|Title||X-ray counterpart of the shortest activity cycle found to date|
|Author||Dr Jorge Sanz-Forcada|
|Description||Activity cycles are commonly found among late type stars through the chromospheric CaII emission. Their coronal counterpart, however, remains elusive in most cases, despite of the clear cycle observed in the solar corona, spanning as much as 1.7 dex in Lx. The recent discovery of a CaII cycle in HR 810 of just 1.6 yr, the shortest to date, offers a unique opportunity to test the existence of an X-ray counterpart of the cycle within one or at most two XMM-Newton observing periods. The star offers also two more attractives: with an age of only 500 Myr and spectral type G0V it represents a young solar analog, and a planet of 1.9 Mj orbits the star at 0.9 a.u. We intend to make 8 snapshots during AO10, for a total of 40 ks, to cover 60% of the cycle starting near its lowest level of activity.|
|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, 2013-03-03T00:00:00Z, 067361, 17.56_20190403_1200. https://doi.org/10.5270/esa-5kbrts4|