HST spectrum and timing of the ultracompact X-ray binary candidate 47 Tuc X9
dc.contributor.author | Tudor, V. | |
dc.contributor.author | Miller-Jones, James | |
dc.contributor.author | Knigge, C. | |
dc.contributor.author | Maccarone, T. | |
dc.contributor.author | Tauris, T. | |
dc.contributor.author | Bahramian, A. | |
dc.contributor.author | Chomiuk, L. | |
dc.contributor.author | Heinke, C. | |
dc.contributor.author | Sivakoff, G. | |
dc.contributor.author | Strader, J. | |
dc.contributor.author | Plotkin, R. | |
dc.contributor.author | Soria, R. | |
dc.contributor.author | Albrow, M. | |
dc.contributor.author | Anderson, G. | |
dc.contributor.author | van den Berg, M. | |
dc.contributor.author | Bernardini, F. | |
dc.contributor.author | Bogdanov, S. | |
dc.contributor.author | Britt, C. | |
dc.contributor.author | Russell, D. | |
dc.contributor.author | Zurek, D. | |
dc.date.accessioned | 2018-06-29T12:28:37Z | |
dc.date.available | 2018-06-29T12:28:37Z | |
dc.date.created | 2018-06-29T12:08:51Z | |
dc.date.issued | 2018 | |
dc.identifier.citation | Tudor, V. and Miller-Jones, J. and Knigge, C. and Maccarone, T. and Tauris, T. and Bahramian, A. and Chomiuk, L. et al. 2018. HST spectrum and timing of the ultracompact X-ray binary candidate 47 Tuc X9. Monthly Notices of the Royal Astronomical Society. 476 (2): pp. 1889-1908. | |
dc.identifier.uri | http://hdl.handle.net/20.500.11937/69141 | |
dc.identifier.doi | 10.1093/mnras/sty284 | |
dc.description.abstract |
To confirm the nature of the donor star in the ultracompact X-ray binary candidate 47 Tuc X9, we obtained optical spectra (3000–10 000 Å) with the Hubble Space Telescope / Space Telescope Imaging Spectrograph. We find no strong emission or absorption features in the spectrum of X9. In particular, we place 3σ upper limits on the H α and He ii λ4686 emission line equivalent widths − EWH α ≲ 14 Å and −EW HeII ≲9 −EWHeII≲9 Å, respectively. This is much lower than seen for typical X-ray binaries at a similar X-ray luminosity (which, for L 2--10keV ≈10 33 --10 34 L2--10keV≈1033--1034 erg s−1 is typically − EWH α ∼ 50 Å). This supports our previous suggestion, by Bahramian et al., of an H-poor donor in X9. We perform timing analysis on archival far-ultraviolet, V- and I-band data to search for periodicities. In the optical bands, we recover the 7-d superorbital period initially discovered in X-rays, but we do not recover the orbital period. In the far-ultraviolet, we find evidence for a 27.2 min period (shorter than the 28.2 min period seen in X-rays). We find that either a neutron star or black hole could explain the observed properties of X9. We also perform binary evolution calculations, showing that the formation of an initial black hole/ He-star binary early in the life of a globular cluster could evolve into a present-day system such as X9 (should the compact object in this system indeed be a black hole) via mass-transfer driven by gravitational wave radiation. | |
dc.publisher | Oxford University Press | |
dc.relation.sponsoredby | http://purl.org/au-research/grants/arc/FT140101082 | |
dc.title | HST spectrum and timing of the ultracompact X-ray binary candidate 47 Tuc X9 | |
dc.type | Journal Article | |
dcterms.source.volume | 476 | |
dcterms.source.number | 2 | |
dcterms.source.startPage | 1889 | |
dcterms.source.endPage | 1908 | |
dcterms.source.issn | 0035-8711 | |
dcterms.source.title | Monthly Notices of the Royal Astronomical Society | |
curtin.note |
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. | |
curtin.department | Curtin Institute of Radio Astronomy (Physics) | |
curtin.accessStatus | Open access |