tau Boo is the first star other than the Sun which has been observed to have aglobal magnetic field with switching polarity. In contrast to the Sun, tau Boo.smagnetic cycle has a duration of only two years. In the previous AO, we wereawarded four EPIC pointings of 8 ks each to monitor tau Boo.s activity inX-rays, backing up our observations with optical measurements of thechromospheric activity as well as Zeeman Doppler Imaging. We propose to continuemonitoring the star during this AO with XMM-Newton for a total of 32 ks as wellas with Chandra for a total of 10 ks to gain more insight into the stellaractivity cycle by comparing X-ray luminosities and coronal temperatures derivedfrom the CCD spectra to the chromospheric activity profile and the magnetic field configuration of tau Boo.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2011-06-19T10:48:00Z/2012-01-20T23:07:09Z
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, Mrs Katja Poppenhaeger, 2013, 'tau Boo.s magnetic polarity switch in X-rays - continued monitoring', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-3vn34kl
