English

Continuous gravitational waves from magnetized white dwarfs: Quantifying the detection plausibility by LISA

High Energy Astrophysical Phenomena 2025-10-29 v1 Solar and Stellar Astrophysics

Abstract

White dwarfs (WDs) are frequently observed to have strong magnetic fields up to 10910^9 G and expected to have a possible internal field as high as 1014\sim 10^{14} G. High internal fields can significantly deform a WD's equilibrium structure, generating a quadrupole moment. If the rotation axis is misaligned with the magnetic axis, the deformation can lead to the emission of continuous gravitational waves (CGWs). We examine the potential for detecting CGWs from magnetized WDs with future space-based detectors such as LISA, ALIA, DECIGO, Deci-Hz, BBO and TianQin. We model the field-induced deformation and compute the resulting GW strain, incorporating amplitude decay due to angular momentum loss from electromagnetic and gravitational radiation. This sets a timescale for detection -`active timescale' of 105610^{5-6} yr, requiring observation while the object remains sufficiently young. Our results suggest that LISA could detect a few dozens of highly magnetized WDs across the Galaxy during its mission. As a specific case, we investigate ZTF J1901+1458- a compact, massive, fast-rotating, and strongly magnetized WD with spin period 416\sim416 s and inferred surface field 109\sim10^{9} G. We find that this object would be detectable by LISA with four years of continuous data. This highlights the potential of CGW observations to probe magnetic field structure in WDs and their role in type Ia supernova progenitors.

Keywords

Cite

@article{arxiv.2510.23724,
  title  = {Continuous gravitational waves from magnetized white dwarfs: Quantifying the detection plausibility by LISA},
  author = {Mayusree Das and Banibrata Mukhopadhyay and Tomasz Bulik},
  journal= {arXiv preprint arXiv:2510.23724},
  year   = {2025}
}

Comments

16 pages including 14 figures and 1 table; accepted for publication in The Astrophysical Journal

R2 v1 2026-07-01T07:08:19.463Z