A dataset provided by the European Space Agency

Name: Long-term phase-connected timing of the unique X-ray binary HD49798
Published: 2019-11-23T23:00:00Z

Proposal ID	082022
Title	Long-term phase-connected timing of the unique X-ray binary HD49798
Download Data Associated to the proposal	https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0820220101 https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0820220201
DOI	https://doi.org/10.5270/esa-sk20he0
Principal Investigator, PI	Dr SANDRO MEREGHETTI
Abstract	HD49798/RX J0648.0-4418 is the only known X-ray binary in which the donor is ahot subdwarf of O spectral type. The compact object (a white dwarf or a neutronstar) has a spin period of 13.2 s and has been steadily spinning up at2x10^{-15} s/s for the last 20 years. Independently of its NS or WD nature, thisspin-up is difficult to explain with the angular momentum that accretion cansupply. An alternative explanation requires the presence of a young WD, still incontracting phase. We propose a fulfil observation to extend the phase connectedtiming solution in order to investigate the timing properties of this uniquebinary and shed light on the nature of the compact object.
Publications	Hot subdwarf wind models with accurate abundances. I. Hydrogen dominated stars HD 49798 and BD+18\\u00b0 2647 \|Krti\\u010dka, J., Jan\\u00edk, J., et al. \| A&A \| 631-75 \| 2019 \| 2019A&A...631A..75K \| http://ui.adsabs.harvard.edu/#abs/2019A&A...631A..75K New X-ray observations of the hot subdwarf binary HD 49798/RX J0648.0-4418 \|Mereghetti, S., Pintore, F., et al. \| MNRAS \| 504-920 \| 2021 \| 2021MNRAS.504..920M \| http://ui.adsabs.harvard.edu/#abs/2021MNRAS.504..920M Timing the X-ray pulsating companion of the hot subdwarf HD 49798 with NICER \|Rigoselli, Michela, De Grandis, Davide, et al. \| MNRAS \| 523-3043 \| 2023 \| 2023MNRAS.523.3043R \| http://ui.adsabs.harvard.edu/#abs/2023MNRAS.523.3043R The XMM-Newton Line Emission Analysis Program (X-LEAP). I. Emission-line Survey of O VII, O VIII, and Fe L-shell Transitions \|Pan, Zeyang, Qu, Zhijie, et al. \| ApJS \| 271-62 \| 2024 \| 2024ApJS..271...62P \| http://ui.adsabs.harvard.edu/#abs/2024ApJS..271...62P
Instrument	EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage	2018-11-08T10:20:38Z/2018-11-08T23:47:51Z
Version	PPS_NOT_AVAILABLE
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	2019-11-23T23:00:00Z
Keywords	"alternative explanation", "phase connected", "term phase connected", "xray binary", "rx j0648", "angular momentum", "shed light", "neutron star", "hot subdwarf", "steadily spinning", "spectral type", "xray binary hd49798", "white dwarf", "spin period", "compact object", "2x10 ^{", "J0648.0", "contracting phase"
Publisher And Registrant	European Space Agency
Credit Guidelines	European Space Agency, Dr SANDRO MEREGHETTI, 2019, 'Long-term phase-connected timing of the unique X-ray binary HD49798', PPS_NOT_AVAILABLE, European Space Agency, https://doi.org/10.5270/esa-sk20he0