possible bug in HLLHCEvtVtxGenerator in RF800 mode

[slava77]

#44882

The code in HLLHCEvtVtxGenerator for RF800 mode was introduced in #16942 (@lgray )

cmssw/IOMC/EventVertexGenerators/src/HLLHCEvtVtxGenerator.cc

Lines 195 to 201 in 8c36010

	result =
	norm *
	std::exp(-ct * ct * ct * ct / sigs4 - z * z * z * z * cos2 * cos2 / sigs4 - 6 * ct * ct * z * z * cos2 / sigs4 -
	sin2 / (4 * k2 * sigmax2) *
	(2 + 4 * k2 * z * z - std::cos(2 * k * (z - ct)) - std::cos(2 * k * (z + ct)) -
	8 * k * s * std::cos(k * ct) * std::sin(k * z) - 4 * cosks * cosks * sinct * sinct)) /
	std::sqrt(1 + z * z / (betx * betx)) / std::sqrt(1 + z * z / (bets * bets));

k * s on L200 picks up s = second = 1e9 from CLHEP initially present in the global scope.
all other pairing with k are in units of length (k*ct and k*z).
It looks like s was supposed to be z.

This issue is a followup to the discussion #44882 to check/confirm if this is indeed a bug.

@civanch

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A new Issue was created by @slava77.

@rappoccio, @antoniovilela, @sextonkennedy, @Dr15Jones, @makortel, @smuzaffar can you please review it and eventually sign/assign? Thanks.

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[slava77]

assign simulation

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New categories assigned: simulation

@civanch,@mdhildreth you have been requested to review this Pull request/Issue and eventually sign? Thanks