Hi! Questions? CORRECTION: My "fun fact" (around the 9-minute mark) about the top-antitop production processes at the Tevatron vs the LHC being different was not quite right. I said that the reason the main production process was different at LHC and the Tevatron was because the LHC collided protons with protons, and the Tevatron collided protons with antiprotons. If the LHC had been run at the same energy as the Tevatron was, what I said would have been correct. However, the importance of these processes also changes with energy. The main reason that the predominant production process differs between LHC and the Tevatron is actually due to the energy of the LHC being much higher, and not the difference between proton-proton and proton-antiproton collisions. Sorry for the error!
37(n+n+n)=nnn for 0 < n < 10. Sin (666) + Cos (6*6*6) = -1.618... (golden ratio). Belphegor's prime is the palindromic prime number 1000000000000066600000000000001 (10^30 + 666 × 10^14 + 1).
@@physdb it could have produced it per see, but not enough events for them to be statistically significant. lumi was low for that. it did however put a mass limit on higgs (110-140 some GeV), but lhc announced higgs soon after that.
Hi! I can give you a partial answer. A more complete answer would take me some time, I'm afraid. The short answer is that the Tevatron was able to get what was probably a glimpse of the Higgs, but not enough of one to declare a discovery. In the region of the Higgs mass (125 GeV), the Tevatron did, in fact, see an excess of something like 2.5-3 sigma. So, they presumably did see Higgs bosons in their detectors, but not enough of them. The main processes by which the Higgs is produced at either collider become more common as you move to higher energies. So, if you increase the energy, more Higgses are produced. So, the main answer is that, because the LHC ran at a higher energy, more Higgses were produced, and so LHC was able to make enough of them for a discovery, and the Tevatron wasn't. (The integrated luminosities of the two machines at the time of the Higgs discovery were not that different. Now, however, the LHC has far outstripped the Tevatron.) That's the big picture, but there are also probably some interesting details. The Higgs can be produced by different mechanisms, and it can decay to different sets of particles. Each one of these different mechanisms requires a different experimental analysis. The primary analysis used at LHC to make the discovery looked at the Higgs decaying to 2 photons; this is a rare decay, but it is experimentally very clean. Unfortunately, because it's a rare decay, the Tevatron simply didn't have enough of them for this to be a feasible way to discover the Higgs. They did look at the decay of the Higgs boson to a bottom quark-antiquark pair, which is a very common decay, but much more difficult. (The LHC experiments did report seeing this decay, but years later.) So, because the LHC and the Tevatron had to take different analysis strategies, there is probably a bit more to the story than what I'm describing here, but it should be the rough idea. Thanks!
Another exceptionally clear video-- this channel is massively under-subscribed
Hi! Questions?
CORRECTION: My "fun fact" (around the 9-minute mark) about the top-antitop production processes at the Tevatron vs the LHC being different was not quite right. I said that the reason the main production process was different at LHC and the Tevatron was because the LHC collided protons with protons, and the Tevatron collided protons with antiprotons. If the LHC had been run at the same energy as the Tevatron was, what I said would have been correct. However, the importance of these processes also changes with energy. The main reason that the predominant production process differs between LHC and the Tevatron is actually due to the energy of the LHC being much higher, and not the difference between proton-proton and proton-antiproton collisions. Sorry for the error!
Excellent. Thank you.
Thank You!!
Great explanation
37(n+n+n)=nnn for 0 < n < 10. Sin (666) + Cos (6*6*6) = -1.618... (golden ratio). Belphegor's prime is the palindromic prime number 1000000000000066600000000000001 (10^30 + 666 × 10^14 + 1).
Crackpots be like
With energy 1 TeV Tevatron could find Top quark. But why Tevatron couldn't find the Higgs boson at that time?
higgs processes are much rarer. you need a lot of data collected over a long time.
Luminosity of Tevatron is not big enough to produce Higgs?
@@physdb it could have produced it per see, but not enough events for them to be statistically significant. lumi was low for that. it did however put a mass limit on higgs (110-140 some GeV), but lhc announced higgs soon after that.
Hi!
I can give you a partial answer. A more complete answer would take me some time, I'm afraid.
The short answer is that the Tevatron was able to get what was probably a glimpse of the Higgs, but not enough of one to declare a discovery. In the region of the Higgs mass (125 GeV), the Tevatron did, in fact, see an excess of something like 2.5-3 sigma. So, they presumably did see Higgs bosons in their detectors, but not enough of them.
The main processes by which the Higgs is produced at either collider become more common as you move to higher energies. So, if you increase the energy, more Higgses are produced. So, the main answer is that, because the LHC ran at a higher energy, more Higgses were produced, and so LHC was able to make enough of them for a discovery, and the Tevatron wasn't. (The integrated luminosities of the two machines at the time of the Higgs discovery were not that different. Now, however, the LHC has far outstripped the Tevatron.)
That's the big picture, but there are also probably some interesting details. The Higgs can be produced by different mechanisms, and it can decay to different sets of particles. Each one of these different mechanisms requires a different experimental analysis. The primary analysis used at LHC to make the discovery looked at the Higgs decaying to 2 photons; this is a rare decay, but it is experimentally very clean. Unfortunately, because it's a rare decay, the Tevatron simply didn't have enough of them for this to be a feasible way to discover the Higgs. They did look at the decay of the Higgs boson to a bottom quark-antiquark pair, which is a very common decay, but much more difficult. (The LHC experiments did report seeing this decay, but years later.) So, because the LHC and the Tevatron had to take different analysis strategies, there is probably a bit more to the story than what I'm describing here, but it should be the rough idea.
Thanks!
@@ThinkLikeaPhysicist Thanks. By the way do you have this video talking about these two experiments searching for the Higgs boson?
heh, there are now resonances detected beyond Higgs energies...