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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"

36947 results found.

  1. IPN/NFI error box for GRB991014
  2. IPN localization of GRB991014 - CORRECTION
  3. IPN localization of GRB991014
  4. BeppoSAX ALERT: GRB991014
  5. GRB 990915 optical observations
  6. GRB 990907 optical observations
  7. BATSE GRB trigger criteria
  8. Optical Observations of GRB990907
  9. IPN error box for GRB990915 (=BATSE 7766)
  10. IPN localization of BATSE #7766 (GRB990915)
  11. IPN localization of GRB990907
  12. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  13. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  14. GRB 990712 Late Optical Decay and Host Galaxy
  15. GRB 990712, Optical Observation
  16. GRB990806: BATSE Observations
  17. GRB 990806 Optical observations
  18. Optical Observations of GRB990806
  19. GRB 990806, Optical Observations
  20. GRB 990806, optical observations
  21. GRB 990806, Optical Observations
  22. GRB990806 UBVRIJHK observations
  23. BeppoSAX ALERT GRB990806: Summer GRB
  24. GRB 990712 Optical Observations
  25. GRB990705: No Evidence for Neutrino Signal
  26. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  27. VLT spectrum of GRB990712
  28. GRB 990712
  29. Late-time HST/STIS Observations of GRB 990510
  30. Refined BeppoSAX-WFC position of GRB990712
  31. GRB 990705, R-band observations
  32. Updated IPN localization of GRB990705
  33. IPN localization of GRB990704
  34. IPN localization of GRB990705
  35. Infrared and Optical Observations of GRB990705
  36. GRB 990705, radio observations
  37. GRB990704 radio and optical observations
  38. GRB 990704 X-ray Observations
  39. GRB 990704 Optical Observations
  40. GRB 990704, optical observations
  41. GRB990704
  42. GRB990705: Intriguing Positional Coincidences
  43. GRB990704
  44. GRB990704, optical observations
  45. Identification of a possible optical counterpart for GRB990704
  46. GRB990704
  47. Refined BeppoSAX-WFC position of GRB990704
  48. GRB990704: BeppoSAX detection
  49. Optical Observations of GRB990627
  50. GRB 990627, radio observations
  51. GRB990627: BeppoSAX-WFC final location
  52. BeppoSAX: GRB990625
  53. Late-time HST/STIS Observation of GRB 990123
  54. GRB 990506 - clarification to GCN 352
  55. GRB 990506 - Optical Observations
  56. Optical Observations of GRB 990506
  57. GRB 990506 Radio Transient
  58. GRB990527 Optical Observations
  59. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  60. IPN error box for GRB990527
  61. Late Afterglows of GRBs 990510, 990123
  62. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  63. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  64. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  65. GRB 990506 optical observation
  66. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  67. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  68. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  69. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  70. radio observations of X-ray/GRB transient field
  71. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  72. Optical report on X-ray/GRB transient
  73. radio detection of X-ray/GRB transient
  74. BeppoSAX: A new fast X-ray transient
  75. GRB 990510: optical observations
  76. GRB990510: photometric and spectroscopic observations with the VLT
  77. GRB 990510: optical linear polarization
  78. GRB 990510: optical observations
  79. GRB990510, VI observations
  80. GRB 990506 R band observations
  81. GRB990510: X-ray afterglow
  82. GRB 990510: optical observation
  83. VLT spectrum of GRB990510
  84. GRB 990510: Broad Band Break
  85. GRB 990510: BATSE Observations
  86. GRB 990510 Optical Observations
  87. GRB 990510, BVI photometry
  88. GRB 990510 optical observations
  89. GRB 990510: BeppoSAX/GRBM observations
  90. GRB990510 optical observations
  91. GRB 990510 optical observations
  92. GRB 990510 optical observations
  93. Galactic extinction towards GRB 990510
  94. GRB 990510 optical observations
  95. IPN localization of GRB990510
  96. GRB 990506 Radio Observations
  97. GRB 990123, optical monitoring
  98. GRB 990506: BATSE Observations
  99. GRB 990506, optical observations
  100. GRB 990510: Final BeppoSAX-WFC Coordinates

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