Bibcode
Pereyra, A.; Rodrigues, C. V.; Magalhães, A. M.
Bibliographical reference
Astronomy and Astrophysics, Volume 538, id.A59
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2
2012
Journal
Citations
3
Refereed citations
1
Description
Aims: Our goal is to study the circumstellar environment
associated with each component of the wide intermediate-mass pre-main
sequence binary system PDS 144 using broadband
polarimetry. Methods: We present near-infrared (NIR) linear
polarimetric observations of PDS 144 gathered with
the IAGPOL imaging polarimeter along with the CamIV infrared camera at
the Observatório do Pico dos Dias (OPD). In addition, we
re-analyzed OPD archive optical polarization to separate the binary and
estimate the interstellar polarization using foreground stars.
Results: After discounting the interstellar component, we found that
both stars of the binary system are intrinsically polarized. The
polarization vectors at optical and NIR bands of both components are
aligned with the local magnetic field and the jet axis. These findings
indicate an interplay between the interstellar magnetic field and the
formation of the binary system. We also found that the PDS
144N is less polarized than its southern companion in the
optical. However, in the NIR PDS 144N is more
polarized. Our polarization data can only be explained by high
inclinations (i ≳ 80°) for the disks of both members. In
particular, comparisons of our NIR data with young stellar objects disk
models suggest predominantly small grains in the circumstellar
environment of PDS 144N. In spite of the different
grain types in each component, the infrared spectral indexes indicate a
coeval system. We also found evidence of coplanarity between the disks.
Based on observations obtained at the Observatório do Pico dos
Dias, LNA/MCT, Itajubá, Brazil.