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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"

28686 results found.

  1. GRB 980703: Spectrum of the proposed optical counterpart
  2. RXTE Observation of GRB 980706
  3. GRB980703: Spectrum of the proposed optical counterpart
  4. GRB980703 Transient Optical Follow-Up
  5. GRB980703: LOTIS observation at early times
  6. GRB980613 Optical Observations
  7. GRB 980703
  8. GRB980703 (I band observations)
  9. GRB 980703 H-band Observations
  10. GRB980703: radio source/optical transient
  11. BeppoSAX NFI observations of GRB 980703
  12. GRB980519 observation report
  13. Radio observations of SGRs
  14. GRB 980613 Near-IR observations
  15. GRB980613, optical observations
  16. GRB 980613: Optical transient and its host galaxy
  17. SGR1627-41, RXTE/ASM observations
  18. SGR1627-41, Refined IPN annulus location
  19. GRB 980613: Detection of the probable host galaxy
  20. Reduced error box of SGR 1627-41
  21. SGR1627-41, BeppoSAX-GRBM detections
  22. GRB 980613 Optical Observations
  23. GRB 980613 optical observations
  24. GRB980613 Optical Observations
  25. GRB980613 observations from Palomar
  26. GRB 980613 new optical/IR observations
  27. GRB971214 Secondary Standards
  28. GRB980519 Secondary Standards
  29. SGR1900+14
  30. GRB 980519 Optical Observations
  31. GRB980519 optical observations
  32. GRB980519 I-band observations
  33. GRB 980519
  34. GRB980519 optical observations
  35. GRB 980519 Optical Observations
  36. GRB980519 BATSE Observations
  37. GRB970519, optical follow-up at Schmidt Calern
  38. GRB980519 optical observations
  39. GRB980519 Optical Observations
  40. GRB980519 Optical Observations
  41. GRB980519 IPN POSITION
  42. GRB980519 Optical Observations
  43. GRB 980519 Optical Observations
  44. GRB980519 optical observations
  45. GRB980515, BeppoSAX IAUC to be submitted
  46. GRB980519, BeppoSAX-WFC updated position
  47. GRB 980425 Radio Light Curve
  48. GRB 980425 Brightness Temperature
  49. BSAX Observations of GRB980425 field
  50. IPN web site of GRBs
  51. GRB980425 BATSE observations
  52. SAX J0840.7+2248 Optical Observations
  53. GRB 980425 optical observations
  54. GRB980425: optical obs.
  55. GRB980425: Radio Observations
  56. GRB 980425 optical observations
  57. GRB980326, optical observations
  58. GRB980326, optical observations
  59. GRB980329, Fading IR counterpart to radio source
  60. GRByymmdd, Announcement of automation
  61. GRB980326 IPN annulus
  62. GRB980329
  63. GRB980329 Keck K-band observations
  64. GRB980329 sub-millimeter observations
  65. GRB980329 IPN annulus
  66. GRB980329 optical observations
  67. GRB980329 near-IR observations
  68. GRB980329 optical observations
  69. GRB980326 optical observations
  70. GRB980326 optical observations
  71. GRB970508 SAO RAS optical observations
  72. GRB 971214: Redshift from Keck Observations
  73. Near-IR follow-up on GRB 971227
  74. GRB971214: Keck R & I-band Observations
  75. GRB 971227: Optical Observations
  76. Optical Observations of the GRB 971227 field
  77. GRB971227: Plaskett R-band observations
  78. GRB 971227: Optical clarifications
  79. GRB971227: LOTIS observations
  80. GRB971214: Optical Observations and Calibrations
  81. Optical Observations of GRB 971214 at Keck
  82. GRB 971024: Refined analysis by USNOFS Observations
  83. GRB 971024: USNO Observations
  84. GRB 970925: BATSE Localization
  85. IRAS 18119-1342 and the possible new SGR
  86. GRB 970228: Keck/LRIS Optical Observations

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