High-resolution polarimetry of Parsamian 21: Revealing the structure of an edge-on FU Ori disc

Á Kóspál, P. Ábrahám, D. Apai, D. R. Ardila, C. A. Grady, Th Henning, A. Juhász, D. W. Miller, A. Moór

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


We present the first high spatial resolution near-infrared direct and polarimetric observations of Parsamian 21, obtained with the Nasmyth Adaptive Optics System-CONICA instrument at the Very Large Telescope (VLT). We complemented these measurements with archival infrared observations, such as Hubble Space Telescope (HST)/Wide Field Planetary Camera 2 (WFPC2) imaging, HST/Near Infrared Camera and Multi-Object Spectrometer (NICMOS) polarimetry, photometry with the Spitzer Space Telescope's Infrared Array Camera (IRAC) and Multiband Imaging Photometer (MIPS), spectroscopy with Spitzer's Infrared Spectrograph (IRS), as well as Infrared Space Observatory (ISO) photometry. Our main conclusions are as follows: (1) we argue that Parsamian 21 is probably an FU Orionis-type object (FUor); (2) Parsamian 21 is not associated with any rich cluster of young stars; (3) our measurements reveal a circumstellar envelope, a polar cavity and an edge-on disc; the disc seems to be geometrically flat and extends from approximately 48 to 360 au from the star; (4) the spectral energy distribution (SED) can be reproduced with a simple model of a circumstellar disc and an envelope; (5) within the framework of an evolutionary sequence of FUors proposed by Green et al. and Quanz et al., Parsamian 21 can be classified as an intermediate-aged object.

Original languageEnglish (US)
Pages (from-to)1015-1028
Number of pages14
JournalMonthly Notices of the Royal Astronomical Society
Issue number3
StatePublished - Jan 2008


  • Circumstellar matter
  • Infrared: stars
  • Stars: individual: Parsamian 21
  • Stars: pre-main sequence
  • Techniques: polarimetric

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'High-resolution polarimetry of Parsamian 21: Revealing the structure of an edge-on FU Ori disc'. Together they form a unique fingerprint.

Cite this