Hello, Dr. Tan|
1) I am copying this email to the XRT community. The "XRT_Users" email list is for users to help each other with questions like this.
2) As you might know, there are 2 ways that filter data might be used to calculate the temperature and emission measure.
2a) One way is with filter-ratios. This way only requires 2 filters, and assumes the plasma is isothermal. Some of our colleagues have developed some software for this, although it is not yet provided in the XRT SSWIDL tree. Narukage-san, can you speak to this? Is there a "xrt_teem.pro" program available?
2b) Another way is with DEM inversion. This way requires data in several nearly simultaneous filters (at least 4 or 5), but allows the plasma to be "multithermal" (ie, a superposition of many temperatures along the line of sight). The code for this is called "xrt_dem_iterative2.pro", and is located in the HINODE/XRT SSWIDL tree. There is a lot of documentation in the header of that program to explain its usage. However, it must assume that the user is already familiar with the concepts of DEM analysis.