The University of Southampton
University of Southampton Institutional Repository

A multi-wavelength view of the outflowing short-period X-ray binary UW CrB

A multi-wavelength view of the outflowing short-period X-ray binary UW CrB
A multi-wavelength view of the outflowing short-period X-ray binary UW CrB
Previous work detected transient ultraviolet outflow features for the short-period (Porb ≈ 111 min), low-mass X-ray binary (LMXB) UW CrB, suggesting the presence of a disc wind in the system. However, because of the transient nature of the outflow features, and the limited amount of data available, the features were challenging to interpret. To follow up on this work, we present a comprehensive multi-wavelength campaign on UW CrB. We observe complex phenomenology and find several features that could be naturally interpreted as being associated with a persistent disc wind. Moreover, we identify a blue-shifted absorption in the Hβ line during one of the epochs, which might be the signature of such an outflow. We present an X-ray to radio campaign of the source, discuss our results in the context of accretion disc wind outflows, present a ‘toy model’ interpretation of the outflow scattering the X-ray emission into our line of sight, and explore the implications for binary evolution models. If correct, our preferred scenario of a persistent disc wind suggests that mass transfer for LMXBs can be non-conservative down to short orbital periods, and thereby opens an important parameter space for angular momentum loss in compact binaries.
X-rays: binaries, accretion, accretion discs, binaries: eclipsing, stars: neutron, stars: winds, outflows
0035-8711
4702-4721
Fijma, S
f27ef41e-8386-4dd5-9665-455044965a0a
Degenaar, N
10239192-96a7-4853-8c66-9dba7bed8785
Segura, N Castro
00cc80f0-a5a7-4002-8f9f-b94e83473718
Maccarone, T J
09732881-0e99-496f-965b-47fc76220466
Knigge, C
ac320eec-631a-426e-b2db-717c8bf7857e
Padilla, M Armas
c8f40acb-97d5-444a-a03f-e9cb40dbbde2
Sánchez, D Mata
2a767b25-5e3c-4c9e-8425-5b3b48ca958c
Muñoz-Darias, T
89a305ff-da1e-42c6-8391-11f9a7703eaf
Santisteban, J V Hernández
8b2354fe-e5e1-4b89-b6bb-a7bb79393c84
Rhodes, L
782beafe-a26a-49e7-bc1c-107a3018f5f0
Bright, J
e9299822-4db6-4b7b-ab82-8178e067cd5f
van den Eijnden, J
d7607cc5-9e91-45fb-927e-f00e3a8018ad
Green, D A
74bb420d-e3b7-44ac-9974-594b853ee742
Fijma, S
f27ef41e-8386-4dd5-9665-455044965a0a
Degenaar, N
10239192-96a7-4853-8c66-9dba7bed8785
Segura, N Castro
00cc80f0-a5a7-4002-8f9f-b94e83473718
Maccarone, T J
09732881-0e99-496f-965b-47fc76220466
Knigge, C
ac320eec-631a-426e-b2db-717c8bf7857e
Padilla, M Armas
c8f40acb-97d5-444a-a03f-e9cb40dbbde2
Sánchez, D Mata
2a767b25-5e3c-4c9e-8425-5b3b48ca958c
Muñoz-Darias, T
89a305ff-da1e-42c6-8391-11f9a7703eaf
Santisteban, J V Hernández
8b2354fe-e5e1-4b89-b6bb-a7bb79393c84
Rhodes, L
782beafe-a26a-49e7-bc1c-107a3018f5f0
Bright, J
e9299822-4db6-4b7b-ab82-8178e067cd5f
van den Eijnden, J
d7607cc5-9e91-45fb-927e-f00e3a8018ad
Green, D A
74bb420d-e3b7-44ac-9974-594b853ee742

Fijma, S, Degenaar, N, Segura, N Castro, Maccarone, T J, Knigge, C, Padilla, M Armas, Sánchez, D Mata, Muñoz-Darias, T, Santisteban, J V Hernández, Rhodes, L, Bright, J, van den Eijnden, J and Green, D A (2025) A multi-wavelength view of the outflowing short-period X-ray binary UW CrB. Monthly Notices of the Royal Astronomical Society, 544 (4), 4702-4721. (doi:10.1093/mnras/staf1790).

Record type: Article

Abstract

Previous work detected transient ultraviolet outflow features for the short-period (Porb ≈ 111 min), low-mass X-ray binary (LMXB) UW CrB, suggesting the presence of a disc wind in the system. However, because of the transient nature of the outflow features, and the limited amount of data available, the features were challenging to interpret. To follow up on this work, we present a comprehensive multi-wavelength campaign on UW CrB. We observe complex phenomenology and find several features that could be naturally interpreted as being associated with a persistent disc wind. Moreover, we identify a blue-shifted absorption in the Hβ line during one of the epochs, which might be the signature of such an outflow. We present an X-ray to radio campaign of the source, discuss our results in the context of accretion disc wind outflows, present a ‘toy model’ interpretation of the outflow scattering the X-ray emission into our line of sight, and explore the implications for binary evolution models. If correct, our preferred scenario of a persistent disc wind suggests that mass transfer for LMXBs can be non-conservative down to short orbital periods, and thereby opens an important parameter space for angular momentum loss in compact binaries.

Text
staf1790 - Version of Record
Available under License Creative Commons Attribution.
Download (4MB)

More information

Accepted/In Press date: 9 August 2025
Published date: 21 October 2025
Additional Information: Publisher Copyright: © The Author(s) 2025. Published by Oxford University Press on behalf of Royal Astronomical Society.
Keywords: X-rays: binaries, accretion, accretion discs, binaries: eclipsing, stars: neutron, stars: winds, outflows

Identifiers

Local EPrints ID: 508014
URI: http://eprints.soton.ac.uk/id/eprint/508014
ISSN: 0035-8711
PURE UUID: 23605cba-d90d-4766-9f35-db61703fc91e

Catalogue record

Date deposited: 09 Jan 2026 17:46
Last modified: 09 Jan 2026 17:47

Export record

Altmetrics

Contributors

Author: S Fijma
Author: N Degenaar
Author: N Castro Segura
Author: T J Maccarone
Author: C Knigge
Author: M Armas Padilla
Author: D Mata Sánchez
Author: T Muñoz-Darias
Author: J V Hernández Santisteban
Author: L Rhodes
Author: J Bright
Author: J van den Eijnden
Author: D A Green

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.

×