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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"

35 results found.

  1. LIGO/Virgo G297595/GW170814: updated localization from parameter estimation
  2. LIGO/Virgo G297595: NIR Observations following GW170814
  3. LIGO/Virgo G297595: PIRATE observations
  4. LIGO/Virgo G297595: LSGT observation of nearby galaxies
  5. LIGO/Virgo G297595: DLT40 follow-up observation
  6. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  7. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  8. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  9. LIGO/Virgo G297595: Gemini and VLT observations by GLGW Hunters
  10. LIGO/Virgo G297595: H.E.S.S. very-high energy gamma-ray follow-up
  11. LIGO/Virgo G298048: MASTER observations of the NGC 4993
  12. LIGO/Virgo G297595: Pierre Auger Observatory neutrino follow-up
  13. LIGO/Virgo G297595: Liverpool Telescope observations of MASTER transients
  14. LIGO/Virgo G297595: Swift-XRT sources
  15. LIGO/Virgo G297595: Konus-Wind observations
  16. LIGO/Virgo G297595: MASTER MASTER Bright PSN detection in error-box
  17. LIGO/Virgo G297595: INAF VST-ESO PARANAL observations
  18. LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
  19. LIGO/Virgo G297595: REM optical/NIR observations
  20. LIGO/Virgo G297595 : MAXI/GSC observations
  21. LIGO/Virgo G297595: Updated localization from LIGO and Virgo data
  22. LIGO/Virgo G297595: Correction to luminosity distance stated in GCN 21474
  23. LIGO/Virgo G297595: Pan-STARRS coverage and transients over the first 5hrs
  24. LIGO/Virgo G297595: Insight-HXMT observations
  25. LIGO/Virgo G297595: Nearby Galaxies in the Localization Volume
  26. LIGO/Virgo G297595: Fermi GBM Observations
  27. LIGO/Virgo G297595: Swift/BAT data search
  28. LIGO/Virgo G297595: AGILE GRID observations
  29. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart
  30. LIGO/Virgo G297595 ANTARES search
  31. LIGO/Virgo G297595: INTEGRAL search for a prompt gamma-ray counterpart
  32. LIGO/Virgo G297595: AGILE MCAL observations
  33. LIGO/Virgo G297595: SPI-ACS/INTEGRAL data investigations
  34. LIGO/Virgo G297595: IceCube neutrino observations
  35. LIGO/Virgo G297595: Identification of a GW Binary Merger Candidate

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