The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar

© 2020. The American Astronomical Society. All rights reserved.. We report new simultaneous X-ray and radio continuum observations of 3FGL J0427.9-6704, a candidate member of the enigmatic class of transitional millisecond pulsars. These XMM-Newton and Australia Telescope Compact Array observations...

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Main Authors: Li, K.L., Strader, J., Miller-Jones, James, Heinke, C.O., Chomiuk, L.
Format: Journal Article
Language:English
Published: IOP PUBLISHING LTD 2020
Subjects:
Online Access:http://purl.org/au-research/grants/arc/FT140101082
http://hdl.handle.net/20.500.11937/80103
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author Li, K.L.
Strader, J.
Miller-Jones, James
Heinke, C.O.
Chomiuk, L.
author_facet Li, K.L.
Strader, J.
Miller-Jones, James
Heinke, C.O.
Chomiuk, L.
author_sort Li, K.L.
building Curtin Institutional Repository
collection Online Access
description © 2020. The American Astronomical Society. All rights reserved.. We report new simultaneous X-ray and radio continuum observations of 3FGL J0427.9-6704, a candidate member of the enigmatic class of transitional millisecond pulsars. These XMM-Newton and Australia Telescope Compact Array observations of this nearly edge-on, eclipsing low-mass X-ray binary were taken in the sub-luminous disk state at an X-ray luminosity of erg s-1. Unlike the few well-studied transitional millisecond pulsars, which spend most of their disk state in a characteristic high or low accretion mode with occasional flares, 3FGL J0427.9-6704 stayed in the flare mode for the entire X-ray observation of ∼20 hr, with the brightest flares reaching ∼2 × 1034 erg s-1. The source continuously exhibited flaring activity on timescales of ∼10-100 s in both the X-ray and optical/ultraviolet (UV). No measurable time delay between the X-ray and optical/UV flares is observed, but the optical/UV flares last longer, and the relative amplitudes of the X-ray and optical/UV flares show a large scatter. The X-ray spectrum can be well-fit with a partially absorbed power law (Γ ∼ 1.4-1.5), perhaps due to the edge-on viewing angle. Modestly variable radio continuum emission is present at all epochs, and is not eclipsed by the secondary, consistent with the presence of a steady radio outflow or jet. The simultaneous radio/X-ray luminosity ratio of 3FGL J0427.9-6704 is higher than any known transitional millisecond pulsars and comparable to that of stellar-mass black holes of the same X-ray luminosity, providing additional evidence that some neutron stars can be as radio-loud as black holes.
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spelling curtin-20.500.11937-801032020-07-29T07:12:21Z The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar Li, K.L. Strader, J. Miller-Jones, James Heinke, C.O. Chomiuk, L. Science & Technology Physical Sciences Astronomy & Astrophysics Low-mass x-ray binary stars High energy astrophysics Binary pulsars X-RAY BINARIES NEUTRON-STAR 1ST J102347.6+003841 PSR J1023+0038 PULSATIONS PROPELLER EMISSION POWER DISK © 2020. The American Astronomical Society. All rights reserved.. We report new simultaneous X-ray and radio continuum observations of 3FGL J0427.9-6704, a candidate member of the enigmatic class of transitional millisecond pulsars. These XMM-Newton and Australia Telescope Compact Array observations of this nearly edge-on, eclipsing low-mass X-ray binary were taken in the sub-luminous disk state at an X-ray luminosity of erg s-1. Unlike the few well-studied transitional millisecond pulsars, which spend most of their disk state in a characteristic high or low accretion mode with occasional flares, 3FGL J0427.9-6704 stayed in the flare mode for the entire X-ray observation of ∼20 hr, with the brightest flares reaching ∼2 × 1034 erg s-1. The source continuously exhibited flaring activity on timescales of ∼10-100 s in both the X-ray and optical/ultraviolet (UV). No measurable time delay between the X-ray and optical/UV flares is observed, but the optical/UV flares last longer, and the relative amplitudes of the X-ray and optical/UV flares show a large scatter. The X-ray spectrum can be well-fit with a partially absorbed power law (Γ ∼ 1.4-1.5), perhaps due to the edge-on viewing angle. Modestly variable radio continuum emission is present at all epochs, and is not eclipsed by the secondary, consistent with the presence of a steady radio outflow or jet. The simultaneous radio/X-ray luminosity ratio of 3FGL J0427.9-6704 is higher than any known transitional millisecond pulsars and comparable to that of stellar-mass black holes of the same X-ray luminosity, providing additional evidence that some neutron stars can be as radio-loud as black holes. 2020 Journal Article http://hdl.handle.net/20.500.11937/80103 10.3847/1538-4357/ab8f28 English http://purl.org/au-research/grants/arc/FT140101082 IOP PUBLISHING LTD fulltext
spellingShingle Science & Technology
Physical Sciences
Astronomy & Astrophysics
Low-mass x-ray binary stars
High energy astrophysics
Binary pulsars
X-RAY BINARIES
NEUTRON-STAR
1ST J102347.6+003841
PSR J1023+0038
PULSATIONS
PROPELLER
EMISSION
POWER
DISK
Li, K.L.
Strader, J.
Miller-Jones, James
Heinke, C.O.
Chomiuk, L.
The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar
title The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar
title_full The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar
title_fullStr The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar
title_full_unstemmed The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar
title_short The Flare-dominated Accretion Mode of a Radio-bright Candidate Transitional Millisecond Pulsar
title_sort flare-dominated accretion mode of a radio-bright candidate transitional millisecond pulsar
topic Science & Technology
Physical Sciences
Astronomy & Astrophysics
Low-mass x-ray binary stars
High energy astrophysics
Binary pulsars
X-RAY BINARIES
NEUTRON-STAR
1ST J102347.6+003841
PSR J1023+0038
PULSATIONS
PROPELLER
EMISSION
POWER
DISK
url http://purl.org/au-research/grants/arc/FT140101082
http://hdl.handle.net/20.500.11937/80103