Image Details
Sub-torque-balance Upper Limits on Continuous Gravitational Waves from Scorpius X-1
A. G. Abac et al 2026 The Astrophysical Journal Letters 1010 .
Caption: Figure 2.
The search region (black parallelogram) for the present analysis, defined by ﹩{t}_{\,{\rm{asc}}\,}^{{\prime} }﹩ [Equation (10)] and ﹩\tilde{P}﹩ [Equation (11)] ranges given in Table 2, expressed in terms of time of ascension ﹩{t}_{\,{\rm{asc}}\,}^{{\prime} }﹩ and orbital period Porb. For comparison, the colored ellipses show the (correlated) uncertainties associated with the PEGS IV ephemeris (T. L. Killestein et al. 2023), corresponding to 1σ, 2σ, and 3σ (containing 39.3%, 86.5%, and 98.9% of the prior probability, respectively). The dashed boundaries show the truncated elliptical search region of the O3 cross-correlation analysis in J. T. Whelan et al. (2023), which also used the PEGS IV ephemeris. Note the dashed diagonal boundaries, which are not vertical, because the ﹩{t}_{\,{\rm{asc}}\,}^{{\prime} }﹩ definition used to specify them was appropriate for the middle of the O3 run (2019) rather than the O4a run (2023).
© 2026. The Author(s). Published by the American Astronomical Society.