Ultraluminous X-ray sources in seven edge-on spiral galaxies

Kristen C. Dage, Noah Vowell, Erica Thygesen, Arash Bahramian, Daryl Haggard, Konstantinos Kovlakas, Arunav Kundu, Thomas J. Maccarone, Jay Strader, Ryan Urquhart, Stephen E. Zepf

Research output: Contribution to journalArticlepeer-review

2 Scopus citations


We investigate a sample of seven edge-on spiral galaxies using Chandra observations. Edge-on spiral galaxies allow us to clearly separate source associated with their star-forming regions versus the outer edges of the system, offering a clear advantage over other systems. We uncover a number of X-ray point sources across these galaxies, and after eliminating contaminating foreground and background sources, we identify 12 candidate ultraluminous X-ray sources (ULXs). All of these sources are projected on to the central regions, implying that the majority of ULXs in this sample of spiral galaxies are disc/bulge, and thus not halo sources. This also includes two transient ULXs, which may be long-duration transients and low-mass X-ray binaries. This finding illustrates the need for further studies of transient ULXs.

Original languageEnglish
Pages (from-to)4008-4016
Number of pages9
JournalMonthly Notices of the Royal Astronomical Society
Issue number3
StatePublished - Dec 1 2021


  • X-rays: binaries
  • accretion, accretion discs
  • galaxies: spiral


Dive into the research topics of 'Ultraluminous X-ray sources in seven edge-on spiral galaxies'. Together they form a unique fingerprint.

Cite this