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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"

24705 results found.

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

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