Linear Polarization Features in the Quiet-Sun Photosphere: Structure and Dynamics

التفاصيل البيبلوغرافية
العنوان: Linear Polarization Features in the Quiet-Sun Photosphere: Structure and Dynamics
المؤلفون: Kianfar, S., Jafarzadeh, S., Mirtorabi, M. T., Riethmüller, T. L.
سنة النشر: 2018
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Solar and Stellar Astrophysics
الوصف: We present detailed characteristics of linear polarization features (LPFs) in the quiet-Sun photosphere from high resolution observations obtained with Sunrise/IMaX. We explore differently treated data with various noise levels in linear polarization signals, from which structure and dynamics of the LPFs are studied. Physical properties of the detected LPFs are also obtained from the results of Stokes inversions. The number of LPFs, as well as their sizes and polarization signals, are found to be strongly dependent on the noise level, and on the spatial resolution. While the linear polarization with signal-to-noise ratio $\geq4.5$ covers about 26% of the entire area in the least noisy data in our study (with a noise level of $1.7\times10^{-4}$ in the unit of Stokes $I$ continuum), the detected (spatially resolved) LPFs cover about 10% of the area at any given time, with an occurrence rate on the order of $8\times10^{-3}$ s$^{-1}$ arcsec$^{-2}$. The LPFs were found to be short lived (in the range of $30-300$ s), relatively small structures (radii of $\approx0.1-1.5$ arcsec), highly inclined, posing hG fields, and move with an average horizontal speed of 1.2 km s$^{-1}$. The LPFs were observed (almost) equally on both upflow and downflow regions, with intensity contrast always larger than that of the the average quiet-Sun.
Comment: 20 pages, 9 figures, Accepted for publication in the Solar Physics journal
نوع الوثيقة: Working Paper
DOI: 10.1007/s11207-018-1341-2
URL الوصول: http://arxiv.org/abs/1807.04633
رقم الأكسشن: edsarx.1807.04633
قاعدة البيانات: arXiv
الوصف
DOI:10.1007/s11207-018-1341-2