The 2008 outburst of EX Lup-silicate crystals in motion

A. Juhász, C. P. Dullemond, R. Van Boekel, J. Bouwman, P. Ábrahám, J. A. Acosta-Pulido, Th Henning, A. Kóspál, A. Sicilia-Aguilar, A. Jones, A. Moór, L. Mosoni, Zs Regály, G. Szokoly, N. Sipos

Research output: Article

35 Citations (Scopus)

Abstract

EXLup is the prototype of the EXor class of eruptive young stars. These objects show optical outbursts which are thought to be related to runaway accretion onto the star. In a previous study we observed in situ crystal formation in the disk of EXLup during its latest outburst in 2008, making the object an ideal laboratory to investigate circumstellar crystal formation and transport. This outburst was monitored by a campaign of ground-based and Spitzer Space Telescope observations. Here we modeled the spectral energy distribution (SED) of EXLup in the outburst from optical to millimeter wavelengths with a two-dimensional radiative transfer code. Our results showed that the shape of the SED at optical wavelengths was more consistent with a single-temperature blackbody than a temperature distribution. We also found that this single-temperature component emitted 80%-100% of the total accretion luminosity. We concluded that a thermal instability, the most widely accepted model of EXor outbursts, was likely not the triggering mechanism of the 2008 outburst of EXLup. Our mid-infrared Spitzer spectra revealed that the strength of all crystalline bands between 8 and 30μm increased right after the end of the outburst. Six months later, however, the crystallinity in the 10μm silicate feature complex decreased. Our modeling of the mid-infrared spectral evolution of EXLup showed that, although vertical mixing should be stronger during the outburst than in the quiescent phase, fast radial transport of crystals (e.g., by stellar/disk wind) was required to reproduce the observed mid-infrared spectra.

Original languageEnglish
Article number118
JournalAstrophysical Journal
Volume744
Issue number2
DOIs
Publication statusPublished - jan. 10 2012

Fingerprint

outburst
silicates
silicate
crystal
spectral energy distribution
crystals
stars
Space Infrared Telescope Facility
thermal instability
wavelengths
radiative transfer
crystallinity
temperature distribution
infrared spectra
luminosity
prototypes
temperature
accretion
wavelength
vertical mixing

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Juhász, A., Dullemond, C. P., Van Boekel, R., Bouwman, J., Ábrahám, P., Acosta-Pulido, J. A., ... Sipos, N. (2012). The 2008 outburst of EX Lup-silicate crystals in motion. Astrophysical Journal, 744(2), [118]. https://doi.org/10.1088/0004-637X/744/2/118

The 2008 outburst of EX Lup-silicate crystals in motion. / Juhász, A.; Dullemond, C. P.; Van Boekel, R.; Bouwman, J.; Ábrahám, P.; Acosta-Pulido, J. A.; Henning, Th; Kóspál, A.; Sicilia-Aguilar, A.; Jones, A.; Moór, A.; Mosoni, L.; Regály, Zs; Szokoly, G.; Sipos, N.

In: Astrophysical Journal, Vol. 744, No. 2, 118, 10.01.2012.

Research output: Article

Juhász, A, Dullemond, CP, Van Boekel, R, Bouwman, J, Ábrahám, P, Acosta-Pulido, JA, Henning, T, Kóspál, A, Sicilia-Aguilar, A, Jones, A, Moór, A, Mosoni, L, Regály, Z, Szokoly, G & Sipos, N 2012, 'The 2008 outburst of EX Lup-silicate crystals in motion', Astrophysical Journal, vol. 744, no. 2, 118. https://doi.org/10.1088/0004-637X/744/2/118
Juhász A, Dullemond CP, Van Boekel R, Bouwman J, Ábrahám P, Acosta-Pulido JA et al. The 2008 outburst of EX Lup-silicate crystals in motion. Astrophysical Journal. 2012 jan. 10;744(2). 118. https://doi.org/10.1088/0004-637X/744/2/118
Juhász, A. ; Dullemond, C. P. ; Van Boekel, R. ; Bouwman, J. ; Ábrahám, P. ; Acosta-Pulido, J. A. ; Henning, Th ; Kóspál, A. ; Sicilia-Aguilar, A. ; Jones, A. ; Moór, A. ; Mosoni, L. ; Regály, Zs ; Szokoly, G. ; Sipos, N. / The 2008 outburst of EX Lup-silicate crystals in motion. In: Astrophysical Journal. 2012 ; Vol. 744, No. 2.
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