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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"

28681 results found.

  1. GRB980613 Optical Observations
  2. GRB 980703
  3. GRB980703 (I band observations)
  4. GRB 980703 H-band Observations
  5. GRB980703: radio source/optical transient
  6. BeppoSAX NFI observations of GRB 980703
  7. GRB980519 observation report
  8. Radio observations of SGRs
  9. GRB 980613 Near-IR observations
  10. GRB980613, optical observations
  11. GRB 980613: Optical transient and its host galaxy
  12. SGR1627-41, RXTE/ASM observations
  13. SGR1627-41, Refined IPN annulus location
  14. GRB 980613: Detection of the probable host galaxy
  15. Reduced error box of SGR 1627-41
  16. SGR1627-41, BeppoSAX-GRBM detections
  17. GRB 980613 Optical Observations
  18. GRB 980613 optical observations
  19. GRB980613 Optical Observations
  20. GRB980613 observations from Palomar
  21. GRB 980613 new optical/IR observations
  22. GRB971214 Secondary Standards
  23. GRB980519 Secondary Standards
  24. SGR1900+14
  25. GRB 980519 Optical Observations
  26. GRB980519 optical observations
  27. GRB980519 I-band observations
  28. GRB 980519
  29. GRB980519 optical observations
  30. GRB 980519 Optical Observations
  31. GRB980519 BATSE Observations
  32. GRB970519, optical follow-up at Schmidt Calern
  33. GRB980519 optical observations
  34. GRB980519 Optical Observations
  35. GRB980519 Optical Observations
  36. GRB980519 IPN POSITION
  37. GRB980519 Optical Observations
  38. GRB 980519 Optical Observations
  39. GRB980519 optical observations
  40. GRB980515, BeppoSAX IAUC to be submitted
  41. GRB980519, BeppoSAX-WFC updated position
  42. GRB 980425 Radio Light Curve
  43. GRB 980425 Brightness Temperature
  44. BSAX Observations of GRB980425 field
  45. IPN web site of GRBs
  46. GRB980425 BATSE observations
  47. SAX J0840.7+2248 Optical Observations
  48. GRB 980425 optical observations
  49. GRB980425: optical obs.
  50. GRB980425: Radio Observations
  51. GRB 980425 optical observations
  52. GRB980326, optical observations
  53. GRB980326, optical observations
  54. GRB980329, Fading IR counterpart to radio source
  55. GRByymmdd, Announcement of automation
  56. GRB980326 IPN annulus
  57. GRB980329
  58. GRB980329 Keck K-band observations
  59. GRB980329 sub-millimeter observations
  60. GRB980329 IPN annulus
  61. GRB980329 optical observations
  62. GRB980329 near-IR observations
  63. GRB980329 optical observations
  64. GRB980326 optical observations
  65. GRB980326 optical observations
  66. GRB970508 SAO RAS optical observations
  67. GRB 971214: Redshift from Keck Observations
  68. Near-IR follow-up on GRB 971227
  69. GRB971214: Keck R & I-band Observations
  70. GRB 971227: Optical Observations
  71. Optical Observations of the GRB 971227 field
  72. GRB971227: Plaskett R-band observations
  73. GRB 971227: Optical clarifications
  74. GRB971227: LOTIS observations
  75. GRB971214: Optical Observations and Calibrations
  76. Optical Observations of GRB 971214 at Keck
  77. GRB 971024: Refined analysis by USNOFS Observations
  78. GRB 971024: USNO Observations
  79. GRB 970925: BATSE Localization
  80. IRAS 18119-1342 and the possible new SGR
  81. GRB 970228: Keck/LRIS Optical Observations

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