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Astronomers Detected a 'Ghost Particle' and Tracked It To Its Source (space.com)

Posted by BeauHD on from the first-of-its-kind dept.

An anonymous reader quotes a report from Space.com: Astronomers have traced a high-energy neutrino to its cosmic source for the first time ever, solving a century-old mystery in the process. Observations by the IceCube Neutrino Observatory at the South Pole and a host of other instruments allowed researchers to track one cosmic neutrino to a distant blazar, a huge elliptical galaxy with a fast-spinning supermassive black hole at its heart. And there's more. Cosmic neutrinos go hand in hand with cosmic rays, highly energetic charged particles that slam into our planet continuously. So, the new find pegs blazars as accelerators of at least some of the fastest-moving cosmic rays as well. Astronomers have wondered about this since cosmic rays were first discovered, way back in 1912. But they've been thwarted by the particles' charged nature, which dictates that cosmic rays get tugged this way and that by various objects as they zoom through space. Success finally came from using the straight-line journey of a fellow-traveler ghost particle.

On Sept. 22, 2017, [...] IceCube picked up another cosmic neutrino. It was extremely energetic, packing about 300 teraelectron volts -- nearly 50 times greater than the energy of the protons cycling through Earth's most powerful particle accelerator, the Large Hadron Collider. Within 1 minute of the detection, the facility sent out an automatic notification, alerting other astronomers to the find and relaying coordinates to the patch of sky that seemed to house the particle's source. The community responded: Nearly 20 telescopes on the ground and in space scoured that patch across the electromagnetic spectrum, from low-energy radio waves to high-energy gamma-rays. The combined observations traced the neutrino's origin to an already-known blazar called TXS 0506+056, which lies about 4 billion light-years from Earth. The IceCube team also went through its archival data and found more than a dozen other cosmic neutrinos that seemed to be coming from the same blazar. These additional particles were picked up by the detectors from late 2014 through early 2015. The findings are reported in two separate studies published in the journal Science.

47 comments

  1. About Time by Aighearach · · Score: 4, Funny

    I'm just glad IceCube is doing something useful with the rest of his life.

    1. Re:About Time by BeauHD+(5) · · Score: -1

      Don't forget the Russians. Vladimir Putin himself was "tracked" to the "source of TRUMP" medaling.

    2. Re: About Time by akical0118 · · Score: 1

      Wow beau how far you've fallen

    3. Re:About Time by Anonymous Coward · · Score: 1

      IceCube knows which joint blazars at
      IceCube 'scopes to point interphasers at
      Neutrino made no force, still snapped 'em
      IceCube nails the source, distilled fat datum

      word

    4. Re: About Time by Anonymous Coward · · Score: 0

      Anti-Russian haters with their crazy conspiracy theories. There was no meddling.

      The Certainty Principle says particles will be distributed through space in a Bell curve and that creates the illusion of a wave. No time required. Stick that in your quantum pipe and smoke it!

    5. Re:About Time by radarskiy · · Score: 1

      Fuck tha positron! Detectin straight from the underground

    6. Re:About Time by Anonymous Coward · · Score: 0

      Well done!

    7. Re:About Time by Anonymous Coward · · Score: 0

      really, this is legit readable as rap or as telescopy, and it has a +1 mod not a +3 "lol physics puns"?

  2. How did they find the source? by AlanObject · · Score: 1

    I am wondering how they managed to find the source.

    Does the detector give them a vector of direction? After that how many calculations are needed? I would think you would have to figure in Earth's rotation, Earth's orbit, the sun's orbit, and the galaxy's path. Presumably the neutrino was traveling somewhat below C so there must be an adjustment there. All that to get a direction to look. Am I off base on this or is it not that complex?

    All I can say is Astronomers must have fiendish concentration skills for math.

    1. Re:How did they find the source? by jfdavis668 · · Score: 4, Informative

      There was a link to it in the story: https://www.space.com/41147-co...

    2. Re:How did they find the source? by Anonymous Coward · · Score: 0

      It does seem very hand-wavy. I bet the phrase "margin of error" features prominently during an explanation.

    3. Re:How did they find the source? by careysub · · Score: 3, Insightful

      Yes, they can track the neutrino through the detector, and that gives them a direction. In this case the single detection had a 90% error box of 1.6 degrees x 0.8 degrees. Gamma ray instruments looking in this direction detected increased activity of the blazar, with a combined significance of 3 sigmas. Adding the previous neutrino detections from this apparent source allows even more accurate source determination.

      --
      Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
    4. Re:How did they find the source? by Michael+Woodhams · · Score: 3, Informative

      I've just quickly looked at the Science article. Here is the plot you want. (I hope that doesn't need institutional access to view.)

      The 90% confidence contour for arrival direction of the neutrino is roughly elliptical with length/width (major/minor axis) about 1.5 degrees and 1 degree - so you are right, the direction of the neutrino has quite large uncertainty.

      The high energy gamma rays detected by the MAGIC telescopes (in response to the neutrino triggered alert) have 95% confidence ellipse about 0.1 degree diameter. A previously identified gamma ray source has 95% confidence ellipse about 0.03 degrees in diameter. All are consistent with the location of TXS 0506+056.

      --
      Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
    5. Re:How did they find the source? by Michael+Woodhams · · Score: 4, Informative

      The hard bit is 'given the timings and intensities of flashes I detected in my detector, what was the direction of the primary neutrino?' That gives a direction relative to the detector array, then all you need to know is the sidereal time and location on Earth of the detector to turn it into a direction on the sky, with some simple addition of angles. The uncertainty in neutrino direction is on the order of a degree (I've commented elsewhere on this) so effects much smaller than a degree can be ignored.

      I did calculations quite similar to this for a cosmic ray experiment in my MSc thesis in 1988/89. I used likelihood calculations to determine direction and uncertainty in direction. I expect this experiment does the same.

      --
      Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
    6. Re:How did they find the source? by datavirtue · · Score: -1, Troll

      They are full of shit. I wish people would stop with the "black hole" shit and just call it a "massive gravity anomoly" instead. Black holes are theoretical and using the term serves only to confuse the plebs who now think they are a real thing--a fact. Fake news.

      --
      I object to power without constructive purpose. --Spock
    7. Re:How did they find the source? by datavirtue · · Score: 1

      "90% error box of 1.6 degrees x 0.8 degree"

      Which translates to "maybe it was this galaxy...or no it was that one....oh, which one was it again?"

      --
      I object to power without constructive purpose. --Spock
    8. Re:How did they find the source? by Anonymous Coward · · Score: 0

      I always knew Blaze was a dick.

    9. Re: How did they find the source? by Anonymous Coward · · Score: 0

      But how can they observe a direction unless the same neutrino interacts with more than one detector? Is that the chance encounter they are waiting for?
      And once the neutrino interacts with the first detector, isn't it changed (I would think destroyed)?

    10. Re: How did they find the source? by Anonymous Coward · · Score: 0

      Did you just spell anomaly wrong?

    11. Re:How did they find the source? by Michael+Woodhams · · Score: 5, Informative

      But when they issued the alert, other telescopes started looking at that 1.6 by 0.8 degrees. Some telescopes detected high energy gamma rays in the area, and those telescopes had much better accuracy. And there was a previously detected gamma ray source, located with even higher spacial accuracy, within that error ellipse. And the galaxy in turn was within this smallest error ellipse.

      Here is the picture.

      Even the smallest error ellipse probably contains a bunch of galaxies. I presume that just one of them looked 'weird' in some way, and so was assumed to have interesting activity at its core. I haven't taken the time to drill down that far into their identification process.

      --
      Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
    12. Re:How did they find the source? by idji · · Score: 1

      Do these events shed any light on the speed and mass of neutrinos?

    13. Re:How did they find the source? by Roger+W+Moore · · Score: 1

      No, to do that you would need to tie neutrino emission to some visible change detectable by light in a source and then measure the difference in time of arrival between the light and the neutrino. This is because particles with a mass always have a velocity less than light and if your propagation distance is long enough this will result in light arriving before the neutrino.

      However, incredibly high energy neutrinos like this are not the ones you want to use because, even with a really distant source, their energy is so great and their mass so small that even with incredibly long baselines the difference in arrival time with light will be incredibly small. This neutrino had about 40 times the energy of an LHC proton but a mass that is at least about a billion times smaller and probably closer to a trillion times smaller - we do not actually know because the mass is so small nobody has ever managed to measure it!

    14. Re:How did they find the source? by Thelasko · · Score: 1

      Your comment is very helpful. When I first read the article I thought, "they sent an automatic message to astronomers around the world in less than a minute. Why did it take them so long?" However, after reading your comment, now I realize they probably used the likelihood calculations you mention to automatically tell the astronomers where in the sky to look.

      However, since you were performing these calculations in 1989, I'm still kinda wondering why it took them so long to do this. Are these calculations difficult to automate?

      --
      One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
    15. Re: How did they find the source? by Agripa · · Score: 1

      But how can they observe a direction unless the same neutrino interacts with more than one detector? Is that the chance encounter they are waiting for?
      And once the neutrino interacts with the first detector, isn't it changed (I would think destroyed)?

      The neutrinos do not interact with the detectors. Instead they react with the hydrogen in the water to produce charged leptons (electrons, muons, or taus depending on the neutrino type) which then produce Cherenkov radiation as they move through the ice and the detectors see that. Since momentum is conserved, the leptons move in approximately the same direction as the neutrino was.

      https://pippagoldenberg.wordpr...

      Neutrinos are electrically neutral leptons, and interact very rarely with matter. When they do react with the molecules of water in the ice, they can create charged leptons (electrons, muons, or taus). These charged leptons can, if they are energetic enough, emit Cherenkov radiation. This happens when the charged particle travels through the ice faster than the speed of light in the ice, similar to the bow shock of a boat traveling faster than the waves it crosses. This light can then be detected by photomultiplier tubes within the digital optical modules making up IceCube.

      https://en.wikipedia.org/wiki/...

  3. Seek & DESTROY - Metallica by Anonymous Coward · · Score: -1

    Khazar Talmudic Jews believe this of all they call goyim/gentiles (any non-jew): Jews = biggest racists of all (for which they "jew guilt" you for no less! They're hypocrites known as thieves all thru history or were Argentines in the 1940 under Peron, Spanish inquistion, France (1306), Egypt (despoiled/robbed by jews), Arabs (pre & post 1948), England (1330 Edward longshanks), Romans under titus, Russia pogroms and Germany who got rid of them from their nations nazi german's too? No. Driven into DESERTS ages ago! Don't wonder why after all those exilings above.

    Should anyone doubt any of this see Jacob Javits' crony Rosenthal spill the beans on it https://www.youtube.com/watch?v=D4zMVZ8HnFI/ where he called all Christianity fools for helping Israel and the biggest scam of all time per their beliefs below from their Talmud.

    This is the province of the synagogue of Satan (Pharisees whom Jesus Christ himself kicked to the curb out of the temple & they killed him for it. Jeremiah did the same to them also + the Essenes could not stand them either breaking away from the pharisee corruption):

    Mark Zuckerberg stole the Winklevoss twins' code for Fakebook (figures as he is a thieving low jew too).

    Maria Abramovic satanist spirit cooker pal of Hillary Clinton the Voodoo queen is a jew https://www.google.com/search?...

    Like Hillary Clinton's mentor Saul Alinsky author of rules for radicals book dedicated to Lucifer

    "Most Jews do not like to admit it, but our god is Lucifer Â- so I wasnÂ't lying Â- and we are his chosen people. Lucifer is very much aliveÂ" Harold Rosenthal http://www.thetruthseeker.co.u...

    Jewish rabbi openly admits to satan worship use white children's blood they kill for passover bread, infiltrating and subverting the catholic church, creating the Jesuit order https://www.youtube.com/watch?... and https://www.youtube.com/watch?...

    Barbara Spectre, a jew, tells everyone it's jews orchestrating the muslim migrant problem in Europe https://www.youtube.com/watch?v=MFE0qAiofMQ/ . No migrant raping of women in Poland. Tons in Sweden. Do the math. Use common-sense. This is to get muslims and other goyim/gentiles to wipe one another out as incompatible cultures that will clash and always have.

    Rabbi A. Finkelstein ADMITS their greatest enemies are ARABS and WHITES (blacks too) whom they wish to kill one another in a 'theater of war' which they find AMUSING https://www.youtube.com/watch?...

    Finkelstein also admits JEWS DID 9/11 (perpetrated by the Mossad & Bebe Netanyahu of ISRAEL) https://www.youtube.com/watch?... profiting by it (and that 3,000 jews employed there did not show up for work that day knowing about it beforehand).

    Finkelstein also admits JEWS are going to destroy the U.S. Dollar and dumping it for other world currencies and gold to destroy the United States.

    George Soros who funds groups to create division in the USA?? A jew. One who sold his own jew people into death for the nazis.

    Zucker now FIRED @ CNN is another frying publicly for lying about "russians" and John Bonifield a producer @ CNN said it is bs. Van Jones did also.

    Bernie Madoff (who made off with everyone's money, especially construction union pensions) shows the thieving nature of the JUDEN!

    Eric Schmidt had to step down @ JEWgle (a jew).

    Adam Schiff (gosh s

  4. That ain't BeauHD by Anonymous Coward · · Score: 0

    That isn't Beau. That is beau number 5. Pay attention better as there are several beauhd accounts with different numbers after the name. A quick scan of the name makes you think that guy has a UID of 5 when it's actually 5406192 upon closer inspection.

    1. Re:That ain't BeauHD by Anonymous Coward · · Score: 0

      Well, BeauHD had grown so rich, he wanted to retire. He took me to his cabin and he told me his secret. 'I am not the BeauHD (5)', he said. 'My name is Ryan; I inherited the ship from the previous BeauHD, just as you will inherit it from me. The man I inherited it from is not the real BeauHD either. His name was Cummerbund. The real BeauHD has been retired fifteen years and living like a king in Patagonia.'

  5. Re:About Time TrumpO for 2020-2024!!! by Anonymous Coward · · Score: 0

    And also Don't forget Trump for 2020-2024!!! Trump has already won !!!!

  6. Big ups by Purevoice · · Score: 0

    what a great discovery, big ups to the astronauts https://toponlineviews.tumblr....

    --
    I love to blog http://www.naijadailyfeed.com
    1. Re:Big ups by Anonymous Coward · · Score: 0

      Spam?

    2. Re:Big ups by Anonymous Coward · · Score: 0

      Yup. Spam.

  7. Re:About Time TrumpO for 2020-2024!!! by datavirtue · · Score: 1

    Bigly

    --
    I object to power without constructive purpose. --Spock
  8. this guys writing annoys me by Anonymous Coward · · Score: 0

    It's interesting subject matter, but the author is just completely and totally painful to read. I can't put my finger on what it is exactly though...

  9. "MASTER OF PUPPETS..." by Anonymous Coward · · Score: -1

    Khazar Talmudic Jews believe this of all they call goyim/gentiles (any non-jew): Jews = biggest racists of all (for which they "jew guilt" you for no less! They're hypocrites known as thieves all thru history or were Argentines in the 1940 under Peron, Spanish inquistion, France (1306), Egypt (despoiled/robbed by jews), Arabs (pre & post 1948), England (1330 Edward longshanks), Romans under titus, Russia pogroms and Germany who got rid of them from their nations nazi german's too? No. Driven into DESERTS ages ago! Don't wonder why after all those exilings above.

    Should anyone doubt any of this see Jacob Javits' crony Rosenthal spill the beans on it https://www.youtube.com/watch?v=D4zMVZ8HnFI/ where he called all Christianity fools for helping Israel and the biggest scam of all time per their beliefs below from their Talmud.

    This is the province of the synagogue of Satan (Pharisees whom Jesus Christ himself kicked to the curb out of the temple & they killed him for it. Jeremiah did the same to them also + the Essenes could not stand them either breaking away from the pharisee corruption):

    Mark Zuckerberg stole the Winklevoss twins' code for Fakebook (figures as he is a thieving low jew too).

    Maria Abramovic satanist spirit cooker pal of Hillary Clinton the Voodoo queen is a jew https://www.google.com/search?...

    Like Hillary Clinton's mentor Saul Alinsky author of rules for radicals book dedicated to Lucifer

    "Most Jews do not like to admit it, but our god is Lucifer Â- so I wasnÂ't lying Â- and we are his chosen people. Lucifer is very much aliveÂ" Harold Rosenthal http://www.thetruthseeker.co.u...

    Jewish rabbi openly admits to satan worship use white children's blood they kill for passover bread, infiltrating and subverting the catholic church, creating the Jesuit order https://www.youtube.com/watch?... and https://www.youtube.com/watch?...

    Barbara Spectre, a jew, tells everyone it's jews orchestrating the muslim migrant problem in Europe https://www.youtube.com/watch?v=MFE0qAiofMQ/ . No migrant raping of women in Poland. Tons in Sweden. Do the math. Use common-sense. This is to get muslims and other goyim/gentiles to wipe one another out as incompatible cultures that will clash and always have.

    Rabbi A. Finkelstein ADMITS their greatest enemies are ARABS and WHITES (blacks too) whom they wish to kill one another in a 'theater of war' which they find AMUSING https://www.youtube.com/watch?...

    Finkelstein also admits JEWS DID 9/11 (perpetrated by the Mossad & Bebe Netanyahu of ISRAEL) https://www.youtube.com/watch?... profiting by it (and that 3,000 jews employed there did not show up for work that day knowing about it beforehand).

    Finkelstein also admits JEWS are going to destroy the U.S. Dollar and dumping it for other world currencies and gold to destroy the United States.

    George Soros who funds groups to create division in the USA?? A jew. One who sold his own jew people into death for the nazis.

    Zucker now FIRED @ CNN is another frying publicly for lying about "russians" and John Bonifield a producer @ CNN said it is bs. Van Jones did also.

    Bernie Madoff (who made off with everyone's money, especially construction union pensions) shows the thieving nature of the JUDEN!

    Eric Schmidt had to step down @ JEWgle (a jew).

    Adam Schiff (gosh s

  10. Convert to Joules by Anonymous Coward · · Score: 0

    So 300TeV is 50 microjoules. The energy required to lift 1g by 1mm on Earth, if my maths is right. And this comes from a single neutrino. Mind blown...

    1. Re:Convert to Joules by Anonymous Coward · · Score: 0

      Of course my maths is wrong. Maybe 1g by 5mm? Anyone care to check it?

  11. "Master of Puppets pulling the strings..." by Anonymous Coward · · Score: -1

    Khazar Talmudic Jews believe this of all they call goyim/gentiles (any non-jew): Jews = biggest racists of all (for which they "jew guilt" you for no less! They're hypocrites known as thieves all thru history or were Argentines in the 1940 under Peron, Spanish inquistion, France (1306), Egypt (despoiled/robbed by jews), Arabs (pre & post 1948), England (1330 Edward longshanks), Romans under titus, Russia pogroms and Germany who got rid of them from their nations nazi german's too? No. Driven into DESERTS ages ago! Don't wonder why after all those exilings above.

    Should anyone doubt any of this see Jacob Javits' crony Rosenthal spill the beans on it https://www.youtube.com/watch?v=D4zMVZ8HnFI/ where he called all Christianity fools for helping Israel and the biggest scam of all time per their beliefs below from their Talmud.

    This is the province of the synagogue of Satan (Pharisees whom Jesus Christ himself kicked to the curb out of the temple & they killed him for it. Jeremiah did the same to them also + the Essenes could not stand them either breaking away from the pharisee corruption):

    Mark Zuckerberg stole the Winklevoss twins' code for Fakebook (figures as he is a thieving low jew too).

    Maria Abramovic satanist spirit cooker pal of Hillary Clinton the Voodoo queen is a jew https://www.google.com/search?...

    Like Hillary Clinton's mentor Saul Alinsky author of rules for radicals book dedicated to Lucifer

    "Most Jews do not like to admit it, but our god is Lucifer Â- so I wasnÂ't lying Â- and we are his chosen people. Lucifer is very much aliveÂ" Harold Rosenthal http://www.thetruthseeker.co.u...

    Jewish rabbi openly admits to satan worship use white children's blood they kill for passover bread, infiltrating and subverting the catholic church, creating the Jesuit order https://www.youtube.com/watch?... and https://www.youtube.com/watch?...

    Barbara Spectre, a jew, tells everyone it's jews orchestrating the muslim migrant problem in Europe https://www.youtube.com/watch?v=MFE0qAiofMQ/ . No migrant raping of women in Poland. Tons in Sweden. Do the math. Use common-sense. This is to get muslims and other goyim/gentiles to wipe one another out as incompatible cultures that will clash and always have.

    Rabbi A. Finkelstein ADMITS their greatest enemies are ARABS and WHITES (blacks too) whom they wish to kill one another in a 'theater of war' which they find AMUSING https://www.youtube.com/watch?...

    Finkelstein also admits JEWS DID 9/11 (perpetrated by the Mossad & Bebe Netanyahu of ISRAEL) https://www.youtube.com/watch?... profiting by it (and that 3,000 jews employed there did not show up for work that day knowing about it beforehand).

    Finkelstein also admits JEWS are going to destroy the U.S. Dollar and dumping it for other world currencies and gold to destroy the United States.

    George Soros who funds groups to create division in the USA?? A jew. One who sold his own jew people into death for the nazis.

    Zucker now FIRED @ CNN is another frying publicly for lying about "russians" and John Bonifield a producer @ CNN said it is bs. Van Jones did also.

    Bernie Madoff (who made off with everyone's money, especially construction union pensions) shows the thieving nature of the JUDEN!

    Eric Schmidt had to step down @ JEWgle (a jew).

    Adam Schiff (gosh s

    1. Re: "Master of Puppets pulling the strings..." by Anonymous Coward · · Score: 0

      You forgot baseball

  12. Sorry if this is a dumb question, but... by Assmasher · · Score: 1

    How could they possible track where the neutrino came from given their incredibly sporadic observability for measurement, a spinning earth, a spinning solar system, a spinning arm of the milky way - and 4 billion light years distance?

    The article says they notified astronomers of a patch of sky that was a candidate for the source - how could this be correct if our galaxy is spinning?

    Again, apologies if this is a dumb question, but thank to Einstein I think everything's relative - especially the orientation of bodies ;).

    --
    Loading...
    1. Re:Sorry if this is a dumb question, but... by Anonymous Coward · · Score: 0

      If the neutrino is traveling at close to the speed of light (which I think it is) then you don't have to worry about that - you consider the apparent direction that the neutrino came from at the moment of detection. You'll be getting photons from the source in exactly the same apparent place and time.

    2. Re:Sorry if this is a dumb question, but... by avandesande · · Score: 1

      Interestingly enough although neutrinos don't go faster than light in a vacuum they don't interact with matter so the neutrinos would arrive a small amount of time before the photons which are slowed by the traces of gas in interstellar space.

      --
      love is just extroverted narcissism
    3. Re:Sorry if this is a dumb question, but... by iggymanz · · Score: 1

      how fast does the earth spin for an object going essentially lightspeed? Not at all, essentially. A distant galaxy subtends an incredibly minute portion of the sky, irrelevant its spin, all components of a photon or neutrinos velocity will sum up to lightspeed in one direction.

    4. Re:Sorry if this is a dumb question, but... by Assmasher · · Score: 1

      You seem to be forgetting that the neutrino has been traveling to us for, apparently, 4 billion years. The speed at which galaxies move over 4 billion years is significant - not to mention the rotation of our galaxy relative to the orientation of the speculated galaxy is huge.

      --
      Loading...
    5. Re:Sorry if this is a dumb question, but... by Assmasher · · Score: 1

      BTW, it takes a little over 200 million years to completely rotate around the center of our galaxy (i.e. a 'cosmic year')

      --
      Loading...
  13. Track Pointing by Roger+W+Moore · · Score: 3, Informative

    I am wondering how they managed to find the source.

    When this neutrino interacted with the ice it converted itself into a muon which is a heavy cousin of the electron that can travel a huge distance through the ice at these energies. So what we saw was a track of light that moved through the whole ~1km width of the detector that we could then point back to a region of the sky. So we do not detect the neutrino itself only what it produces after an interaction and, if it produces a muon, we have a good long track if there is enough energy.

    The light from the track is because the muon has a charge and travels incredibly close to the speed of light in vacuum. However, the speed of light in ice is quite a bit less than the speed in vacuum and so the muon emits a shockwave cone of light called Cherenkov radiation just like a supersonic aircraft emits a conical sonic shockwave of sound called the sonic boom.

  14. See daughter particles, not neutrinos by Roger+W+Moore · · Score: 3, Interesting

    Yes, they can track the neutrino through the detector, and that gives them a direction.

    Not quite - we cannot see neutrinos directly. What we see are the particles they produce when they interact in the ice. At these energies, the boost of the particles created is so large that it basically has the same direction as the original neutrino. However, if the neutrino produces an electron or a tau (unless it is really high energy) this produces a cascade of particles which we see as a point source that has little to no pointing. Only when the neutrino produces a muon do we get a long track that we can point back to the source.

  15. Re:About Time TrumpO for 2020-2024!!! by Anonymous Coward · · Score: 0

    And also Don't forget Trump for 2020-2024!!!

    Only till 2024? Are you kidding? Putin has already managed 18 years on an 8-year position.