How do you detect a neutrino?

[@papa_xan]

I called my work and told them I quit because I'm now a neutrino detection expert. They were surprisingly unimpressed.

[@tabaks]

@Papa Xan, get used to it. No one here is impressed, either.

[@constpegasus]

Papa Xan I believe you. Waiting for your book to come out.

[@michaelsommers2356]

If they aren't impressed, just oscillate into another kind of expert.

[@bogadu]

According to the Heisenberg uncertainty principle it is extremely unlikely to be impressed by this….. but not impossible.

[@mdunkman]

I got my PhD measuring neutrino oscillation parameters a fee years ago; the job market is very tough. I’d strongly recommend other careers.

[@andrei-un3yr]

If I had someone to explain physics to me like dr Don, I would have most likely picked a career in physics. I can only imagine how many people like me, because of poor quality education in school, didn't have the chance to discover what they like.

[@chrisfromsouthaus2735]

My youngest brother must be a neutrino. He very rarely interacts.

[@Ii-fo8pq]

😂😂

[@marinojames8564]

Ik someone who’s in the same situation as you lol

[@x_gosie]

Your brother is autistic.

[@static7793]

@@x_gosie wha- dude...

[@dougroling7303]

Ba doo pa 👏⚡️🌟

[@nathanrocks2562]

This channel has immense replay value. 👍

[@QDWhite]

Virtual particle: High five! Real particle: Nah Virtual particle: Oh, uh...that’s cool. *disappears in shame*

[@edmund3504]

every time I watch your videos, I get more and more excited to learn more about physics. I can't wait to start college in the fall. keep the videos coming Doc!

[@Trident_Euclid]

Good luck in your studies.

[@johnopalko5223]

He says, dismissively, "It's an E=mc^2 kind of thing." You gotta love physicists.

[@filthyfilter2798]

Very nice and simplified explanation plus amazing illustrations! Please keep it going! You are amongst my teachers

[@thiagoabsc]

As always, great video. Please, never Stopp with this initiative!

[@joshuaentwistle960]

I have a question... did anyone remember Uli's goodbye cake? Good work, Dr Don!

[@mazelme]

Seriously Dr. Lincoln... Don't forget Uli's goodbye cake: 2:30pm. You!! Totally!! Rock!!

[@yootoob6003]

wtf

[@mazelme]

@@yootoob6003 Read the black board ... :)

[@AdityaKadamMechanical]

Thank you Fermilab team for the explanation. India is constructing neutrino detecting laboratory in South India with worlds largest magnet times larger than CERN, Switzerland❤️ ❤️ ❤️ ❤️ ❤️

[@joshfarch172]

why are we giving you aid then

[@AdityaKadamMechanical]

@@joshfarch172 If your govt. is providing any aid, stop the aid. Anyways for Indias GDP & population few million dollars is negligible :)

[@kateri17]

@@joshfarch172 what a stupid and crass thing to say.

[@paulmichaelfreedman8334]

What blows my mind is that a neutrino with a mass of a few electronvolts can emit a particle with more than 1,000,000,000 times it's own mass.

[@tanmoydutta5846]

That's particle physics and Quantum weirdness ,dude

[@paulmichaelfreedman8334]

@@tanmoydutta5846 Du-uh!

[@paulmichaelfreedman8334]

@Scott I think i got it now, the neutrino emits a very light weak boson, one of those extremely rare ones, which then smashes a nucleus.

[@paulmichaelfreedman8334]

@@jitteryjet7525 in the explanation Dr. Don does not say that it emits a virtual particle. It emits a real particle. Furthermore, I'm not sure virtual particles can smash anything. Because it's virtual, it's not actually there.

[@drdon5205]

Yes, the particle is virtual. Most virtual particles don't interact, but some do. This is one of those cases.

[@sethapex9670]

Why doesn't fermilab coordinate with the Icecube observatory to conduct some neutrino experiments? It's further away and passes deeper through the earth so it would make an excellent opportunity to measure how those differences affect the neutrinos.

[@michaelglynn2638]

I'm not qualified to comment on such matters, but that was both fascinating and understandable! Thank you.

[@bogadu]

@@stevenutter3614 lol! As we white People tend to put it, - you, sir, are correct in that assssement.

[@azurlake]

The hard part for me to understand is also how to tell that the detected spray corresponds to an actual neutrino interaction, and not anything else that can be happening in or outside the detector. For instance, a random atom decay, or an energetic ray that made it into the detectors and broke apart other particles. I get the energy footprint is different, the decay times are different... but it's got to be a complete mess to tell one thing from another.

[@paulmichaelfreedman8334]

I don't know the answer either but that's the hard part of particle science. Detecting isn't hard, it's distinguishing between the different kinds of collisions that the various particles undergo and telling which is which. Normally the theories predict a certain outcome in a certain situation and that's what you look for.

[@michaelsommers2356]

_"... but it's got to be a complete mess to tell one thing from another."_ That's what the massive detectors, their associated electronics, and the massive computers are for. I can't tell you how this experiment works, but I can describe a simpler experiment I worked on as an undergrad. The basic principles are the same. We shot a beam of heavy ions at a target in a magnetic field. The ions would hit a nucleus in the target, exciting it. The target nucleus would recoil, and as it did so it would also precess, due to the magnetic field, and then decay, emitting a gamma ray. We had four gamma ray detectors arranged around the target, and a particle detector to detect the incoming ion as it bounced back from the collision. The electronics were set up so that we only accepted events in which the gamma was detected within a certain time after the recoiling ion was detected. Because of that coincidence window, stray gammas or stray particles would not be recorded. Of course, it might happen that a stray gamma and stray particle would arrive at the same time, but that would happen so infrequently that it would not affect the results.

[@danielogrady6086]

@@michaelsommers2356 Thanks for the reply! I get the idea, but the fact that in this other experiment it is neutrinos that we're dealing with, and there are billions of neutrinos going and coming from everywhere and passing through every square meter every second (and also the fact that they are much less understood that plain atoms or ions), must make it very difficult to have all the variables that controlled. For instance, I guess you cannot expect to have a neutrino bouncing off a particle and ALSO being detected by some electronic device within a timeframe to discard other events. In practice, there is no way to see a neutrino, so the footprint a netrino collision leaves must be rescued out from all that big "mess" in a much less controlled environment... after all we are talking about a big pool of water, which may contain DO2 and TO2 in very small quantities but causing random decays, and traces of other metals that may randomly decay, and there's also the fact that the interaction products must be able to make it to the detectors before being absorbed and/or transformed into something else, making it even more difficult to tell what the original interaction was. It's just mind blowing.

[@paulmichaelson7203]

Dr. Don, you may be looking a bit gray these days but your videos are as fascinating as they have always been. I love neutrinos and your videos!

[@drdon5205]

DrDon has been gray for a long time. It's called distinguished and gravitas.

[@deanbuss1678]

Just stumbled on your channel ! I barely graduated high school, yet I , for the first time, can actually understand and internalize you teaching. Thanks 😁

[@battleforevermore]

How do you detect a neutrino? You don't, neutrino detects you.

[@MikeRosoftJH]

And it's pretty bad at detecting you (or anything else for that matter).

[@justagenosfan]

@@MikeRosoftJH grandpatrino

[@JAKOB1977]

Thx Don simply perfect, just what I needed for my CV 8:55 [Neutrino Detection Expert] or NDE for short' signed by Dr. Lincoln from Fermilab. Remember Don, my name is Jakob if somebody rings you and wanna validate my CV claim.

[@GottgleicherMaster]

Great video, as always. But 300° F?? Why not use Kelvin, like it is common in a scientific context?

[@m.i.qurashi2456]

I was thinking the same thing

[@DDKKAY]

422.039 Kelvin...

[@suokkos]

It was -300°F which would be 87°K if they have Argon in atmospheric pressure.

[@Allan_aka_RocKITEman]

I think he used degrees Fahrenheit because more people recognize that than Kelvin.

[@SicilianDefence]

Thank you Don! Awesome video as always

[@PanglossDr]

Thanks for that. I saw one of your other videos yesterday and had made a note to myself to lookup 'how on earth do you detect neutrinos'.

[@פרויקטפאראדיי]

Could you please make it possible to add subtitles/CC to your videos? It's easy thing to do, I am sure you'll figure that out. It would make your channel more accessible to those who their native tongue isn't English. I add subtitles & cc in Hebrew to many science/math related videos on KZbin, and as a physics-math student, I find your videos as high-quality and quite informative. Making it possible to add foreign language CC/subtitles to your videos would benefit your channel in the long run, as it would increase the exposure to non-native English speakers countries. Other than that, I found your video quite accurate & enjoyable to watch. Keep up with your good work!

[@billzhang575]

Such a great video, this is similar to the other Weak Force Video.

[@johnmcnaught7453]

Great job Doc ! I watch all your presentations, and I think this was one I could follow from start to finish without getting a headache. Now that I'm an expert, how about a job. Have slide rule, will travel. (Remember sliderules ?)

[@Eyerleth]

Is "-ish" now an SI approved suffix?

[@suokkos]

It sounds more like imperial suffix. The video happened to use Fahrenheit too.

[@inyobill]

Statistical/Probabilistic Maths concept roughly interpreted into informal English.

[@rakas_kone]

Yes

[@averagemilffan]

Yes-ish

[@Someguyorgirlfulness]

This corner of the internet has provided me more goodness than I expected.

[@adsjar]

Thanks for the wonderful video. While you have to use fahrenheit for the US audience, your 224K subscribers include folks from around the world who use celsius. Would be nice to have a text showing equivalent in celsius or even kelvin.

[@LucenProject]

2:20 Super easy, barely an inconvenience!

[@ShenLong33]

Why is it that whenever a neutrino is near a nucleus of an atom if splits? BUT, I think the most important question is: How do you know that when the nucleus of an atom is destroyed it is by the mechanism you are describing? I mean, is there no other way the nucleus would be broken? Because if there is another mechanism by other particles, then you are not sure if it was caused by a neutrino passing by. Love the videos. Please keep on this work. I think it is REALLY important.

[@KohuGaly]

The collision products match what we expect to see from a neutrino with particular energy coming from particular direction. It could technically be something else, but Occam's razor suggests otherwise. In fact, you can go about it the other way around - define a neutrino as whatever causes these effects and then try to figure out its properties. That's how electrons are defined.

[@spartanRS1]

Fermilab is everything!

[@nileshkulkarni6196]

can you make a video on evanescent waves along with explanation for quantum tunneling ?

[@nileshkulkarni6196]

please

[@tscoffey1]

So neutrinos are detected by looking for the residue particles that occur when the neutrino emits a w/z boson, and that boson hits the nucleus of an atom. But how do you know that it was indeed a w/z boson that struck the nucleus (as opposed to another particle) in the first place? Is it in the way it scatters the particles? Or because at the energy levels involved, it could only be a w/z boson (and thus, from a neutrino)?

[@AwnSight]

I think someone is making this up for grant money

[@AwnSight]

It's like saying I threw a rock into a creek but only hit oxygen particles. Now I'm wondering how bombs actually work

[@Valdagast]

It blows my mind that we can even detect these things. Since W and Z bosons have mass they can't travel at the speed of light. Do we know how fast they typically travel?

[@Pankajkumar-el7kv]

Very near to 'c' ......rumor was that the travel faster than light ......but its clear now they cant beat photon unless photon is in dense medium.

[@onehitpick9758]

@@Pankajkumar-el7kv That was a wiring/connection problem. They never, supposedly, traveled faster than light.

[@rogermoore7293]

Just like everything else it depends on how much kinetic energy they have. You can create them at rest so they do not move at all which is what the LEP collider at CERN used to do.

[@onehitpick9758]

@@rogermoore7293 This is nonsense. Neutrinos have incredibly low masses. Even thermal neutrons (much, much, much more massive) move at incredibly high speeds. A neutrino created in reality must be moving at close to (but not equal to) the speed of light.

[@ABaumstumpf]

@@onehitpick9758 ?? No? The velocity of these particles can vary greatly. Most solar neutrinos reaching earth are under 10eV, many under 1eV which gives them a speed that is just a fraction of the speed of light. They can be as slow as just a couple thousands km/s.

[@aharinparvin]

Fermi lab! You are superb !!!!

[@spiderjuice9874]

Interesting that the W/Z bosons operate by the weak force but they still can overcome the strong force when smashing the nucleus. Any further explanation along these lines would be welcome!

[@hemlio7082]

This is best channel ❤❤ after pbs space time and astrum

[@tresajessygeorge210]

THANK YOU... PROF. DR. LINCOLN...!!!

[@hopp2184]

8:42 300 Fahrenheit below 0... please use SI units when speaking about science to avoid misunderstandings like the crashing of that mars rover.

[@balazsszoke9107]

Hopp live long metric system

[@pansepot1490]

Hopp, I know but he must make his videos accessible to the dumb American audience. 😂

[@funkyflames7430]

@@pansepot1490 Very smart commenting on a country you know little about. Considering that the Fermilab is in America, I think it is natural for him to use AMERICAN UNITS. That's right, we named our system after us. THE AMERICAN SYSTEM! Anyways, it isn't nice to say such a thing.

[@nafrost2787]

I use metric, but I don't have problem with the host using the imperial system, a writing of the value on metric is enough for me.

[@HallsteinI]

@@funkyflames7430 Don't get all worked up bud, scientists use metric.

[@TomHendricksMusea]

REVISED VERSION (psy phy physics from a sci fi writer.) The student of physics can write how photons made the entire universe in FIVE LINES of script! Background: My suggestion is that soon after the Big Bang Photons produced electron and positron pairs of waves 1. The ELECTRON wave had a negative charge. 2. The POSITRON wave had a positive charge. 3. The NEUTRINO had an electron and positron wave combined and had a neutral charge. 4. The PROTON had a mix of two positrons and one electron combined and had an overall positive charge. 5. The NEUTRON had a mix of two positrons and two electrons combined and had an overall neutral charge. Therefore : Photons made pairs of electrons and positrons. The electrons and positrons mixed together to make neutrinos, protons and neutrons such that: Electron (-) Positron (+) Neutrino (-) (+) Proton (+) (-) (+) Neutron (+) (-) (+) (-) When this production of particles was over, most positrons (anti electrons), didn't exist on their own. They were locked into neutrinos, protons, and neutrons - though conservation of charge was maintained. This may help explain the missing anti matter problem. This period of the Big Bang was probably during the lepton epoch. Though the neutrino and proton are extremely stable. the neutron can be converted back to a proton and electron (with an antineutrino) in beta decay. Protons and electrons can convert to neutrons in neutron stars. So proton + electron = neutrons has already been proven.

[@Cassandra_Johnson]

I have been hunting for a video on just this topic. THANKS! Also a question for a future video: What is alpha radiation always a helium nucleus? I would have thought that ejecting a hydrogen nucleus (a single proton with zero or more neutrons) would take even less energy and thus be more likely, but no one ever suggests this happens, and I can't find anyone explaining why. Keep up the great videos!

[@nafrost2787]

Well I read in wikipedia that sometimes a nucleus can eject a proton, But while I am not a particle physicist I think I have an explantion. The nucleus emits an alpha particle to increase its stability, but it still needs to conserve momentuem, and energy. If it emits 1 proton, that proton gains potential energy (loses eletric but gains strong force), and it must move at high speed to consorve momentuem, but that would mean an increase in kinetic energy, so overall there would be an energy gain if a single proton is ejected. I guess that the best way to conserve both momentuem, and energy, would be the ejection of a helium-4 nucleus (less kinetic energy and less potential strong force energy for the ejected particle). If this sounds a bit foggy and confusing, don't worry I'm just tried and while this is clear in my mind, it takes forever to write, but I can take the time, to write a better explantion of my idea later, if you want.

[@KohuGaly]

en.wikipedia.org/wiki/Alpha_decay#Mechanism TL;DR Alpha particles are smallest, most energetic nuclei, that have net zero spin. Reactions that change spin (especially by non-integer amounts) are less likely than those who don't. Since helium nucleus has such a high energy, it is the most likely to quantum-tunnel out of the nucleus, because the barrier it has to tunnel through is comparatively smaller.

[@Cassandra_Johnson]

@@KohuGaly Thanks, my google is usually strong, but thanks for catching that for me! Ah, quantum tunneling, it does make for such counter intuitive logic.

[@XxPlayMakerxX131]

thank you for simplifying physic and explaining it words I could understnad

[@zakirhussain-js9ku]

Uncertainty principle takes care of mass and energy violations.Please explain if other conserved properties like charge are not violated.

[@eddipl5055]

Thank you Dr. I’ve miss the videos

[@funkyflames7430]

You said neutrinos could emit w bosons. Because we need to conserve charge, does the w boson simply get pass this through uncertainty or does the neutrino produce two w bosons of opposite charge? Or possibly the neutrino emits a positive (or negative) w boson and turns into an electron (or positron). I know the neutrino has to move fairly fast too to be able to provide enough energy.

[@Cassandra_Johnson]

As I understand it, virtual particles don't have to follow conservation laws as long as they cease to exist in a time limit under the Heisenberg uncertainty principle. Also, virtual particles may not even exist, but rather be a math trick to explain the result but not the actual event. Admittedly, if virtual particles are real, even if they do balance the books by disappearing quickly, injecting real energy into an electromagnetic interaction still seems to violate conservation laws on the whole in my mind, because the effect outlasts the uncertainty principle period, so I think this is a great question.

[@drdon5205]

When a neutrino emits a W, It becomes a muon or electron or tau. This was a detail that wasn't mentioned in the video.

[@Simbosan]

Kind of had to read between the lines to get that the size of the z-bosons is affected by the energy of the neutrino. I understood from the video that most neutrinos produced ~100 mass bosons, i.e. the normal preferred mass. The next step took me by surprise

[@timmykenny717]

I got new speakers and immediately was like oh shit I need to hear Don Lincoln on these

[@jasonlough6640]

Questions. Could large mass WBosons be used as a power source? Could subatomic splitting of a nucleus by a neutrino cause a chain reaction of other nucleus being split and so on?

[@cedriceric9730]

can it be used as a power source? not yet

[@cedriceric9730]

can it be used as a power source? not yet

[@knan84]

If you detect the effects of secondary particles created by the boson-proton interaction, how can you ensure that the travel direction of both the neutrinos and the secondary particles are matching?

[@tusharearns]

You are hero dr. Don ❤️❤️ Love from india ❤️

[@nafrost2787]

5:53 Technically the energy is conserved, as far as I understand it, the energy for uncertainty in the energy of the particles, comes from vacuum energy. Either way as revealed by Nother's theorem the energy must be conserved, becuase it doesn't matter when the particles is measured.

[@MrIllusiongamer12]

Aka the disclosure of short periods of time

[@ytashu33]

Great video. So... why Argon? Guessing here... large nucleus (hence greater chances of a neutrino slamming into one), and is liquid at low temps (low temps i suppose are necessary for...). Does it really need to be a noble gas though, or is that part just accidental?

[@drdon5205]

Several reasons. One, heavy nucleus...xenon would be even better. Two, can be made liquid and not at an outrageously low temperature. Three ionizes easily, so argon is both a target and a detector. Four, pretty inexpensive. Five, this technology can result in a finely grained detector, resulting in images like the ones seen in the video.

[@ytashu33]

Makes lotsa sense, yeah inexpensive is important too. Thanks for making what sounded like a mystery (why Argon of all things), into almost an obvious choice, once one understands!! Much Appreciated!!

[@eriknelson2559]

Professor Lisa Randall describes the extent of wave-functions in higher dimension(s) orthogonal to our three large "macro" dimensions, and how the Higgs field resides on one "side" of our membrane at "low" values of the higher dimensional coordinate(s), whereas light particles reside on the opposite "side" of our membrane at "high" values of those coordinates. If so, then neutrino oscillations could be construed as physical oscillations of the neutrino wave functions "in-and-out-and-in-and-out" back and forth through those extra dimension(s). As the neutrinos "porpoise side-to-side" through the fabric of spacetime along the large space & time dimensions, they physically oscillate towards and away from the "Higgs side" of the fabric as they travel. In analogy to a Mechanical Engineering model of the spacetime fabric as an elastic membrane, with one side under compression, the opposite under tension, and a neutral plane of minimal stress & strain down the middle, a heavy neutrino is one which is currently propagating down one "side" or "surface" of the fabric; a light neutrino is one on the opposite "side" or "surface"; and a medium neutrino is one in the middle (say).

[@photon_phi902]

Please could you explain more on sterile neutrinos?

[@johnbennett1465]

From this video it is clear that higher energy neutrenos would be easier to detect. Since you all are smart, you would use them if you could. So this leads to the question of why is it hard to generate higher energy neutrinos?

[@cazymike87]

The most advance Laser its in Romania . It has reached 10% from the power of the Sun in a single spot . Now, to answer your question : You saw that the Sun emits like very small energy neutrino ...and well its an entire Star . We reached just 10% from its power for now . So, do your math, and figurite it by yourself how much power crazy that laser must be . So, where do you get the energy to emit a single high neutrino?? Think about it!

[@johnbennett1465]

@@cazymike87 yes, but the big accelerators can generate particles with much higher energies than the particles in the the center of the sun. The total mass/number of particles is small, but in this case the higher the quality(energy) the less quantiity needed.

[@jagmarz]

So, basically, the neutrino has to emit the weak boson right in the middle of an existing particle, right? If the distance traveled is 1/1000 of the width of a proton, then it basically already has to be right there when it's created. Or am I missing something?

[@drdon5205]

Nope. You got it.

[@DemiImp]

I don't understand what you mean around 7:00 to 7:15. You say that bosons prefer to be around 100 but "the neutrino interactions at Fermilab NEED to be very small". Why do they NEED to be small?

[@drdon5205]

Those interactions don't have enough energy to make heavy ones.

[@DemiImp]

@@drdon5205 Wait what? The lighter the boson, the more energy it has?

[@drdon5205]

@@DemiImp No. Fermi neutrino interactions occur in the few-GeV range. The mass of a W boson is 80 GeV and the mass of the Z boson is 90 GeV. Thus Fermilab neutrino energies are below the mass of the bosons. For solar neutrinos, the neutrinos have energies in the 0.001 GeV range.

[@DemiImp]

@@drdon5205 ... ok, maybe I'm misunderstanding what he means by "neutrino interactions". Is he saying that the neutrinos need to have very little energy? Or is he saying that the neutrinos need to be very close to the neutrons/protons? What is a "small interaction"?

[@Ingy400]

Why do you think bosons are in neutrinos and not the other way around? Also tell us how other things like sound waves and emf waves affect neutrinos. Especially since it is rare to capture the oscillation or is it impervious? Also the location of this detector is also important because uv rays are more common closer to the equator. I hope you thought of this.

[@Ingy400]

Just finished watching you answered one of my questions. But why don't you think neutrinos can't vary in size?

[@MikeRosoftJH]

@@Ingy400 What do you mean, "vary in size"? But yes, neutrinos do "vary in mass". Theory says that there are three neutrino flavors: electron, muon, and tauon neutrinos. There are also three mass states; and these states are not the same as the flavor (or weak force) states. That's what makes neutrino oscillations possible; a neutrino which was originally produced as an electron neutrino may be later detected as a muon neutrino or a tauon neutrino. (As for dimension: neutrinos and other elementary particles are thought to be point particles with no intrinsic size.)

[@tedliu40]

If the speed of neutrino can be slow down, can it interact with other material such as chain reaction by neutrons?

[@joelmcallister9248]

Thank you for posting. Very interesting.

[@MajorMatthias]

Thanks Don. Question at around 7:00 - why do the weak boson interactions detected at Fermilab tend to involve such low-mass bosons? Does this particular neutrino interaction always produce low-mass bosons, or are the low-mass boson interactions the only ones the facility is equipped to detect?

[@drdon5205]

It's because the energy of neutrino beams is a "few" in units where the mass of the weak boson is "100-ish".

[@nafrost2787]

If the neutrino emits a W boson, shouldn't it change from a neutrino into another particle to conserve eletric charge?

[@pritamkumarbishee5053]

Here neutrino emit w boson means neutrino is interact via the weak force carrier ie w boson.

[@nafrost2787]

Yeah but to conserve electric charge, the neutrino needs to change into another particle (the w boson also has electric charge), to which? electron/positron?

[@Quantanaut]

I believe so, it will change into its corresponding charged lepton.

[@KohuGaly]

Yes that is true. It converts into electron muon or some of their anti-matter versions.

[@nafrost2787]

Thanks guys, but what about a tau? or is the tau too heavy?

[@jimkernohan2164]

So how do you know if it is an electron, muon, or tau neutrino?

[@nafrost2787]

6:21 is this function relates somehow to the normal distribution function?

[@drdon5205]

It's called a Breit-Wigner

[@nafrost2787]

Thank you. I wondered what this function is, since I saw the why weak force is weak episode about a month or two ago.

[@omsingharjit]

3:00 this is confusing How weak force w and z can be heavier than protons if it exists in side nucleons as weak force ??

[@radunicoara8057]

It amazes me the idea of having 40 000 Tons of liquid argon.... Where do you even get that amount of Argon? And how do you keep it that cold?

[@ABaumstumpf]

Actually both things are quit simple, the first is just like liquor burning. You just cool down a looooooooot of air till it liquifies and then separate the gasses by boiling them of. And keeping it cold just means isolating it really well and having large chillers to remove the incoming heat (and the heat produced by the sensors). Simple, but needs a lot of money, electricity and infrastructure.

[@drdon5205]

@@ABaumstumpf This is correct. The atmosphere is about 1% argon, so it's not terribly hard.

[@rja7420]

Neutrinos are awesome. I'm really curious to know how fast they are traveling, the percentage of light speed and if that speed is constant for all neutrinos or does the speed vary.

[@qiyuechen7853]

Neutrino's velocity varies from zero to the speed of light.

[@zzztriplezzz5264]

@@qiyuechen7853 Just below the speed of light because they have a mass. Extremely small, but it exists.

[@bennymarshall1320]

So it's a lot easier to detect higher energy neutrinos from events such as gamma ray bursts because they have a greater range of interaction?

[@johngrey5806]

Detecting them is "easy", but how do we even detect something so small? The collision involves breaking apart the nucleus of an atom. How do you build a detector which can send those signals? It's not like you can just hook up a motion sensor from Home Depot or such, we're talking subatomic particles here. And the speed is super short. How do you record the path? I'm just curious.

[@drdon5205]

Fermilab has a few videos on how detectors work.

[@QDWhite]

3:18 how can a neutrino emit a W boson? Wouldn’t conservation of charge prohibit that?

[@QDWhite]

Nevermind, I see he’s answered this in other comments. The neutrino becomes a lepton after emitting the W boson #mischiefmanaged

[@virt1one]

so if these rare light neutrinos travel such a short distance before "going away", how can they make it far enough to hit an atom? It seems like they would have to be created either inside or right at the doorstep of the atom core itself to have any chance at all of hitting anything inside it?

[@ScottJPowers]

so a particle with almost no mass that rarely interacts with matter is making electrons travel faster than the speed of light in water? these detectors are apparently built underground to shield them from radiation, like light or radio, tv, and microwaves because that can cause the same effect. It would seem to me that it is more likely that a bit of radiaition is getting though the shielding. besides, these neutrinos where just made up to explain where energy that could not be accounted for in beta decay went.

[@nickthompson2023]

Scott Powers the particle exists in math, which is proof enough to some scientists. Until we actually detect one, it’s all theoretical to me.

[@MikeRosoftJH]

Gee, good thing that you were the first person to get this idea, that the detector could falsely detect some other kinds of radiation. (Radio or microwave radiation probably won't matter because it has way to little energy; but gamma rays and particles of cosmic radiation are relevant, and that's precisely why the detector is underground.) Seriously, the scientists have to do thorough analysis and calculations to account for false positives; in addition, if the detector is meant to detect neutrinos from a particle accelerator, then you can do a dry run with the neutrino source not active, and estimate from the result just about how often, on average, you could expect to get a false hit.

[@JuliusUnique]

why do the neutrino interactions at Fermilab need to be very small? 7:08 btw

[@3d1stp3rs0n]

With Positron Emission Tomography, the trajectory of beta minus rays can be calculated. Is it possible to use this method for neutrinos and determine where they originated from?

[@stephenzhao5809]

2:15 ... so how do we detect them?

[@connecticutaggie]

Can you explain the comment "in Neutrino scattering using the Fermilab-B, the energies are much much smaller than this hundred-ish number"?

[@prickly_pear88]

So im confused? A nuetrino is one of many detectable/undetectable particles that comes from the sun that is so static in position when traveling towards 🌎 that if, and when a neutrino does make collision with an atom's subatomic particles in an atom-neutrino collision detection field in a lab or elsewhere ; does a neutrino have the chance to create a particle of every atomic sized element on the periodic table?

[@Lucius_Chiaraviglio]

While the mechanism of neutrino detection shown here can work as advertised for high energy neutrinos, it won't work for neutrinos that don't have enough energy to break a nucleus apart, which includes those from the Sun. For those, you have to use one of: Charged current (W+-): Have nuclei that can undergo neutrino capture and electron emission or (antineutrino capture and positron emission) that is just very slightly unfavorable energetically; the emitted electron (or positron) may produce Cerenkov, Askaryan, or scintillation radiation (and an emitted positron will annihilate an electron and produce gamma rays). Old versions of this detection detected the radioactive atoms or even neutrons (from water detector) thus produced. A near future (2022) version will attempt to use induced low energy beta decay.(of tritium) Does not work for muon or tau neutrinos unless they are of sufficiently high energy to pay for the muon or tau particle (which is enough energy to break a nucleus apart, especially in the latter case), and does not work if the neutrino (or antineutrino) energy is insufficient to drive the reverse radioactive decay. Neutral current (Z0): Detect the recoil of an electron struck by a neutrino (or antineutrino), which may produce Cerenkov, Askaryan, or scintillation radiation. Works with all 3 known flavors of neutrinos (and antineutrinos), but does not tell you the flavor. en.wikipedia.org/wiki/Neutrino_detector en.wikipedia.org/wiki/Cowan%E2%80%93Reines_neutrino_experiment en.wikipedia.org/wiki/Cosmic_neutrino_background (scroll to near the end, but worth reading the rest of it)

[@sivarajakrishnamoorthy2601]

Love your videos sir. Can understand very easily. Can u pls make video on the science behind reflection of light??? Pls sir pls....

[@raghulsankar1153]

check out fermat's principle

[@AbdulHaseeb-sm5gy]

I loved the music at beginning ❤️.

[@michaelbennett5417]

Ok. I understand that seeing the interaction is possible. I believe you have understated the difficulty of actually seeing them. I could be understating this but it could be comparable to seeing the transition of Exo planets. Space is big. But the space between atoms is larger.

[@sos_legio_primus]

In the cat example that would lead to very confused and terrified dogs

[@josephbrandenburg4373]

But we would all be a lot nicer to our pet cats!

[@yasminegulistan5446]

Awesome explanation and amazing physics

[@Tubluer]

So. Why are the neutrinos at Fermilab so low in mass? Why don't they favor the 100x a proton mass?

[@photon_phi902]

What the difference types of internation between neutrino and matter? also is true there are 4 difference types of neutrino? And how much is the difference between them a lot of little?

[@jpkotta]

What makes solar neutrinos less likely to interact than Fermilab neutrinos? Are the Fermilab ones more energetic?

[@ABaumstumpf]

Yes. neutrinos formed by Fusion are typically very low mass. Having a low mass but producing a high mass force particle is just very unlikely. As he briefly mentioned - energy conservation (and most other laws) can be broken at sub-Heisenberg scales. The "smaller" the break the likelier it is - basically everything is constantly breaking the energy conservation to a tiny tiny degree for a very short period of time. But neutrinos, to produce the normally way heavier bosons, need to break it big times and that just makes it so unlikely to happen. (it is similar how quantum tunneling gets more and more unlikely the larger the distance).

[@CrisJahnke]

Amanzing!!! Thanks for your channel!

[@petetaylor9758]

Great video as usual, but I have one question: is there a specific "signature" in the signals detected to identify the initial cause as a neutrino? I believe there are other experiments trying to detect things like dark matter, proton decay etc. Since dark matter (like neutrinos) can't be detected directly but only by knock-on effects (via the weak force?), is there theoretically a difference between the expected signals?

[@joseluisblanco8074]

D.Lincoln, following this video are all fundamental particles tabulated masses only a mean value in a probability distribution? Can´t it be the other way down, and have a number of neutrinos with an extraordinary high mass that interact easily with matter?

[@drdon5205]

Yes and yes.

[@paulmicks7097]

I missed or can't see how or when neutrinos are created , during fusion of atoms ?

[@JugheadJones03]

How can they tell its a Neutrino collision and not another type of sub atomic particle reaction in Dune? Is it because they look for certain electrical output amount, and can rule it out that way?

[@gabeg.2848]

I don't understand though how does a neutrino emits a weak interaction. Should there be conservation of mass and charge to it? How can neutraly charged neutrino emit a w boson? And the mass of a neutrino is very low (but I believe the energy contained within is translated into the mass of the mass?)

[@davelowinger7056]

Why did they use argon gas instead of frozen hydrogen? If I was to guess it was because it has a bigger proton in the electron field is probably easily shared at a warmer temperature?

[@asdfdfggfd]

Are neutrinos the cause of spontaneous radioactive decay? Or are there particle interactions other than neutrinos that release W and Z bosons?

[@MikeRosoftJH]

It's the other way around. A neutron spontaneously decays into a proton and an electron; and because all known interactions (except neutrino oscillation) preserve the individual lepton numbers, it will also release an electron antineutrino. And because neutron decays by weak force, so when you look at the Feynman diagram of the reaction, it will involve a W boson. The same happens during beta decay of atomic nuclei - a neutron converts into a proton, or vice versa, and releases either an electron or a positron (to preserve electric charge) and an electron antineutrino or neutrino (to preserve an electron number). The decay can only occur if the system after the decay has less energy than before the decay (the remaining energy going to the energy of the escaping particles); and the probability that it happens in a unit of time depends on the difference of energy. (For example, the difference between mass-energy of a neutron, and a proton-electron pair, is minuscule; that's why the decay of a free neutron takes many minutes - this is ages from the point of view of nuclear physics.)

[@photon_phi902]

Is neutrino can do 2 difference thing or function? And is it possible to categories neutrino in 2 difference category with different function or beginning of behavior?

[@ADITYAKUMAR-mb5ht]

Thanks for making such kind of awesome video siry

[@vladnurk4710]

Have a question that have been bothering me. If the 1/2 life of a neutron is 14 hrs & 39 sec why haven't all neutrons in atoms & neutron stars decayed into a proton + electron & a neutrino?

[@jahtea7849]

I'm a little dense, how does the weak boson smash or pass through a nucleus if it only exists long enough to travel the distance of the size of a proton? I have misunderstood something fundamental, i think.

[@ahamdzaarour7853]

how did we know the spin of differnt particles such as bosons fermions ? for example why fermions has spin =1/2 integer and why bosons has an integer spin?

[@timmykenny717]

So if a particle emitted from the Sun makes it to the Earth at the speed of light and experiences zero time does that mean that it experiences zero space being passed? If so then space is compactified for any particle moving at C making it one dimensional from their reference frame right? And if that is true wouldn't that imply that a particle moving at 0 Kelvin or 0 times C would experience no dimensions? (i dont know but i feel how wrong that explanation technically is..) I guess my question is where would you draw a two-dimensional reference frame from this analogy Or does the real impact of numbers actually lose meaning after three dimensional space making our three-dimensional point of view of a two-dimensional reference frame obsolete? I even wonder if this makes us misunderstand that we are drawing a two dimensional line in quantum when we talk about a particle Landing in any one position. We can think of a straight defined path from our three-dimensional point of view of this particle but maybe the particle doesn't have a straight line from our reference frame. if that were true then I would assume that it means that that extra second dimension must be time? if you add it in anywhere else then any particle would have to take extra time violating causality ("second" dimension=time no pun intended.....)