GCN/SUZAKU-WAM GRB and Transient Light Curves

NOTE: The end of SUZAKU science operations (and therefore GCN Notices) was sometime in June of 2015.


  1. Introduction
  2. Motivation
  3. Content
  4. Occurance Rate and Confidence Level
  5. Data Quality
  6. Positions and Error
  7. Time Delays
  8. Formats
  9. Filtering
  10. Error Boxes
  11. Test Notices
  12. Recognition
  13. Further Help
  14. Archiving
  15. Misc
  16. E-mail Examples
  17. Cell/Pager Examples
  18. Short-form Cell/Pager Examples
  19. Subject-only Cell/Pager Examples


The GCN system has been modified to incorporate the distribution
of lightcurves of GRBs, other unknown transients, and non-astrophysically-caused triggers
detected by the SUZAKU-WAM instrument.

SUZAKU-WAM will trigger about 11 times per month, of which ~60% are astrophysical
(eg GRBs, SGRs) and ~5% are solar flares, the rest are noise.
These detections are discovered during automated processing of the downlinked data.
They are sent to GCN and automatically distributed to those "sites"
that have the SUZAKU_LC notice type enabled and that meet their filtering specifications.
The typical time delays range from ~5 to ~48 hours.
These notices contain only the trigger date/time and the countrate lightcurve;
there is no positional information available for this type.

All the GCN/SUZAKU_LC Notices are archived within the GCN website in the Table of SUZAKU Trigger Lightcurves.


These Suzaku-WAM lightcurve notices can be used:
1) with just the trigger_time for temporal correlations with other mission-instrument
trigger times (thus allowing the analysis threshold to be lowered for each), and
2) with the actual lightcurve for more detailed (ie shape) correlations.
[Adding SUZAKU_LC is part of a larger, on-going effort within GCN to facilitate
above- and below-threshold correlations between same-/multi-messenger instruments.]


SUZAKU_LC Notice contains lightcurve (ie countrate) increases from the WAM shields
that exceed a threshold value (over some time interval). The energy range
of the lightcurves is approximately 50-240 keV (dependant on detector gain;
this energy range has been reduced from the full 50-5000 keV WAM range for use
in correlations with other instruments in the IPN effort).
These countrate increases can be caused by GRBs, other x-ray/hard_x-ray transients, and noise.
The Notices contain the date, time, and trigger criteria (timescale and energy_band).
There are two sub-types: (a) those resulting from an on-board trigger of countrate increase (BST events),
and (b) those resulting from ground-processing scanning looking for rate increases (TRN events).
For the BST triggers, the time resolution is 1/64 sec and the coverage is 64 sec
(8 sec before and 56 sec after the trigger), and for the TRN events the sampling is 1 sec
and 300 sec coverage (100s sec before and 200 sec after the detection).
Currently, only the BST subtype is distributed -- the TRN may be distributed at a later date.

Occurance Rate and Confidence Level

There will be about 11 Suzaku-WAM triggers per month (109 in the first 10 months of 2013).
Given the telemetry and data (re)processing methods used bt the Suzaku Team,
~50% will have duplicate notifications.
About one third of the triggers will have temporal coincidences with INTEGRAL-SPIACS and
KONUS-Wind, and therefore have a very high confidence of being astrophysical.

Data Quality

These lightcurves are the result of rapid automated processing and do not have
the full calibration applied to them. They are being provided in this quicklook form
with minimal delay to allow for rapid use and response by the community.
Ultimately, any analysis that uses this WAM data that results in a publication
should use the well-calibrated data from the official Suzaku processing pipeline.
Please contact the Suzaku-WAM team for such data products.

Positions and Errors

This notice type does NOT contain any position information (unlike most of the GCN Notice types).

Time Delays

The Suzaku automated ground software finds the transients and sends the message to GCN.
The typical time delays range from ~5 to ~48 hours.


Samples of the E-mail, Cell/Pager, Short-form Cell/Pager, and Subject-only
distribution methods of the GCN/SUZAKU_LC Notice type are included below.
The format is very similar to the other spacecraft-instrument notices -- the GCN-standard "TOKEN: value" format.
(Also available in XML format via email and sockets.)

The socket packet contents and format are similar to the other mission-specific packet types
and are described in detail in the socket packet definition document.
This document also has explanations of the various fields in the packet
(their content, values, and implications for use),
and those same fields are manifested in the email and cell/pager formats.
(Therefore, it is useful for email-based recipients to read the socket packet definition document
to understand the contents of the email/cell/pager notifications are.)
The SUZAKU_LC Notice is type=148.

NUM   TYPE       SOCKET  FullFmt_EMAIL    PAGER/CELL         XML
                            w/Txt       (all 4 variants)
===   ========   ======  =============  ================     ====
148   SUZAKU_LC      P        B               B               B&A

P = Packet (the GCN-standard 40 longword socket packet format)
B = Body of email (the GCN-standard "TOKEN: value" format)
A = As an attachment to a full-format email (GIF, JPEG, PS, PDF, and Text).


All the normal GCN filtering functions are applicable, but given the special temporal-only
nature of this notice type, the only functions that are valid are:
type, time_delay, time-of-day window.

Test Notices

There is no "test" type for the SUZAKU_LC Notice type.


Sites are encouraged to acknowledge SUZAKU and GCN in their publications
based on any observations or analyses using these GCN/SUZAKU_LC timestamps or lightcurves.

Further Help

For further information on this, please contact
Scott Barthelmy (for GCN issues),
or see the
Suzaku-WAM (Japan site), and
SUZAKU (NASA site), and
these GCN web pages, and


All past notices and lightcurves are archived at: GCN/SUZAKU Lightcurve table.
The Suzaku lightcurve website is: at.


These SUZAKU_LC notices are also distributed as part of the IPN_RAW notice type.
But in that stream, the actual lightcurves themselves are not available in the "push" mechanism,
only the "pull" mechanism from the IPN_RAW archive page.

E-mail Examples

Examples of the SUZAKU_LC Notice type of the e-mail formats are shown below.
The "/////" divider bars are NOT part of the messages.

Do not take the actual values shown in these examples as real events.
While based on flight data from the mission,
they have been adjusted to provide a broader representation
of the various combinations of fields and value ranges.

For those sites/people that use demons and/or incoming e-mail filters,
the "Subject" lines for the all notice types are constant.
The subject-line strings are (respectively):

/////////////////////////e-mail format/////////////////////////////////////////
NOTICE_DATE:   Sat 12 Jan 13 18:46:11 UT
TRIGGER_NUM:   1630306871
TRIGGER_DATE:  16303 TJD;    11 DOY;   13/01/11
TRIGGER_TIME:  6871.05 SOD {01:54:31.05} UT
LC_URL:        suzaku_lc_130111_06871.gif
COMMENTS:      SUZAKU WAM Lightcurve.
COMMENTS:      This event came from an on-board trigger.
The base for the given UL is "http://gcn.gsfc.nasa.gov/gcn/notices_suz/" .
e.g.:  "http://gcn.gsfc.nasa.gov/gcn/notices_suz/suzaku_lc_130111_06871.gif".
The extension (".gif") can also be replaced with ".txt", ".jpeg", ".ps", & ".pdf".

Cell/Pager Examples

Examples of the (regular) cell/pager formats are shown below.
There are no "Subject" lines for these e-mails sent to the cell/pager companies
because the Subject line would use up valuable character counts
from the maximum displayable for the body of the message.

/////////////////////////Cell/Pager format////////////////////////////////////////
TRIGGER_DATE: 13/01/11
TIME: 01:54:31.05 UT
An on-board trigger.

Short-form Cell/Pager Examples

Examples of the short-form cell/pager format are shown below.
There are no "Subject" lines for these e-mails sent to the cell/pager companies,
because the Subject-line would use up valuable character counts from the maximum
displayable for the body of the message. And it was the very limited
display character count of some companies that motivated the short-form cell/pager
method in the first place.

/////////////////////////Short-Cell/Pager format////////////////////////////////////
DATE: 13/01/11

Subject-only Examples

/////////////////////////Subject-only format////////////////////////////////////
SUZAKU_LIGHTCURVE D=13/01/11 T=01:54:31.05

Return to GCN/TAN homepage.
This file was last modified on 31-Mar-16.