MBCAA Observatory


Observed: 3, 5, 16, 17, 20 July, 4, 5 August 2005

Michel Bonnardeau
4 July 2005
Updated: 17 August 2005


Time-series for this X and gamma-ray transient, which may be a black hole candidate, are presented.


SwiftJ1753.5-0127 was detected as a new, bright, variable gamma-ray and X-ray source by the Swift satellite on 29 June 2005 (The Astronomer's Telegram ATel 546, 547, 550). A mag 15 optical counterpart was found on 2 July 2005 (Atel 549). Swift data shows "a 0.6 Hz QPO with a shape typically seen in BH Candidates" (ATel 550).


SwiftJ1753.5-0127 was observed with a 203mm f/6.3 SC telescope, a SBIG ST7E camera (KAF401E CCD) and a Clear filter. 73 images were obtained on 3-4 July 2005 between 22:06 TU and 02:30 TU. Each exposure lasts 200 seconds (except the first one). 5 images were obtained that followed.

The comparison star is UCAC2 31 365 377 with an assumed unfiltered magnitude of 14.000. The check star is UCAC2 31 363 373 with an average measured magnitude of 16.053 (standard deviation 0.094).

An example of an image:

Red ticks: SwiftJ1753.5-0127, Yellow square: the comparison star, Blue ticks: the check star.

The following light curve was obtained:

Red: SwiftJ1753.5-0127, Blue: the check star shifted by +0.2 mag. The error bars are the 1-sigma statistical uncertainties.

The brightness appears to be constant at 15.788 mag, standard deviation 0.074.

More observations found the object to be steady:

Technical notes

Telescope and camera configuration.

Software and computer configuration.

Site map


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