|Title||A search for a spinning white dwarf companion in Gamma-Cas-analogs|
|Author||Dr Christian Motch|
|Description||The origin of the hard X-ray spectrum emitted by Gamma-Cas remains a puzzle. Both a white dwarf accreting from the Be star circumstellar disc or magnetic interaction between the photosphere and the disc can explain the unusually hard X-ray emission. The recent discovery of several new G-Cas analogs offers new opportunities to address this problem. XMM-Newton observations of two G-Cas analogs, HD161103 and HD119682 revealed evidences of periodic modulations of the X-ray flux apparently stronger than in G-Cas itself. We propose to re-observe these two sources in order to confirm or not the stability of the period. Establishing the presence of a stable pulsation in any of these G-Cas analogs would be a major step forward in our understanding of the whole class.|
|Publication||No observations found associated with the current proposal|
|Instrument||EMOS1, EMOS2, EPN, OM, RGS1, RGS2|
|Mission Description||The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's 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 Earth's 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.
|Publisher And Registrant||European Space Agency|
|Credit Guidelines||European Space Agency, 2010-03-26T00:00:00Z, 055100, 17.56_20190403_1200. https://doi.org/10.5270/esa-k0029hp|