Thomas Bensby

I will present the results of our investigation of the Gaia Phase Spiral using Gaia Data Release 3. The phase spiral is a pattern in the plane defined by the vertical velocity (VZ) and vertical distance from the Galactic plane (Z). We have been able to determine the phase spiral's orientation and strength, or amplitude, at different locations in the Galactic disc by using a model we developed for characterising the phase spiral. We have determined the rate of rotation of the phase spiral with Galactic azimuth and radius, finding that it changes like disturbance propagating through the disc. We have also found that the phase spiral is significantly stronger in a range of angular momenta in the outer disc than in the solar neighbourhood but then weakens further out in the disc. There is much to learn about the historical events which have shaped our Galaxy. Using Gaia data to investigate the phase spiral, we hope to better understand these processes.