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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"

20951 results found.

  1. GRB 000210: BATSE Observations
  2. Optical observations of the Chandra X-ray source for GRB000210
  3. GRB000210, Radio Observations
  4. Optical candidate for GRB000210
  5. Chandra Observations of GRB000210 X-ray Afterglow
  6. GRB000201, Radio Observations
  7. Optical observations of GRB000131
  8. GRB000201 Optical Observations
  9. GRB 000201: TAROT optical observations
  10. GRB 000131 Optical Observations
  11. GRB000126 Optical Observations
  12. GRB 991208, radio observations
  13. GRB 000126, optical observations
  14. GRB000126, optical observations
  15. GRB 000115 Optical observations
  16. BATSE Observations of GRB000115
  17. GRB991216, UBVRIJHK field photometry
  18. GRB991216 late optical observation
  19. GRB 991216 VLBA Observations
  20. IPN error boxes for GRB991229
  21. GRB 991216: J band spectrophotometry
  22. GRB 991216 RXTE ASM Observations
  23. Lowell/Perkins observation of GRB 991216
  24. GRB 991217 (SAX J2303.2+0015) Optical observations
  25. GRB991217/SAX J2303.2+0015, optical observations
  26. GRB 991216, optical observations
  27. GRB 991216 Optical Observations
  28. GRB991216 Optical and IR observations
  29. K observations of GRB991216
  30. SAX J2303.2+0015 Optical observations
  31. IR observations of GRB991216
  32. GRB991216 radio observations
  33. GRB 991217 (SAX J2303.2+0015) Optical observations
  34. GRB991216 radio observations
  35. GRB991216, optical observations
  36. GRB991216 Optical and infrared observations of Beethoven Burst
  37. GRB 991216 Radio Observations
  38. GRB 991208 Keck Spectroscopy
  39. GRB 991216--Summary of RXTE Observations
  40. GRB 991216 Optical Observations
  41. GRB 991216, optical observations
  42. GRB 991216, Optical Transient
  43. GRB 991216, Optical Afterglow
  44. GRB991216 ('Beethoven Burst') B, R, and K Observations
  45. GRB991216, infrared observations
  46. GRB991216 Optical Observations
  47. GRB 991208 optical observations
  48. GRB 991208 Keck Spectroscopy
  49. GRB 991216: Extremely bright BATSE burst
  50. R-band Observations of GRB991208 at TNG
  51. GRB991208, optical observations
  52. GRB 991208 Keck Spectroscopy
  53. GRB991208 15-GHz observations
  54. GRB991208, optical observations
  55. GRB 991208 - OVRO detection
  56. GRB 991208 optical observations
  57. GRB 991208 optical observations
  58. GRB 991208: Radio Observations
  59. Optical Observations of GRB991105
  60. GRB991106: BeppoSAX/BATSE results
  61. GRB 991106, optical observations
  62. GRB991106, near-infrared observations
  63. GRB 991106, radio observations
  64. GRB 991105: BATSE Observations
  65. GRB 991106 Optical Observations
  66. GRB 991105, optical observations
  67. GRB 991106, LOTIS Optical Observations
  68. GRB 991106, optical observations
  69. GRB 991014, Optical Observations
  70. GRB 991014 - BeppoSAX NFI observations
  71. GRB 991014, Optical Observations
  72. GRB 991014, radio observations
  73. GRB991014 BATSE Observations
  74. GRB 991014, Optical Observations
  75. GRB 991014, optical observations
  76. GRB 990915 optical observations
  77. GRB 990907 optical observations
  78. Optical Observations of GRB990907
  79. GRB990907 and 990908
  80. GRB 990712 Late Optical Decay and Host Galaxy
  81. GRB 990712, Optical Observation
  82. GRB990806: BATSE Observations
  83. GRB 990806 Optical observations
  84. Optical Observations of GRB990806
  85. GRB 990806, Optical Observations
  86. GRB 990806, optical observations
  87. GRB 990806, Optical Observations
  88. GRB990806 UBVRIJHK observations
  89. GRB 990712 Optical Observations
  90. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  91. GRB 990712
  92. Late-time HST/STIS Observations of GRB 990510
  93. GRB 990705, R-band observations
  94. Infrared and Optical Observations of GRB990705
  95. GRB 990705, radio observations
  96. GRB990704 radio and optical observations
  97. GRB 990704 X-ray Observations
  98. GRB 990704 Optical Observations
  99. GRB 990704, optical observations
  100. GRB990704

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