A rapid optical and X-ray timing study of the neutron star X-ray binary Swift J1858.6−0814
dc.contributor.author | Shahbaz, T. | en |
dc.contributor.author | Paice, J. A . | en |
dc.contributor.author | Rajwade, K. M. | en |
dc.contributor.author | Veledina, A. | en |
dc.contributor.author | Gandhi, P. | en |
dc.contributor.author | Dhillon, V. S. | en |
dc.contributor.author | Marsh, T. R. | en |
dc.contributor.author | Littlefair, S. | en |
dc.contributor.author | Kennedy, Mark R. | en |
dc.contributor.author | Breton, R. P. | en |
dc.contributor.author | Clark, C. J. | en |
dc.contributor.funder | Horizon 2020 | en |
dc.contributor.funder | Irish Research Council | en |
dc.contributor.funder | Ministerio de Ciencia, Innovación y Universidades | en |
dc.contributor.funder | Science and Technology Facilities Council | en |
dc.date.accessioned | 2023-06-22T15:24:23Z | |
dc.date.available | 2023-06-22T15:24:23Z | |
dc.date.issued | 2023-01-14 | en |
dc.description.abstract | We present a rapid timing analysis of optical (HiPERCAM and ULTRACAM) and X-ray (NICER) observations of the X-ray transient Swift J1858.6−0814 during 2018 and 2019. The optical light curves show relatively slow, large amplitude (∼1 mag in gs) ‘blue’ flares (i.e. stronger at shorter wavelengths) on time-scales of ∼minutes as well as fast, small amplitude (∼0.1 mag in gs) ‘red’ flares (i.e. stronger at longer wavelengths) on time-scales of ∼seconds. The ‘blue’ and ‘red’ flares are consistent with X-ray reprocessing and optically thin synchrotron emission, respectively, similar to what is observed in other X-ray binaries. The simultaneous optical versus soft- and hard-band X-ray light curves show time- and energy-dependent correlations. The 2019 March 4 and parts of the June data show a nearly symmetric positive cross-correlations (CCFs) at positive lags consistent with simple X-ray disc reprocessing. The soft- and hard-band CCFs are similar and can be reproduced if disc reprocessing dominates in the optical and one component (disc or synchrotron Comptonization) dominates both the soft and hard X-rays. A part of the 2019 June data shows a very different CCFs. The observed positive correlation at negative lag in the soft band can be reproduced if the optical synchrotron emission is correlated with the hot flow X-ray emission. The observed timing properties are in qualitative agreement with the hybrid inner hot accretion flow model, where the relative role of the different X-ray and optical components that vary during the course of the outburst, as well as on shorter time-scales, govern the shape of the optical/X-ray CCFs. | en |
dc.description.sponsorship | Ministerio de Ciencia, Innovación y Universidades (PID2020-114822GB-I00); Science and Technology Facilities Council (Grant ST/T000406/1); Irish Research Council (GOIPD/2021/670: Invisible Monsters) | en |
dc.description.status | Peer reviewed | en |
dc.description.version | Published Version | en |
dc.format.mimetype | application/pdf | en |
dc.identifier.citation | Shahbaz, T., Paice, J. A., Rajwade, K. M., Veledina, A., Gandhi, P., Dhillon, V. S., Marsh, T. R., Littlefair, S., Kennedy, M. R., Breton, R. P. and Clark, C. J. (2023) 'A rapid optical and X-ray timing study of the neutron star X-ray binary Swift J1858. 6–0814', Monthly Notices of the Royal Astronomical Society, 520(1), pp. 542–559. doi: 10.1093/mnras/stad163 | en |
dc.identifier.doi | 10.1093/mnras/stad163 | en |
dc.identifier.eissn | 1365-2966 | en |
dc.identifier.endpage | 559 | en |
dc.identifier.issn | 0035-8711 | en |
dc.identifier.issued | 1 | en |
dc.identifier.journaltitle | Monthly Notices of the Royal Astronomical Society | en |
dc.identifier.startpage | 542 | en |
dc.identifier.uri | https://hdl.handle.net/10468/14688 | |
dc.identifier.volume | 520 | en |
dc.language.iso | en | en |
dc.publisher | Oxford University Press | en |
dc.relation.project | info:eu-repo/grantAgreement/EC/H2020::ERC::ERC-ADG/694745/EU/Discovering Fast Transients and Pulsars with MeerKAT for Cosmology and to Test the Laws of Gravity/MeerTRAP | en |
dc.relation.project | info:eu-repo/grantAgreement/EC/H2020::ERC::ERC-STG/715051/EU/Fundamental Physics Using Black Widow, Redback and Transitional Pulsar Binaries/Spiders | en |
dc.rights | © 2023, the Authors. Published by Oxford University Press on behalf of Royal Astronomical Society. | en |
dc.subject | Accretion | en |
dc.subject | Accretion discs | en |
dc.subject | Stars: neutron | en |
dc.subject | X-rays: binaries | en |
dc.subject | X-rays: individual: Swift J1858.6−0814 | en |
dc.title | A rapid optical and X-ray timing study of the neutron star X-ray binary Swift J1858.6−0814 | en |
dc.type | Article (peer-reviewed) | en |
oaire.citation.issue | 1 | en |
oaire.citation.volume | 520 | en |