arXiv subjects
Publications and source records attributed to D. Elmore.
We analyze the co-alignment between Hinode's BFI-Gband images and simultaneous SP maps with the aim of characterizing the general off-sets between them and the second order non-linear effects in SP's slit scanning mechanism. We provide calibration functions and parameters to correct for the nominal pixel scales and positioning.
SPINOR is a new spectro-polarimeter that will serve as a facility instrument for the Dunn Solar Telescope at the National Solar Observatory. This instrument is capable of achromatic polarimetry over a very broad range of wavelengths, from 430 up to 1600 nm, allowing for the simultaneous observation of several visible and infrared spectral regions with full Stokes polarimetry. Another key feature of the design is its flexibility to observe virtually any combination of spectral lines, limited only by practical considerations (e.g., the number of detectors available, space on the optical bench, etc).
Ellerman bombs are bright emission features observed in the wings of H$α$, usually in the vicinity of magnetic concentrations. Here we show that they can also be detected in the Ca II infrared triplet lines, which are easier to interpret and therefore allow for more detailed diagnostics. We present full Stokes observations of the 849.8 and 854.2 nm lines acquired with the new spectro-polarimeter SPINOR. The data shows no significant linear polarization at the level of 3x10$^{-4}$. The circular polarization profiles exhibit measureable signals with a very intricate pattern of peaks. A non-LTE analysis of the spectral profiles emerging from these features reveal the presence of strong downflows (~10 km/s) in a hot layer between the upper photosphere and the lower chromosphere.
SPINOR is a new spectro-polarimeter that will serve as a facility instrument for the Dunn Solar Telescope at the National Solar Observatory. This instrument is capable of achromatic operation over a very broad range of wavelengths, from $\sim$400 up to 1600 nm, allowing for the simultaneous observation of several visible and infrared spectral regions with full Stokes polarimetry. Another key feature of the design is its flexibility to observe virtually any combination of spectral lines, limited only by practical considerations (e.g., the number of detectors available, space on the optical bench, etc). SPINOR is scheduled for commissioning by the end of 2005. In this paper we report on the current status of the project and present actual observations of active regions in the Ca II infrared triplet and the He I multiplet at 1083 nm.