PhD ceremony: Mr. T.P.K. Martinsson, 16.15 uur, Aula Academiegebouw, Broerstraat 5, Groningen
Dissertation: The distribution of mass with spiral galaxies. Unique solutions from gas and stellar kinematics
Promotor(s): prof. M.A.W. Verheijen
Faculty: Mathematics and Natural Sciences
This thesis investigates the amount and distribution of dynamically distinct components such as stars, gas, and dark matter, in thirty spiral galaxies similar to our own Milky Way, with direct implications for our general understanding of the formation and evolution of galaxies. With optical and radio spectroscopy, I have measured the total dynamical mass of each galaxy based on the rotation speed of the disk. The total mass of a galaxy's disk component follows from the measured random motions of the stars while the masses of the atomic and molecular gas disks follow directly from their emission in the infrared and radio regions of the electromagnetic spectrum. The mass and distribution of the dark matter is then calculated by considering the difference between the total dynamical mass and the mass of the visible components. Contrary to what is commonly assumed, I have found that dark matter is an important and often dominant mass component even in the most luminous, central regions of spiral galaxies. On average, the visible components of spiral galaxies contribute approximately 30 percent to the total mass within a radius comparable to that of the orbit of the Sun in our Milky Way galaxy; the remaining 70 percent of the mass is dark. This implies that the luminous mass of disk galaxies is approximately three times lower than commonly assumed.
Carmem M. Gilardoni wins the Ehrenfest-Afanassjewa thesis prize 2022
Hanneke Siebe is working on a fullly sustainable paint, based on gum arabic.
On the 12th of January a large number of parties involved in the development of batteries in the Netherlands – small companies, multinationals and knowledge institutes – attended the kick off of the BatteryNL consortium. Their goal is to develop the...
The UG website uses functional and anonymous analytics cookies. Please answer the question of whether or not you want to accept other cookies (such as tracking cookies).
If no choice is made, only basic cookies will be stored. More information