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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 100901A: errata of GRB name in GCN 11270
  2. GRB 100901A: optical observations in Mondy and R-light curve
  3. GRB 100901A: optical observation in Maidanak, break confirmation
  4. GRB100901A: IAO optical upper limits at 4 days after the burst
  5. EVLA detection of radio afterglow of GRB100901A
  6. GRB 100901A: Confirmation of WSRT Radio Detection
  7. GRB 100901A: CrAO optical observations
  8. GRB 100901A: TLS Detection at 5.5 days
  9. GRB 100901A: TLS observations, SDSS calibration, decay slope
  10. GRB 100901A: ISON-NM optical observations
  11. GRB 100901A: Possible WSRT Radio Detection
  12. Optical observations of GRB 100901A
  13. GRB10901A: Murikabushi telescope observation at 3 days after the burst
  14. GRB 100901A: Submm observations from SMA
  15. GRB 100901A: UKIRT zYJHK Observation
  16. GRB10901A: Optical observations at IAO
  17. GRB 100901A: optical observation at Mt.Terskol
  18. GRB 100901A: multicolor photometry at Mt.Terskol
  19. GRB 100901A: Lightbuckets Optical Observations
  20. GRB 100901A: HCT optical observations
  21. GRB 100901A: optical observation at Mt.Terskol
  22. GRB 100901A: Kanata Telescope observation of the optical afterglow
  23. GRB100901A: MITSuME Okayama Optical Observation at 1 day after the burst
  24. GRB 100901A: TLS Observations: Break?
  25. GRB 100901A: ISON-NM optical observations
  26. GRB 100901A: 1.5m OSN BVRI-band observations.
  27. GRB 100901A: ROTSE-III Detection
  28. GRB 100901A: MASTER optical flare at 420s discovery
  29. GRB 100901A: Vega telescope optical afterglow observation
  30. Swift/UVOT Observations of GRB100901A
  31. GRB 100901A : HCT optical observations
  32. GRB 100901A: SARA-N observations
  33. GRB 100901A: THO optical observations
  34. GRB100901A: MITSuME Okayama Optical Observation
  35. GRB 100901A: Swift-XRT Team refined analysis
  36. GRB 100901A - NOT optical observation
  37. GRB 100901A: Swift-BAT refined analysis
  38. GRB 100901A: optical observation at Mt.Terskol
  39. GRB 100901A: Enhanced Swift-XRT position
  40. GRB 100901A: optical observation at Mt.Terskol
  41. GRB 100901A: MASTER power low decay
  42. GRB 100901A: Gemini-N Redshift
  43. GRB 100901A: MASTER: the OT brightenning
  44. GRB 100901A: confirmation of the afterglow
  45. GRB 100901A: MASTER Optical Early Limits
  46. GRB 100901A: Faulkes Telescope North afterglow candidate
  47. GRB 100901A: Swift detection of a burst with an optical afterglow

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