Ongoing studies of magnetic activity at the end of the stellar main-sequencehave revealed an emerging dichotomy in the X-ray and radio properties. Thehetero- geneous properties of ultracool dwarfs (spectral type M7 and later)display either strong coronal-like X-rays with low radio luminosities orpredominantly planet-like strong radio emissions with weak X-ray luminosities.This bifurcation is likely driven by the properties of the magnetic field andthe stellar rotation. We will explicitly test this hypothesis by filling theparameter space with a TESS-selected sample\: The new TESS rotation period willbe complemented here with both radio and X-ray data spanning the rotation periodthreshold across which the dichotomy appears.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2020-06-22T23:51:37Z/2020-11-19T00:45:24Z
Version
18.02_20200221_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 Beate Stelzer, 2021, 'X-ray emission of ultracool dwarfs across the radio-loud - radio-quiet boundary', 18.02_20200221_1200, European Space Agency, https://doi.org/10.57780/esa-9m6xjic
