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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"

24806 results found.

  1. GRB 981226: radio variable
  2. GRB981220
  3. GRB981220, Correction to GCN 179
  4. GRB 981220 Optical observations
  5. GRB 981226 Optical Observations
  6. GRB 981220 and GRB 981226, optical observations
  7. GRB981226 Optical Observations
  8. GRB981226 BeppoSAX follow up
  9. GRB 981226
  10. GRB 981226 optical observations
  11. GRB981220 B, R and I band observations
  12. Optical Observations of GRB981226
  13. GRB 981220:Optical Observations
  14. GRB 981226 optical observations
  15. GRB 981220
  16. GRB 981220, radio observations
  17. GRB981220 I-band Observations
  18. GRB 981220
  19. GRB 980326/Host Galaxy
  20. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  21. BeppoSAX NFI Observation of GRB980425
  22. GRB980329 R,I flux calibration and R,I,K upper limits
  23. GRB980425 Optical Follow-up
  24. GRB 980923 BATSE Observations
  25. SGR1900+14, BeppoSAX-GRBM observations
  26. GRB970508 optical observations
  27. GRB971214, association with a Galactic star?
  28. GRB980519, Optical Observations
  29. GRB980703 - BeppoSAX/GRBM detection
  30. GRB980703 optical photometry
  31. GRB 980703: BATSE Observations
  32. GRB980703 optical observations
  33. GRB980703: Radio transient
  34. GRB 980703: Spectrum of the proposed optical counterpart
  35. GRB980703 Transient Optical Follow-Up
  36. GRB980703: LOTIS observation at early times
  37. GRB980613 Optical Observations
  38. GRB980703 (I band observations)
  39. BeppoSAX NFI observations of GRB 980703
  40. GRB980519 observation report
  41. GRB980703 optical followup
  42. Radio observations of SGRs
  43. SGR1900+14 field optical observations
  44. GRB980613, optical observations
  45. GRB 980613: Optical transient and its host galaxy
  46. SGR1627-41, RXTE/ASM observations
  47. GRB 980613: Detection of the probable host galaxy
  48. Reduced error box of SGR 1627-41
  49. GRB 980613: BATSE Observations
  50. GRB 980613 Optical Observations
  51. GRB 980613 optical observations
  52. Discovery of a new SGR source, SGR1627-41
  53. GRB980613 Optical Observations
  54. GRB980613 observations from Palomar
  55. GRB 980613 optical/IR obs.
  56. GRB980613 Near Infra-Red Observations
  57. GRB971214 Secondary Standards
  58. GRB980519 Secondary Standards
  59. BATSE on-board GRB trigger change
  60. GRB 980519 Optical Observations
  61. GRB 980519
  62. GRB980519 optical observations
  63. GRB 980519 Optical Observations
  64. GRB980519 BATSE Observations
  65. GRB980519 Optical Observations
  66. GRB980519 Optical Observations
  67. GRB 980519 Optical Observations
  68. GRB980515, BeppoSAX IAUC to be submitted
  69. BSAX Observations of GRB980425 field
  70. IPN web site of GRBs
  71. GRB980425 BATSE observations
  72. SAX J0840.7+2248 Optical Observations
  73. GRB980425: optical obs.
  74. GRB980425: Radio Observations
  75. report on BSAX observations of GRB980425
  76. GRB 980329 ROSAT observation
  77. GRB980326 X-ray Observations
  78. GRB980326, optical observations
  79. GRB980326, optical observations
  80. GRB980329, Fading IR counterpart to radio source
  81. GRB980329 Keck K-band observations
  82. GRB980329 sub-millimeter observations
  83. GRB980329 optical observations
  84. GRB980329 near-IR observations
  85. GRB980329 near-IR observations
  86. GRB980326 optical observations
  87. GRB980329 optical observations
  88. GRB980329 VLA observations
  89. GRB980329 optical observations
  90. GRB980329 optical observations
  91. GRB980326 optical observations
  92. GRB980326 optical observations
  93. Optical Observations of GRB 970508
  94. Near-IR follow-up on GRB 971227
  95. Optical Observations of the GRB 971227 field
  96. Optical Observations on GRB 971227
  97. GRB971227: Plaskett R-band observations
  98. GRB 971227: Optical clarifications
  99. GRB971227: Further CAHA R-band images
  100. GRB971227: LOTIS observations

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