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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"

35940 results found.

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

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