The University of Southampton
University of Southampton Institutional Repository

AstroSat observations of the first Galactic ULX pulsar Swift J0243.6+6124

AstroSat observations of the first Galactic ULX pulsar Swift J0243.6+6124
AstroSat observations of the first Galactic ULX pulsar Swift J0243.6+6124
Swift J0243.6+6124, the first Galactic ultra-luminous X-ray pulsar, was observed during its 2017-2018 outburst with AstroSat at both sub- and super-Eddington levels of accretion with X-ray luminosities of Lx~7x10^37 and 6x10^38 erg/s, respectively. Our broadband timing and spectral observations show that X-ray pulsations at ~9.85 s have been detected up to 150 keV when the source was accreting at the super-Eddington level. The pulse profiles are a strong function of both energy and source luminosity, showing a double-peaked profile with pulse fraction increasing from ~10% at 1.65 keV to 40-80% at 70 keV. The continuum X-ray spectra are well-modeled with a high energy cut-off power law (Gamma~0.6-0.7) and one or two blackbody components with temperatures of ~0.35 keV and 1.2 keV, depending on the accretion level. No iron line emission is observed at sub-Eddington level, while a broad emission feature at around 6.9 keV is observed at the super-Eddington level, along with a blackbody radius (121-142 km) that indicates the presence of optically thick outflows.
0035-8711
565-575
Beri, Aru
69ed346a-f02a-4243-83f9-ad5ab4c4008c
Naik, Sachindra
af278542-177d-47f9-ae51-00babd03e877
Singh, K. P.
9e897c11-9ee3-41c6-b700-6479f597909d
Jaisawal, Gaurava K.
4d5dcd39-0881-426d-8ad7-f378238405ae
Bhattacharyya, Sudip
f7f510c1-331f-4e01-aada-f44c2d3fbf57
Charles, Philip
0429b380-0754-4dc1-8def-885c7fa6a086
Ho, Wynn C. G.
d78d4c52-8f92-4846-876f-e04a8f803a45
Maitra, Chandreyee
68633a6f-c681-4649-b891-7fdbf8d4fb70
Bhattacharya, Depankar
acf23924-0dfb-4646-8901-4f3f9cecbf55
Dewangan, Gulab C.
0062ef4f-8422-4085-a1de-8c72f472843c
Middleton, Matthew
f91b89d9-fd2e-42ec-aa99-1249f08a52ad
Altamirano, Diego
d5ccdb09-0b71-4303-9538-05b467be075b
Gandhi, Poshak
5bc3b5af-42b0-4dd8-8f1f-f74048d4d4a9
Raichur, Harsha
2e12f4b8-121a-4837-a292-449c2da24f6d
Beri, Aru
69ed346a-f02a-4243-83f9-ad5ab4c4008c
Naik, Sachindra
af278542-177d-47f9-ae51-00babd03e877
Singh, K. P.
9e897c11-9ee3-41c6-b700-6479f597909d
Jaisawal, Gaurava K.
4d5dcd39-0881-426d-8ad7-f378238405ae
Bhattacharyya, Sudip
f7f510c1-331f-4e01-aada-f44c2d3fbf57
Charles, Philip
0429b380-0754-4dc1-8def-885c7fa6a086
Ho, Wynn C. G.
d78d4c52-8f92-4846-876f-e04a8f803a45
Maitra, Chandreyee
68633a6f-c681-4649-b891-7fdbf8d4fb70
Bhattacharya, Depankar
acf23924-0dfb-4646-8901-4f3f9cecbf55
Dewangan, Gulab C.
0062ef4f-8422-4085-a1de-8c72f472843c
Middleton, Matthew
f91b89d9-fd2e-42ec-aa99-1249f08a52ad
Altamirano, Diego
d5ccdb09-0b71-4303-9538-05b467be075b
Gandhi, Poshak
5bc3b5af-42b0-4dd8-8f1f-f74048d4d4a9
Raichur, Harsha
2e12f4b8-121a-4837-a292-449c2da24f6d

Beri, Aru, Naik, Sachindra, Singh, K. P., Jaisawal, Gaurava K., Bhattacharyya, Sudip, Charles, Philip, Ho, Wynn C. G., Maitra, Chandreyee, Bhattacharya, Depankar, Dewangan, Gulab C., Middleton, Matthew, Altamirano, Diego, Gandhi, Poshak and Raichur, Harsha (2020) AstroSat observations of the first Galactic ULX pulsar Swift J0243.6+6124. Monthly Notices of the Royal Astronomical Society, 500 (1), 565-575. (doi:10.1093/mnras/staa3254).

Record type: Article

Abstract

Swift J0243.6+6124, the first Galactic ultra-luminous X-ray pulsar, was observed during its 2017-2018 outburst with AstroSat at both sub- and super-Eddington levels of accretion with X-ray luminosities of Lx~7x10^37 and 6x10^38 erg/s, respectively. Our broadband timing and spectral observations show that X-ray pulsations at ~9.85 s have been detected up to 150 keV when the source was accreting at the super-Eddington level. The pulse profiles are a strong function of both energy and source luminosity, showing a double-peaked profile with pulse fraction increasing from ~10% at 1.65 keV to 40-80% at 70 keV. The continuum X-ray spectra are well-modeled with a high energy cut-off power law (Gamma~0.6-0.7) and one or two blackbody components with temperatures of ~0.35 keV and 1.2 keV, depending on the accretion level. No iron line emission is observed at sub-Eddington level, while a broad emission feature at around 6.9 keV is observed at the super-Eddington level, along with a blackbody radius (121-142 km) that indicates the presence of optically thick outflows.

Text
2010.08334 - Accepted Manuscript
Download (791kB)

More information

Accepted/In Press date: 15 October 2020
Published date: 21 October 2020

Identifiers

Local EPrints ID: 444889
URI: http://eprints.soton.ac.uk/id/eprint/444889
ISSN: 0035-8711
PURE UUID: 84b1fb3f-65ff-4308-a8db-7f0d4207a1b3
ORCID for Wynn C. G. Ho: ORCID iD orcid.org/0000-0002-6089-6836
ORCID for Diego Altamirano: ORCID iD orcid.org/0000-0002-3422-0074
ORCID for Poshak Gandhi: ORCID iD orcid.org/0000-0003-3105-2615

Catalogue record

Date deposited: 10 Nov 2020 17:30
Last modified: 18 Feb 2021 17:24

Export record

Altmetrics

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×