The ROSAT Deep Survey IV. A distant lensing cluster of galaxies with a bright arc

G. Hasinger, R. Giacconi, J. E. Gunn, I. Lehmann, M. Schmidt, D. P. Schneider, J. Trümper, J. Wambsganss, D. Woods, G. Zamorani

Research output: Contribution to journalReview articlepeer-review

30 Scopus citations


An unusual double-lobed extended X-ray source (RX J105343+5735) is detected in the ROSAT ultra-deep HRI image of the Lockman Hole. The angular size of the source is 1.7 × 0.7 arcmin2 and its X-ray flux is 2 × 10-14 erg cm-2 s-1. R-band imaging from the Keck telescope revealed a marginal excess of galaxies brighter than R=24.5, but Keck LRIS spectroscopy of 24 objects around the X-ray centroid did not yield a significant number of concordant redshifts. The brightest galaxy close to the centre of the eastern emission peak appears to be a gravitationally lensed arc at z=2.570, suggesting that the X-ray object is associated with the lens, most likely a cluster of galaxies. Based on a comparison of lensing surface mass density, X-ray luminosity, morphology and galaxy magnitudes with clusters of known distance, we argue that RX J105343+5735 is a cluster at a redshift around 1. Future X-ray, ground-based optical/NIR and high resolution HST observations of the system will be able to clarify the nature of the object.

Original languageEnglish (US)
Pages (from-to)L27-L30
JournalAstronomy and Astrophysics
Issue number2
StatePublished - 1998

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'The ROSAT Deep Survey IV. A distant lensing cluster of galaxies with a bright arc'. Together they form a unique fingerprint.

Cite this