The Cepheid Leavitt law (P-L relation) continues to be a cornerstone ofcosmology. However, the favored implementation in the infrared requires anunderstanding of CircumStellar Envelopes (CSEs) seen around many Cepheids. CSEsmay also hold the key to possible pulsation driven mass-loss, an importantcomponent evolutionary modeling. Recently discovered X-ray bursts modulated bythe pulsation cycle provide a possible link to CSEs. The observations requestedhere will test the link between X-rays and CSEs (Eta Aql), and also theconnection to the ..atmosphere collapse X-ray trigger (Zeta Gem).
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-05-12T02:00:50Z/2019-05-12T22:50:50Z
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, Dr Nancy Remage Evans, 2020, 'Cepheids\: Unraveling Mass Loss and Luminosity', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-3r6f7ic
