Suppression of star formation in early-type galaxies by feedback from supermassive black holes.

Detailed high-resolution observations of the innermost regions of nearby galaxies have revealed the presence of supermassive black holes. These black holes may interact with their host galaxies by means of 'feedback' in the form of energy and material jets; this feedback affects the evolution of the host and gives rise to observed relations between the black hole and the host. Here we report observations of the ultraviolet emissions of massive early-type galaxies.

The Detection of Multimodal Oscillations on alpha Ursae Majoris.

We have used the star camera on the Wide-Field Infrared Explorer satellite to observe the K0 III star alpha UMa, and we report the apparent detection of 10 oscillation modes. The lowest frequency mode is at 1.82 µHz, and it appears to be the fundamental mode.

Evolutionary Model and Oscillation Frequencies for alpha Ursae Majoris: A Comparison with Observations.

Inspired by the observations of low-amplitude oscillations of alpha Ursae Majoris A by Buzasi et al. using the WIRE satellite, a grid of stellar evolutionary tracks has been constructed to derive physically consistent interior models for the nearby red giant. The pulsation properties of these models were then calculated and compared with the observations.