A Unified Mass-Loading Model for ASKAP J1745-5051: Linking Long-Period Radio Transients to Magnetic Cataclysmic Variables
Abstract
Long-period radio transients (LPTs) in white dwarf binaries require sufficiently tenuous plasma to sustain coherent radio emission, posing a challenge in systems with dense accretion flows. ASKAP J1745-5051 (J1745) combines LPT-like radio pulses recurring approximately every 82 min with magnetic accretion and X-ray modulation at a consistent period. We investigate this coexistence using a unified mass-loading framework for Roche-lobe overflow and a tenuous donor wind in the binary magnetic field. The dense stream supplies the accretion curtain and near-white-dwarf X-ray sources, while the tenuous wind feeds flux tubes of (1−4)×107 cm−3, satisfying the local density requirement for electron-cyclotron maser emission. A fiducial geometry places the X-ray maximum near orbital phase $0.886$ and produces a radio-visibility window at phases $0.22-0.33$, consistent with the primary observed pulse window. Geometrical modulation and curtain absorption produce stronger soft-band than hard-band X-ray variability. Long-term phase-connected radio monitoring and simultaneous X-ray observations can test this interpretation through recurring radio phase changes and correlated changes in X-ray modulation. These results extend the proposed connection between detached binary LPTs and magnetic cataclysmic variables (mCVs). J1745 may represent an evolved mCV near the orbital-period minimum, suggesting that LPT-like activity can occur at a late accreting stage.
Related
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BibTeX
@misc{zhan2026unified,
title = {{A Unified Mass-Loading Model for ASKAP J1745-5051: Linking Long-Period Radio Transients to Magnetic Cataclysmic Variables}},
author = {Yejing Zhan and Fa-Yin Wang},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.00581},
eprint = {2611.00581},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.00581},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - A Unified Mass-Loading Model for ASKAP J1745-5051: Linking Long-Period Radio Transients to Magnetic Cataclysmic Variables
AU - Yejing Zhan
AU - Fa-Yin Wang
PY - 2026
DA - 2026/11/01
PB - arXiv
DO - 10.48550/arxiv.2611.00581
UR - https://arxiv.org/abs/2611.00581
AB - Long-period radio transients (LPTs) in white dwarf binaries require sufficiently tenuous plasma to sustain coherent radio emission, posing a challenge in systems with dense accretion flows. ASKAP J1745-5051 (J1745) combines LPT-like radio pulses recurring approximately every 82 min with magnetic accretion and X-ray modulation at a consistent period. We investigate this coexistence using a unified mass-loading framework for Roche-lobe overflow and a tenuous donor wind in the binary magnetic field. The dense stream supplies the accretion curtain and near-white-dwarf X-ray sources, while the tenuous wind feeds flux tubes of (1−4)×10^7 cm^−3, satisfying the local density requirement for electron-cyclotron maser emission. A fiducial geometry places the X-ray maximum near orbital phase $0.886$ and produces a radio-visibility window at phases $0.22-0.33$, consistent with the primary observed pulse window. Geometrical modulation and curtain absorption produce stronger soft-band than hard-band X-ray variability. Long-term phase-connected radio monitoring and simultaneous X-ray observations can test this interpretation through recurring radio phase changes and correlated changes in X-ray modulation. These results extend the proposed connection between detached binary LPTs and magnetic cataclysmic variables (mCVs). J1745 may represent an evolved mCV near the orbital-period minimum, suggesting that LPT-like activity can occur at a late accreting stage.
ER -