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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

34 results found.

  1. LIGO/Virgo S200115j: Zwicky Transient Facility search for optical counterparts to Swift X-ray sources
  2. LIGO/Virgo S200115j: Further Swift-XRT sources
  3. LIGO/Virgo S200115j: Upper limits from Konus-Wind observations
  4. LIGO/VIRGO S200115j: No obvious candidates from Pan-STARRS2 observations
  5. LIGO/Virgo S200115j: No counterpart detection within possible host galaxies observed by the GRAWITA-Savelli telescope
  6. LIGO/Virgo S200115j: GMOS-N upper limits for ZTF20aafqvyc/AT2020yq from the Gemini Observatory
  7. LIGO/Virgo S200115j : No significant candidates in TAROT - FRAM - GRANDMA observations
  8. LIGO/Virgo S200115j: Mondy upper limits for ZTF20aafqvyc/AT2020yq
  9. LIGO/Virgo S200115j: LCO upper limits for ZTF20aafqvyc/AT2020yq from the McDonald Observatory 1-m telescope
  10. LIGO/Virgo S200115j: NIR upper limits for ZTF20aafqvyc/AT2020yq from the Palomar 200-inch telescope
  11. LIGO/Virgo S200115j: Swift/UVOT observations of Swift/XRT S200115j_X136
  12. LIGO/Virgo S200115j: Updated Sky Localization and source properties
  13. LIGO/Virgo S200115j: Swift-XRT sources
  14. LIGO/Virgo S200115j: Upper limits from CALET observations.
  15. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  16. LIGO/Virgo S200115j: No neutrino candidates at Pierre Auger Observatory
  17. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  18. LIGO/Virgo S200115j: no counterpart candidates in the Swift/BAT observations
  19. LIGO/Virgo S200115j High Rank XRT sources are spurious
  20. LIGO/Virgo S200115j: No counterpart candidates in Fermi-LAT observations
  21. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  22. GRB 200115A: Swift detection of a burst
  23. LIGO/Virgo S200115j: upper limits from AGILE/GRID observations
  24. LIGO/Virgo S200115j: Candidates from the Zwicky Transient Facility
  25. LIGO/Virgo S200115j: INTEGRAL was inactive at the time of the event
  26. LIGO/Virgo S200115j: upper limits from AGILE/MCAL observations
  27. LIGO/Virgo S200115j: Revised list of possible host galaxies with the new skymap
  28. LIGO/Virgo S200115j : no neutrino counterpart candidate in ANTARES search
  29. LIGO/Virgo S200115j: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo S200115j: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  32. LIGO/Virgo S200115j: Upper limits from IceCube neutrino searches
  33. LIGO/Virgo trigger S200115j: Possible host galaxies
  34. LIGO/Virgo S200115j: Global MASTER-Net observations report

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