Have the $W_0$, $W_1$, $W_2$ and $B$ bosons of Electroweak fame ever been discovered experimentally? I have read that the LHC, and perhaps other collides, have reached so-called electroweak energies, where the two forces are unified....
So how much energy, exactly, is needed to produce fields/particles like those that existed during the Electroweak Epoch of the early universe?
And have the W0....W3? and B bosons actually been officially 'observed'?
 A: Well, the popular science bloviations rarely mean anything to me, as they are pitched to impress the public with large numbers in unfamiliar units.
The electroweak scale is v=0.245 TeV, ~$2m_H$, corresponding to a temperature of ~ 2$\cdot 10^{12}$ K.
So I gather you are pointing out that the maximum LHC energy, 50 times that, should perhaps suffice to make the W&Z masses irrelevant, in some vague sense. But, in each isolated event, the vector bosons, W&Z, travel "huge" distances in our normal (post SSB, low energy) EW vacuum, before they decay and have their products reach the detectors, so what is observed (indirectly) is W&Zs.
The way I reconstruct/deconstruct your question is "can the precursors of those, $W_{1,2,3}$ & B, traveling in an effective collision fireball hotter than v be somehow inferred, before they leave that medium/vacuum and 'turn' into the 'detected' W&Z?".
I fear the question is intrinsically vague, and I have no good answer to it. The pre-SSB vacuum only obtains in the isolated "fireball" of each (rare) event, not in an extensive primordial soup.
Everything detected so far at ATLAS & CMS, to my limited knowledge, comports pretty well with the SM and its subtle predictions of the equivalence theorem for the EW interactions.
This is the systematic framework probing your massless pre-SSB bosons inside the belly of the W&Z, and parsing out the eaten goldstons in suitable amplitudes: i.e., there are small factors with v/E, so, $m_{W,Z}/E$, and they appear to be increasingly weaker at higher energies, probably borne out by the data... but maybe this is wishful thinking.
Perhaps an experimentalist could point you to a review of such. So such processes might indicate the underlying presence of $W_{1,2,3}$&B, anfractuously.
The theorist's point of view is that pre- and post-SSB variables are all equivalent, and your choosing such is a matter of convenience. The "actual" bosons "detected" in a chain of indirection, are always the massive W&Z with propagate massively in our "low-energy" vacuum.
A: The $W$ and $B$ fields are just linear combinations of the post-SSB fields, it's simply a choice of basis.
