I keep reading the same phrase about the very short life time of the top quark:

Because the t-quark decays on a shorter than the characteristic QCD interaction-time it cannot hadronize. Therefore it give to possibility to be seen as a bare quark.

I cannot find any more information beyond this simple phrase. There are however a few things that I would like to seen cleared out (sorry for the naive questions) :

  • The first question is simple: I don't understand why this offers to opportunity to see a bare quark, since this quark decays that fast it must be very difficult te see it...
  • A bare quark?? I thought this was ruled to see colorful particles?
  • $\begingroup$ Do you know what the word "hadronize" means in this context? $\endgroup$ – dmckee --- ex-moderator kitten Apr 12 '14 at 19:23
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    $\begingroup$ Keep reading where? $\endgroup$ – Qmechanic Apr 12 '14 at 19:25
  • $\begingroup$ You might find the comments under a post where I relayed this tidbit useful. $\endgroup$ – dmckee --- ex-moderator kitten Apr 12 '14 at 19:26
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    $\begingroup$ Quark masses have an anomalous dimension and therefore its definition depends on the renormalization scheme and energy scale considered. Since the top does not hadronize, I think we can probe directly its pole mass. I guess that explains why it called a "bare quark", but I am not completely sure. $\endgroup$ – Melquíades Apr 12 '14 at 21:50

I too see this often, @QMechanic.

See, for example, Griffiths, Introduction to Elementary Particles, pg 47.

By this they mean that the time it would take for signals to cross the 'length' of a typical hardon is much longer than the time it takes for a top (truth!) quark to decay.

Since we assume cuasility, we cannot have an interaction which propagats faster than the limiting speed.

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