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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"

47 results found.

  1. GRB 141121A: GMG observation
  2. Radio upper limit on the GRB 141121A with the GMRT
  3. GRB 141121A: Keck observations
  4. GRB 141121A: further VLA observations
  5. GRB 141121A: Mondy optical observations
  6. GRB 141121A: Continued RATIR Optical Observations
  7. GRB 141121A: VLA radio detection
  8. GRB 141121A: Continued RATIR Optical Observations
  9. GRB 141121A: Mondy optical observations
  10. GRB 141121A: TSHAO optical observations
  11. GRB 141121A: Continued RATIR Optical Observations
  12. GRB 141121A: RATIR Optical Observations - Errata for GCN 17105
  13. GRB 141121A: MITSuME Ishigakijima Optical Observation after 7 days
  14. GRB 141121A: Khureltogot optical observations
  15. IPN Triangulation of GRB 141121A (initial episode)
  16. GRB 141121A: Mondy optical observations
  17. GRB 141121A: SPI-ACS/INTEGRAL observations
  18. GRB 141121A: RATIR Optical and NIR Observations
  19. Konus-Wind observation of GRB 141121A
  20. GRB 141121A: three epochs of SAO RAS optical observations
  21. GRB 141121A: Continued RATIR Optical Observations
  22. GRB 141121A: WSRT radio detection
  23. GRB 141121A: TSHAO optical observations
  24. GRB 141121A: Continued Mondy optical observations
  25. GRB 141121A: Continued RATIR Optical Observations
  26. GRB 141121A: RATIR Optical Observations - Steeper Fading
  27. GRB 141121A: AMI 15 GHz detection
  28. GRB 141121A: MITSuME Ishigakijima Optical Observation after 3 days
  29. GRB 141121A: RATIR Optical Observations - Fading Again
  30. GRB 141121A: Mondy optical observations
  31. GRB 141121A: LCO-FTN rebrightening confirmation
  32. GRB 141121A: MITSuME Ishigakijima Optical Observation
  33. GRB 141121A: Continued RATIR Optical Observations - Rebrightening
  34. GRB 141121A: AAO optical observations
  35. GRB 141121A: MITSuME Akeno Optical observation
  36. GRB 141121A: Continued RATIR Optical Observations
  37. GRB 141121A: Swift-XRT refined Analysis
  38. GRB 141121A: Swift/UVOT Detections
  39. GRB 141121A: RATIR Optical Observations
  40. GRB 141121A: Swift-BAT refined analysis
  41. GRB 141121A: LCO-FTN observations
  42. GRB 141121A: Keck redshift
  43. GRB 141121A: Enhanced Swift-XRT position
  44. GRB 141121A: GROND Afterglow candidate
  45. GRB 141121A: MAXI/GSC detection
  46. GRB141121A: BOOTES-2/TELMA upper limit
  47. GRB 141121A: Swift detection of a burst

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