in this category [@metag] involves the in-medium $\omega$ meson in +A+X\^0+ X\^.\[Metag\] The coupling $\omega\pi^0\gamma$ is significant in that it arises from a chiral anomaly and is expected to behave differently in medium from that of the normal process (\[V\]) as certain anomalous processes (e.g., those involving triangle diagrams) are.

Off-shell probes
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There are indirect probes that indicate how hadron masses and coupling constants behave in dense medium. A recent discussion on this matter can be found in the review by Brown et al [@BHLR06]. Most of the relevant arguments given there have been developed in a series of articles that date way back to early 1990’s [@BR:PR].

If one looks for a signal at zero temperature but at a matter density near that of the normal nuclear matter, then the mass scaling (n)=m\^\*/m m(n)/m(0) is a $parameter$ in an effective theory because what one is dealing with here is an off-shell quantity. It can however be related to the quark condensate, albeit indirectly, and hence could signal for a chiral symmetry manifestation. In order to “see" the effect in an unambiguous way, one would have to formulate the effective theory in a way consistent with chiral symmetry [*for 