|Title||The Secret Lives of Cepheids: Exploring the X-ray Variability of delta Cep|
|Author||Prof Edward Guinan|
|Description||We propose XMM-NEWTON EPIC observations of the prototype of Classical Cepheids, δ Cep, that we discovered is a variable X-ray and FUV emission-line star. The data will complement existing - approved HST FUV spectroscopy and complete X-ray phase coverage for this important star, which shows well-defined phased changes of FUV emission line fluxes from hot (10,000 300,000 K) plasmas. The emissions peak between pulsation phases 0.75 1.05 and likely originate from pulsation-induced shocks. We request two 90 ksec exposures of δ Cep, covering the critical phase range of ~0.5 1.0, where X-ray emissions should peak. These phases were not previously covered by XMM. The requested observations will provide crucial tests of atmospheric heating theories for Cepheids.|
|Publication||Discovery of the Hard Spectrum VHE gamma-Ray Source HESS J1641-463 . Abramowski, A., Aharonian, F., et all. . ApJ . 794-1 . 2014 . 2014ApJ...794L...1A ,
The Secret Lives of Cepheids: A Multi-Wavelength Study of the Atmospheres and Real-Time Evolution of Classical Cepheids . Engle, Scott, . PhDT . 0-45 . 2015 . 2015PhDT........45E ,
The Million Optical - Radio-X-ray Associations (MORX) Catalogue . Flesch, Eric W., . PASA . 33-52 . 2016 . 2016PASA...33...52F ,
The Secret Lives of Cepheids: delta Cep---The Prototype of a New Class of Pulsating X-Ray Variable Stars . Engle, Scott G., Guinan, Edward F., et all. . ApJ . 838-67 . 2017 . 2017ApJ...838...67E ,
|Instrument||EMOS1, EMOS2, EPN, OM, RGS1, RGS2|
|Mission Description||The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's 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 Earth's 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.
|Publisher And Registrant||European Space Agency|
|Credit Guidelines||European Space Agency, 2014-09-01T00:00:00Z, 072354, 17.56_20190403_1200. https://doi.org/10.5270/esa-amro4ri|