Other
Scientific paper
Jan 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011aas...21734032f&link_type=abstract
American Astronomical Society, AAS Meeting #217, #340.32; Bulletin of the American Astronomical Society, Vol. 43, 2011
Other
1
Scientific paper
Recent studies have uncovered numerous examples of mid-infrared (mid-IR) variability in young stellar objects (YSOs). There are several possible physical mechanisms that may be responsible for these variations. We have obtained and analyzed multi-epoch near-infrared (NIR) spectra for five YSOs in ρ-Ophiuchus with contemporaneous mid-IR light curves obtained as part of the YSOVAR Spitzer/IRAC survey. These targets were chosen due to their history of active mass accretion: our spectral measurements demonstrate the time dependence of these YSOs mass accretion rate through measurements of the strength of their Brγ and Paβ emission over 10 epochs. While we find that this rate is variable over timescales of days to weeks, we do not see a correlation
between their mid-IR light curves and any of the following parameters: (1) mass accretion rate, (2) changes in K-band veiling, or (3) variability in extinction along the line of sight. We conclude that the physical processes driving these variations arise in a region of the circumstellar disk that is not directly affected by ongoing mass accretion. We also look for correlations between mass accretion rate and the strength of the components of the He λ10830 line. The strength of the blueshifted absorption, which is thought to be an indication of accretion-induced stellar winds, does not appear to correlate with the accretion rate. However, the redshifted emission, where present in our spectra, does show both quantitative and qualitative similarities with the accretion-sensitive HI lines, including commensurate variability, and thus could potentially be used as another spectral signature for mass accretion in young stars.
Covey Kevin R.
Faesi Christopher
Gutermuth Robert
Morales-Calderon Maria
Plavchan Peter
No associations
LandOfFree
A NIR Spectroscopic Study of Potential Mid-IR Variability Mechanisms for Young Stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A NIR Spectroscopic Study of Potential Mid-IR Variability Mechanisms for Young Stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A NIR Spectroscopic Study of Potential Mid-IR Variability Mechanisms for Young Stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1402821