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A time-variable scattered component to broad Hα in the Seyfert 1 galaxy Mrk 509
(1999)
We present optical spectropolarimetry data for the Seyfert 1 galaxy Mrk 509 for three epochs: 1996 August and 1997 May and August. We confirm previous findings that broad Hα has a significantly greater width in the polarized ...
Polarized broad HeI and Paschen lines in NGC 1068
(1999)
We present J-band spectropolarimetry of NGC 1068. We observe polarized broad Pa β and, for the first time, polarized broad Pa γ and HeI. Assuming electron scattering as the polarization mechanism, the polarized broad lines ...
Searching for the hidden broad-line region in Centaurus A
(1999)
We present the first near-infrared (K-band) spectropolarimetric observations of the nuclear region of Centaurus A. Although the data are of high signal-to-noise ratio, polarized broad Brγ is not detected and we place a 3σ ...
The magnetic field structure of the DR21 region
(1999)
We present results of imaging polarimetry of the H2 v=1--0 S(1) line towards the outflow lobes of DR21. The polarization vectors are produced by dichroic absorption in a medium of aligned grains and therefore delineate the ...
Optical Spectropolarimetry of Broad Line Active Galaxies
(Astronomical Society of the Pacific, 1999)
We present new optical spectropolarimetry of two bright type 1 AGNs. The observations are part of a project on broad line active galaxies in which, through data analysis and modelling, we aim to identify the polarization ...
Monitoring the Ha Line in BL Lacertae - Evidence for an Accretion Disk
(Astronomical Society of the Pacific, 1999)
We present new spectroscopic observations of the recently discovered broad Ha line in BL Lacertae. These data, obtained over a period of 30 months, indicate that the line equivalent width is anti-correlated with the continuum ...
Observations and a model for the infrared continuum of Centaurus A
(1999)
We present ISOPHOT S, ISOSWS and 8 to 13 mi- cron ground based observations of Centaurus A that show prominent PAH and silicate features. These and other data are used to construct a model for the infrared continuum. We ...
A Seyfert Nucleus in BL Lacertae
(Astronomical Society of the Pacific, 1999)
We have obtained spectroscopic observations of the broad Ha line in BL Lacertae over a period of 30 months. These data show that the line equivalent width is anti-correlated with the continuum flux implying that the broad ...
Polarimetry for the Gemini telescopes
(1998)
Polarimeters at optical and near-IR wavelengths are increasingly available as part of facility instruments at major observatories, and are used for a large number of astronomical programs, ranging form nearby star-forming ...
Circular Polarization in Star- Formation Regions : Implications for Biomolecular Homochirality
(1998)
Strong infrared circular polarization resulting from dust scattering in reflection nebulae in the Orion OMC-1 star-formation region has been observed. Circular polarization at shorter wavelengths might have been important ...