The extinction curve of the lensing galaxy of B1152+199 at z=0.44

We present UBVRIz' photometry of the gravitational lens candidate CLASS B1152+119 obtained with the Nordic Optical Telescope. The two QSO components are resolved in the B, V, R, I and z' bands confirming the lensing nature of the system. The z=0.44 lens galaxy is clearly detected in B, R, I and z' and its position is found to be almost coincident with the faint QSO image which is heavily extincted (relative to the brighter QSO image) by dust in the lens galaxy. The extinction curve of the lens galaxy derived from the relative photometry is well fitted by a Galactic extinction law with 1.3 < R_V < 2.0 and E(B-V) ~ 1. From a simple model of the system we predict a time delay of ~ 60 days.Comment: 6 pages, 7 figures, accepted for publication in Astronomy and Astrophysic

Hyperspectral Video Analysis by Motion and Intensity Preprocessing and Subspace Autoencoding

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Multitemporal Feature-Level Fusion on Hyperspectral and LiDAR Data in the Urban Environment

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The Effect of Pull Speed and Heat Treatment on Thermal Donors in Czhocralski Silicon

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Integration of Hyperspectral and Magnetic Data for Geological Characterization of the Niaqornarssuit Ultramafic Complex in West-Greenland

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Exploring Robots and UAVs as Phenotyping Tools in Plant Breeding

Recent advances in robot and sensor technology makes it possible to survey a large number of plants in a non destructive and cost efficient way. The present research approach includes measurements with VIS/NIR multi-spectral camera mounted on UAV and robot and traditional manual ground measurements. The analysis presented here, aims (1) to evaluate the use of multi-spectral imaging from drone and robot as phenotyping tools, (2) to compare images from drone and robot to see how they can complement each other for an optimised analysis of the plants and (3) to study the reflectance response of various plant species exposed to two different regimes of fertilisers. The sensors on UAVs provide a unique perspective of the growth of the plants revealing the map of the variations within the field of stud

The time delay of the quadruple quasar RX J0911.4+0551

We present optical lightcurves of the gravitationally lensed components A (=A1+A2+A3) and B of the quadruple quasar RX J0911.4+0551 (z = 2.80). The observations were primarily obtained at the Nordic Optical Telescope between 1997 March and 2001 April and consist of 74 I-band data points for each component. The data allow the measurement of a time delay of 146 +- 8 days (2 sigma) between A and B, with B as the leading component. This value is significantly shorter than that predicted from simple models and indicates a very large external shear. Mass models including the main lens galaxy and the surrounding massive cluster of galaxies at z = 0.77, responsible for the external shear, yield H_0 = 71 +- 4 (random, 2 sigma) +- 8 (systematic) km/s/Mpc. The systematic model uncertainty is governed by the surface-mass density (convergence) at the location of the multiple images.Comment: 12 pages, 3 figures, ApJL, in press (June 20, 2002

Application of unmanned aerial vehicles in earth resources monitoring: Focus on evaluating potentials for forest monitoring in Ethiopia

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