16 citations · 27 across the 6 of their papers we have counts for
9 papers · 1 filter
Multiwavelength Observations and State Transitions of an Ultra-luminous Supersoft X-ray Source: Evidence for an Intermediate-Mass Black Hole
A. K. H. Kong, M. P. Rupen, L. O. Sjouwerman +1
We report the results of Chandra and XMM-Newton observations of an ultra-luminous supersoft X-ray source in M101. M101 ULX-1 underwent 2 outbursts in 2004 during which the peak bol…
A New Kind of Nova
J. L. Sokoloski, S. J. Kenyon, A. K. H. Kong +10
We performed extensive, multi-wavelength observations of the prototypical symbiotic star Z Andromedae between 2000 and 2003, during a large eruption. The rise to optical maximum oc…
Quasisoft X-Ray Sources: Unusual States of Stellar-Mass Objects, or Intermediate Mass Black Holes?
R. Di Stefano, F. A. Primini, A. K. H. Kong +1
Chandra observations of nearby galaxies have revealed a number of X-ray sources characterized by high luminosities ( erg s) and in the range $100 -…
Supersoft and Quasisoft X-Ray Sources in the Globular Clusters of NGC 4472: Are they candidates for intermediate-mass black holes?
R. Di Stefano, R. Friedman, A. Kundu +1
We report on possible associations between 6 globular clusters in the Virgo elliptical galaxy NGC 4472 (M49) and bright ( erg s) very soft X-ray sources (VSSs…
Selecting Very Soft X-Ray Sources in External Galaxies: Luminous Supersoft X-ray Sources and Quasisoft Sources
R. Di Stefano, A. K. H. Kong
We introduce a procedure to identify very soft X-ray sources (VSSs) in external galaxies. Our immediate goal was to formulate a systematic procedure to identify luminous supersoft…
A search for the optical and near-infrared counterpart of the accreting millisecond X-ray pulsar XTE J1751-305
P. G. Jonker, G. Nelemans, Z. Wang +14
We have obtained optical and near-infrared images of the field of the accreting millisecond X-ray pulsar XTE J1751-305. There are no stars in the 0.7'' error circle (0.7'' is the o…