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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"

16 results found.

  1. LIGO/Virgo S190701ah: No counterpart candidates in Fermi-LAT observations
  2. LIGO/Virgo S190701ah: GRAWITA VST-ESO PARANAL observations
  3. LIGO/Virgo S190701ah: Updated sky localization
  4. LIGO/Virgo S190701ah: KMTNet Observation
  5. LIGO/Virgo S190701ah: No transient candidates from CALET observations
  6. LIGO/Virgo S190701ah: Upper limits from Insight-HXMT/HE observations
  7. LIGO/Virgo S190701ah: No counterpart candidates in the Swift/BAT Observations
  8. LIGO/Virgo S190701ah: Upper limits from AGILE-GRID observations
  9. LIGO/Virgo S190701ah: Upper limits from Fermi-GBM Observations
  10. LIGO/Virgo S190701ah Global MASTER-Net observations report
  11. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S190701ah: No counterpart candidates in AGILE-MCAL observations
  13. LIGO/Virgo S190701ah: No neutrino counterpart candidates in ANTARES search
  14. LIGO/Virgo S190701ah: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  15. LIGO/Virgo S190701ah: Identification of a GW compact binary merger candidate
  16. LIGO/Virgo S190701ah: Upper limits from IceCube neutrino searches

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Download all Circulars as a .tar.gz archive:
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