Related papers: High-resolution observations of active region moss…
The High-resolution Coronal Imager (Hi-C) has provided Fe XII 193A images of the upper transition region moss at an unprecedented spatial (~0.3-0.4 arcsec) and temporal (5.5s) resolution. The Hi-C observations show in some moss regions…
The recent launch of the High resolution Coronal imager (Hi-C) provided a unique opportunity to study the EUV corona with unprecedented spatial resolution. We utilize these observations to investigate the properties of low frequency (50-200…
We present new measurements of the time variability of intensity, Doppler and non-thermal velocities in moss in an active region core observed by the EUV Imaging Spectrometer on Hinode in 2007, June. The measurements are derived from…
Observations of transition region emission in solar active regions represent a powerful tool for determining the properties of hot coronal loops. In this Letter we present the analysis of new observations of active region moss taken with…
We present a study of the physical plasma parameters such as electron temperature, electron density, column depth and filling factors in the moss regions and their variability over a short (an hour) and a long period (5 consecutive days) of…
Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the active regions. In this paper we have used an active region observation recorded by…
Context: Studying the problem of active region heating requires precise measurements of physical plasma parameters such as electron density, temperature etc. It is also important to understand the relationship of coronal structures with the…
Many models for coronal loops have difficulty explaining the observed EUV brightness of the transition region, which is often significantly less than theoretical models predict. This discrepancy has been addressed by a variety of approaches…
The moss is the area at the footpoint of the hot (3 to 5 MK) loops forming the core of the active region where emission is believed to result from the heat flux conducted down to the transition region from the hot loops. Studying the…
Magnetic loops filled with hot plasma are the main building blocks of the solar corona. Usually they have lengths of the order of the barometric scale height in the corona that is 50 Mm. Previously it has been suggested that miniature…
The Soft X-ray intensity of loops in active region cores and corresponding footpoint, or moss, intensity observed in the EUV remain steady for several hours of observation. The steadiness of the emission has prompted many to suggest that…
Fine-scale structure in the corona appears not to be well resolved by current imaging instruments. Assuming this to be true offers a simple geometric explanation for several current puzzles in coronal physics, including: the apparent…
The "middle corona" is a critical transition between the highly disparate physical regimes of the lower and outer solar corona. Nonetheless, it remains poorly understood due to the difficulty of observing this faint region (1.5-3 solar…
Understanding how the solar corona is structured is of fundamental importance to determining how the Sun's upper atmosphere is heated to high temperatures. Recent spectroscopic studies have suggested that an instrument with a spatial…
High-frequency wave phenomena present a great deal of interest as one of the possible candidates to contribute to the energy input required to heat the corona as a part of the AC heating theory. However, the resolution of imaging…
We study the high frequency dynamics in the braided magnetic structure of an active region (AR 11520) moss as observed by High-Resolution Coronal Imager (Hi-C). We detect quasi periodic flows and waves in these structures. We search for…
The high temporal, spatial and spectral resolution of Interface Region Imaging Spectrograph (IRIS) has provided new insights into the understanding of different small-scale processes occurring at the chromospheric and transition region (TR)…
Decaying active region 10942 is investigated from 4:00-16:00 UT on February 24, 2007 using a suite of EUV observing instruments. Results from Hinode/EIS, STEREO and TRACE show that although the active region has decayed and no sunspot is…
Plasma outflows from the edges of active regions have been suggested as a possible source of the slow solar wind. Spectroscopic measurements show that these outflows have an enhanced elemental composition, which is a distinct signature of…
We describe the characteristics and evolution of the magnetic field and chromospheric emission in an active region core observed by the Solar Optical Telescope on Hinode. Consistent with previous studies, we find that the moss is unipolar,…