A dataset provided by the European Space Agency

Name: Verifying A Neutron-Star UCXB Candidate with A Possibly 10.2-min Orbital Period
Published: 2022-04-06T00:00:00Z

Proposal ID	086551
Title	Verifying A Neutron-Star UCXB Candidate with A Possibly 10.2-min Orbital Period
Download Data Associated to the proposal	https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0865510101
DOI	https://doi.org/10.57780/esa-9f3nfdc
Principal Investigator, PI	Dr Hang Gong
Abstract	We have discovered a previously unnoticed X-ray source 3.2$^{circ}$ away fromthe Galactic Center. Its XMM/MOS light curve has a periodic variability at614.28s($approx$3.8$sigma$). Its X-ray spectrum is perfectly described by anabsorbed 1.8keV blackbody plus Fe-line features. It has an $L_{mathrm{X}}$about $1.2times10^{34}times$(D/10 kpc)$^{2}$ erg s$^{-1}$ and has no obviousoptical counterpart(fx/fo$>$1600). We argue it is most likely a neutron-starultra-compact X-ray binary with the shortest orbital period so far. We proposean XMM/PN observation to constrain its nature by: 1) verifying the 614s signaland looking for a possible rotational period, 2)checking its new spectral shapeand whether other spectral components exist with more X-ray photons.
Publications	Discovery of a Compact X-Ray Object with a 614 s Periodicity in the Direction of the Galactic Center \|Gong Hang \| ApJ \| 933-240 \| 2022 \| 2022ApJ...933..240G \| http://ui.adsabs.harvard.edu/#abs/2022ApJ...933..240G From Active Stars to Black Holes: A Discovery Tool for Galactic X-Ray Sources \|Rodriguez Antonio C. \| PASP \| 136-054201 \| 2024 \| 2024PASP..136e4201R \| http://ui.adsabs.harvard.edu/#abs/2024PASP..136e4201R Periodicity from X-ray sources within the inner Galactic disk \|Mondal Samaresh Ponti Gabriele et al. \| A&A \| 686-A125 \| 2024 \| 2024A&A...686A.125M \| http://ui.adsabs.harvard.edu/#abs/2024A&A...686A.125M
Instrument	EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage	2021-03-02T21:31:10Z/2021-03-03T14:59:30Z
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.
Creator Contact	https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk
Date Published	2022-04-06T00:00:00Z
Last Update	2025-01-27
Keywords	"l_ {\ mathrm", "28s $\", "xray photons", "xray spectrum", "614s signal", "perfectly described", "unnoticed xray source", "$\ sigma $.", "times10 ^{", "shortest orbital period", "spectral components exist", "mos light curve", "$^{\ circ }$", "fo $>$ 1600", "spectral shape", "}$ erg", "rotational period", "galactic center", "optical counterpartfx", "orbital period", "x }}$", "XMM", "periodic variability"
Publisher And Registrant	European Space Agency
Credit Guidelines	European Space Agency, Dr Hang Gong, 2022, 'Verifying A Neutron-Star UCXB Candidate with A Possibly 10.2-min Orbital Period', 18.02_20200221_1200, European Space Agency, https://doi.org/10.57780/esa-9f3nfdc