This page has been changed from that for the original O1 and O2 methods and formats to the new O3 methods and formats.
The LVC has changed some things, and so GCN has followed.

GCN/LVC Notices

TABLE OF CONTENTS:

  1. Introduction
  2. Notice types, Content, and Purpose
  3. Time_delays
  4. Sequence of Activities
  5. Retractions
  6. Formats
  7. Filtering
  8. Location Error
  9. Test Notices
  10. Observing Strategy
  11. Recognition
  12. Further Help
  13. E-mail Examples
  14. Cell/Pager Examples
  15. Short-form Cell/Pager Examples
  16. Subject-only Cell/Pager Examples
  17. VOEvent Example
  18. LVC Counterpart Notice Examples

Introduction

The GCN system has been modified to incorporate the distribution of G-W events (aka triggers)
by the LIGO and Virgo instruments.

About 2 times a month, the LVC real-time pipelines will trigger (when there is suffcient enough signal)
and produce a series of LVC Notices (Preliminary, Initial, and Update).
All 3 Notice types will have maps giving the location probability of the event on the sky.

There are two LVC pipelines: Compact Binary Coalescence (CBC) and Burst (outbursts of excess power in the detectors).

Like all the other sources of GRB/transient information within the GCN system,
users can elect to receive each of these LVC Notice types. LVC is now in a public phase of operations
and all Notices will be distributed to those sites requesting the LVC Notice types.

The LVC notices are archived at Table of LVC Events.
And the Circulars are archived at Circulars (includes LVC-related Circs).

Notice Types, Content, and Purpose

There are 5 (4 regular + 1 counterpart) GCN/LVC Notice types.
They are:

1) Preliminary Notice starts the sequence of notices.
It contains the Trigger number, the type of trigger (CBC or Burst), the trigger date and time,
the parameters that characterise the trigger (and for Group=Burst: Fluence, Duration, and CentralFrequency)
as determined by the real-time LSC processing pipeline, the false alarm rate for a trigger of the same parameter values,
and a set of sky localization maps in FITS and PNG formats.
There is also a Retraction form of the Preliminary Notice. Retractions can be issued at any step
in the sequence of procesing and sending out alerts.
These Notices come in two substreams: S-series and MS-series. The S-series are real triggers and the MS-series
are Mock data challenge Superevent fake triggers. For real triggers (S-series), there will typically be 1 Preliminary notices issued
(occaisionally a second Preliminary is possible).
The first Preliminary Notice will be ~1-4 minute after the event.
There is no human-in-the-loop involvement in the processing of the real-time G-W data.

2) Initial Notice A couple minutes to hours(tbr) later, the Initial Notice is produced and distributed.
All the information and values are the same as the Prelimianry Notice, but including a location probability skymap
has been calculated and added. This map gives the probability that the GW event occured a given point on the sky
The Initial Notice contains a URL pointing to the map file (in HEALPIX FITS format).
This file can be retrieved from the LVC site, and then interrogated to guide your follow-up observations.
There is also a Retraction form of the Initial Notice. Retractions can be issued at any step in the processing.
These come in two substreams: S-series and MS-series. The S are real triggers, and the MS are Mock data challenge Superevent fake triggers.
There will be 1 to a few Initial Notices 1-6(tbr) hours after the event. They contain skymaps from more detailed/offline processing.
There is human-in-the-loop involvement reviewing the pipeline analysis to better determine if the trigger is a real G-W event.
This can result in a retraction of the triger (it is not a real G-W event), or an adjustment to the findings that go into the Initial Notices.

3) Update Notice In several to ~24 hours later, the Updated Notice will be produced and distributed.
And now the location probability map has been refined by doing the parameter estimation pipeline analysis.
The notice contains another url used to retrieve the refined map. It is also possible that the trigger will be retracted.
Retractions can be issued at any step in the processing.
An example of an Update Retraction is shown below
for the full-format email method.
Like the Preliminary and Initial, the Updates come in two substreams: S-series and MS-series.
There will be 1 to a few Update Notices issued from several to 24 hours after the event. They contain skymaps
from even more detailed and offline processing.
There is human-in-the-loop involvement reviewing the pipeline analysis, and adjusting the findings that go into the Update Notices.

4) Test Notice
The Test Notice is identical in format and content to the Initial/Update Notice types.
The Test notices are issued every ~4 hours covering a grid of locations roughly equally spaced
on the northern and southern hemispheres. These allow people/teams/instruments to practice operations.
Additionally for testing purposes, there will be 'role="test"' versions
of the Prelim/Initial/Update notices in the VOEvent XML format
intersperced amongst the 'role="observe"' notices.

5) LVC Counterpart Notice
This notice is produced by a follow-up observer that has identified a potential EM candidate
for the GW event. These contain the RA,Dec location of the candidate, the GW trigger ID,
the identity of the observer and the instrument/telescope used to make the follow-up observation,
the waveband of the observation, the duration, and the measured intenisty/flux/magnitude.
This LVC Counterpart notice is identical in format and content as the regular Counterpart notice;
but an LVC version was created to be used for LVC follow-ups during the proprietary period of LVC start-up operations.

S-series and MS-series Triggers

The PRELIMINARY, INITIAL, and UPDATE LVC Notices come in two sub-streams: The S-series and MS-series.
The S-series are the real triggers from the real-time low-latency pipelines looking for GW events.
The MS-series are the Mock data challenge Superevent fake triggers generated by an off-line program
that uses archival data that has been scrambled to have not science content whatsoever.
The purpose of the MS-series is to allow the recipient to do testing. The MS-series are a different form
of testing notices from the LVC_TEST notice that SCN generates.
The S-series real tiggers occur about 2 per month (the prediction);
the MS-series come every 15 minutes (they are almost always PRELIMINARY; and
the LVC_TEST come every 3.7 hours.
The MS-series are generatd by LVC; and the LVC_TEST are generated by GCN.

Filtering S- vs MS-series Notices: Special filtering has been added to GCN to allow recipients
to select which substreams they want to receiver. In the recipient's configuration is a new field: "LVC_Enabled".
LVC_Enabled is a bitmask which takes on values of 0x200 for the S-series, 0x2000 for the MS-series,
Because it is a specialied filter function, it does not appear on the Configuration webform page.
If a recipient does not want to receive this MS-series, just tell me, and I will add it to your configuration.
So LVC_Enable = 0x2200 means get both series, =0x200 means get only the S-series, and =0x2000 mean get only the MS-series.

Time Delays

The automated LVC pipelines will generate alert and position notifications in real time.
(In addition, human-involved analyses of the data may sometimes result
in a revised position within a few to 24 hours after the trigger.)
The timescales and localization precisions of the 3 Notice types are as follows:

                 TIME SINCE    
TYPE             TRIGGER(tbr)  COMMENTS
=========        ============  ==========================================================================
LVC_PRELIMINARY  1-4 min       First Notice, Timestamp Alert, automated processing, with SkyMap available
LVC_INITIAL      1-6 hr        Better SkyMap now available (human-involved procesing)
LVC_UPDATE       ~1 day        Ultimate refined skymap (more detailed off-line processing)
=========        ============  ==========================================================================

Sequence of Activities

The sequence of activities for a typical burst follows:

For real triggers (S-series), there will typically be 1 (possibly 2) Preliminary notices issued.
The first will be 1-4 minutes after the event and contain date, time, param value, and a sky localization map.

There will be 1 to a few Initial Notices 1-6 hours after the event. They contain skymaps from more detailed/offline processing.

There will be 1 to a few Update Notices several to 24(tbr) hours after the event. They contain skymaps from even more detailed/offline processing.

There is a Sequence number associated with each series of Prelim/Initial/Update notices for a given event. It spans all 3 subtypes.
A sequence to Notices might look like:
     1-Preliminary,
     2-Preliminary,
     3-Initial,
     4-Update,
Sometimes there will be missing sequnce numbers in those notices distributed,
because these "missing" notices have the "Internal" flag set to "1". Which means they were distributed to LVC_Team internally;
not to the public.

Anytime during this sequence a Retraction notice can be issued.
It will be of P/I/U type of the last one issued prior to this retraction
(eg Preliminar-retraction, Initial-Retraction, or Update-Retraction).

The LVC-to-GCN-to-World Procedure:
Notices: GCN receives the LVC messages directly from the LVC real-time processing pipeline,
converts the LVC VOEvent messages into all the standard GCN_Notice formats, and
distributes them to the sites using the usual distribution methods and filtering.
The total amount of time from the LVC pipeline to the output port on the GCN system is in the less than 1 sec.
Circulars: For each trigger, members from the LVC team respond (human-in-the-Loop)
to (a) determine if this trigger is real or not, (b) to provide any supporting information,
and (c) issue the circular 2 to 24 hours after the trigger.
All the LVC-related Circulars are stored at Circular.

Follow-up observations: Using the information in the LVC Notices, follow-up observers
start making observations of the skymap regions. Their findings (candidates and upper limits)
can and should be published byt submitting in the LVC_COUNTERPART notices and LVC Circulars.

lvc notices and circ time sequence and ranges
NOTE: This figure needs adjustment. The times whenthe PRELIMINARY and INITIAL occur needs to be moved and stretched to the right.

Retractions

In the notice sequence of Prelminary, Initial, and Update, a retraction will be issued
if the ongoing processing (automated and human-in-the-loop) determined that the trigger
is no longer astrophysical in origin.

Formats

EMAIL-BASED: Samples of the E-mail, Cell/Pager, Short-form Cell/Pager, & Subject-only
distribution methods of the 5 GCN/LVC Notice types are included below.
The format is very similar to the other spacecraft-instrument sources
of GRB locations -- the GCN-standard "TOKEN: value" format.

SOCKET-BASED: The 160-byte binary 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 (Types 150-152).
This document also has explanations of the various fields in the packet
(their content, values, and implications for use).
and those same fields are appear in the email-based formats.
(Therefore, it is useful for email/cell/pager recipients to read the
socket packet definition document to understand the contents of the email/cell/pager/VOEvent notifications are.)

NUM  TYPE             VOEVENT  SOCKET   EMAIL  EMAIL  EMAIL EMAIL  EMAIL  EMAIL  EMAIL  PAGER/CELL
                                        w/Txt  w/PS   w/GIF w/JPEG w/PDF  w/FITS        (all 4 variants)

150  Preliminary      Y        P        B+U                               n/a           B
151  Initial          Y        P        B+U                               n/a           B
152  Update           Y        P        B+U                               n/a           B
153  Test             Y        P        B+U                                             B
154  Counterpart      Y        P        B                                               B

where:
Y = Available in XML VOEvent format for XML_Sockets and VOEvent server sockets.
P = Packet (the GCN-standard 160-byte socket packet format).
B = Body of email (the GCN-standard "TOKEN: value" format)
U = URL (the URL is contained in the packet and the body of the email)
A = Attachment (the actual data product is optionally attached to the email)

Filtering

Sites can elect to receive each of the 5 LVC Notice types on a type-by-type basis.
There is a separate dis/enable bit for each type.
See filtering to see which of the many other filter functions are applicable.
This filtering applies to all the existing distribution methods/media.

See the description of the specialized filtering for the S- and MS-series Notices above.

Location Errors

The uncertainty in the location will depend on:
(a) the number of GW detectors that contributed to the trigger (2 or 3),
(b) the masses of the compact objects involved, and
(c) the duration of the GW event, and ????.
The regions on the sky are banana-shaped regions.
The typical sizes of these regions are:
10x90 deg for 2-detector triggers, and there will be 2 such regions;
10 deg diameter regions for 3-detector triggers, and there will be only 1 region.

Test Notices

To allow sites to "practice" on LVC Notices, there is LVC Test Notice.
It mimics the LVC_INITIAL/UPDATE Notice types (in all the socket packet, VOEvent,
email, and cell/pager formats).
Sites can elect to receive this Test Notice.
These Test Notices are issued every ~4 hours.
The the central positions of the banana-shaped location regions in the SkyMaps
rotate through a grid on the Northern & Southern celestial skies.

Observing Strategy

These GW detectors are essentially omni-directional. As such, the detections
will be from sources uniformly distributed across the 4pi of the sky.
Since very few follow-up instruments can cover these large patches on the sky (~10x60deg),
a common follow-up approach will be to observe the galaxies that are located
in the regions of high probability.

Recognition

During the Proprietery phase of LVC operations, recognition, and publication procedures
are covered in the MoU that every follow-up observer/team has signed with LVC.
And during the following Public phase, sites are encouraged to acknowledge LVC and GCN in their publications
based on follow-up observations using these GCN/LVC locations.

Further Help

For further information on this, please contact
Scott Barthelmy (for GCN issues),
or see the LVC LV-EM Techinical Information,
or see the LVC LV-EM Follow-Up Tutorial,
and
these GCN web pages, and
GCN/Swift GRB table.


E-mail Examples

Examples of the 5 Notice types of the e-mail formats are shown below.
The "/////" divider bars are NOT part of the messages.

Note that the usual fields (SUN_POSTN, SUN_DIST, MOON_POSTN, MOON_DIST, MOON_ILLUM,
GAL_CCORDS, and ECL_COORDS) that are in all the GCN e-mail notice formats are not present
in the LVC PRELIMINARY, INITIAL, UPDATE, and TEST notices, because these are meaningless quantities
for an event, that at this stage, has an error region covering 100's of degrees.
The LVC_COUNTERPART notice does have the observer-support fields, because at this stage
of the observations sequence, the error boxes are now down to less than one degree.

Do not take the actual values shown in these examples as real GW events.
While based on data from a run back in 2010, they are not real triggers.

For those sites/people that use demons and/or incoming e-mail filters (e.g. procmail),
the "Subject" lines for the all notice types are constant.
The subject-line strings are (respectively):
The 'raw' versions:
GCN/LVC_PRELIMINARY
GCN/LVC_INITIAL
GCN/LVC_UPDATE
GCN/LVC_TEST
GCN/LVC_COUNTERPART

//////////////////////// Preliminary e-mail format ////////////////////////////////
TITLE:            GCN/LVC NOTICE
NOTICE_DATE:      Wed 04 Jan 17 22:00:25 UT
NOTICE_TYPE:      LVC Preliminary
TRIGGER_NUM:      S123456aa
TRIGGER_DATE:     17757 TJD;     4 DOY;   2017/01/04 (yyyy/mm/dd)
TRIGGER_TIME:     77450.281284 SOD {21:30:50.281284} UT
GROUP_TYPE:       1 = CBC
SEARCH_TYPE:      6 = MockDataChallenge
PIPELINE_TYPE:    4 = GSTLAL
FAR:              9.112e-14 [Hz]  (one per 127024138.3 days)
TRIGGER_ID:       0x3
MISC:             0x1300003
SKYMAP_URL:       https://gracedb.ligo.org/api/events/S123456aa/files/bayestar.fits.gz
SKYMAP_BASIC_URL: https://gracedb.ligo.org/apibasic/events/S123456aa/files/bayestar.fits.gz
EVENT_URL:        https://gracedb.ligo.org/events/S123456aa
COMMENTS:         LVC Trigger Alert with Skymap.
COMMENTS:         LVC Trigger Alert.
COMMENTS:         LIGO-Hanford Observatory contributed to this candidate event.
COMMENTS:         LIGO-Livingston Observatory contributed to this candidate event.
COMMENTS:         This is an M-series trigger (M is for Mock Data Challenge).
//////////////////////// Initial e-mail format ////////////////////////////////////
TITLE:            GCN/LVC NOTICE
NOTICE_DATE:      Wed 04 Jan 17 22:00:33 UT
NOTICE_TYPE:      LVC Initial Skymap
TRIGGER_NUM:      S123456aa
TRIGGER_DATE:     17757 TJD;     4 DOY;   2017/01/04 (yyyy/mm/dd)
TRIGGER_TIME:     77450.281284 SOD {21:30:50.281284} UT
GROUP_TYPE:       1 = CBC
SEARCH_TYPE:      6 = MockDataChallenge
PIPELINE_TYPE:    4 = GSTLAL
FAR:              9.112e-14 [Hz]  (one per 127024138.3 days)
PROB_NS:          100.00 [%]
PROB_REMNANT:     100.00 [%]
TRIGGER_ID:       0x3
MISC:             0x2300003
SKYMAP_URL:       https://gracedb.ligo.org/api/events/S123456aa/files/bayestar.fits.gz
SKYMAP_BASIC_URL: https://gracedb.ligo.org/apibasic/events/S123456aa/files/bayestar.fits.gz
EVENT_URL:        https://gracedb.ligo.org/events/S123456aa
COMMENTS:         LVC Initial Skymap -- a location probability map.
COMMENTS:         LIGO-Hanford Observatory contributed to this candidate event.
COMMENTS:         LIGO-Livingston Observatory contributed to this candidate event.
COMMENTS:         This is an M-series trigger (M is for Mock Data Challenge).
//////////////////////// Update e-mail format /////////////////////////////////////
TITLE:            GCN/LVC NOTICE
NOTICE_DATE:      Wed 04 Jan 17 22:00:48 UT
NOTICE_TYPE:      LVC Update Skymap
TRIGGER_NUM:      S123456aa
TRIGGER_DATE:     17757 TJD;     4 DOY;   2017/01/04 (yyyy/mm/dd)
TRIGGER_TIME:     77450.281284 SOD {21:30:50.281284} UT
GROUP_TYPE:       1 = CBC
SEARCH_TYPE:      6 = MockDataChallenge
PIPELINE_TYPE:    4 = GSTLAL      
FAR:              9.112e-14 [Hz]  (one per 127024138.3 days)
PROB_NS:          100.00 [%] 
PROB_REMNANT:     100.00 [%]  
TRIGGER_ID:       0x3 
MISC:             0x3300003
SKYMAP_URL:       https://gracedb.ligo.org/api/events/S123456aa/files/lalinference.fits.gz
SKYMAP_BASIC_URL: https://gracedb.ligo.org/apibasic/events/S123456aa/files/lalinference.fits.gz
EVENT_URL:        https://gracedb.ligo.org/events/S123456aa 
COMMENTS:         LVC Updated Skymap -- a location probability map.
COMMENTS:         LIGO-Hanford Observatory contributed to this candidate event.
COMMENTS:         LIGO-Livingston Observatory contributed to this candidate event.
COMMENTS:         This is an M-series trigger (M is for Mock Data Challenge).
//////////////////////// RETRACTION Update e-mail format //////////////////////////
TITLE:            GCN/LVC NOTICE
NOTICE_DATE:      Wed 04 Jan 17 22:00:48 UT
NOTICE_TYPE:      RETRACTION LVC Update Skymap
TRIGGER_NUM:      S123456aa
TRIGGER_DATE:     17757 TJD;     4 DOY;   2017/01/04 (yyyy/mm/dd)
TRIGGER_TIME:     77450.281284 SOD {21:30:50.281284} UT
GROUP_TYPE:       1 = CBC
SEARCH_TYPE:      6 = MockDataChallenge
PIPELINE_TYPE:    4 = GSTLAL      
FAR:              9.112e-14 [Hz]  (one per 127024138.3 days)
PROB_NS:          100.00 [%] 
PROB_REMNANT:     100.00 [%]  
TRIGGER_ID:       0x3 
MISC:             0x3300003
SKYMAP_URL:       https://gracedb.ligo.org/api/events/S123456aa/files/lalinference.fits.gz
SKYMAP_BASIC_URL: https://gracedb.ligo.org/apibasic/events/S123456aa/files/lalinference.fits.gz
EVENT_URL:        https://gracedb.ligo.org/events/S123456aa 
COMMENTS:         LVC Updated Skymap -- a location probability map.
COMMENTS:         LIGO-Hanford Observatory contributed to this candidate event.
COMMENTS:         LIGO-Livingston Observatory contributed to this candidate event.
COMMENTS:         This is an M-series trigger (M is for Mock Data Challenge).
//////////////////////// Test e-mail format ///////////////////////////////////////
TITLE:            GCN/LVC NOTICE
NOTICE_DATE:      Wed 04 Jan 17 02:35:20 UT
NOTICE_TYPE:      LVC Test Skymap
TRIGGER_NUM:      T23456
TRIGGER_DATE:     17757 TJD;     4 DOY;   2017/01/04 (yy/mm/dd)
TRIGGER_TIME:     9309.123456 SOD {02:35:09.123456} UT
GROUP_TYPE:       1 = CBC
SEARCH_TYPE:      2 = LowMass
PIPELINE_TYPE:    4 = GSTLAL
FAR:              1.200e-05 [Hz]  (one per 1.0 days)
PROB_NS:          0.00 [%]
PROB_REMNANT:     0.00 [%]
TRIGGER_ID:       0x0
MISC:             0x40200003
SKYMAP_URL:       https://gcn.gsfc.nasa.gov/gcn/notices_l/23456aa/files/skymap.fits
SKYMAP_BASIC_URL: https://gcn.gsfc.nasa.gov/gcn/notices_l/23456aa/files/skymap.fits
EVENT_URL:        https://gcn.gsfc.nasa.gov/gcn/notices_l/23456aa
COMMENTS:         LVC Test Skymap -- a test location probability map.
COMMENTS:         LIGO-Hanford Observatory contributed to this candidate event.
COMMENTS:         LIGO-Livingston Observatory contributed to this candidate event.
COMMENTS:
COMMENTS:         NOTE: This LVC TEST notice type is still in development stage -- the URLs are not valid.
//////////////////////// Counterpart e-mail format ////////////////////////////////
See at end of this webpage.
///////////////////////////////////////////////////////////////////////////////////

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.
RA,Dec values are in Current epoch.

///////////////////////// Preliminary Cell/Pager format ///////////////////////////
GCN/LVC Prelim
T=12:25:21.00 UT
TRIGGER_NUM=M169734
GROUP=CBC
FAR=3.773e-14 [Hz]
///////////////////////// Initial Cell/Pager format ///////////////////////////////
GCN/LVC Initial Event
T=12:25:21.00 UT
TRIGGER_NUM=M169734
GROUP=CBC
FAR=3.773e-14 [Hz]
///////////////////////// Update Cell/Pager format ////////////////////////////////
GCN/LVC Update Event
T=12:25:21.00 UT  
TRIGGER_NUM=M169734
GROUP=CBC
FAR=3.773e-14 [Hz]
///////////////////////// Test Cell/Pager format //////////////////////////////////
GCN/LVC Test Event
T=01:30:51.12 UT  
TRIGGER_NUM=M123456aa
GROUP=CBC
FAR=5.000e-15 [Hz]
///////////////////////// Counterpart Cell/Pager format ///////////////////////////
See at end of this webpage.
///////////////////////////////////////////////////////////////////////////////////

Short-form Cell/Pager Examples

Examples of the short-form pager format are shown below.
There are no "Subject" lines for these e-mails sent to the 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 pager method in the first place.
RA,Dec are in B1950 epoch.

///////////////////////// Preliminary Short-Cell/Pager format /////////////////////
LVC Prelim
T=12:25:21.00 UT
TRIG_NUM=M169734
///////////////////////// Initial Short-Cell/Pager format /////////////////////////
LVC Initial
T=12:25:21.00 UT
TRIG_NUM=M169734
///////////////////////// Update Short-Cell/Pager format //////////////////////////
LVC Update   
T=12:25:21.00 UT  
TRIG_NUM=M169734
///////////////////////// Test Short-Cell/Pager format ////////////////////////////
LVC Test   
T=01:30:51.12 UT  
TRIG_NUM=M123456
///////////////////////// Counterpart Short-Cell/Pager format /////////////////////
See at end of this webpage.
///////////////////////////////////////////////////////////////////////////////////


Subject-only Examples

Normally for GCN Notices, there are two variations of the Subject-only format:
decimal degrees (Current epoch), and
RA=hh:mm:ss Dec=DDdMMmSSs format (J2000 epoch).
But since the LVC Notices do not have a well located event position -- rather a large error region --
the TriggerTime was incorporated into the Subject-line in place of the RA,Dec.

///////////////////////// Prelminary Subject-only format //////////////////////////
LVC Prelim T=12:25:21.00 UT
///////////////////////// Initial Subject-only format /////////////////////////////
LVC Initial T=12:25:21.00
///////////////////////// Update Subject-only format //////////////////////////////
LVC Update T=12:25:21.00 UT
///////////////////////// Test Subject-only format ////////////////////////////////
LVC Test T=01:30:51.12 UT
///////////////////////// Counterpart Subject-only format /////////////////////////
See at end of this webpage.
///////////////////////////////////////////////////////////////////////////////////


VOEvent Notice Examples

Here are examples of the LVC Notices (VOEvent format).

//////////////////////// Preliminary voevent format ////////////////////////////////
<?xml version="1.0" ?> <voe:VOEvent xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:voe="http://www.ivoa.net/xml/VOEvent/v2.0" xsi:schemaLocation="http://www.ivoa.net/xml/VOEvent/v2.0 http://www.ivoa.net/xml/VOEvent/VOEvent-v2.0.xsd" version="2.0" role="observation" ivorn="ivo://gwnet/gcn_sender#S181201e-1-Preliminary"> <Who> <Date>2018-12-01T22:02:02</Date> <Author> <contactName>LIGO Scientific Collaboration and Virgo Collaboration</contactName> </Author> </Who> <What> <Param name="internal" dataType="int" value="1"> <Description>Indicates whether this event should be distributed to LSC/Virgo members only</Description> </Param> <Param name="Pkt_Ser_Num" dataType="string" value="1"/> <Param name="GraceID" dataType="string" value="S181201e" ucd="meta.id"> <Description>Identifier in GraceDB</Description> </Param> <Param name="AlertType" dataType="string" value="Preliminary" ucd="meta.version" unit=""> <Description>VOEvent alert type</Description> </Param> <Param name="Retraction" dataType="string" value="false" ucd="meta.code" unit=""> <Description>Set to true if the event is retracted.</Description> </Param> <Param name="HardwareInj" dataType="int" value="0" ucd="meta.number" unit=""> <Description>Indicates that this event is a hardware injection if 1, no if 0</Description> </Param> <Param name="Vetted" dataType="int" value="0" ucd="meta.number" unit=""> <Description>Indicates whether this candidate has undergone basic vetting by humans</Description> </Param> <Param name="OpenAlert" dataType="int" value="1" ucd="meta.number" unit=""> <Description>Indicates that this event is an open alert if 1, no if 0</Description> </Param> <Param name="EventPage" dataType="string" value="https://gracedb-playground.ligo.org/superevents/S181201e/view/" ucd="meta.ref.url"> <Description>Web page for evolving status of this GW candidate</Description> </Param> <Param name="Instruments" dataType="string" value="H1,L1" ucd="meta.code"> <Description>List of instruments used in analysis to identify this event</Description> </Param> <Param name="FAR" dataType="float" value="5.80161395192e-05" ucd="arith.rate;stat.falsealarm" unit="Hz"> <Description>False alarm rate for GW candidates with this strength or greater</Description> </Param> <Param name="Group" dataType="string" value="CBC" ucd="meta.code" unit=""> <Description>Data analysis working group</Description> </Param> <Param name="Pipeline" dataType="string" value="spiir" ucd="meta.code" unit=""> <Description>Low-latency data analysis pipeline</Description> </Param> <Param name="Search" dataType="string" value="LowMass" ucd="meta.code" unit=""> <Description>Specific low-latency search</Description> </Param> <Param name="ProbHasNS" dataType="float" value="1.0" ucd="stat.probability" unit=""> <Description>Probability that at least one object in the binary is less than 3 solar masses</Description> </Param> <Param name="ProbHasRemnant" dataType="float" value="1.0" ucd="stat.probability" unit=""> <Description>Probability that there is matter in the surroundings of the central object</Description> </Param> <Group type="GW_SKYMAP" name="bayestar"> <Param name="skymap_fits_shib" dataType="string" value="https://gracedb-playground.ligo.org/apiweb/superevents/S181201e/files/bayestar.fits.gz" ucd="meta.ref.url" unit=""> <Description>Sky Map FITS Shibboleth protected</Description> </Param> <Param name="skymap_fits_x509" dataType="string" value="https://gracedb-playground.ligo.org/api/superevents/S181201e/files/bayestar.fits.gz" ucd="meta.ref.url" unit=""> <Description>Sky Map FITS X509 protected</Description> </Param> <Param name="skymap_fits_basic" dataType="string" value="https://gracedb-playground.ligo.org/apibasic/superevents/S181201e/files/bayestar.fits.gz" ucd="meta.ref.url" unit=""> <Description>Sky Map FITS basic auth protected</Description> </Param> <Param name="skymap_png_shib" dataType="string" value="https://gracedb-playground.ligo.org/apiweb/superevents/S181201e/files/bayestar.png" ucd="meta.ref.url" unit=""> <Description>Sky Map image Shibboleth protected</Description> </Param> <Param name="skymap_png_x509" dataType="string" value="https://gracedb-playground.ligo.org/api/superevents/S181201e/files/bayestar.png" ucd="meta.ref.url" unit=""> <Description>Sky Map image X509 protected</Description> </Param> <Param name="skymap_png_basic" dataType="string" value="https://gracedb-playground.ligo.org/apibasic/superevents/S181201e/files/bayestar.png" ucd="meta.ref.url" unit=""> <Description>Sky Map image basic auth protected</Description> </Param> </Group> </What> <WhereWhen> <ObsDataLocation> <ObservatoryLocation id="LIGO Virgo"/> <ObservationLocation> <AstroCoordSystem id="UTC-FK5-GEO"/> <AstroCoords coord_system_id="UTC-FK5-GEO"> <Time> <TimeInstant> <ISOTime>2018-12-01T22:01:21.395020</ISOTime> </TimeInstant> </Time> </AstroCoords> </ObservationLocation> </ObsDataLocation> </WhereWhen> <How> <Description>Candidate gravitational wave event identified by low-latency analysis</Description> <Description>H1: LIGO Hanford 4 km gravitational wave detector</Description> <Description>L1: LIGO Livingston 4 km gravitational wave detector</Description> </How> <Description>Report of a candidate gravitational wave event</Description> </voe:VOEvent>

//////////////////////// Initial voevent format ////////////////////////////////////

//////////////////////// Update voevent format /////////////////////////////////////

LVC Counterpart Notice Example

Here is an example of the LVC Counterpart Notice (e_mail format).

//////////////////////// COUNTERPART e-mail format (optical) ///////////////////////
TITLE:          GCN/LVC_COUNTERPART POSITION NOTICE
NOTICE_DATE:    Wed 07 Oct 14 10:34:46 UT
NOTICE_TYPE:    Optical
TRIGGER_NUM:    123456aa
CNTRPART_RA:    123.4560d {+08h 13m 49.4s} (J2000),
                123.4588d {+08h 13m 50.1s} (current),
                122.8101d {+08h 11m 14.4s} (1950)
CNTRPART_DEC:    +1.2344d {+01d 14' 03.8"} (J2000),
                 +1.2337d {+01d 14' 01.4"} (current),
                 +1.3866d {+01d 23' 11.6"} (1950)
CNTRPART_ERROR: 599.8 [arcsec, radius]
GRB_DATE:       14015 TJD;   280 DOY;   06/10/07
GRB_TIME:       36488.81 SOD {10:08:08.81} UT
OBS_DATE:       14015 TJD;   280 DOY;   06/10/07
OBS_TIME:       36518.00 SOD {10:08:38.00} UT
OBS_DUR:        10.0 [sec]
MAG:            16.5 +/- 1.0
FILTER:         U
SEEING:         1.5 [arcsec]
TELESCOPE:      ROTSE
SUBMITOR:       Eli_Rykoff
SUN_POSTN:      202.82d {+13h 31m 16s}   -9.54d {-09d 32' 34"}
SUN_DIST:        79.72 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:     162.75d {+10h 51m 01s}   +8.81d {+08d 48' 28"}
MOON_DIST:       39.84 [deg]
MOON_ILLUM:     14 [%] 
GAL_COORDS:     221.51, 18.83 [deg] galactic lon,lat of the counterpart
ECL_COORDS:     125.46,-18.18 [deg] ecliptic lon,lat of the counterpart
COMMENTS:       LVC COUNTERPART Coordinates.
/////////////////////// COUNTERPART e-mail format (x-ray) //////////////////////////
TITLE:          GCN/LVC_COUNTERPART POSITION NOTICE
NOTICE_DATE:    Sat 19 Oct 14 15:13:35 UT
NOTICE_TYPE:    Other
TRIGGER_NUM:    20141
CNTRPART_RA:    296.1749d {+19h 44m 41.9s} (J2000),
                296.2818d {+19h 45m 07.6s} (current),
                295.6628d {+19h 42m 39.0s} (1950)
CNTRPART_DEC:   +27.2113d {+27d 12' 40.6"} (J2000),
                +27.2370d {+27d 14' 13.1"} (current),
                +27.0896d {+27d 05' 22.5"} (1950)
CNTRPART_ERROR: 2.5 [arcsec, radius]
GRB_DATE:       15357 TJD;   -935 DOY;   13/01/-935
GRB_TIME:       0.00 SOD {00:00:00.00} UT
OBS_DATE:       15357 TJD;   -935 DOY;   13/01/-935
OBS_TIME:       58744.0 SOD {16:19:04.00} UT
OBS_DUR:        1950.0 [sec]
INTENSITY:      0.00e+00 +/- 0.00e+00 [erg/cm2/sec]
ENERGY:         0.3-10 [keV]
TELESCOPE:      Swift-XRT
SUBMITTER:      Phil_Evans
SUN_POSTN:      204.48d {+13h 37m 56s}  -10.18d {-10d 11' 05"}
SUN_DIST:        96.22 [deg]   Sun_angle= -6.1 [hr] (East of Sun)
MOON_POSTN:      31.79d {+02h 07m 10s}  +13.12d {+13d 06' 56"}
MOON_DIST:       88.81 [deg]
MOON_ILLUM:     100 [%]
GAL_COORDS:      62.97,  1.50 [deg] galactic lon,lat of the counterpart
ECL_COORDS:     305.48, 47.48 [deg] ecliptic lon,lat of the counterpart
COMMENTS:       LVC COUNTERPART Coordinates.  
COMMENTS:       Swift is performing multiple tiled observations of this LVC trigger.
COMMENTS:       This object is uncatalogued.   
COMMENTS:       The INTENSITY is the OBSERVED flux.
COMMENTS:       See http://www.swift.ac.uk/xrt_products/TILED_TBD00003 for more details.
COMMENTS:       We cannot confirm whether this is the GRB, or serendipitous.
//////////////////////// Counterpart cell/pager format /////////////////////////////
GCN/COUNTERPART
Optical
RA=218.27d  DEC=+59.36d
ERR=0.5deg
TIME: 23:05:12.83 UT
MAG=16.5 +/- 1.0
FILTER=U
SEEING=1.5 [arcsec]
//////////////////////// Counterpart short cell/pager format ///////////////////////
GRB_COUNTERPART
Optical
RA=295.663 DEC=+27.089
//////////////////////// Counterpart Subject-only format ///////////////////////////
GRB_COUNTERPART Optical RA=+19h 42m 39.0s DEC=+27d 14' 13.1"
//////////////////////// Counterpart ?????? format /////////////////////////////////
[i need to fill in these examples!!!]
////////////////////////////////////////////////////////////////////////////////////


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This file was last modified on 01-Dec-18.