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2d
comment How can an electron fake a jet?
Experimenters are pragmatists. We do our level best to figure out the processing scheme that will get the most out of the data and then we use that scheme. Sometimes you can work that out on the back of an envelope; sometime is takes a twenty-page white-paper; and sometime you just have to Monte Carlo it to a fare-thee-well.
2d
awarded  Nice Answer
2d
comment How can an electron fake a jet?
At this point I run into the fact that I've never done collider physics. I don't know enough to be certain why they would chose a particular approach. You could get coincident signals in the calorimeters several ways. Incident electron + DIS. Incident hadron and a single hard electron scattering event (should be rare but is certainly possible). Coincidental arrival from two sources. Weak decay of a flavored hadron at the right time. Probably others. Whatever scheme you chose has to fail well across all the options.
2d
answered How can an electron fake a jet?
Apr
25
revised A reference request for real world experimental data
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Apr
24
comment How does Compton scattering demonstrate particle over wave behavior?
"some people consider it to be a waste of time apparently" It's not so much a waste of time, but that the time simply isn't available if students are to be shepherded through the usual preparation in the usual number of terms at conventional loads. I consider it an advantage of ahistorical ordering in a modern physics course that you can pick and chose which transition arguments to present. Those that won't be covered in adequate detail simply aren't covered at all. Of course that replaces a superficial historical awareness with a deeper but patchy one, so you could reasonably disagree.
Apr
24
revised Measuring very long half lives accurately
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Apr
24
comment Conventions for propagators in Feynman diagrams
Chat discussion: chat.stackexchange.com/transcript/message/29225208#29225208
Apr
24
comment Conventions for propagators in Feynman diagrams
To duplicate my wording on a chat discussion of this questions: There is no Ruling Junta of Physics Notations and Conventions and this stuff varies. And that's a general rule. Conventions develop, settle, get shaken up, mutate, re-settle, exist in two armed camps for decades at a time, and exhibit all kinds of behavior and divergences. It's simply not safe to think that there is One True Way to do things. And even when there is One True Way right now there is no guarantee that it will be respected by the 2o year old paper you have to dig up to understand a phase in a paper.
Apr
24
revised Measuring very long half lives accurately
blue pencil
Apr
24
revised Measuring very long half lives accurately
added 18 characters in body
Apr
24
answered Measuring very long half lives accurately
Apr
24
revised Measuring very long half lives accurately
edited tags
Apr
24
comment Exponentially accelerating universe, dark energy, the universe's temperature and event horizons.. (sorry in advance!)
The site has MathJax active to allow LaTeX-mathmode-alike markup (so $j = \dot{a}$ is written as j = \dot{a} placed inside single dollar-signs. You'll find some links in the sidebar when asking a question. You might start with physics.stackexchange.com/editing-help .
Apr
24
comment Neutrino interaction probability
I all seriousness the best place to start is far enough back that this becomes obvious. But even if you aren't going to do that go back and think hard about the meaning of interaction cross-sections and work from there.
Apr
24
comment Can there be a two-neutron bound state?
Various related (duplicate?) questions: physics.stackexchange.com/q/242604 physics.stackexchange.com/q/202581
Apr
24
revised Can there be a two-neutron bound state?
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Apr
22
comment How far does a photon move in the 4th dimension when it travels one light second?
See the comment above about extended discussion. Hold it in the chat room or not at all.
Apr
22
comment How far does a photon move in the 4th dimension when it travels one light second?
Comments are not for extended discussion; this conversation has been moved to chat.
Apr
22
comment How far does a photon move in the 4th dimension when it travels one light second?
Presumably related to physics.stackexchange.com/q/250303 and therefore to physics.stackexchange.com/q/33840 and the various duplicate thereof.