相关论文: Two Optical Counterpart Candidates of M82-X1 from …

We present the results of a search for optical identifications of ultraluminous X-ray sources (ULXs) in M51 by using mosaic images taken with the Hubble Space Telescope Advanced Camera for Surveys in filters F435W (B), F555W (V), F814W (I),…

We present a systematic analysis of archival HST WFPC2 ``Association'' data sets that correlate with the Chandra positions of a set of 44 ultra-luminous X-ray sources (ULXs) of nearby galaxies. We have improved the Chandra-HST relative…

We present a photometric survey of the optical counterparts of ultraluminous X-ray sources (ULXs) observed with the Hubble Space Telescope in nearby (< 5 Mpc) galaxies. Of the 33 ULXs with Hubble & Chandra data, 9 have no visible…

In this study, we use archival data from HST, Chandra, XMM-Newton, and Swift-XRT, to probe the nature of 9 (X1-X9) candidate ULXs in NGC 1672. Our study focuses on using the precise source positions obtained via improved astrometry based on…

We report the results of new Hubble Space Telescope imaging of the positions of six ultraluminous X-ray sources (ULXs). Using images in three ACS filters we detect good candidate counterparts to four out of six ULXs, with one more possible…

We present the results of a search for optical counterparts of ultraluminous X-ray source (ULX) X-1 in the nearby galaxy NGC 2500 by using archival images taken with the Hubble Space Telescope ({\it HST}) Wide Field Camera (WFC3)/UVIS. Four…

Archival {\it XMM-Newton}, {\it Chandra} and {\it Hubble Space Telescope (HST)} data have been used to study the X-ray and optical properties of two candidate ultraluminous X-ray sources (ULXs) in NGC\,4536. In order to search for potential…

We present optical identification and characterization of counterparts of four objects previously catalogued as ultra-luminous X-ray sources. The objects were selected from the Colbert & Ptak (2002) catalogue. The optical counterparts are…

In this work, we deploy archival data from {\it HST}, {\it Chandra}, {\it XMM-Newton}, and {\it Swift-XRT}, to probe the nature of 9 candidate ULXs in NGC 1672. Specifically, our study focuses on using the precise source positions obtained…

Using archival Hubble Space Telescope (HST) imaging data, we report the multiband photometric properties of 13 ultraluminous X-ray sources (ULXs) that have a unique compact optical counterpart. Both magnitude and color variation are…

We report the identification of the possible optical counterparts of five out of seven Ultraluminous X-ray Sources (ULXs) in NGC 4490/4485 galaxy pair. Using archival Hubble Space Telescope ({\it HST}) imaging data, we identified a single…

We report on our search for the optical counterparts of two ultraluminous X-ray pulsars with known orbital periods, M82 X-2 and NGC 5907 X-1, in new and archival HST observations, in an effort to characterize the donor stars in these…

We present Chandra and HST observations of the ultraluminous X-ray source (ULX) IC 342 X-1. The Chandra and HST images are aligned using two X-ray emitting foreground stars. The astrometry corrected position for X-1 is R.A. = 03h45m55.61s,…

We present a crossmatch between a combined catalog of X-ray sources and the Vera C. Rubin Observatory Data Preview 1 (DP1) to identify optical counterparts. The six fields targeted as part of DP1 include the Extended Chandra Deep Field…

We present the results of our search for optical counterparts to high-mass X-ray transient sources discovered by various X-ray missions. We obtained CCD images of the X-ray fields through BVR and Halpha filters in order to identify…

We present the results of our continued systematic search for near-infrared (NIR) candidate counterparts to ultraluminous X-ray sources (ULXs) within 10 Mpc. We observed 42 ULXs in 24 nearby galaxies and detected NIR candidate counterparts…

Holmberg IX X-1 is an archetypal ultraluminous X-ray source (ULX). Here we study the properties of the optical counterpart and of its stellar environment using optical data from SUBARU/Faint Object Camera and Spectrograph,GEMINI/GMOS-N and…

Ultra-luminous X-Ray sources are extra-nuclear point sources in external galaxies with $L_X=10^{39}$--$10^{41}$ erg/s and are among the most poorly understood X-ray sources. To help understand their nature, we are trying to identify their…

Ultraluminous X-Ray Objects are off-nucleus point sources with $L_X=10^{39}$-$10^{41}$ erg/s and are among the most poorly understood X-ray sources. To help understand their nature, we are trying to identify their optical counterparts by…

Multiwavelength observations may help us understand the physical nature of the ultraluminous X-ray sources (ULXs) found in external galaxies. Enabled by the arcsecond X-ray source positions now available from Chandra, there has been…