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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"

36143 results found.

  1. GRB 990907 optical observations
  2. BATSE GRB trigger criteria
  3. Optical Observations of GRB990907
  4. IPN error box for GRB990915 (=BATSE 7766)
  5. IPN localization of BATSE #7766 (GRB990915)
  6. IPN localization of GRB990907
  7. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  8. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  9. GRB 990712 Late Optical Decay and Host Galaxy
  10. GRB 990712, Optical Observation
  11. GRB990806: BATSE Observations
  12. GRB 990806 Optical observations
  13. Optical Observations of GRB990806
  14. GRB 990806, Optical Observations
  15. GRB 990806, optical observations
  16. GRB 990806, Optical Observations
  17. GRB990806 UBVRIJHK observations
  18. BeppoSAX ALERT GRB990806: Summer GRB
  19. GRB 990712 Optical Observations
  20. GRB990705: No Evidence for Neutrino Signal
  21. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  22. VLT spectrum of GRB990712
  23. GRB 990712
  24. Late-time HST/STIS Observations of GRB 990510
  25. Refined BeppoSAX-WFC position of GRB990712
  26. GRB 990705, R-band observations
  27. Updated IPN localization of GRB990705
  28. IPN localization of GRB990704
  29. IPN localization of GRB990705
  30. Infrared and Optical Observations of GRB990705
  31. GRB 990705, radio observations
  32. GRB990704 radio and optical observations
  33. GRB 990704 X-ray Observations
  34. GRB 990704 Optical Observations
  35. GRB 990704, optical observations
  36. GRB990704
  37. GRB990705: Intriguing Positional Coincidences
  38. GRB990704
  39. GRB990704, optical observations
  40. Identification of a possible optical counterpart for GRB990704
  41. GRB990704
  42. Refined BeppoSAX-WFC position of GRB990704
  43. GRB990704: BeppoSAX detection
  44. Optical Observations of GRB990627
  45. GRB 990627, radio observations
  46. GRB990627: BeppoSAX-WFC final location
  47. BeppoSAX: GRB990625
  48. Late-time HST/STIS Observation of GRB 990123
  49. GRB 990506 - clarification to GCN 352
  50. GRB 990506 - Optical Observations
  51. Optical Observations of GRB 990506
  52. GRB 990506 Radio Transient
  53. GRB990527 Optical Observations
  54. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  55. IPN error box for GRB990527
  56. Late Afterglows of GRBs 990510, 990123
  57. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  58. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  59. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  60. GRB 990506 optical observation
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  62. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  63. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  64. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  65. radio observations of X-ray/GRB transient field
  66. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  67. Optical report on X-ray/GRB transient
  68. radio detection of X-ray/GRB transient
  69. BeppoSAX: A new fast X-ray transient
  70. GRB 990510: optical observations
  71. GRB990510: photometric and spectroscopic observations with the VLT
  72. GRB 990510: optical linear polarization
  73. GRB 990510: optical observations
  74. GRB990510, VI observations
  75. GRB 990506 R band observations
  76. GRB990510: X-ray afterglow
  77. GRB 990510: optical observation
  78. VLT spectrum of GRB990510
  79. GRB 990510: Broad Band Break
  80. GRB 990510: BATSE Observations
  81. GRB 990510 Optical Observations
  82. GRB 990510, BVI photometry
  83. GRB 990510 optical observations
  84. GRB 990510: BeppoSAX/GRBM observations
  85. GRB990510 optical observations
  86. GRB 990510 optical observations
  87. GRB 990510 optical observations
  88. Galactic extinction towards GRB 990510
  89. GRB 990510 optical observations
  90. IPN localization of GRB990510
  91. GRB 990506 Radio Observations
  92. GRB 990123, optical monitoring
  93. GRB 990506: BATSE Observations
  94. GRB 990506, optical observations
  95. GRB 990510: Final BeppoSAX-WFC Coordinates
  96. GRB 990506, Optical Observations
  97. GRB 990506 optical observations
  98. GRB 990506 optical observations
  99. GRB 990506, optical observations
  100. GRB990506 observation plan

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