welcome to the science for the public lecture series science for the public is an organization committed to bringing science information issues to the general public this is our website for our program good evening i mean step for science for the public and i welcome you to tonight's contemporary science program our guest is to leak a bull's assistant professor of physics at boston university and a member of the great international team of scientists preparing for the reboot of the large hadron collider at cern in two thousand and fifteen dr both received her ph d in experimental high energy physics from columbia university in two s experiment at the cern large hadron collider both of the she will discuss tonight she's also worked extensively on trigger and data acquisition for both the d z role and for the c m s and is currently serving as the trigger coordinator at the c m s experiment another task explained the night dr bowles has received already in her career a number of prestigious awards including the fermilab twenty fourteen c m s distinguished research or award and a twenty twelve alford piece long research fellowship awarded to the most promising of young scientists she's produced numerous publications and ranking journals in is actively involved in searches for new physics using data collected by the c m s it is a very great pleasure to welcome dr balls ok let's start if you would give us a little background on the l h c in general catch us up so to speak first of all then why is such a massive machine the biggest i think in history necessary to collide little tiny things ok so i actually like to start with an analogy suppose you are interested you have a nice watch and you want to see what's inside you want to understand how it works you get a if something actually different rather that we have we collide protons with protons and when these protons collide they disintegrate and in the mess that comes out there are a whole bunch of new particles and it's somewhat ball and out of it comes basketballs baseballs footballs all sorts of wonderful things come out a fit and so when this mess that's coming out we see essentially the energy of that is that what went again coming out of mass of the stakes as do einstein's famous equation easy call to mc square the more energy you put in the more mass you can create now the particles we're interested in are so very very rare that you really need again a lot of energy to be able to increase the probability of finding a rare particle and so we try to push higher and higher an energy such that we can discover new particles that have not been discovered so far ok so and that's the only way to get at these particles is that it i mean this is this is one of the ways right other way you could think of is this is by you know this is like a big hammer good yang right getting about the other way of looking at something would be perhaps going lower in energy but looking more closely and doing precision measurements and observing what comes out of it so in that case you don't need to go over a very massive machine you could have a smaller machine so what we have found is the kind of physics we want to do the kind of energies we want to push proton proton machine gives you access to a very large range in mass and that was one of the the design principles th experiments in the sense that they do a wide variety of particle physics including heavy iron physics including beat work physics but the main emphasis of these experiments has been over the last few years search for the so called her expose on search for a new particles and here are the two experiments have the same sort of physics in mind but they were built with different technology and that is why two experiments were created so you could go after the same terms of the great accomplishment of twenty twelve of confirming the higgs what does that signify in general also of in terms of the implications for future research those two things with what about the higgs i think again i'd like to start with an analogy to sort of first talk about you know what is that yes they have right so what i find  to borrow from actually a set of cartoons that were that were written by david miller from u c a london the u k science minister put out a challenge asking for cartoons or anything to explain the hi bar and the the prize was going to be a bottle of champagne so david miller went and he came up with these sort of questions and they're beautiful because you can really explain it in just you know three cartoons so imagine you have a room full of people there at a party a cocktail party and very famous person comes in through the door and as the person walks in people start clustering around this famous person because they want to talk to him or her and the person wants to go to the other end of the room but they're unable to go because they're being stopped by these groups of people so it's almost as if that this the fact that they are growing more and more slowly it seems like they have acquired more mass you know massive particles  and this person is being stopped and is not going so they're interacting more with the people as a result of which they seem to have acquired mass so higher the interaction larger the mass on the other hand if a completely or relatively unknown person walks in nobody wants to talk to them they can go from one end of the room to the other no interaction no mass they don't seem to have but you don't at all so this was the idea that those people in the room is  and how a particle interacts with the higgs field determines this mass if it does not interact it's massless if it interacts it's got mass how much you didn't rocks determines how heavy it's mass coming into the room but the fact that people near the door have heard this rumor they start talking about it then this goes on to the central part of the room and then to the other part of the room so again there is a clump or a mass of people who are passing this so for the last fifty years we've been wanting to find those higgs bosun so that we can prove that the higgs field therefore must exist and is responsible for giving master particle is it also responsible for the differences in higgs we try to hunt for the higgs in different ways and in the main sense that the higgs can decay into different particles and if we measured the higgs and its properties and all of these different decays we can sort of test is direction in different kinds of partners and here in comes the fact that the standard model which is this our is an elegant set of equations which sort of describe all of particle physics it has certain expectations for what which would really be a big deal for some of these people who've been working on supersymmetry for a long time exactly yes this is the big sort of goal yeah our next run is exactly to go and measure very very precisely the higgs properties such that couple of things about that age seem just in general uses a lot of energy that's one thing and it produces a lot of data so could we go to the energy first can you give us a clue here about this at certain specific points and those points are where the detectors are situated now what is the energy of these protons these stepwise acceleration back when we first started the other see the first part of the run one each proton had an energy off three point five t v or trillion electron volts and so you had three point five three point five the total energy of the collision that was available was seventy the following year the increase is a little bit so you have fourteen colliding head on with forty three and you had a t v of center of mass energy next year when we restart this is going to increase even further and the expectation is the exact and run one so the kind of physics that we should have access to it opens up an entire new regime essentially right is that is that the maximum to even fall for the l h c so the design is around a take can you give us an idea of how much energy it takes a while i mean in terms of you know the every accelerator that we're doing right you have various steps and you're trying to  cost of running at the power was just prohibit and you just couldn't do it and they would run only during periods where these this was manageable so yes it's a costly enterprise to do that and it is a drain on resources but  again the technology is such that you're able to do it i mean you know thirty years ago nobody had imagined that we would be able to do i have collisions at close to you know fourteen t field in order to have the kind of bending we want these need to be very big magnets providing a high big net it feels and that can be only done by superconducting magnets now superconductor is something which you know below a certain temperature essentially allows you know a lot of courage to go without any resistance and in order to be that sort of temperature it needs to be kept cool and that's where the liquid helium comes in because it allows essentially all of the superconducting technology that we use of the ologist sea to be kept at the kind of temperatures that we want and because if they're not then they can no longer be superconducting and that means we no longer will be able to have the kind of bending that to know another thing is the level of data the amount of data that this is collecting it must have people all over the world certainly about where to put  you gave me an idea of what this data help big this data tell us about it right so the data that we end the bright and just sort of simple terms if you were to pile sort of you know tapes or discontinuing this data on top money we have for the kind of tapes and desist letter where we write out all of this to allows us to write our data only of the order of a few hundred so we're going from the initial production after the to only about a few hundred that so you have a selection process absolutely this selection we call is the trigger this is the part that i work hard and the trigger runs online and it's every twenty five nanosecond just looking at the data it's event look interesting to keep or should i throw it away and if it's interesting to keep you keep it and you push it down the pipeline if it's not interesting you threw it away right away and we have a complicated is a multi tiered trigger system which works with the kind of information and time it's happening real time is zero you have initially of the order of microseconds to make a decision then at that later on level you may have maybe a hundred milliseconds and  this period of time you have to decide that you're going to keep some amount of data and keep in mind that the data that you're saying no to is literally going into the trash or you will never ever think so if you don't design your trigger well  higgs or your new particles may be in the trash and you may not be writing it out so you have to be very very careful that a huge responsibility that would keep you up and keep you up and so let's go to this this is where your work is centered so in the start up period first of all just that that you have to be so very careful about that can you give us an idea of h if i don't find anything interesting let's throw it away so we have to design and put an end to the hardware into the electronics design some of these algorithms which make very coarse decisions do i see an electron do i see a new one does it have certain momentum which i expect an interesting particle such as the higgs particle so we use our current knowledge of physics and what we think it should be like to make some of these selection criteria and then this level one trigger has about a few microseconds to make a decision it's then decides and it gets this forty megahertz down to about one hundred killers and it's sensitive to a form of computers these form of computers now because they get only because now they can ask for not just an electron but perhaps the charger for the electron for example so they can look at more characteristics make more complicated decisions and ultimately whether the result of that as long as the event has satisfied certain interesting yes is it possible to sort of predict what think you might find you're looking for surprises but it seems so scary with throwing out a lot of it yeah that is that is the biggest challenge right that we have certain ideas you know theory from our understanding that ok if this is going to be a particle you know for the higgs it was easier because i guess you know it was predicted we knew what sort of properties  so we could trigger on it or design algorithms to selected it in an easier way but this other new physics that could potentially be out there we don't really know what it is we are i'd take certain guesses that ok we would which will produce particles which have high momentum so we use some common sense some knowledge of theory or understanding of the world and how things work to design these triggers that we have to keep an open mind because it could be exam thing completely triggers which may be more general but we write out only a small amount of those with the hope that if new physics were to come in this sort of a category we might see a hint and then we can go and redesign our trigger strategy to start to focus on that m s i talked about as a tool that atlas has a different system which does it in three ways now certain things are common and we're actually for going on the same kind of physics a known physics but yes you could you know if we don't do a good job it's possible that you know one experiment sees it and the other i was just going to say it's another way and then at the same time you're overlapping important money guard so that you can check exactly unfairly because i mean if both experiments because you're so similar if you were to find something new physics in a way you would expect that the other experiment would also see the signal maybe not to the same intensity but still see something here that's a very good cross trick to have another sort of answer it tell us some of the main sort of new physics we're looking at one is this our model which has been around a long time which we record to is super symmetry which essentially predicts that for every standard model particle there is a partner particle and and it helps to solve some of what we call things we don't understand about the saturn model one other thing it helps to do is this the fact that you know what we understand the universe today is really about five percent ye for explaining you know dark matter it has a so called l s p light and super symmetric particle which could be a dark matter candidate so this is why a lot of people are interested in finding out or  category is broadly speaking what i call exotic models and they are our whole slew of them and many of them predict for example so if you could call them your brothers sisters cousins of the standard model particles or for example there is a really allows us access to much more heavily in the meantime particles and we've ever had access to and we can look at the w prime particle not just ticking in one way but decaying in many ways because again we don't know that in this new physics which may be correct that it decays in a certain way so what we try to do is we try to cover all our tracks and really look for it decaying in all sorts of possible ways and so that's been one of my focuses is looking for such a particle and then there is another similar particle which again is very well motivated theoretically is partner to the top work now we have six quarks in the standard model up down strange to bottom it's in fact the heaviest particle that we've seen because it's one seventy four g b the higgs is one hundred twenty five now why is the top quark so heavy ok perhaps once we understand fully the higgs and it's probably is we may be able to understand that but the fact that it's heavy leads us to think that if there is a new heavy particle out there there's a good chance it may decay to a top part it may either decay to a top or that there may be an you could have a heavy top partner which has some properties that are common to the top quark and some which may be different so that's again one of those things that i have been searching for hoping might turn up in later years is there have a charge there might be a singer charge plus one or minus one and so a lot of interesting studies and research projects are going on which are designed at figuring out if perhaps what we might see might be a these things out there keep bumping into more and more particles all the time but in this case it's all very exciting ok let's go to your research specifically the areas you've already mentioned this i want to make sure we cover the exotica stuff too the pose there was a doubly prime partner going there it would decay into electron for example and this electron would be one t v to t v so we wrote some algorithms which would in this express stream data look for the lives of prime incidents such that we would know immediately within hours of data taking that we're starting to see something and then we can really you know get our act together and be so we wouldn't wait because since we're collecting so much data analyzing it takes time that's what i understand and so this is just a power path where we look at a subset but a subset with extreme characteristics which we expect that these heavy particles will have it seems an advantage that it's a small group entirely focused on this is i mean yes to begin with because you know you have to you know think of what the ideas are it's sort of it's also for me it was really nice everything here so we are now that it's you know we understand it and it's you know it's worked out very well and run one we're extending it to run two we hope that more people will join the sefer to sort of try and make sure we get the new physics as soon as it's there right now in this time that you've got this experience from twenty twelve your veterans now and so on but this sounds like it could be really new really unexpected at this energy but you've pointed out that it takes a long time to scrutinize this data that after all this selection of the trigger and stuff do you think it will work faster took a long while to confirm the higgs for example they were very careful with what to expect in terms of confirming finding and confirming so i mean i think firstly there is always some discovery for example if any of these new exotic particles are just around the corner they should appear right away but this is just as this big jump in energy gives us this huge boost so we wouldn't need to wait for you know years and years for th s so new heavy particles should appear in the first couple of years of data taking is what we are what i hope yes and of course you know in the time from when you start seeing it to when you're ready to go out in public to claim it  now is is is a little bit because you know we want to make sure that we are not making a mistake or the lady experience in the past exam and so it's very very very important for us to be careful so unless we've had you know multiple analysis teams looking at the same data coming out with the same conclusion we wouldn't just because you know two people saw exactly what it says ok any analysis especially any high profile analysis for it to be made public essentially goes through a very making sure you're not making a mistake everything is as exactly what it should be and doing billions of cross checks and so this is where if it was a strange new particle you could have more other kinds of new physics for example you know standard model has certain predictions for rates of certain processes and there are some processes which are very rare which have very low rates now they could be a new physics model which predicts enhancement in the street in order to actually see that you need to collect lots and lots of data to be at that level where you could be potentially seeing if there is a discrepancy in this very low rate process so for that you need are sure a really find professor as well do you are students very encouraged in this time i can't imagine a better time to be in this joining this field now i mean i think this is an amazing time i know are for example for our graduate students they are completely you know i mean i mean we have already had a number of students start you know coming to be you because they want to be partners because they're seeing that it's definitely something that's on their mind not just that for example right now i'm actually teaching electricity and magnetism to a large group of engineers and i use a lot of my image see work in my sort of lecture about syria because the point is we are making use of electricity and magnetism and they are  engineers build this thing and that's it's just just an astounding accomplishment dr bose you have also tried to promote funding for science i think you're involved fermilab with something like that would you please tell us about because this is important for this organization to support funding for science yes i mean that is a very very big deal because as you see what we have are these amazing detectors and  but they have very very complicated they lead large numbers of people to make them work and if we don't have these people these machines will not work now so what i'm doing i'm part of the fermilab uses executive committee and part of our job is to you know do outreach to tell people the kind of work we do what its benefits to society are and also to for example go to washington d c and talk with people on and congress in the senate and again you know tell them look this is the work we're doing and there are two things this international this is international is huge you know collaboration's worldwide there is something we're doing and fundamental science which is helping us understand nature and you know we know for a fact that w have today or what is coming out of our work today may very well launch a revolution hundred years ago hundred years from now i mean for example what we're seeing what is coming now you know semiconductors superconductors all of this work came out of so all of this has come out of the fact of fundamental science and so the fact that we need this to happen means we need support for this funding for this and that's why having the public on board with what we doing and it's value to society to us or the world or the community in general is very important in order to get support from the funding sources is there kind of unity of support in say the europeans other nations many nations are involved in this project at cern or is there less difficulty getting the funding in other countries or i think it depends probably from country to country and some countries are doing better than others but they do tend to work for example a lot of the your european countries because they're part of the sun council and they do have some isn't in the system right brings the we are local alge yeah right it's a challenging time from everywhere in the world but certainly you know some countries are doing better you know japan our example is leaving for what very soon run perhaps in the next year or so with a new collider yeah and that would yeah the next you know sort of step right and they seem to that we can't possibly have one in each country rises these will have to be international collaboration so yes we will need to collaborate with each other you know we could have something big here people come here we have something big in europe we sell at cern we go there and it's  location for this big neutrino experiment that will start up in the next twenty to ten to twenty years and that would be the central place then that people from all over the world would then adverbial and work right neutrino right there's a gre stand by this whole project it's certainly garnered a huge interest of the film particle fever was very popular despite limited distribution and so on and so i wish you all the i grew up in india number of places in india actually because my family moved around we were in calcutta and delhi and whole ball so i did my early education in india i went to college in delhi delhi university since stephen's college and then i got a scholarship to go to cambridge university in england for my undergraduate so i did my physics undergraduate degree from there and then came to the us ninety ninety eight for grad school at columbia and my father was a political scientist my mother did literature so there was nobody around me doing physics there was a lot of emphasis in science education engineering medicine all of these had sort of actually in in cambridge in england when i did an undergraduate thesis this was about time an experiment was that suddenly it was a precursor to the l h see this was the opal experiment and it was when i was doing project that i was thrown into this world of particle physics and at the same time in the us very exciting discovery happened at the fermi lab tevatron this was the discovery of the top quark this was ninety ninety four so i knew this was  really i'm back in england and i'm here i have to go to the us because i want to be part of that team that discovered the top quark and and i came here i did a small research project on the discovery of the top quark and then got heavily involved since then there are two main areas i am currently serving as what's called the trigger coordinator of the c m s experiment which means that i have to make sure that we collect data the data that we to to use to discover new particles and physics in a way because we collect lots and lots of data at the alleged see this is huge amounts but how much of it is relevant for the kind of physics we want to do that decision actually has to be made online closer to the rather i'm going to go back there and i'm going to be again based there for about a year and