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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

23217 results found.

  1. IPN annulus for GRB000214
  2. Optical observations of GRB000210
  3. GRB000210 X-ray afterglow
  4. GRB000214: X-ray afterglow candidate
  5. GRB000214 refined BeppoSAX-WFC position
  6. GRB 000210: BATSE Observations
  7. Optical observations of the Chandra X-ray source for GRB000210
  8. GRB000210, Radio Observations
  9. Optical candidate for GRB000210
  10. Chandra Observations of GRB000210 X-ray Afterglow
  11. GRB000210: possible afterglow detection with BeppoSAX NFI
  12. GRB000201, Radio Observations
  13. GRB000210: BeppoSAX GRBM and WFC Detection
  14. Optical observations of GRB000131
  15. GRB000201 Optical Observations
  16. GRB 000131 Optical Observations
  17. BATSE+IPN location of GRB000131
  18. IPN localization of GRB000131
  19. GRB 000126, optical observations
  20. IPN localization of GRB000126
  21. BATSE Observations of GRB000115
  22. GRB991216, UBVRIJHK field photometry
  23. GCN resumes full operations
  24. GRB 991216 VLBA Observations
  25. IPN error boxes for GRB991229
  26. GRB 991216: Detection of the Host and/or Absorber Galaxy
  27. IPN localization of GRB991226
  28. IPN error boxes for GRB991221
  29. GRB 991216 RXTE ASM Observations
  30. GRB 991216: Updated BATSE parameters
  31. GRB 991217 (SAX J2303.2+0015) Optical observations
  32. GRB991217/SAX J2303.2+0015, optical observations
  33. Chandra observation of the X-ray afterglow of GRB991216
  34. K observations of GRB991216
  35. SAX J2303.2+0015 Optical observations
  36. IR observations of GRB991216
  37. GRB 991217 (SAX J2303.2+0015) Optical observations
  38. GRB 991216 Radio Observations
  39. GRB 991208 Infrared Detection
  40. GRB991216
  41. GRB 991216--Summary of RXTE Observations
  42. GRB 991216 Optical Observations
  43. GRB 991216, optical observations
  44. GRB 991208 SAO-RAS Spectroscopy
  45. SAX J2303.2+0015: an x-ray/GRB?
  46. GRB 991216, Optical Transient
  47. GRB991216 ('Beethoven Burst') B, R, and K Observations
  48. GRB991216, infrared observations
  49. GRB 991208 optical observations
  50. GRB 991216 Optical Observation
  51. GRB 991208 Keck Spectroscopy
  52. GRB 991216: Extremely bright BATSE burst
  53. GRB991208, optical observations
  54. GRB 991208, Optical Observation
  55. GRB991208, optical observations
  56. IPN localization of GRB991208
  57. Optical Observations of GRB991105
  58. GRB991106: BeppoSAX/BATSE results
  59. GRB 991106, optical observations
  60. BeppoSAX NFI Observation of GRB991106
  61. GRB 991106, radio observations
  62. GRB991106: the first BeppoSAX short GRB detection?
  63. GRB 991105: BATSE Observations
  64. GRB 991106 Optical Observations
  65. GRB991106, optical observation at SAO-RAS
  66. GRB 991106, LOTIS Optical Observations
  67. GRB991105: SAX-GRBM/-WFC detection
  68. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  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. Super-LOTIS optical observation of GRB991014
  77. IPN localization of GRB991014 - CORRECTION
  78. IPN localization of GRB991014
  79. GRB 990907 optical observations
  80. Optical Observations of GRB990907
  81. GRB990907: BeppoSAX follow up and X-ray afterglow
  82. GRB990907 and 990908
  83. IPN localization of GRB990907
  84. GRB 990712, Optical Observation
  85. GRB990806 BeppoSAX follow up
  86. GRB990806: BATSE Observations
  87. GRB 990806 Optical observations
  88. GRB 990806, Optical Observations
  89. GRB 990806, optical observations
  90. GRB 990806, Optical Observations
  91. GRB990806 UBVRIJHK observations
  92. GRB990806: possible X-ray afterglow, BeppoSAX
  93. GRB 990712 Optical Observations
  94. GRB 990712
  95. Late-time HST/STIS Observations of GRB 990510
  96. Refined BeppoSAX-WFC position of GRB990712
  97. BeppoSAX NFI Observation of GRB990705
  98. BeppoSAX NFI Observation of GRB990705
  99. GRB 990705, R-band observations
  100. Updated IPN localization of GRB990705

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