We address two galaxy formation issues by studying the hot gas around theedge-on spiral NGC891. The primary issue is the origin of the hot halo, whichcan occur by infall onto the galaxy or from a galactic fountain generated bydisk SNe. We differentiate between models by measuring the gas metallicity,predicted to be low in one model and high in the other. Second, we will measurethe vertical component of the galaxy.s gravitational field, thereby lifting adegeneracy in mass models and permitting a unique determination of the darkmatter density in the baryon-dominated region. We accomplish this by measuringthe temperature and emission measure distribution perpendicular to the disk.Existing data prove feasibility but are not sufficiently deep.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2011-08-25T23:46:54Z/2011-08-27T12:41:56Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Prof Joel Bregman, 2012, 'Galactic Fountains comma Galaxy Infall comma and the Dark Matter Content of NGC 891', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-80y5p6k
