Gamma-Cas analogs are early Be stars displaying very unusual hard X-ray emissionwith a luminosity intermediate between normal massive stars and XRBs. Both anunexpected magnetic activity in a critically rotating star, or accretion in a Be+ white dwarf (or neutron star) binary, have been invoked to account for theseoutstanding features. We request follow-up observations to better characterisethe high-energy properties (X-ray temperatures, local absorption and variabilitypatterns) of those Gamma-Cas analogs and candidate analogs lacking sensitiveenough observations. The overall data set will allow us to bring strongerconstraints on the X-ray emitting mechanism.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-03-22T10:19:37Z/2020-04-05T19:01:41Z
Version
18.02_20200221_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 Christian Motch, 2021, 'Follow-up observations of Gamma-Cas analogs', 18.02_20200221_1200, European Space Agency, https://doi.org/10.5270/esa-2ly098h
