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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"

4953 results found.

  1. RXTE Observations of SGR 1900+14
  2. IPN Upper Limits to a GRB Associated With SN2002ap
  3. GRB020124 BVRI field photometry
  4. GRB020127 Optical Observations
  5. GRB 020124 Optical Observations
  6. GRB011212: Optical observations at Gunma
  7. GRB011212: Optical observations
  8. GRB 011211, Optical Observations
  9. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  10. BeppoSAX Alert: GRB011211(=XRF011211)
  11. GRB011130 (XRF011130) Chandra Observations
  12. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  13. GRB010921, optical observation
  14. GRB010921, optical observation at early time
  15. GRB010923 as seen by BeppoSAX GRBM
  16. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  17. GRB010214 Optical Observation
  18. BeppoSAX ALERT: GRB001109
  19. HETE positions added to GCN
  20. IPN triangulation of GRB 001004
  21. GRB000620, Radio Observations
  22. GRB 000615, near-infrared observations
  23. GRB000508B, optical photometry
  24. Possible GRB-related phenomenon
  25. GRB 000408, optical observations
  26. GRB000326, Radio observations
  27. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  28. GRB000301C: RXTE/ASM and IPN localizations
  29. GRB991216, optical observations
  30. GRB 991216, optical observations
  31. GRB 991216, Optical Transient
  32. GRB 991216, Optical Afterglow
  33. GRB991216 ('Beethoven Burst') B, R, and K Observations
  34. GRB991216, infrared observations
  35. Lowell/Perkins observation of GRB 991216
  36. GRB 990806, Optical Observations
  37. Updated Astrometry for the IR Counterpart of GRB990705
  38. GRB 990705, R-band observations
  39. IPN localization of GRB990705
  40. Infrared and Optical Observations of GRB990705
  41. GRB 990705, radio observations
  42. Refined BeppoSAX-WFC position of GRB990704: Errata Corrige
  43. GRB990704, optical observations
  44. GRB990323 PRECISE IPN POSITION
  45. GRB 990316, Optical observations
  46. On the Lensing Interpretation of GRB 990123
  47. GRB990123, early optical counterpart detection
  48. GRB 981220 Optical observations
  49. GRB981220 B, R and I band observations
  50. GRB 981220:Optical Observations
  51. GRB980703 optical photometry
  52. GRB980703 optical followup
  53. SGR1900+14 field optical observations

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