We present an analysis of a Chandra observation of the field surrounding the low-mass X-ray binary 4U 1755−33, which has been in quiescence since 1996. In 2003, Angelini & White reported the appearance of a narrow 7 long jetlike feature centered on the position of 4U 1755−33 using the XMM-Newton telescope. Though the source and jet are not visibly apparent in our Chandra ACIS-S image, there is ...

The accuracy in the photometry of a point source depends on the point-spread function (PSF), detector pixelization, and observing strategy. The PSF and pixel response describe the spatial blurring of the source, the pixel scale describes the spatial sampling of a single exposure, and the observing strategy determines the set of dithered exposures with pointing offsets from which the source flux...

We consider the inverse problem of discovering the location of a source from very sparse point measurements in a bounded domain that contains impenetrable (and possibly unknown) obstacles. We present an adaptive algorithm for determining the measurement locations, and ultimately, the source locations. Specifically, we investigate source discovery for the Laplace operator, though the approach ca...

We extend the phase modulation method by in-plane diffractions from plane wave incidence to point source of surface plasmon polariton (SPP). A well-defined SPP focus is successfully realized from a point source under the diffraction by a carefully designed nanohole array, which is easy to layout in the future integrated optical circuits. With this method, the SPP Airy beam and finite plane wave...