Cataclysmic variables (CVs) evolve from longer to shorter orbital periods untila minimum period P_min is reached. Approaching the short period end of the CVorbital period distribution, the mass-transfer rate is decreasing but nevervanishes. However, the previously active dwarf nova HO Cet, which orbital periodP_orb is very close to P_min, displays excellent evidence for extremely lowmass-transfer rate, much lower than in all previously known CVs. Is themass-transfer in HO Cet terminated completely or its rate is very low but thedonor star is still transferring matter?. In this proposal we aim to findevidence for still ongoing accretion in HO Cet through the detection of theobject in X-rays. The cessation of mass-transfer is not consistent with prior theory and observations.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-07-15T14:07:44Z/2019-07-15T16:21:04Z
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 Vitaly Neustroev, 2020, 'A possible cessation of mass-transfer in previously active cataclysmic variable', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-ys7mc3j
