Analysis of the Hitomi Perseus data

The XRISM analysis software is not yet public at the time of the school. However, the Perseus observations of Hitomi and the Hitomi software are accessible to everyone. They provide a good example of what a typical data analysis thread with XRISM will look like.

In this hands-on session, we will analyse a Perseus observation performed by Hitomi from the original observation files using HEASOFT. We will perform the following steps:

  • Filter the data (good time intervals and grades),

  • Extract images,

  • Extract lightcurves,

  • Generate expected background spectra,

  • Extract spectra,

  • Generate responses and effective area files,

  • Fit the spectrum.

This analysis involves quite a number of long commands, therefore we provide the analysis to you in the form of a Jupyter notebook. The goal of this session is to run the analysis step-by-step and be able to make changes to it if necessary.

Running the notebook on Sciserver

Make sure that you have setup the Sciserver environment like described in Software installation. Once you have the Jupyter-lab running on your HEASOFT image on Sciserver, make sure that you start a new terminal with the (spex) terminal environment.

Once you have successfully entered the (spex) environment, you can go to your own storage space in the Jupyterlab terminal (replace <user> by your user name):

(spex) idies@aaaa:~$ cd ~/workspace/Storage/<user>/persistent

You can download the notebook and support files into your directory using this git command:

(spex) idies@aaaa:~/workspace/Storage/<user>/persistent$ git clone https://github.com/summerschool-ahead2020/xrism-hands-on.git

Then make the links to the Hitomi data and background files:

(spex) idies@aaaa:~/workspace/Storage/<user>/persistent$ cd xrism-hands-on
(spex) idies@aaaa:~/workspace/Storage/<user>/persistent/xrism-hands-on$ ln -s /FTP/hitomi/data/obs/1/100040030 100040030
(spex) idies@aaaa:~/workspace/Storage/<user>/persistent/xrism-hands-on$ ln -s /FTP/hitomi/data/nxb_20170510 NXB

And unzip the raytrace fits file in the products_sxs directory:

(spex) idies@aaaa:~/workspace/Storage/<user>/persistent/xrism-hands-on$ cd products_sxs
(spex) idies@aaaa:~/workspace/Storage/<user>/persistent/xrism-hands-on/products_sxs$ gunzip raytrace_ah100040030sxs_p0px1010_ptsrc.fits.gz

Running the notebook on your laptop

Make sure that you have setup your laptop environment like described in Software installation. Once you have the Jupyter-lab running in the (spex) conda environment, you can start a terminal and download the notebook with support files:

(spex) user@unix:~$ git clone https://github.com/summerschool-ahead2020/xrism-hands-on.git
(spex) user@unix:~$ cd xrism-hands-on

Next, we unzip the raytrace file and download the other needed files:

(spex) user@unix:~/xrism-hands-on$ cd products_sxs
(spex) user@unix:~/xrism-hands-on/products_sxs$ gunzip raytrace_ah100040030sxs_p0px1010_ptsrc.fits.gz
(spex) user@unix:~/xrism-hands-on/products_sxs$ cd ..
(spex) user@unix:~/xrism-hands-on$

Download the HITOMI Perseus data and background files

In addition, you will need the Perseus data from Hitomi, which can be downloaded using (for example) the wget program:

wget -q -nH --no-check-certificate --cut-dirs=5 -r -l0 -c -N -np -R 'index*' -erobots=off --retr-symlinks https://heasarc.gsfc.nasa.gov/FTP/hitomi/data/obs/1//100040030/sxs/
wget -q -nH --no-check-certificate --cut-dirs=5 -r -l0 -c -N -np -R 'index*' -erobots=off --retr-symlinks https://heasarc.gsfc.nasa.gov/FTP/hitomi/data/obs/1//100040030/auxil/

The Non-X-ray Background (NXB) data can be downloaded here:

wget https://darts.jaxa.jp/pub/hitomi/data/nxb_20170510/ah_sxs_nxbafmar4_20140101v001.evt.gz
wget https://darts.jaxa.jp/pub/hitomi/data/nxb_20170510/ah_gen_nxbehk_20140101v002.fits.gz

Starting jupyter notebook or jupyter lab

In the spex conda environment, you can start Jupyter notebook or Jupyter Lab:

(spex) user@unix:~/xrism-hands-on> jupyter notebook

or:

(spex) user@unix:~/xrism-hands-on> jupyter-lab

A browser will open Jupyter and there you can open Analyze_Perseus.ipynb.