Polarimetric differential imaging with VLT/NACO

Astronomy and Astrophysics, vol. 684, pp. A73

Abstract

Context. The observed diversity of exoplanets can possibly be traced back to the planet formation processes. Planet-disk interactions induce sub-structures in the circumstellar disk that can be revealed via scattered light observations. However, a high-contrast imaging technique such as polarimetric differential imaging (PDI) must first be applied to suppress the stellar diffraction halo. Aims. In this work we present the PDI PiPelIne for NACO data (PIPPIN), which reduces the archival polarimetric observations made with the NACO instrument at the Very Large Telescope. Prior to this work, such a comprehensive pipeline to reduce polarimetric NACO data did not exist. We identify a total of 243 datasets of 57 potentially young stellar objects observed before NACO’s decommissioning. Methods. The PIPPIN pipeline applies various levels of instrumental polarisation correction and is capable of reducing multiple observing setups, including half-wave plate or de-rotator usage and wire-grid observations. A novel template-matching method is applied to assess the detection significance of polarised signals in the reduced data. Results. In 22 of the 57 observed targets, we detect polarised light resulting from a scattering of circumstellar dust. The detections exhibit a collection of known sub-structures, including rings, gaps, spirals, shadows, and in- or outflows of material. Since NACO was equipped with a near-infrared wavefront sensor, it made unique polarimetric observations of a number of embedded protostars. This is the first time detections of the Class I objects Elia 2-21 and YLW 16A have been published. Alongside the outlined PIPPIN pipeline, we publish an archive of the reduced data products, thereby improving the accessibility of these data for future studies.

Authors 12

1. S. de Regt Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , P.O. Box 9513 , 2300 RA , Leiden , The Netherlands

   Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA, Leiden, The Netherlands

2. C. Ginski Aachen Leiden Observatory

   Leiden University · Ollscoil na Gaillimhe – University of Galway · Leiden Observatory · University of Amsterdam

   Affiliation as printed

   Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands

   Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA, Leiden, The Netherlands

   School of Natural Sciences, Center for Astronomy, University of Galway, Galway, H91 CF50, Ireland

3. Matthew A. Kenworthy Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory , Leiden University , P.O. Box 9513 , 2300 RA , Leiden , The Netherlands

   Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA, Leiden, The Netherlands

4. C. Cáceres

   Universidad Andrés Bello · Millenium Nucleus for Planet Formation

   Affiliation as printed

   Instituto de Astrofísica , Facultad de Ciencias Exactas , Universidad Andres Bello , Av. Fernández Concha 700 , Santiago , Chile

   Núcleo Milenio de Formación Planetaria (NPF) , Chile

   Instituto de Astrofísica, Facultad de Ciencias Exactas, Universidad Andres Bello, Av. Fernández Concha 700, Santiago, Chile

   Núcleo Milenio de Formación Planetaria (NPF), Chile

5. A. Garufi

   Arcetri Astrophysical Observatory · National Institute for Astrophysics

   Affiliation as printed

   INAF , Osservatorio Astrofisico di Arcetri , Largo Enrico Fermi 5 , I-50125 Firenze , Italy

   INAF, Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125 Firenze, Italy

6. Tim M. Gledhill

   University of Hertfordshire

   Affiliation as printed

   Department of Physics, Astronomy & Mathematics , University of Hertfordshire , College Lane , Hatfield , Hertfordshire AL10 9AB , UK

   Department of Physics, Astronomy & Mathematics, University of Hertfordshire, College Lane, Hatfield, Hertfordshire AL10 9AB, UK

7. Antonio S. Hales

   National Radio Astronomy Observatory · Atacama Large Millimeter Submillimeter Array

   Affiliation as printed

   Joint ALMA Observatory , Avenida Alonso de Córdova 3107 , Vitacura 7630355 , Santiago , Chile

   National Radio Astronomy Observatory , 520 Edgemont Road , Charlottesville , VA 22903-2475 , United States of America

   Joint ALMA Observatory, Avenida Alonso de Córdova 3107, Vitacura 7630355, Santiago, Chile

   National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475, United States of America

8. N. Huélamo

   Consejo Superior de Investigaciones Científicas · Centro de Astrobiología

   Affiliation as printed

   Centro de Astrobiología (CAB) , CSIC-INTA , ESAC Campus , Camino bajo del Castillo s/n , E-28692 Villanueva de la Cañada , Madrid , Spain

   Centro de Astrobiología (CAB), CSIC-INTA, ESAC Campus, Camino bajo del Castillo s/n, E-28692 Villanueva de la Cañada, Madrid, Spain

9. Á. Kóspál

   Eötvös Loránd University · Konkoly Observatory · Max Planck Institute for Astronomy · HUN-REN Research Centre for Astronomy and Earth Sciences

   Affiliation as printed

   CSFK, MTA Centre of Excellence, Konkoly-Thege Miklós út 15-17, 1121 Budapest, Hungary

   ELTE Eötvös Loránd University, Institute of Physics, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary

   Konkoly Observatory, HUN-REN Research Centre for Astronomy and Earth Sciences, Konkoly-Thege Miklós út 15-17, 1121 Budapest, Hungary

   Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

10. Maxwell A. Millar‐Blanchaer

    University of California, Santa Barbara

    Affiliation as printed

    Department of Physics , University of California , Broida Hall , Santa Barbara , CA 93106 , USA

    Department of Physics, University of California, Broida Hall, Santa Barbara, CA 93106, USA

11. Sebastian Perez M.

    Universidad de Santiago de Chile

    Affiliation as printed

    Center for Interdisciplinary Research in Astrophysics and Space Exploration (CIRAS), Universidad de Santiago, Chile

    Departamento de Fisica, Universidad de Santiago de Chile, Av. Victor Jara 3659, Santiago, Chile

    Millennium Nucleus on Young Exoplanets and their Moons (YEMS), Chile

12. Matthias R. Schreiber

    Millenium Nucleus for Planet Formation · Universidad Técnica Federico Santa María

    Affiliation as printed

    Departamento de Física , Universidad Técnica Federico Santa María , Av. España 1680 , Valparaíso , Chile

    Núcleo Milenio de Formación Planetaria (NPF) , Chile

    Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaíso, Chile

    Núcleo Milenio de Formación Planetaria (NPF), Chile