TO:  All GCN Notice recipient sites                    29 Jun 06
RE:  A new Swift Notice type

INTRO / SUMMARY / ACTION_ITEM:
The Swift-UVOT team has created a new notice type.
You need to request it if you want to receive this new type.

NEW TYPE:
The new Swift-UVOT notice is called the UVOT_Position_Nack.
It is the opposite of the current UVOT_Position Notice.
So, like the BAT and XRT position notices which each have
an "ack" and a "nack" version, now all 3 instruments on Swift
have ack & nack forms of their position deteminations.

TYPICAL SEQUENCE:
Unlike BAT and XRT which have on-board determinations
of the positions (ack & nack), the large number of sources
in a typical UVOT image prevents on-board determinination.
Hense, the analysis is done on the ground (within ~15-60 minutes
after BAT trigger).  A combination of automated pipeline processing
and human-inspection are made on the UVOT images to determine
if there is a new source (ie the burst afterglow counterpart)
in any of those images.
If there is a new source, then an UVOT_Position notice
is generated and submitted to GCN for automated distribution
to those sites that have elected to receive that type.
Else if a new source is not detected, then a UVOT_Position_Nack
is submitted and distributed (also if sites have elected
to receive the nack-form).

WEB SITE:
This information is also explained (along with all the other Swift
Notice types) on the GCN website page:
   http://gcn.gsfc.nasa.gov/gcn/swift.html

ACTION ITEM:
Those sites who want to receive this UVOT_Pos_Nack Notice type
should send email (just forward this email to scott@milkyway.gsfc.nasa.gov)
with a statement to that effect.
Please also note that this is an opportunity to request any other changes
to your configuration (eg you want the UVOT_Pos (ack-form),
or other notice type dis/enables, address changes, etc).


EXAMPLE OF THE NEW NOTICE TYPE (IN FULL-FORMAT EMAIL FORM):

Subject: GCN/SWIFT_UVOT_POSITION_NACK

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 28 Jun 06 14:39:21 UT
NOTICE_TYPE:     Swift-UVOT Nack-Position
TRIGGER_NUM:     100081,   Seg_Num: 2
REGION_RA:        88.4206d {+05h 53m 40.9s} (J2000),
                  88.4755d {+05h 53m 54.1s} (current),
                  87.9500d {+05h 51m 47.9s} (1950)
REGION_DEC:      -31.4042d {-31d 24' 15.1"} (J2000),
                 -31.4033d {-31d 24' 11.9"} (current),
                 -31.4130d {-31d 24' 46.8"} (1950)
REGION_ERROR:    180.0 [arcsec search radius]
REGION_SOURCE:   BAT location
MAG_LIMIT:       19.51 [mag]   5.00 [sigma]
FILTER:          4, UVM2
IMG_START_DATE:  13674 TJD;   -61 DOY;   06/01/-61
IMG_START_TIME:  3373.78 SOD {00:56:13.78} UT,   3373.8 [sec] since BAT Trigger Time
SUN_POSTN:        97.37d {+06h 29m 28s}  +23.27d {+23d 15' 55"}
SUN_DIST:         55.33 [deg]   Sun_angle= 0.6 [hr] (West of Sun)
MOON_POSTN:      134.60d {+08h 58m 23s}  +20.96d {+20d 57' 26"}
MOON_DIST:        68.52 [deg]
MOON_ILLUM:      9 [%]
GAL_COORDS:      236.86,-25.28 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       87.66,-54.83 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-UVOT Nack Position.  
COMMENTS:        A point_source was not found.  
COMMENTS:        The search was complicated by a nearby 7th mag star. 


Sincerely,
Scott