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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"

35937 results found.

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

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