This article proposes a class of ultra-wideband 3-D microwave absorbers with composite slotlines and microstrip lines from synthetic design to practical implementation. Firstly, the general equivalent transmission line (TL) model proposed absorber element is formed based on two sets shunt short-ended stubs an i-section nonuniform connecting line. Then, procedure theoretically investigated using...

We use the first data release of the 2-degree Field Quasar survey to investigate the effect of gravitational magnification by foreground absorbing systems on background quasars. We select two populations of quasars from this sample: one with strong Mg II/Fe II absorbers and one without. The selection is done in such a way that the two populations have the same redshift distribution and the abso...

We present a multiwaveband spectroscopic study of the nearby Seyfert 1 galaxy MCG−6-30-15. New optical spectra from the Anglo-Australian Telescope are presented which clearly show the effects of dust extinction/reddening on both the emission line spectrum and the non-stellar AGN continuum. The reddening is constrained to be in the range E(B−V ) = 0.61−1.09. Spectroscopy in the X-ray band, with ...

Deep, 17.8 hours, narrow band imaging obtained at the ESO 3.5m New Technology Telescope has revealed extended (galaxy sized) Ly emission from a high redshift Lyman limit absorber. The absorber is a zabs zem Lyman limit absorber seen in the spectrum of Q1205-30 at zem=3.036. The Ly luminosity of the emission line object is 12–14 1041 h 2 erg s 1 for m=1. The size and morphology of the Ly emitter...

We have built surface micromachined thin-fllm metallized Si_tN-y optical absorbers for transition-edge sensors (TESs) suitable for the Background-Limited far-IR/Submm Spectrograph (BLISS). BLISS is a broadband (38 ;Um-433 jxm ), grating spectrometer consisting of five wavebands each with a modest resolution of R -̂ 1000. Because BLISS requires the effective noise equivalent power (NEP) of the TE...

In this paper, an incident angle- and polarization-insensitive metamaterial absorber is proposed for X-band applications. A unit cell of the proposed absorber has a square patch at the centre and four circular sectors are rotated around the square patch. The vertically and horizontally symmetric structure of the unit cell enables polarization-insensitivity. The circular sector of the unit cell ...