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Biosignatures as revealed by spectropolarimetry of Earthshine
Nature, 2012Low-resolution intensity spectra of Earth's atmosphere obtained from space reveal strong signatures of life ('biosignatures'), such as molecular oxygen and methane with abundances far from chemical equilibrium, as well as the presence of a 'red edge' (a sharp increase of albedo for wavelengths longer than 700 nm) caused by surface vegetation.
Michael F, Sterzik +2 more
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Spectropolarimetry with the NLST
2009India’s National Large Solar Telescope (NLST) will provide opportunities to observe the Sun with high spatial, spectral, and polarimetric resolution. The large aperture also enables high-cadence spectropolarimetry with moderate spatial resolution. A multi-slit spectropolarimeter is planned as one of the back-end instruments for this powerful telescope,
K. Sankarasubramanian +2 more
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Robust snapshot interferometric spectropolarimetry
Optics Letters, 2016This Letter describes a Stokes vector measurement method based on a snapshot interferometric common-path spectropolarimeter. The proposed scheme, which employs an interferometric polarization-modulation module, can extract the spectral polarimetric parameters Ψ(k) and Δ(k) of a transmissive anisotropic object by which an accurate Stokes vector can be ...
Daesuk, Kim +6 more
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Invitation to Spectropolarimetry
2004Recent research has made clear the exceptional importance of spectropolarimetry in the study of physical conditions in atmospheres and circumstellar envelopes of different kinds of stars, in galactic nuclei and to obtain knowledge about interstellar matter.
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Spectropolarimetry with a cube beamsplitter
Experimental Astronomy, 1992For less than $2000 in materials we have exploited the DAO 1.8 m Cassegrain spectrograph between 430 and 800 nm for differential linear spectropolarimetry at resolutions up to ∼30,000 by using a beamsplitting cube as single-channel analyser. The position angle of the cube is under microprocessor control and, to counteract the highly erratic response of
Gordon Walker +3 more
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Spectropolarimetry of hot, luminous stars
Astrophysics and Space Science, 1994I review polarimetric observations of presumably single, hot, luminous stars. The stellar types discussed are OB stars, B[e] supergiants, Luminous Blue Variables (LBV), Wolf-Rayet (W-R) stars, and type II supernovae (SN). It is shown that variable, intrinsic polarization is a common phenomenon in that part of the Hertzsprung-Russell (HR) diagram which ...
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Infrared spectropolarimetry of sunspots
Astronomische Nachrichten, 2002Recently a number of works have given interesting results on the penumbral fine structure of sunpots (del Toro Iniesta, Bellot Rubio & Collados 2001; Schlichenmaier & Collados 2002), where, for instance, cold supersonic Evershed downflows were observed.
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Precision laser spectropolarimetry
Journal of Russian Laser Research, 1994A procedure for precision measurements of small angle rotation of light polarization plane vs wavelength is described. Analyzed at length is the optical spectropolarimeter configuration, wherein the frequency-dependent instrumental rotations are suppressed to the maximum degree.
G. N. Birich +6 more
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Subaru spectropolarimetry of supernovae
AIP Conference Proceedings, 2012Spectropolarimetry is one of the most powerful methods to study the multi-dimensional geometry of extragalactic supernovae (SNe). We have performed spectropolarimetric observations of Type Ib/c SNe with the Subaru telescope. The data clearly show the "loop" in the Stokes Q - U plane.
Tanaka, M. +10 more
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