and the first one is about this model that you have with actions Extract constraint that you can obtain using direct detection since action may couple also works I mean that sense with your detection Or or also not complementary with maybe some action action searches. I mean searches for action particles This this is a misunderstanding We've always been having in this model that we present using the PJ Queen mechanism we I can't actually Remind if I in today I use the word action we try to avoid it because this is not the QCD axiom This is not the action that solves this strong CP problem This is just a pseudo scale which is generated in the same way that the that the Strong CP problem action is generated, but this action doesn't couple with with with quarks. So this is trying to measure a Coupling directly with the action with quarks. It wouldn't be fruitful Thank you and our extra question just just by curiosity if you're I mean in your model you have the Fee field that is a scalar, but in principle you also can construct modeling Which you have fermions or vector like the intermediate the state? Yes, I would expect that also you can add some extra Apart to the box you have some all their energy distribution that are not boxed because some momentum are in the In the in the expression, I don't know Yes, indeed Let me share again my screen. I have a backup slide for that So of course this intermediate state can be Not a dozen to be a scalar Let me go share and So Okay, so in the case in which we had a fermion we would have some preferred Emission in the in the in the in the in the rest frame So in the rest frame, of course, this this decay wouldn't be Isotropic and here I am showing you only the case in which let's say once this part intermediate particle now a fermion boost it Suppose the preferred emission is in the forward direction Regardless of how is it done? So we would have a Main emission in the forward direction and less in the backward direction. So this higher energy values would be larger populated than the lower energy The lower energy values So what this would mean is that in the end if we would have any kind of Preferred a emission direction of emission would have this this slope would be tilting Between this and then of course you would have a background a background Emission would have a negative slope and we would have Again this this kind of shape it because the slower energy values would be larger populated than the larger energy values, but still We've been working with this and both cases. So this this one clearly again keeps a heart a heart Sphere from the has a it has a car cut off and in this scenario Although it doesn't look like if we would to analyze with a current background that we have It would still be distinguishable from a parallel background because this is a and it's not a log log plot This is a linear linear plot So if you would by I try to plot and a parallel here, you would still be able to distinguish it from the from the parallel Okay, thank you Okay, sorry So I have a couple of questions also So you addressed I could be a firm in our scalar, but what about psi? What about the dark matter? How do how do things change if you assume that your dark matter is a scalar in the models that we've been working on we would Having with a house consider dark matter being a fermion. So either in, Majorana or dirac fermion in both cases We you get the the mission the issue is that we the is not it's not influenced by the By the angular distribution of this intermediate state, so This is a means even intermediate states will be a me emitted With a different angular spectrum, but still due to kinematical reasons. They will still be Generated with with active momentum. So if you add to scalars annihilating, let's say in some particle physics model to Either fermions or either or scalars The thing that we that we need is that these intermediate states are emitted With either with a momentum or without a momentum, but in for our narrow or a wide Box, but it wouldn't change So if you have a model with scalar Dark matter dark matter that has this cascade Behavior and then again a decay into into photons a sizable decay into photons You would still have boxes all right, okay, so a follow it following that going back to To Phi so in order for it to to couple to to to photons It either needs to be charged or it must couple to to some sort of charged particle, right? So then the immediate question is if they can be produced at the LHC and if current searches could give bounds on the mass of Phi or something like this the usual Methods that we the methods the usual the particle physics models that we considered have had this this this decay from It is decaying being produced via anomaly So this is indeed a pseudo scalar as an as the axiom which is a case via anomalies into to photons and again into to to Also to to vector bosons w's and z's However, we haven't considered the possibility of this this particles being produced these actions this pseudo scalars Sorry, I don't want to use the word axiom because it leads to me misunderstanding This pseudo scalars in this specific case to be produced at the LHC But we haven't considered How the LHC status is with respect to this So when you say anomalies you mean you just specify an operator and and that's it, right? You don't assume the virtual particles in in the In our case of the future particles are our Star model fermions Okay, okay. Okay. Thank you. Okay. There are more questions on the Q&A. So There are three questions of Roberto, which I think Been asked. Is that correct Roberto? Yes, correct Yes, and okay. So now if there are no more questions, I'll pass to the Q&A Questions. There's a question from Oscar Macias. I was wondering Can you get a boxed spectra from a well-motivated theoretical model like? a supersymmetric model for instance Well indeed, I I I shown that this this model that we worked in in which is a well-motivated model and The the the other model that we also consider is a model that was proposed in 2008 by no more on sailor which also gives rises to the To to dark matter particles. I actually have a slide which summarizes that model Just to not to discuss on it just to present it Let me see if I can Get it fast enough You have to share your yes. Yes, I was searching for the for for the slide. I have it now let me share again my screen and In this particle physics model done by the modern tailor In this reference they actually generate this this in area is very similar to the one I Proposed and they have you one symmetry and use a pitch equine mechanism in this scenario However, they were they were trying initially to reproduce the the the Pamela electron positron Excesses and then in this particle they actually considered a lot of data and they settled a Particle fix more physics model in which the dark matter particle has a mass of one TV and the axion is very very light due to some other Elements other observational Limits so in this case we would have a white box, but this is another theoretically motivated a model that would be Would generate these boxes Okay Think there's another question from Abelino Vicente, what about the decay length of the five fields? Does it play any role in this game in particular would a long decay length have any impacts on the box properties? um So the the the decay length of the in the in the in the limits I I showed the decay length was is is is quite small in in galactic Scales, so we we don't expect that this fight to propagate far from them From the from the origin of this particle fire However, if we had let's say a longer lift particle in which this this decay length still lies Below the the the ten or five or ten kilo parsecs, and you this means that this particle would still decay inside the galaxy and The shape of the of the box would be the same so the if we would have the flux with the with With the with energy however, of course the detection the map the sky map that we will see From these boxes wouldn't be exactly the one coming from the from the from the profile we're considering So for for example, if most of these particles five are produced using Casp profile in the in galactic center and these particles can of course since they're not charged They can drift out from the galactic center. We would see a larger flux Coming from higher latitudes and longer larger high Latitudes and longitudes Than the city than the center itself, but the shape the spectrum the energy spectrum of the of the Of the box would be the same regardless of the decay length of the of the particle fire Of course, if it's stable, then you wouldn't have any any any boxes Because it would decay Okay, thanks. Um, I have a question in the case. Oh, hello Can you hear me? Yes? Yes. Yes In the case where you have a very narrow box um um Don't you have corrections say from a third emission of an emission of a third soft photon which would Change the shape of that box Could you repeat that? Yeah in the case where you have a very narrow box um There I expect the intermediate particle to be fast, right? Um exactly and in this case you would have Corrections from the emission of a third slow slow. Sorry slow. Sorry slow slow. Yes for an arrow case You expect the momentum of intermediate states to be low And in that case it would mean it would mean this would mean that the energy that the particle gets added Uh Okay, thank you. Yes. I misunderstood. Okay, there's there's another question From one of us. I don't know. Yeah Who it says does dark matter particle Psy need to be a fermion Uh, sorry, that that was me. I already asked a question. Oh, okay. Okay. Yeah, you were signed as statin america. Okay I made a mistake. I'm sorry. So I think I have one one more is just What I mean, if you have considered the case in which your five field is Electrically charged in the sense that now it can also have Bremstrahloom by itself plus the decay of Maybe a full Oh If the particle would be uh charged then of course you would completely destroy the the boxes because you would have A diffusion where you have energy losses and you will emit of course synchrotron radiation and Different kinds of radiation, but again when this particle decays into photons Since they this particles would get Randomly entangled in the in the in the in the magnetic fields. You wouldn't have such a clear Uh, let's say it's such a clear Status of the particle phi at the moment of the decay you would have this particle phi after the whole energy losses with different energies with different directions of the momentum And you wouldn't be able to claim these clear kinematical edges that I was explaining before Thank you Okay, so if there are no I don't know. I don't see any more questions So thanks again to Sergio for his interesting talk and to all of our viewers And okay, let's um remind you that we'll meet again in I think two weeks for another webinar in physics