Extraction of the RatioF2n/F2p

Abstract

The ratio of the deuteron to proton structure functions is measured at very small Bjorken x (down to 10 6) and for Q ) 0.001 GeV2 from scattering of 470 GeV muons on liquid hydrogen and deuterium targets. The ratio F2/F2 extracted from these measurements is found to be constant, at a value of

The range of validity of the QCD-improved parton model

“…Taking into account uncertainty of F n 2 /F p 2 at its upper limit should allow us to prove our thesis about the IPM breaking with a bigger degree of reliability. We have checked that in the interesting kinematical range the used parametrization is consistent within experimental uncertainties with the E665 [13] data for F d 2 /F p 2 . The world data on F p 2 and F d 2 from the compilation [14] was taken in the present analysis.…”

A small target neutrino deep-inelastic scattering experiment at the first muon collider

“…Such a measurement would either confirm or challenge our assumptions about isospin symmetry. The effects seen in charged lepton scattering are large; for example, 2F d 2 /F p 2 − 1 is 0.935 ± 0.008(stat) ± 0.034(syst) at x below 0.01 [9], and at higher x this ratio is even farther away from unity. With hydrogen and deuterium targets of the sizes suggested above one would have enough statistics to measure the quantity 2xF d 3 /xF p 3 −1 as a function of x to better than a per cent, over a reasonably large x range.…”

“…Large low-Z targets have already been used successfully by muon scattering experiments. The sizes of liquid hydrogen targets are in general limited by safety considerations, and a liquid hydrogen target of 1m thickness and radius approximately 10 cm has been used by experiment E665 at Fermilab [9]. A target of this volume of hydrogen with a 20 cm radius would have a thickness of 1.75g/cm 2 , resulting in data samples of slightly over a million ν charged current events per year.…”

“…Charged lepton experiments have studied nuclear dependences of the structure function F 2 and have seen a sizeable effect [10] [9], yet no nuclear dependences have been seen in xF 3 , and for now theory must only assume that the integral of the valence quark distribution is independent of nuclear corrections. By scattering neutrinos off several light targets one could finally determine whether or not valence quarks know anything about what kind of nucleus they are in.…”

Deuteron structure functions in the context of few-body physics

“…Subtracting the shadowing correction from the deuteron data should then yield F p 2 − F n 2 → 0 as x → 0. While for the lowest NMC data point it may be debatable whether the Regge region is reached, the E665 Collaboration [68] has taken data to very low x, x ∼ 10 −5 , which should be much nearer the onset of Regge behavior.…”