In solar-type stars, rotational shear at the tachocline is thought to power adynamo, generating a magnetic field that heats the star.s corona, which producesX-rays. X-ray flux and rotation rates measurements therefore provide insightinto the strength of the underlying magnetic field and its dependence onrotation. But this rotation-activity relation remains unconstrained for theslowest rotators (i.e., Rossby number > 0.8). We propose to observe six700-Myr-old solar-type slowly rotating Praesepe stars, for a total of 157 ks ofexposure with the EPIC camera. Our data will provide invaluable information onthe rotation-activity relation for the slow rotators, enabling tests of dynamotheory in a largely unconstrained regime.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2021-04-11T06:04:08Z/2021-04-11T14:57:28Z
Version
19.16_20210326_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, Dr Alejandro Nunez, 2022, 'Testing Models for Stellar Magnetic Dynamos with Slow Rotators in Praesepe', 19.16_20210326_1200, European Space Agency, https://doi.org/10.57780/esa-tdu1pj2
