MAXI Data


MAXI Archive data are released from DARTS at ISAS/JAXA on October 2nd, 2017. Data archive are updated real-time (typical delay 15 minutes), and released from DARTS at ISAS/JAXA, and mirrored to HEASARC at NASA/GSFC. The MAXI archive data are processed and screened using the latest CALDB and auxiliary data. Users do not need screening. When new CALDB is released, archive data are updated. Using MAXI specific ftools and CALDB (will be included into HEAsoft), users can analyze data easily (please see the Analysis page).

Data Download

Users can download event files and auxiliary files corresponding to a specified sky region by a convenient tool, mxdownload. Or, users can locally have the entire MAXI archive (~1.4 Tbytes for 7 years). To install mxdownload or download the entire MAXI archive, please follow the Preparation page. For how to obtain archive data using mxdownload, please see the Data Analysis page.

The structure of MAXI data Archive

All the data are found at http:/darts.isas.jaxa.jp/pub/maxi/mxdata. Under the obs/ directory, event data are put into a directory of every 1000 days ( MJD5xxxx/), and then each day ( MJDxxxxxx/). The directory of each day has events/ and auxil/ directories, which contain event files and auxiliary files for attitude, orbit, time, ISS data, GSC time data, MKF, HK etc. The directory events/ has 3 directories, gsc_med/ gsc_low/ ssc_med/ for GSC and SSC, for bit rate low/med. Daily events are divided into 768 files, corresponding to each HEALPix region of the all sky.


There is a lack of data for different reasons: MAXI shutdown, downlink problems, processing errors etc. The detailed information about those problems will be appeared.

Last Modified: 10 October 2017