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arXiv · 2608.07662

The G347.3-0.5 outlier from O3: a follow-up case study for continuous gravitational-wave candidates

L. Mirasola·F. Amicucci·M. Carrio·D. H. T. Cheung·M. A. Ferrer-Martinez·E. Goetz·D. Keitel·A. M. Knee·P. Leaci·C. Palomba·K. Pham·O. J. Piccinni·M. Pitkin·I. Prohens·K. Riles·S. Safi-Harb·G. Woan·Z. Zhang·M. Bejger·A. Calafat·R. Jaume·D. I. Jones·A. Krolak·I. La Rosa·A. Melatos·J. R. Mérou·A. Nemmani·B. Rajbhandari·C. Salvadore·A. M. Sintes·R. Tenorio·K. Wette·J. T. Whelan·T. S. Yamamoto
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Abstract

We report a multi-pipeline follow-up study of the continuous gravitational-wave (CW) outlier identified by the Ming et al. Einstein@Home directed search for the young supernova remnant G347.3-0.5 (containing the central compact object RXJ1713.7-3946). The outlier was initially identified in LIGO data from the O3a observing run and followed up with the addition of O3b and O4a data by the Einstein@Home pipeline, with O4a producing weaker evidence. Here, we show extended data quality checks and results from three pipelines that have independently investigated this outlier, including the newly released O4b data set. We can robustly recover the outlier in O3, while we find no evidence for a related standard CW signal in O4a (consistent with Ming et al.) and O4b data. This work serves as a useful test case for future multi-pipeline follow-ups of CW candidates that aim to investigate their astrophysical or noise nature, and it is therefore an important step in preparation for the first CW detection.

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L. Mirasola, F. Amicucci, M. Carrio, D. H. T. Cheung, M. A. Ferrer-Martinez, E. Goetz, D. Keitel, A. M. Knee, P. Leaci, C. Palomba, K. Pham, O. J. Piccinni, M. Pitkin, I. Prohens, K. Riles, S. Safi-Harb, G. Woan, Z. Zhang, M. Bejger, A. Calafat, R. Jaume, D. I. Jones, A. Krolak, I. La Rosa, A. Melatos, J. R. Mérou, A. Nemmani, B. Rajbhandari, C. Salvadore, A. M. Sintes, R. Tenorio, K. Wette, J. T. Whelan, T. S. Yamamoto. 2026-08-07. The G347.3-0.5 outlier from O3: a follow-up case study for continuous gravitational-wave candidates. https://arxiv.org/abs/2608.07662

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