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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"

14 results found.

  1. LIGO/Virgo S190924h: Correction to GCN 25905, updated sky localization for S190924h
  2. LIGO/Virgo S190828h: Updated Sky Localization
  3. LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
  4. LIGO/Virgo S190924h: Not observable by CALET
  5. LIGO/Virgo S190924h: no counterpart candidates in the Swift/BAT observations
  6. LIGO/Virgo S190924h: Upper limits from Fermi-GBM Observations
  7. LIGO/Virgo S190924h: no counterpart candidates in AGILE-GRID observations
  8. LIGO/Virgo S190924h: No counterpart candidates in AGILE-MCAL observations
  9. LIGO/Virgo S190924h: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  10. LIGO/Virgo S190924h : no neutrino counterpart candidate in ANTARES search
  11. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S190924h: Global MASTER-Net observations report
  13. LIGO/Virgo S190924h: Identification of a GW compact binary merger candidate
  14. LIGO/Virgo S190924h: Upper limits from IceCube neutrino searches

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Download all Circulars as a .tar.gz archive:
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