| Proposal ID | 069068 |
| Title | The Drop in X-ray Flux at Spectral Type B1:Evidence for a B-Star Dividing Line? |
| Download Data Associated to the proposal | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0690680101 |
| DOI | https://doi.org/10.5270/esa-hoe7fom |
| Principal Investigator, PI | Dr Wayne Waldron |
| Abstract | All B star luminosity classes show a substantial drop in their X-ray emissionbetween spectral type B1 and B2 suggesting an H-R diagram B-star dividing linesomewhat analogous to the one for K giants. This emission appears to be relatedto the bi-stability jump at spectral type B1. But our analyses of B supergiantand giant XMM data revealed several interesting and unexpected results that donot support theoretical predictions. There seems to be a fundamental, unknown,underlying process at work in this spectral region. We now wish to extent ourstudy by requesting XMM EPIC observations of 4 B main sequence stars and 1additional B giant to help us explain the abrupt X-ray changes that areoccurring in this intriguing region of the H-R diagram. |
| Publications |
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| Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
| Temporal Coverage | 2012-07-06T12:24:58Z/2013-03-21T11:21:59Z |
| 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 | 2014-04-03T00:00:00Z |
| Last Update | 2025-01-27 |
| Keywords | "main sequence stars", "star luminosity classes", "bi stability jump", "EPIC", "emission appears", "star dividing line", "requesting xmm epic", "spectral region", "substantial drop", "xray flux", "xray emission", "XMM", "spectral type b1", "giant xmm data", "intriguing region", "abrupt xray" |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, Dr Wayne Waldron, 2014, 'The Drop in X-ray Flux at Spectral Type B1:Evidence for a B-Star Dividing Line?', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-hoe7fom |