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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"

36144 results found.

  1. GRB 990915 optical observations
  2. GRB 990907 optical observations
  3. BATSE GRB trigger criteria
  4. Optical Observations of GRB990907
  5. IPN error box for GRB990915 (=BATSE 7766)
  6. IPN localization of BATSE #7766 (GRB990915)
  7. IPN localization of GRB990907
  8. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  9. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  10. GRB 990712 Late Optical Decay and Host Galaxy
  11. GRB 990712, Optical Observation
  12. GRB990806: BATSE Observations
  13. GRB 990806 Optical observations
  14. Optical Observations of GRB990806
  15. GRB 990806, Optical Observations
  16. GRB 990806, optical observations
  17. GRB 990806, Optical Observations
  18. GRB990806 UBVRIJHK observations
  19. BeppoSAX ALERT GRB990806: Summer GRB
  20. GRB 990712 Optical Observations
  21. GRB990705: No Evidence for Neutrino Signal
  22. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  23. VLT spectrum of GRB990712
  24. GRB 990712
  25. Late-time HST/STIS Observations of GRB 990510
  26. Refined BeppoSAX-WFC position of GRB990712
  27. GRB 990705, R-band observations
  28. Updated IPN localization of GRB990705
  29. IPN localization of GRB990704
  30. IPN localization of GRB990705
  31. Infrared and Optical Observations of GRB990705
  32. GRB 990705, radio observations
  33. GRB990704 radio and optical observations
  34. GRB 990704 X-ray Observations
  35. GRB 990704 Optical Observations
  36. GRB 990704, optical observations
  37. GRB990704
  38. GRB990705: Intriguing Positional Coincidences
  39. GRB990704
  40. GRB990704, optical observations
  41. Identification of a possible optical counterpart for GRB990704
  42. GRB990704
  43. Refined BeppoSAX-WFC position of GRB990704
  44. GRB990704: BeppoSAX detection
  45. Optical Observations of GRB990627
  46. GRB 990627, radio observations
  47. GRB990627: BeppoSAX-WFC final location
  48. BeppoSAX: GRB990625
  49. Late-time HST/STIS Observation of GRB 990123
  50. GRB 990506 - clarification to GCN 352
  51. GRB 990506 - Optical Observations
  52. Optical Observations of GRB 990506
  53. GRB 990506 Radio Transient
  54. GRB990527 Optical Observations
  55. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  56. IPN error box for GRB990527
  57. Late Afterglows of GRBs 990510, 990123
  58. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  59. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  60. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  61. GRB 990506 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. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  66. radio observations of X-ray/GRB transient field
  67. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  68. Optical report on X-ray/GRB transient
  69. radio detection of X-ray/GRB transient
  70. BeppoSAX: A new fast X-ray transient
  71. GRB 990510: optical observations
  72. GRB990510: photometric and spectroscopic observations with the VLT
  73. GRB 990510: optical linear polarization
  74. GRB 990510: optical observations
  75. GRB990510, VI observations
  76. GRB 990506 R band observations
  77. GRB990510: X-ray afterglow
  78. GRB 990510: optical observation
  79. VLT spectrum of GRB990510
  80. GRB 990510: Broad Band Break
  81. GRB 990510: BATSE Observations
  82. GRB 990510 Optical Observations
  83. GRB 990510, BVI photometry
  84. GRB 990510 optical observations
  85. GRB 990510: BeppoSAX/GRBM observations
  86. GRB990510 optical observations
  87. GRB 990510 optical observations
  88. GRB 990510 optical observations
  89. Galactic extinction towards GRB 990510
  90. GRB 990510 optical observations
  91. IPN localization of GRB990510
  92. GRB 990506 Radio Observations
  93. GRB 990123, optical monitoring
  94. GRB 990506: BATSE Observations
  95. GRB 990506, optical observations
  96. GRB 990510: Final BeppoSAX-WFC Coordinates
  97. GRB 990506, Optical Observations
  98. GRB 990506 optical observations
  99. GRB 990506 optical observations
  100. GRB 990506, optical observations

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