Exploration of the Calibration and Development of the Spectral Extraction Procedure for the Rapid IMAger - Spectrometer
Abstract
The Rapid IMAger - Spectrometer (RIMAS) will study the afterglow of gamma-ray bursts in the near-infrared. In order to produce useful astronomical data, RIMAS must be calibrated to establish what wavelength corresponds to each pixel on the spectrometer's H2RG detectors. In the first phase of this study, several methods of determining the pixel number of spectral peaks were developed in Python and compared to find which produced the most accurate calibration curve. Three different approaches were attempted using test spectra taken by RIMAS of elements with known emission lines: finding the pixel number of peaks in a one-dimensional line spectrum, fitting two-dimensional Gaussians over the peaks and finding the pixel number of their maxima, and finding the centers of mass of the peaks at a certain intensity threshold, which was then varied. Once the pixel numbers of peaks were found, a linear regression with the known wavelengths of the spectral lines was performed to produce a calibration curve. After a comparison of the r2 value and the maximum percent difference between library and calibrated wavelengths produced by the different methods, the best calibration curve was shown to be produced by finding center of mass with an intensity threshold of 35%. The next phase of this project is to establish the spectral extraction pathway for RIMAS using Spextool. This requires the construction of line and wavelength calibration files specific to RIMAS, which will be incorporated into the existing Spextool pathway. Using this package, observers will have a pipeline to create calibration files and extract the spectrum of their target object. The extraction of data from RIMAS that this enables will be integral to researching distant gamma-ray bursts.
- Publication:
-
American Astronomical Society Meeting Abstracts #233
- Pub Date:
- January 2019
- Bibcode:
- 2019AAS...23314611K