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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.

Lucene Examples (click to copy):

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

3035 results found.

  1. GRB030418: Kiso near infrared observations
  2. GRB030329: Near Infrared Observations at Gunma
  3. GRB 030329: fading X-ray afterglow with RXTE
  4. XMM-Newton observation of GRB030227
  5. GRB 030115: Further IR observations with IRSF/SIRIUS
  6. GRB 030115: IR observations with IRSF/SIRIUS
  7. GRB 021201, optical observations
  8. GRB 021201 (short/hard), NOT observations
  9. Chandra observation of the IPN error box of GRB021201 (short/hard)
  10. Detection of activity from SGR 1900+14 with the RXTE/PCA
  11. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  12. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  13. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  14. SGR-like Bursts from the AXP 1E 2259+586
  15. GRB 020418, optical/near-IR observations
  16. GRB020531, optical observations
  17. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  18. GRB 020321: Candidate X-ray Counterparts
  19. GRB 020331: Candidate Optical Afterglow
  20. GRB 020331: NIR Observations
  21. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  22. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  23. GRB 011121: NIR observations, host galaxy?
  24. GRB 011121: Detection of Bright IR Counterpart
  25. SGR 1900+14 : RXTE observations
  26. GRB 001204: Ks observations
  27. GRB 001212 possible OA in 2MASS
  28. GRB 001109: deep JHK upper limits
  29. The Likely Optical/Infrared Afterglow of GRB 001011
  30. SGR 1806-20 burst activity
  31. GRB 000418: Detection of the Host Galaxy
  32. X-ray Afterglow of GRB 000529
  33. IR observations of GRB991216
  34. BeppoSAX NFI Observation of GRB991106
  35. GRB980703: Radio transient

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