71 citations · 587 across the 25 of their papers we have counts for
25 papers
Planet-wide, Concentric Density Waves in Venus's Upper Atmosphere Revealed through Polarimetry?
Gourav Mahapatra, Michiel Rodenhuis, Frans Snik +3
We report observations of faint (), concentric, planet-wide rings in the polarized flux of sunlight that is reflected by Venus, obtained during a serendipitous, 36-minute…
The MICADO first light imager for the ELT: off-axis performance of PSF reconstruction
Matteo Simioni, Daniel Jodlbauer, Carmelo Arcidiacono +14
The highest scientific return, for adaptive optics (AO) observations, is achieved with a reliable reconstruction of the PSF. This is especially true for MICADO@ELT. In this present…
The BlackGEM telescope array I: Overview
Paul J. Groot, S. Bloemen, P. Vreeswijk +75
The main science aim of the BlackGEM array is to detect optical counterparts to gravitational wave mergers. Additionally, the array will perform a set of synoptic surveys to detect…
Detection of polarization neutral points in observations of the combined corona and sky during the 21 August 2017 total solar eclipse
Frans Snik, Steven P. Bos, Stefanie A. Brackenhoff +7
We report the results of polarimetric observations of the total solar eclipse of 21 August 2017 from Rexburg, Idaho (USA). We use three synchronized DSLR cameras with polarization…
Using all-sky optical observations for automated orbit determination and prediction for satellites in Low Earth Orbit
T. P. G. Wijnen, R. Stuik, M. Rodenhuis +2
We have used an existing, robotic, multi-lens, all-sky camera system, coupled to a dedicated data reduction pipeline, to automatically determine orbital parameters of satellites in…
BP Piscium: its flaring disk imaged with SPHERE/ZIMPOL
J. de Boer, J. H. Girard, H. Canovas +9
Whether BP Piscium (BP Psc) is either a pre-main sequence T Tauri star at d ~ 80 pc, or a post-main sequence G giant at d ~ 300 pc is still not clear. As a first-ascent giant, it i…
Performance of Silicon immersed gratings: Measurement, analysis and modelling
Michiel Rodenhuis, Paul J. J. Tol, Tonny H. M. Coppens +2
The use of Immersed Gratings offers advantages for both space- and ground-based spectrographs. As diffraction takes place inside the high-index medium, the optical path difference…
Surprising detection of an equatorial dust lane on the AGB star IRC+10216
S. V. Jeffers, M. Min, L. B. F. M. Waters +6
Understanding the formation of planetary nebulae remains elusive because in the preceding asymtotic giant branch (AGB) phase these stars are heavily enshrouded in an optically thic…
Magnetic field topology and chemical spot distributions in the extreme Ap star HD 75049
O. Kochukhov, N. Rusomarov, J. A. Valenti +7
Intermediate-mass, magnetic chemically peculiar (Ap) stars provide a unique opportunity to study the topology of stellar magnetic fields in detail and to investigate magnetically d…
Imaging the circumstellar environment of the young T Tauri star SU Aurigae
S. V. Jeffers, M. Min, H. Canovas +2
The circumstellar environments of classical T Tauri stars are challenging to directly image because of their high star-to-disk contrast ratio. One method to overcome this is by usi…
Three-dimensional magnetic and abundance mapping of the cool Ap star HD 24712 I. Spectropolarimetric observations in all four Stokes parameters
N. Rusomarov, O. Kochukhov, N. Piskunov +8
High-resolution spectropolarimetric observations provide simultaneous information about stellar magnetic field topologies and three-dimensional distributions of chemical elements.…
Are there tangled magnetic fields on HgMn stars?
O. Kochukhov, V. Makaganiuk, N. Piskunov +7
Several recent spectrophotometric studies failed to detect significant global magnetic fields in late-B HgMn chemically peculiar stars, but some investigations have suggested the p…
The color dependent morphology of the post-AGB star HD161796
M. Min, S. V. Jeffers, H. Canovas +3
Context. Many protoplanetary nebulae show strong asymmetries in their surrounding shell, pointing to asymmetries during the mass loss phase. Questions concerning the origin and the…
Magnetically Controlled Accretion on the Classical T Tauri Stars GQ Lupi and TW Hydrae
C. M. Johns-Krull, W. Chen, J. A. Valenti +8
We present high spectral resolution () Stokes polarimetry of the Classical T Tauri stars (CTTSs) GQ Lup and TW Hya obtained with the polarimetric upgrade to th…
The Extreme Polarimeter: Design, Performance, First Results & Upgrades
M. Rodenhuis, H. Canovas, S. V. Jeffers +4
Well over 700 exoplanets have been detected to date. Only a handful of these have been observed directly. Direct observation is extremely challenging due to the small separation an…
Constraining the Circumbinary Envelope of Z CMa via imaging polarimetry
H. Canovas, M. Min, S. V. Jeffers +2
Z CMa is a complex binary system, composed of a Herbig Be and an FU Ori star. The Herbig star is surrounded by a dust cocoon of variable geometry, and the whole system is surrounde…
Direct imaging of a massive dust cloud around R Coronae Borealis
S. V. Jeffers, M. Min, L. B. F. M. Waters +5
We present recent polarimetric images of the highly variable star R CrB using ExPo and archival WFPC2 images from the HST. We observed R CrB during its current dramatic minimum whe…
SPICES: Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems
Anthony Boccaletti, Jean Schneider, Wes Traub +28
SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and charact…
Magnetism, chemical spots, and stratification in the HgMn star phi Phoenicis
V. Makaganiuk, O. Kochukhov, N. Piskunov +7
Mercury-manganese (HgMn) stars have been considered as non-magnetic and non-variable chemically peculiar (CP) stars for a long time. However, recent discoveries of the variability…
No magnetic field in the spotted HgMn star mu Leporis
O. Kochukhov, V. Makaganiuk, N. Piskunov +7
Chemically peculiar stars of the mercury-manganese (HgMn) type represent a new class of spotted late-B stars, in which evolving surface chemical inhomogeneities are apparently unre…
Data Reduction Techniques for High Contrast Imaging Polarimetry. Applications to ExPo
H. Canovas, M. Rodenhuis, S. V. Jeffers +2
Imaging polarimetry is a powerful tool for detecting and characterizing exoplanets and circumstellar environments. Polarimetry allows a separation of the light coming from an unpol…
First detection of linear polarization in the line profiles of active cool stars
O. Kochukhov, V. Makaganiuk, N. Piskunov +6
The application of high-resolution spectropolarimetry has led to major progress in understanding the magnetism and activity of late-type stars. During the last decade, magnetic fie…
Chemical spots in the absence of magnetic field in the binary HgMn star 66 Eridani
V. Makaganiuk, O. Kochukhov, N. Piskunov +7
According to our current understanding, a subclass of the upper main sequence chemically peculiar stars, called mercury-manganese (HgMn), is non-magnetic. Nevertheless, chemical in…
The search for magnetic fields in mercury-manganese stars
V. Makaganiuk, O. Kochukhov, N. Piskunov +7
We performed a highly sensitive search for magnetic fields on a large set of HgMn stars. With the aid of a new polarimeter attached to the HARPS spectrometer at the ESO 3.6m-telesc…