Filter out known Swift sources

[martinjohndyer]

From Slack:

Klaas Wiersema
I saw that the other day GOTO observed Swift trigger 888312, which was a trigger on a known source (a HMXB in outburst). It might be useful to filter those triggers out so they don’t get observed, there is a “known source” comment in the COMMENT section of the BAT alert notice.
In some cases it can still be useful to observe triggers on known sources, but occasionally Swift will trigger dozens of times on the same known source, and you’d spend all your time doing that (e.g. SGRs in outburst often produce dozens of triggers before their merit is lowered on the onboard computer on Swift).

See https://gcn.gsfc.nasa.gov/other/888312.swift.

Here's the sentinel log, with the VOEvent formatted a bit:

2019/02/09 14:29:40:DEBUG - Sentinel is Listening (9668 processed, 3 interesting)
2019/02/09 14:29:42:DEBUG - received packet of 7703 bytes
2019/02/09 14:29:42:DEBUG - payload is:

***************
<?xml version = '1.0' encoding = 'UTF-8'?>
<voe:VOEvent
      ivorn="ivo://nasa.gsfc.gcn/SWIFT#BAT_GRB_Pos_888312-735"
      role="observation" version="2.0"
      xmlns:voe="http://www.ivoa.net/xml/VOEvent/v2.0"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://www.ivoa.net/xml/VOEvent/v2.0  http://www.ivoa.net/xml/VOEvent/VOEvent-v2.0.xsd" >
  <Who>
    <AuthorIVORN>ivo://nasa.gsfc.tan/gcn</AuthorIVORN>
    <Author>
      <shortName>VO-GCN</shortName>
      <contactName>Scott Barthelmy</contactName>
      <contactPhone>+1-301-286-3106</contactPhone>
      <contactEmail>[email protected]</contactEmail>
    </Author>
    <Date>2019-02-09T14:29:55</Date>
    <Description>This VOEvent message was created with GCN VOE version: 1.33 06dec18</Description>
  </Who>
  <What>
    <Param name="Packet_Type"  value="61" />
    <Param name="Pkt_Ser_Num"  value="1" />
    <Param name="TrigID"       value="888312" ucd="meta.id" />
    <Param name="Segment_Num"  value="0" ucd="meta.id.part" />
    <Param name="Burst_TJD"    value="18523" unit="days" ucd="time" />
    <Param name="Burst_SOD"    value="52121.61" unit="sec" ucd="time" />
    <Param name="Burst_Inten"  value="0" unit="cts" ucd="phot.count;em.gamma.soft" />
    <Param name="Burst_Peak"   value="905" unit="cts" ucd="phot.count;em.gamma.soft" />
    <Param name="Integ_Time"   value="64.000" unit="sec" ucd="time.interval" />
    <Param name="Phi"          value="-18.49" unit="deg" ucd="pos.az.azi" />
    <Param name="Theta"        value="29.62" unit="deg" ucd="pos.az.zd" />
    <Param name="Trig_Index"   value="20000" />
    <Param name="Soln_Status"  value="0x299d" />
    <Param name="Misc_flags"   value="0x2000" />
    <Param name="Cat_Num"      value="10568" />
    <Param name="Rate_Signif"  value="0.00" unit="sigma" ucd="stat.snr" />
    <Param name="Image_Signif" value="6.03" unit="sigma" ucd="stat.snr" />
    <Param name="Bkg_Inten"    value="0" unit="cts" ucd="phot.count" />
    <Param name="Bkg_Time"     value="00:00:00.00" ucd="time.start" />
    <Param name="Bkg_Dur"      value="0.00" unit="sec" ucd="time.duration" />
    <Param name="SC_Long"      value="260.96" unit="deg" ucd="pos.earth.lon" />
    <Param name="SC_Lat"        value="6.18" unit="deg" ucd="pos.earth.lat" />
    <Group name="Merit_Values" >
      <Param name="Merit_Val0" value="0" unit="dn" />
      <Param name="Merit_Val1" value="0" unit="dn" />
      <Param name="Merit_Val2" value="95" unit="dn" />
      <Param name="Merit_Val3" value="6" unit="dn" />
      <Param name="Merit_Val4" value="1" unit="dn" />
      <Param name="Merit_Val5" value="-5" unit="dn" />
      <Param name="Merit_Val6" value="-100" unit="dn" />
      <Param name="Merit_Val7" value="1" unit="dn" />
      <Param name="Merit_Val8" value="-75" unit="dn" />
      <Param name="Merit_Val9" value="1" unit="dn" />
    </Group>
    <Group name="Solution_Status" >
      <Param name="Point_Source"             value="true" />
      <Param name="GRB_Identified"           value="false" />
      <Param name="Target_of_Interest"       value="true" />
      <Param name="Target_Imag_Trig"         value="true" />
      <Param name="Target_Rate_Trig"         value="false" />
      <Param name="Def_NOT_a_GRB"            value="false" />
      <Param name="Hi_Bkg_Level"             value="false" />
      <Param name="Neg_Bkg_Slope"            value="false" />
      <Param name="Lo_Image_Signif"          value="true" />
      <Param name="VERY_Lo_Image_Signif"     value="true" />
      <Param name="Target_in_Flt_Catalog"    value="true" />
      <Param name="Target_in_Gnd_Catalog"    value="true" />
      <Param name="Target_in_Blk_Catalog"    value="false" />
      <Param name="StarTrack_Lost_Lock"      value="false" />
      <Param name="Near_Bright_Star"         value="true" />
      <Param name="Src_Removed_from_OnBoard" value="false" />
      <Param name="Converted_SubThresh"      value="false" />
      <Param name="Spatial_Prox_Match"       value="false" />
      <Param name="Temporal_Prox_Match"      value="false" />
      <Param name="Test_Submission"          value="false" />
    </Group>
    <Group name="Misc_Flags" >
      <Param name="Values_Out_of_Range"        value="false" />
      <Param name="Already_Observing_Position" value="false" />
      <Param name="Near_Bright_Star"           value="true" />
      <Param name="Err_Circle_in_Galaxy"       value="false" />
      <Param name="Galaxy_in_Err_Circle"       value="false" />
      <Param name="ImTrig_during_ST_LoL"       value="false" />
      <Param name="TOO_Generated"              value="false" />
      <Param name="Trig_time_is_SecHdrTime"    value="false" />
      <Param name="Delayed_Transmission"       value="false" />
      <Param name="Updated_Notice"             value="false" />
      <Param name="Flt_Generated"              value="true" />
      <Param name="Gnd_Generated"              value="false" />
      <Param name="SERS_Generated"             value="false" />
      <Param name="Other_Generated"            value="false" />
      <Param name="CRC_Error"                  value="false" />
    </Group>
    <Param name="Coords_Type"   value="1" unit="dn" />
    <Param name="Coords_String" value="source_object" />
    <Group name="Obs_Support_Info" >
      <Description>The Sun and Moon values are valid at the time the VOEvent XML message was created.</Description>
      <Param name="Sun_RA"        value="322.94" unit="deg" ucd="pos.eq.ra" />
      <Param name="Sun_Dec"       value="-14.64" unit="deg" ucd="pos.eq.dec" />
      <Param name="Sun_Distance"  value="40.56" unit="deg" ucd="pos.angDistance" />
      <Param name="Sun_Hr_Angle"  value="2.45" unit="hr" />
      <Param name="Moon_RA"       value="13.07" unit="deg" ucd="pos.eq.ra" />
      <Param name="Moon_Dec"      value="0.05" unit="deg" ucd="pos.eq.dec" />
      <Param name="MOON_Distance" value="86.86" unit="deg" ucd="pos.angDistance" />
      <Param name="Moon_Illum"    value="18.96" unit="%" ucd="arith.ratio" />
      <Param name="Galactic_Long" value="37.24" unit="deg" ucd="pos.galactic.lon" />
      <Param name="Galactic_Lat"  value="-1.29" unit="deg" ucd="pos.galactic.lat" />
      <Param name="Ecliptic_Long" value="287.75" unit="deg" ucd="pos.ecliptic.lon" />
      <Param name="Ecliptic_Lat"  value="25.70" unit="deg" ucd="pos.ecliptic.lat" />
    </Group>
    <Description>Type=61: The Swift-BAT instrument position notice.</Description>
  </What>
  <WhereWhen>
    <ObsDataLocation>
      <ObservatoryLocation id="GEOLUN" />
      <ObservationLocation>
        <AstroCoordSystem id="UTC-FK5-GEO" />
        <AstroCoords coord_system_id="UTC-FK5-GEO">
          <Time unit="s">
            <TimeInstant>
              <ISOTime>2019-02-09T14:28:41.61</ISOTime>
            </TimeInstant>
          </Time>
          <Position2D unit="deg">
            <Name1>RA</Name1>
            <Name2>Dec</Name2>
            <Value2>
              <C1>285.9717</C1>
              <C2>3.2416</C2>
            </Value2>
            <Error2Radius>0.0666</Error2Radius>
          </Position2D>
        </AstroCoords>
      </ObservationLocation>
    </ObsDataLocation>
  <Description>The RA,Dec coordinates are of the type: source_object.</Description>
  </WhereWhen>
  <How>
    <Description>Swift Satellite, BAT Instrument</Description>
    <Reference uri="http://gcn.gsfc.nasa.gov/swift.html" type="url" />
  </How>
  <Why importance="0.90">
    <Inference probability="0.90">
      <Name>4U_1901+03</Name>
      <Concept>process.variation.burst;em.gamma</Concept>
    </Inference>
  </Why>
  <Description>
  </Description>
</voe:VOEvent>
***************
2019/02/09 14:29:42:INFO - received VOEvent
2019/02/09 14:29:42:DEBUG - sent receipt response
2019/02/09 14:29:42:INFO - Processing new event: ivo://nasa.gsfc.gcn/SWIFT#BAT_GRB_Pos_888312-735
2019/02/09 14:29:42:INFO - Archived to /home/goto/g-tecs-config/voevents
2019/02/09 14:29:42:INFO - Event is marked as "observation"
2019/02/09 14:29:42:INFO - Recognised event type: SWIFT_BAT_GRB_POS (GRB)
2019/02/09 14:29:42:INFO - Inserting event Swift_888312 into GOTO database
2019/02/09 14:29:42:INFO - Event Swift_888312 has no previous entry in the database
2019/02/09 14:29:42:DEBUG - Added 5 mpointings
2019/02/09 14:29:42:INFO - Database insersion complete
2019/02/09 14:29:43:WARNING - Target does not rise above minimum altitude at goto_north
2019/02/09 14:29:43:WARNING - Target does not rise above minimum altitude at goto_south
2019/02/09 14:29:43:INFO - Event Swift_888312 processed
2019/02/09 14:29:43:INFO - Interesting event Swift_888312 processed

There are things we could filter on, note "Lo_Image_Signif" and "VERY_Lo_Image_Signif" were both true.