HSTaXe

hstaxe is a Python package to extract spectra from all slitless spectroscopy modes provided by the Hubble Space Telescope Wide Field Camera 3 (WFC3) and the Advanced Camera for Surveys (ACS). It supports the features provided by the previous IRAF-based aXe package.

Installation

UPDATE (May 2022)

The WFC3 team has recently tested hstaxe installation and found three distinct pathways to get the package installed successfully. Each of these installations were tested with the HSTaXe WFC3 cookbook and were found to execute all the cookbook steps successfully. NOTE: These installation pathways were tested on macOS Catalina.

Option 1. Installing the PyPI release of HSTaXe (v.1.0.1):

Installing the latest released version of hstaxe with pip involves the following steps (conda is used to install some non-Python dependencies):

conda create --name hstaxe_test python=3
conda activate hstaxe_test
conda install gsl cfitsio make automake autoconf libtool pkg-config -y
conda install wcstools -c https://ssb.stsci.edu/astroconda -y
pip install hstaxe

Optionally install Jupyter:

pip install jupyter

Option 2. Installing the Astroconda release of HSTaXe (v.1.0.0):

The following steps should be followed to install hstaxe from using conda using the Astroconda channel. This installation should start by downloading only the conda_environment.yml file from this repository followed by creating a conda environment using this file:

conda create --name hstaxe_test --file conda_environment.yml

Activate this environment:

conda activate hstaxe_test

Install HSTaXe from Astroconda:

conda install hstaxe -c https://ssb.stsci.edu/astroconda

Option 3. Installing the development version of HSTaXe from source distribution:

These instructions describe the installation of the latest development version of the HSTaXe source code. This workflow involves the the creation of a new conda environment, retrieval of the source code from this repository (https://github.com/spacetelescope/hstaxe), and the installation of the HSTaXe software and its dependencies in that environment.

Create and activate a conda environment where hstaxe and all its dependencies will be installed in. We call it hstaxe_test in this example:

conda create --name hstaxe_test python=3

conda activate hstaxe_test

Install supporting packages before installing hstaxe:

conda install gsl cfitsio make automake autoconf libtool pkg-config -y

conda install wcstools -c https://ssb.stsci.edu/astroconda -y

Clone the hstaxe software from this repository:

git clone https://github.com/spacetelescope/hstaxe.git

Install hstaxe (and its dependencies):

cd hstaxe
pip install .

Notebooks and Examples

WFC3

The aXe WFC3 cookbook data can be downloaded by cloning this repository: https://github.com/npirzkal/aXe_WFC3_Cookbook

1. git clone https://github.com/npirzkal/aXe_WFC3_Cookbook.git

2. Enter the aXe_WFC3_Cookbook directory and work through aXe_WFC3_Cookbook.ipynb within the conda environment created as part of the hstaxe installation.

ACS

The aXe ACS cookbook and associated data can be downloaded from the following area: https://stsci.box.com/s/eo98zjtyccnoq7z73akfrx94jog3pg7j

Examples

There are also a couple simple test scripts in hstaxe/tests that can be run against the example data in the aXe cookbook:

• run_acs_cookbook.py: runs basic aXe against ACS data

• run_cookbook.py: runs basic aXe against WFC3 data from the cookbook

• run_cookbook_part2.py: runs axedrizzle against WFC3 data from the cookbook

Software Development History

This software was originally developed by the ACS group of the Space Telescope - European Coordinating Facility (ST-ECF). The ST-ECF is a department jointly run by the European Space Agency and the European Southern Observatory. It is located at the ESO headquarters at Garching near Munich. The ST-ECF staff supports the European astronomical community in exploiting the research opportunities provided by the earth-orbiting Hubble Space Telescope.

The developers have included, roughly in order of who has worked on the software:

Norbert Pirzkal, ST-ECF/STScI
Markus Demleitner, ST-ECF
Martin Kuemmel, ST-ECF
Richard Hook, ST-ECF/STScI
Howard Bushouse, STScI
Megan Sosey, STScI

Installation Requirements (for reference)

hstaxe has the following Python requirements:

• Python 3.7 or later
• numpy
• astropy
• stwcs
• stsci.imagestats
• drizzlepac
• photutils < 1.1.0
• drizzle

In addition to the above Python packages, hstaxe depends on the following C-based packages to be installed:

• cfitsio
• gsl
• libwcs from wcstools

These packages must be installed in your environment before you can install hstaxe. They can be compiled and installed locally or installed using pip and/or conda.

You will also need a C compiler suite (e.g., gcc or clang) to build hstaxe via pip from either PyPI or from the source distribution. In addition to the above required packages, the following packages are required to build hstaxe:

• make
• automake
• autoconf
• libtool
• pkg-config

Note that you may also need to install the c-blosc package as a dependency of the tables package on certain platforms (e.g., this is currently needed for macOS and Windows with Python 3.9 due to missing tables wheels on PyPI).