Use of HEASARC Data

HEASARC materials are all available freely for your use.

If using the HEASARC service made a significant contribution to a research project, please make the following acknowledgement in any resulting publication:

"This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC."

Some of our data are provided to us from other agencies such as JAXA and ESA. Specific wording for such missions is listed here:

• XMM: The XMM-Newton data are open and free to use by everyone worldwide for non-commercial purposes, provided that proper acknowledgment is given. When publishing a paper using XMM-Newton data, the following text shall be included, preferably as a footnote to the title:
  "Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA".