By observing bright and compact astronomical sources while also taking data with the 183 GHz Water Vapour Radiometers, ALMA will be able to measure the ‘empirical’ relationship between fluctuations in the phase of the astronomical signal and the fluctuations of sky brightness around 183 GHz. Simulations of such measurements assuming only thermal noise in the astronomical and WVR receivers are p...

Adaptive optics (AO) in astronomical imaging is a technique to improve the quality of image by compensating aberrations induced by atmospheric turbulence. Digital holographic AO (DHAO) is one attractive option to implement AO scheme because it is capable of directly measuring the phase profile of aberration without complicated calculation or loss of resolution of CCD. Hence, if applicable, DHAO...

A novel technique dubbed self-interference incoherent digital holography (SIDH) is being developed for imaging of natural scenes such as astronomical objects or daylightilluminated outdoor scenes. OCIS codes: (090.1995) Digital holography; (100.6880) Three-dimensional image acquisition; (110.1080) Active or

I propose to use as a window the dark core of an optical vortex to examine a weak background signal hidden in the glare of a bright coherent source. Applications such as the detection of an astronomical object, forward-scattered radiation, and incoherent light are described whereby signal enhancements of at least 7 orders of magnitude may be achieved.

We apply the technique of self-organising maps (Kohonen 1990) to the automated classification of singly periodic astronomical lightcurves. We find that our maps readily distinguish between lightcurve types in both synthetic and real datasets, and that the resulting maps do not depend sensitively on the chosen learning parameters. Automated data analysis techniques are likely to be become increa...

The technique of spectroastrometry (measuring the wavelength dependence of the position of an object) provides a means of studying the spatial structure of astronomical sources on scales much smaller than the seeing disk size or the diiraction limit. Despite successful demonstrations in the past, the method does not seem to be widely known. This paper describes techniques used at the Anglo-Aust...

This paper presents results of applying a machine learning technique, the Support Vector Machine (SVM), to the astronomical problem of matching the Infra-Red Astronomical Satellite (IRAS) and Sloan Digital Sky Survey (SDSS) object catalogues. In this study, the IRAS catalogue has much larger positional uncertainties than those of the SDSS. A model was constructed by applying the supervised lear...

We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors. Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean...

We describe a technique for measuring the surface profile of a radio telescope with a fast paraboloidal primary. The technique uses a sensor, at the center of curvature of the primary, consisting of a millimeter-wave source and an array of receivers to measure the field in the caustic. The sensor is mounted on the telescope enclosure and it moves with the telescope, so the measurements can be u...