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Title: MODELING MID-INFRARED VARIABILITY OF CIRCUMSTELLAR DISKS WITH NON-AXISYMMETRIC STRUCTURE

Abstract

Recent mid-infrared observations of young stellar objects have found significant variations possibly indicative of changes in the structure of the circumstellar disk. Previous models of this variability have been restricted to axisymmetric perturbations in the disk. We consider simple models of a non-axisymmetric variation in the inner disk, such as a warp or a spiral wave. We find that the precession of these non-axisymmetric structures produces negligible flux variations but a change in the height of these structures can lead to significant changes in the mid-infrared flux. Applying these models to observations of the young stellar object LRLL 31 suggests that the observed variability could be explained by a warped inner disk with variable scale height. This suggests that some of the variability observed in young stellar objects could be explained by non-axisymmetric disturbances in the inner disk and this variability would be easily observable in future studies.

Authors:
;  [1]
  1. Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)
Publication Date:
OSTI Identifier:
21457056
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 719; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/719/2/1733
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICAL METHODS AND COMPUTING; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIAL SYMMETRY; MAIN SEQUENCE STARS; PERTURBATION THEORY; SCALE HEIGHT; SIMULATION; DIMENSIONS; HEIGHT; STARS; SYMMETRY

Citation Formats

Flaherty, K. M., and Muzerolle, J., E-mail: kflaherty@as.arizona.ed. MODELING MID-INFRARED VARIABILITY OF CIRCUMSTELLAR DISKS WITH NON-AXISYMMETRIC STRUCTURE. United States: N. p., 2010. Web. doi:10.1088/0004-637X/719/2/1733.
Flaherty, K. M., & Muzerolle, J., E-mail: kflaherty@as.arizona.ed. MODELING MID-INFRARED VARIABILITY OF CIRCUMSTELLAR DISKS WITH NON-AXISYMMETRIC STRUCTURE. United States. doi:10.1088/0004-637X/719/2/1733.
Flaherty, K. M., and Muzerolle, J., E-mail: kflaherty@as.arizona.ed. 2010. "MODELING MID-INFRARED VARIABILITY OF CIRCUMSTELLAR DISKS WITH NON-AXISYMMETRIC STRUCTURE". United States. doi:10.1088/0004-637X/719/2/1733.
@article{osti_21457056,
title = {MODELING MID-INFRARED VARIABILITY OF CIRCUMSTELLAR DISKS WITH NON-AXISYMMETRIC STRUCTURE},
author = {Flaherty, K. M. and Muzerolle, J., E-mail: kflaherty@as.arizona.ed},
abstractNote = {Recent mid-infrared observations of young stellar objects have found significant variations possibly indicative of changes in the structure of the circumstellar disk. Previous models of this variability have been restricted to axisymmetric perturbations in the disk. We consider simple models of a non-axisymmetric variation in the inner disk, such as a warp or a spiral wave. We find that the precession of these non-axisymmetric structures produces negligible flux variations but a change in the height of these structures can lead to significant changes in the mid-infrared flux. Applying these models to observations of the young stellar object LRLL 31 suggests that the observed variability could be explained by a warped inner disk with variable scale height. This suggests that some of the variability observed in young stellar objects could be explained by non-axisymmetric disturbances in the inner disk and this variability would be easily observable in future studies.},
doi = {10.1088/0004-637X/719/2/1733},
journal = {Astrophysical Journal},
number = 2,
volume = 719,
place = {United States},
year = 2010,
month = 8
}
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