RHESSI Microflare List

From RHESSI Wiki

The RHESSI microflar list was created through the use of a new search algorithm developed by S. Christe and applied to the RHESSI 6-12 keV energy range during the first six years of the mission. The algorithm was developed by myself and is described fully in a paper which is published in ApJ. This paper (along with part II by Iain Hannah) describes the most recent analysis of this list as well as how the list was created.

Summary characteristics of the microflare list

• Created through a sensitive search of the 6-12 keV energy range as observed by RHESSI from March 2002 to March 2007.
• Contains a total of 25,705 events, 93.7% of which have been confirmed to be of solar origin through imaging.
• Ignores all times during RHESSI shutter motions which means that large GOES C class flares and above are not included.
• This list is NOT a subset of the official RHESSI flare list created by Jim McTiernan and included in SSW or in the HESSI GUI. Some overlap may exist between the two lists. In general, the official RHESSI flare list includes larger events than this microflare list. The microflare list contains events which are mostly GOES B class events and smaller (not background subtracted).

Accessing the list

Thanks to Sam Freeland, an IDL function exists which can automatically access the microflare list given a network connection. The function, ssw_getrhessi_schriste_uflares.pro, is now part of the SSW library and therefore in all likelihood it is already installed in your machine. The documentation follows.

 function ssw_getrhessi_schriste_uflares, t0, t1, refresh=refresh
 ;Input Parameters:
 ;t0, t1 - optional time or time range - default=full list 
 ;
 ;Output:
 ;function returns structure vector, 1 per event
 ;
 ; Calling Examples:
 ; IDL> uf=ssw_getrhessi_schriste_uflares() ; full list
 ; IDL> uf=ssw_getrhessi_schriste_uflares(time0, time1) ; all in range

Getting the list

The list is available in various formats and includes the start and end time along with the peak time in UTC of the event, all defined by the 6-12 keV energy range. More information could be added if requested. The various options follow.

• The Microflare list as a plain text file.
• The Microflare list as an HTML file. Each event is indexed and linked to a light curve for ease of browsing.
• The Microflare list as an IDL save file. In order to load the file use the ‘RESTORE’ command. The microflare list is stored in an anonymous structure called ‘flare_list’ with the tags ’start_time’, ‘end_time’, and ‘peak_time’. The times are stored as anytim compatible text strings. Each event is an element of the structure so the start time of event #10 is referenced as flare_list[9].start_time.

For studies involving other instrument it is sometimes useful to have the RHESSI observations times (for evaluating coincidence rates for example). I’ve therefore also create an exaustive list of all of the RHESSI observations times available as a text file (coming soon here!). This observation list only takes into account RHESSI eclipse and passes through the SAA during which RHESSI is not available. It does NOT include off-pointing times or other events which made RHESSI data unavailable.

If you have any questions about the list send an email to steven.d.christe@nasa.gov. If this flare list is a primary data source in your research co-authorship is requested if any publications or presentation result from it and please reference Christe et al. (2008) (bibtex entry).