Scott Barthelmy    Dec 1994
                       (revised 25 Jan 00)

GCN OPS NOTE(19Feb12):  This page is very old and contains only messages
related to the BACODINE/GRO-BATSE era.  For descriptions of the content and
format of more recent full-format email notices, please see the individual
mission/instrument-based web pages.

This document describes the contents and format of the e-mail messages
sent to those groups in the GCN system requesting the e-mail method.
The body of the e-mail is a little over 25 lines long (actually it varies
a few lines depending on the number of "COMMENT" fields at the end
of the e-mail.  There are many fields because this is the superset of all
the requirements by the various follow-up and heads-up operations.
The format is of the form "TOKEN: value(s)" on each line (see below).
This format is a reasonable compromise between human readable and
machine readable/parsable formats.


NOTICE_DATE:  Sun 28 Apr 96 13:12:38 UT
NOTICE_TYPE:  Original
GRB_RA:       303.96d {+20h 15m 51s} (J2000),
              303.93d {+20h 15m 43s} (current),
              303.53d {+20h 14m 07s} (1950)
GRB_DEC:      +41.80d {+41d 48' 05"} (J2000),
              +41.79d {+41d 47' 24"} (current),
              +41.65d {+41d 38' 48"} (1950)
GRB_ERROR:    tbd [deg radius]
GRB_INTEN:    613 [cnts]    Peak=613 [cnts/sec]
GRB_TIME:     47552.20 SOD {13:12:32.20} UT
GRB_DATE:     10201 TJD;   119 DOY;   96/04/28
GRB_SC_AZ:    341.70 [deg]                        {XScan=-11.38}
GRB_SC_EL:     51.05 [deg]  {Zenith_angle=38.95}  {Scan=37.50}
SC_X_RA:        9.31 [deg] (J2000)
SC_X_DEC:      29.20 [deg]
SC_Z_RA:      251.97 [deg]
SC_Z_DEC:      39.39 [deg]
SUN_POSTN:     36.14d {+02h 24m 34s}  +14.34d {+14d 20' 37"}
SUN_DIST:      82.11 [deg]
MOON_POSTN:   158.72d {+10h 34m 53s}   +5.37d {+05d 22' 14"}
MOON_DIST:    123.18 [deg]
COMMENTS:     Definite GRB
COMMENTS:     In COMPTEL FOV. Possible COMPTEL location to follow.


NOTICE_DATE:  Sun 28 Apr 96 13:31:44 UT
GRB_RA:       301.93d {+20h 07m 44s} (J2000),
              301.90d {+20h 07m 36s} (current),
              301.47d {+20h 05m 53s} (1950)
GRB_DEC:      +36.96d {+36d 57' 39"} (J2000),
              +36.95d {+36d 57' 00"} (current),
              +36.81d {+36d 48' 52"} (1950)
GRB_ERROR:    tbd [deg radius]
GRB_INTEN:    4512 [cnts]    Peak=4512 [cnts/sec]
GRB_TIME:     47552.20 SOD {13:12:32.20} UT
GRB_DATE:     10201 TJD;   119 DOY;   96/04/28
GRB_SC_AZ:    333.57 [deg]                        {XScan=-16.23}
GRB_SC_EL:     51.09 [deg]  {Zenith_angle=38.91}  {Scan=35.86}
SC_X_RA:        9.25 [deg] (J2000)
SC_X_DEC:      29.22 [deg]
SC_Z_RA:      251.88 [deg]
SC_Z_DEC:      39.41 [deg]
SUN_POSTN:     36.14d {+02h 24m 34s}  +14.34d {+14d 20' 37"}
SUN_DIST:      84.74 [deg]
MOON_POSTN:   158.72d {+10h 34m 53s}   +5.37d {+05d 22' 14"}
MOON_DIST:    125.50 [deg]
COMMENTS:     MAXBC Determination

MAXC1/BC Values:
C1:    28   -1   63    3    4   -3   14    1 
BC:   150   15  229   25   23    6   70    7 


1) The Subject_line will contain the standard string:

2) The From_line will be from "vxw@capella2.gsfc.nasa.gov (Bacodine)".
(For reasons of software development and access permissions, we had to create
a pseudo-person, "vxw", which stands for VX-Works, the company that makes
the operating system and cross-compiler for the single-board computers
that we are using to do most of the telemetry data crunching.)

3)  The body of the e-mail will contain:
    b)  The date/timestamp of this message (when the burst was calculated
        and this e-mail was sent): YY/MM/DD HH:MM:SS.ss UT
        It uses the capella2 computer system clock to generate this UT time.
    c)  Notice type:
        Original:   The first notification (using only the 1st 1-2sec of data),
        Final:      The final location notification.  This type is sent out
                    32sec after the start of the burst.
        MAXBC:      The MAXimum Burst Channels notification (using the max
                    count rates (64msec-sampling) scanned from T+0 to T+10min).
        LOCBURST:   The location using the MSFC Locburst algorithm.
        The "Final" type is particularly suitable for sites that have
        substantial response time (humans in the loop).  It is also useful
        because the fluence and peak intensity are reported and these are used
        to gauge the magnitude (importantce) of the burst.
        The "MAXBC" type is given for the MAXBC notices.
        The "LOCBURST" type has the smallest location uncertainty.
    d)  The Trigger Number:  This is a number assigned by the on-board BATSE
        flight software.  It sequentially and uniquely identifies each trigger.
    e)  The GRB numbers:
        RA  in decimal degrees; xxx.xx    {0.00  to  359.99}; in all 3 epochs.
        Dec in decimal degrees; +/-xx.xx  {-90.00  to  +90.00}; in all 3 epochs.
        The RA= HHh MMm SSs  Dec= DDd MM' SS" format is included as well,
        so that humans need not repeat a tedious calculation.
        I realize that 0.65 degrees seems pretty insignificant compared to the
        position uncertainties, but several people have expressed the desire
        and it only takes a milli-sec to calculate.
        Burst Error: This is a rough approximation to the position uncertainty.
            It is the radius of the approx 1-sigma circular error box.
            This number is approximate because, while the statistical
            uncertainty is easily calculable, the systematic uncertainty
            is not well determined.  This GRB_ERROR should be used as only a
            guideline in making decisions about follow-up observations,
            ie how well matched is the burst error circle to your FOV.
        Burst Intensity: A of measure of the burst intensity.  An approximation
            to the plane-wave intensity [cnts] integrated over the first
            1.024sec or 2.048sec of telemetry during the burst.
        UT Timestamp of the burst; SSSSS.ss {0.00 to 86399.99 sec-of-day};
            the BATSE on-board trigger start time.
        Date:  It includes 3 forms of specifying the date:
            a) The BATSE GRO SC way: Truncated Julian Day {9200 to 12000 days}
            which is Julian Day - 2440000.5 days,
            b) The Day-of-Year: {1 to 366},
            c) The Calendar date: YY/MM/DD {YY= 93,94,etc; MM=01-12; DD=01-31}
        Az  in decimal degrees; xxx.xx    {0.00  to  359.99}.
        El  in decimal degrees; +/-xx.xx  {-90.00  to  +90.00}.
            The burst position in GRO-spacecraft azimuth & elevation coords.
            There is a subfield on the Elevation line that gives Zenith angle.
            There are subfields on the Az & El lines which give the GRO-OSSE
            instrument Cross-scan & Scan angles.
    f)  Spacecraft Orientation:  These four fields list the RA,Dec directions
        for the positive X- & Z-axes of the spacecraft (epoch J2000).
        These fields are useful to the COMPTEL, EGRET, and OSSE recipients.
    g)  Sun & Moon Positions: There are four fields which give the RA,Dec
        locations (current epoch) of the Sun & the Moon and their angular
        distance from the burst location (in decimal degrees).  The Sun & Moon
        locations are also given in HMS,d'" notation as well.
        The Sun position is accurate to +-0.01 deg.
        The Moon location is accurate to +-1 deg.
        These fields are a convenience to the human recipients who are planning
        follow-up observations.
    h) Program Version: The version stamp for the program that generated
       these coordinates: "3.45".  This will be a way, albeit subtle & cryptic,
       to let people know when the software has changed.  Actually, it lets me
       keep track of what version of the software sent out a particular
    i) Program Level: The program coords calculation highest active level.
       A number between 1 through 3.
       3=scattering_correction plus minimize_looping.
    j) Comment:  A phrase which states whether this is a "Definite GRB",
       a "Test Burst", "Suspected Solar Flare", "Suspected Non-GRB Trigger", etc.
       Note that MAXBC notice can NOT have this trigger type identification,
       because there is insufficient information (countrates) available
       to make this determination (like for the Original/Final/LOCBURST).
       There can be additional "comment" lines:
       "In the COMPTEL FOV.  Possible COMPTEL position to follow",
       "Trigger direction is towards the Earth",
       "MAXBC Determination",
       "LOCBURST Determination".
    k) MAXC1/BC values:
       The MAXBC Notices have 16 numbers at the bottom of the Notice.
       These are the peak countrates in the 8 LADs in the 64-msec sampling
       rate encountered over the 0 to 10 minutes after the initial trigger
       in two energy bands: the C1 band (20-50 keV) and the so called
       "burst channels" band, which is most of the time set to be the sum
       of the C2 band (50-100) and the C3 band (100-300).  The "burst channels"
       are those used in the 3 trigger time scales (64, 256, & 1024 msec).
       The "burst channels" can be set to any combination of the four channels:
       C1, C2, C3, and C4 (note C4 is E > 300 keV).