Proposal ID | 072354 |
Title | The Secret Lives of Cepheids: Exploring the X-ray Variability of delta Cep |
Download Data Associated to the proposal | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0723540301 |
DOI | https://doi.org/10.5270/esa-amro4ri |
Principal Investigator, PI | Prof Edward Guinan |
Abstract | 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 completeX-ray phase coverage for this important star, which shows well-defined phasedchanges of FUV emission line fluxes from hot (10,000 300,000 K) plasmas. Theemissions peak between pulsation phases 0.75 1.05 and likely originate frompulsation-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 shouldpeak. These phases were not previously covered by XMM. The requestedobservations will provide crucial tests of atmospheric heating theories for Cepheids. |
Publications |
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Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
Temporal Coverage | 2013-06-28T06:11:55Z/2013-07-03T08:00:22Z |
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. |
Creator Contact | https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk |
Date Published | 2014-09-01T00:00:00Z |
Last Update | 2025-01-27 |
Keywords | "phase range", "atmospheric heating theories", "EPIC", "classical cepheids", "xray emissions", "xmm newton epic", "delta cep", "secret lives", "pulsation phases", "defined phased", "complement existing", " 948", "emissions peak", "XMM", "xray variability", "variable xray", "pulsation induced shoc", "HST" |
Publisher And Registrant | European Space Agency |
Credit Guidelines | European Space Agency, Prof Edward Guinan, 2014, 'The Secret Lives of Cepheids: Exploring the X-ray Variability of delta Cep', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-amro4ri |