Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Medium Modifications from 4He(e,e'p)3H   Polarization transfer in quasi-elastic nucleon knockout is sensitive to the
properties of the nucleon in the nuclear medium, including possible
modification of the nucleon form factor and/or spinor. In our recently
completed experiment E03-104 at Jefferson Lab we measured the proton recoil
polarization in the 4He(e,e'p)3H reaction at a Q^2 of 0.8 (GeV/c)^2 and 1.3
(GeV/c)^2 with unprecedented precision. These data complement earlier data
between 0.4 and 2.6 (GeV/c)^2 from both Mainz and Jefferson Lab. The measured
ratio of polarization-transfer coefficients differs from a fully relativistic
calculation, favoring either the inclusion of a medium modification of the
proton form factors predicted by a quark-meson coupling model or strong
charge-exchange final-state interactions. The measured induced polarizations
agree well with the fully relativistic calculation and indicate that these
strong final-state interactions may not be applicable.

8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
2
The categories of this paper are: math
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn