RHESSI observations of galactic nuclear lines

The Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) contains nine large, high-resolution germanium gamma-ray detectors, and has been in low-Earth orbit since February, 2002. Since RHESSI's detectors are unshielded, they detect gamma radiation from most of the sky at any given moment (whatever is unblocked by the Earth). We have been using RHESSI to study lines from recently synthesized radioactive nuclei in the Galaxy. We will present the latest results on: 1) the line from Galactic 26Al (which RHESSI detects at very high significance); 2) the lines from Galactic 60Fe (which are detected for the first time, but only at marginal significance); and 3) the lines of 44Ti which are known to be present in the Cas A supernova remnant. We will also discuss the search for flashes of positron annihilation in the earliest stages of classical novae.