We propose XMM observations of two Classical Cepheids to confirm X-ray variability in beta Dor and to detect RT Aur. The data will complement our existing XMM data and HST UV spectroscopy for Dor, whose UV emissions show phased variabili tyfrom hot plasmas. The UV emissions peak between phases 0.7-0.8p and originatefrom pulsation-induced shocks. We request three 40-ksec exposures of beta Dor to complete its X-ray light curve and confirm the enhanced activity around 0.5p observed in our previous XMM data. If confirmed, the X-ray phasing will contrastthe UV emissions, providing vital information on the atmospheric heating mechanism(s). We also propose a 30-ksec observation of the nearby Cepheid RT Aur to search for X-ray activity and expand the Cepheid X-ray Inventory parameter space.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2015-05-25T23:14:08Z/2015-09-15T01:34:53Z
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, Prof Edward Guinan, 2016, 'Exposing the Secret X-ray Lives of Cepheids with XMM-Newton', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-s8rorp3
