124 citations · 1k across the 57 of their papers we have counts for
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High-precision broadband linear polarimetry of early-type binaries. V. The Binary System HD 165052 in Open Cluster NGC 6530
Yasir Abdul Qadir, Andrei V. Berdyugin, Vilppu Piirola +3
This study continues our investigation of early-type binaries using high-precision broad-band polarimetry, focusing on HD 165052, a massive O+O-type binary in the young cluster NGC…
Searching for magnetic fields in featureless white dwarfs with the DIPOL-UF polarimeter at the Nordic Optical Telescope
A. Berdyugin, J. D. Landstreet, S. Bagnulo +2
About 20% of the white dwarfs possess a magnetic field that may be detected by the splitting and/or polarization of their spectral lines. As they cool, the effective temperatures o…
High-precision broadband linear polarimetry of early-type binaries IV. Binary system of DH Cephei in the open cluster of NGC 7380
Yasir Abdul Qadir, Andrei V. Berdyugin, Vilppu Piirola +2
DH Cephei is a prominent O+O-type binary system in the NGC 7380 open cluster. Our high-precision multi-band polarimetry demonstrates synchronous linear polarization variations with…
High-precision broadband linear polarimetry of early-type binaries III. AO Cassiopeiae revisited
Yasir Abdul Qadir, Andrei V. Berdyugin, Vilppu Piirola +2
The fact that the O-type close binary star system AO~Cassiopeiae exhibits variable phase-locked linear polarization has been known since the mid-1970s. In this work, we re-observe…
Discovery of magnetic fields in five DC white dwarfs
Andrei V. Berdyugin, Vilppu Piirola, Stefano Bagnulo +2
About half of white dwarfs (WDs) evolve to the DC state as they cool; the others become DQ or (temporarily?) DZ WDs. The recent magnetic survey of the local 20 pc volume has establ…
Limiting the accretion disk light in two mass transferring hot subdwarf binaries
Kunal Deshmukh, Thomas Kupfer, Pasi Hakala +6
We report the results from follow-up observations of two Roche-lobe filling hot subdwarf binaries with white dwarf companions predicted to have accretion disks. ZTF J213056.71+4420…