WZ Sagittae is the prototype of a subclass of dwarf novae with extremelylong recurrence period. We don.t understand yet how to keep WZ Sge inquiescence for 30 years, unless it has a magnetic white dwarf. Thisseems likely, since there is a 27.87 s periodicity in the optical, UV,and probably in ASCA data. However, the ASCA detection wasn.t asconvincing as we had hoped. Moreover, there are other periodic signalsnear 28 s, which the magnetic white dwarf model struggles to explain,leading to the advent of the pulsating white dwarf model. We proposemultiple XMM-Newton pointings to distinguish between these two models.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2003-05-16T14:52:07Z/2003-05-16T17:37:25Z
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 Koji Mukai, 2004, 'WZ Sagittae in Quiescence: Magnetic or Pulsating White Dwarf', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-ym32j77
