Mirabal, N.2020-09-042020-09-042010-02-02N. Mirabal, A curious source of extended X-ray emission in the outskirts of globular cluster GLIMPSE-C01, Monthly Notices of the Royal Astronomical Society, Volume 402, Issue 2, February 2010, Pages 1391–1396, https://doi.org/10.1111/j.1365-2966.2009.15984.xhttps://doi.org/10.1111/j.1365-2966.2009.15984.xhttp://hdl.handle.net/11603/19590We report the discovery of an unusual source of extended X-ray emission CXOU J184846.3–013040 (‘The Stem’) located on the outskirts of the globular cluster GLIMPSE-C01. No point-like source falls within the extended emission which has an X-ray luminosity LX(0.3–8 keV) ∼ 10³² erg s⁻¹ and a physical size of ∼0.1 pc at the inferred distance to the cluster. These X-ray properties are consistent with the pulsar wind nebula of an unseen pulsar located within the 95 per cent confidence error contour of an unidentified Fermiγ-ray source 0FGL J1848.6–0138. However, we cannot exclude an alternative interpretation that postulates X-ray emission associated with a bow shock produced from the interaction of the globular cluster and interstellar gas in the Galactic plane. Analysis of the X-ray data reveals that ‘The Stem’ is most significant in the 2–5 keV band, which suggests that the emission may be dominated by non-thermal bremsstrahlung from suprathermal electrons at the bow shock. If the bow shock interpretation is correct, these observations would provide compelling evidence that GLIMPSE-C01 is shedding its intracluster gas during a galactic passage. Such a direct detection of gas stripping would help clarify a crucial step in the evolutionary history of globular clusters. Intriguingly, the data may also accommodate a new type of X-ray source.7 pagesen-USThis item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.Text