The University of Southampton
University of Southampton Institutional Repository

A NICER thermonuclear burst from the millisecond X-Ray pulsar SAX J1808.4-3658

A NICER thermonuclear burst from the millisecond X-Ray pulsar SAX J1808.4-3658
A NICER thermonuclear burst from the millisecond X-Ray pulsar SAX J1808.4-3658
The Neutron Star Interior Composition Explorer (NICER) has extensively monitored the 2019 August outburst of the 401 Hz millisecond X-ray pulsar SAX J1808.4–3658. In this Letter, we report on the detection of a bright helium-fueled Type I X-ray burst. With a bolometric peak flux of (2.3 ± 0.1) × 10−7 erg s−1 cm−2, this was the brightest X-ray burst among all bursting sources observed with NICER to date. The burst shows a remarkable two-stage evolution in flux, emission lines at 1.0 and 6.7 keV, and burst oscillations at the known pulsar spin frequency, with ≈4% fractional sinusoidal amplitude. We interpret the burst flux evolution as the detection of the local Eddington limits associated with the hydrogen and helium layers of the neutron star envelope. The emission lines are likely associated with Fe, due to reprocessing of the burst emission in the accretion disk.
2041-8205
Bult, Peter
73bd0a3d-c566-4046-86c9-31f6e6cdac07
Jaisawal, Gaurava K.
73d1fabe-7543-4658-af93-3bb2e9557c7d
Guver, Tolga
5fdfca08-f31f-4aff-8802-9f6e1948b545
Strohmayer, Tod E.
09bbe020-7c6f-496b-a058-51385cf48f85
Altamirano, Diego
d5ccdb09-0b71-4303-9538-05b467be075b
Arzoumanian, Zaven
5befbba6-f6a1-47c8-ae9e-021c5d854a64
Ballantyne, David R.
2e090d45-4bf6-480e-a634-6f9eb5a511b7
Chakrabarty, Deepto
322198a5-4c3a-4369-99ee-b66befa6a518
Chenevez, Jérôme
25a95602-9e3d-4553-a442-5f4317ff2cd6
Gendreau, Keith C.
cad26609-b22d-4c1d-ada3-4af51e2cd780
Guillot, Sebastien
26b90302-d8b3-4b06-9254-d3327cac3ccc
Ludlam, Renee M.
b27b6ff8-9743-49f2-833a-115803efa43a
Bult, Peter
73bd0a3d-c566-4046-86c9-31f6e6cdac07
Jaisawal, Gaurava K.
73d1fabe-7543-4658-af93-3bb2e9557c7d
Guver, Tolga
5fdfca08-f31f-4aff-8802-9f6e1948b545
Strohmayer, Tod E.
09bbe020-7c6f-496b-a058-51385cf48f85
Altamirano, Diego
d5ccdb09-0b71-4303-9538-05b467be075b
Arzoumanian, Zaven
5befbba6-f6a1-47c8-ae9e-021c5d854a64
Ballantyne, David R.
2e090d45-4bf6-480e-a634-6f9eb5a511b7
Chakrabarty, Deepto
322198a5-4c3a-4369-99ee-b66befa6a518
Chenevez, Jérôme
25a95602-9e3d-4553-a442-5f4317ff2cd6
Gendreau, Keith C.
cad26609-b22d-4c1d-ada3-4af51e2cd780
Guillot, Sebastien
26b90302-d8b3-4b06-9254-d3327cac3ccc
Ludlam, Renee M.
b27b6ff8-9743-49f2-833a-115803efa43a

Bult, Peter, Jaisawal, Gaurava K., Guver, Tolga, Strohmayer, Tod E., Altamirano, Diego, Arzoumanian, Zaven, Ballantyne, David R., Chakrabarty, Deepto, Chenevez, Jérôme, Gendreau, Keith C., Guillot, Sebastien and Ludlam, Renee M. (2019) A NICER thermonuclear burst from the millisecond X-Ray pulsar SAX J1808.4-3658. The Astrophysical Journal Letters, 855 (1), [L1]. (doi:10.3847/2041-8213/ab4ae1).

Record type: Article

Abstract

The Neutron Star Interior Composition Explorer (NICER) has extensively monitored the 2019 August outburst of the 401 Hz millisecond X-ray pulsar SAX J1808.4–3658. In this Letter, we report on the detection of a bright helium-fueled Type I X-ray burst. With a bolometric peak flux of (2.3 ± 0.1) × 10−7 erg s−1 cm−2, this was the brightest X-ray burst among all bursting sources observed with NICER to date. The burst shows a remarkable two-stage evolution in flux, emission lines at 1.0 and 6.7 keV, and burst oscillations at the known pulsar spin frequency, with ≈4% fractional sinusoidal amplitude. We interpret the burst flux evolution as the detection of the local Eddington limits associated with the hydrogen and helium layers of the neutron star envelope. The emission lines are likely associated with Fe, due to reprocessing of the burst emission in the accretion disk.

Text
A NICER Thermonuclear Burst from the Millisecond X-Ray Pulsar SAX J1808.4-3658 - Accepted Manuscript
Download (556kB)

More information

Accepted/In Press date: 4 October 2019
e-pub ahead of print date: 23 October 2019
Additional Information: arxiv is am

Identifiers

Local EPrints ID: 437002
URI: http://eprints.soton.ac.uk/id/eprint/437002
ISSN: 2041-8205
PURE UUID: 46e23720-e7b4-423f-9567-be21136d8120
ORCID for Diego Altamirano: ORCID iD orcid.org/0000-0002-3422-0074

Catalogue record

Date deposited: 15 Jan 2020 17:30
Last modified: 17 Mar 2024 03:34

Export record

Altmetrics

Contributors

Author: Peter Bult
Author: Gaurava K. Jaisawal
Author: Tolga Guver
Author: Tod E. Strohmayer
Author: Zaven Arzoumanian
Author: David R. Ballantyne
Author: Deepto Chakrabarty
Author: Jérôme Chenevez
Author: Keith C. Gendreau
Author: Sebastien Guillot
Author: Renee M. Ludlam

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.

×