Superscaling of inclusive electron scattering from nuclei

Abstract

We investigate the degree to which the concept of superscaling, initially developed within the framework of the relativistic Fermi gas model, applies to inclusive electron scattering from nuclei. We find that data obtained from the low energy loss side of the quasielastic peak exhibit the superscaling property, i.e. the scaling functions f (ψ ′ ) are not only independent of momentum transfer (the usual type of scaling: scaling of the first kind), but coincide for A ≥ 4 when plotted versus a dimensionless scaling variable ψ ′ (scaling of the second kind). We use this behavior to study as yet poorly understood properties of the inclusive response at large electron energy loss.

Scaling and isospin effects in quasielastic lepton–nucleus scattering in the relativistic mean field approach

“…On the contrary, the transverse contribution f T (ψ ) overestimates the data by ∼ 20% even in the region close to the maximum, ψ ≈ 0. This result, arising from zeroth-kind scaling violation in the RMF approach, is not in conflict with (e, e ) data that indeed leaves room for effects of this type (see the general discussion in [3,4]). …”

“…The data analysis of the separated longitudinal (L) and transverse (T ) contributions to the scaling function carried out in [3,4] has shown that, whereas the L response does scale to a universal curve, the T strength increases with the transfer momentum q and/or the mass number A. This excess of strength in the transverse channel is not entirely understood, although different effects ranging from FSI effects to MEC contributions have been invoked to explain it.…”

“…Extensive analyses of quasielastic (QE) inclusive electron scattering data performed in recent years [1][2][3][4] have clearly demonstrated the quality of the behavior known as scaling. These analyses are based on the so-called superscaling function, f (ψ ), obtained by dividing the cross section by an appropriate function which contains the single nucleon physics, and plotting the result against the scaling variable ψ (q, ω) (see, e.g., [5]).…”

Influence of nucleonic motion in relativistic Fermi gas inclusive responses

“…which scales in the region where the RFG is expected to be a reasonable model, specifically at q > 2p F where Pauli blocking effects are absent [4,5,6]. That is, it depends only upon a single variable ψ, whose square is given by…”

Nuclear effects in (anti)neutrino charge-current quasielastic scattering at MINER νA kinematics

“…The theoretical concept of superscaling has been introduced within the relativistic Fermi gas (RFG) model [21,22]. In the RFG model the scaling function f RFG (ψ ) = k F · F has the form [23]: As pointed out in [23], however, the actual dynamical physical reason of the superscaling is more complex than that provided by the RFG model. In Ref.…”