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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"

35949 results found.

  1. GRB 991014, optical observations
  2. Super-LOTIS optical observation of GRB991014
  3. IPN/NFI error box for GRB991014
  4. IPN localization of GRB991014 - CORRECTION
  5. IPN localization of GRB991014
  6. BeppoSAX ALERT: GRB991014
  7. GRB 990915 optical observations
  8. GRB 990907 optical observations
  9. BATSE GRB trigger criteria
  10. Optical Observations of GRB990907
  11. IPN error box for GRB990915 (=BATSE 7766)
  12. IPN localization of BATSE #7766 (GRB990915)
  13. IPN localization of GRB990907
  14. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  15. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  16. GRB 990712 Late Optical Decay and Host Galaxy
  17. GRB 990712, Optical Observation
  18. GRB990806: BATSE Observations
  19. GRB 990806 Optical observations
  20. Optical Observations of GRB990806
  21. GRB 990806, Optical Observations
  22. GRB 990806, optical observations
  23. GRB 990806, Optical Observations
  24. GRB990806 UBVRIJHK observations
  25. BeppoSAX ALERT GRB990806: Summer GRB
  26. GRB 990712 Optical Observations
  27. GRB990705: No Evidence for Neutrino Signal
  28. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  29. VLT spectrum of GRB990712
  30. GRB 990712
  31. Late-time HST/STIS Observations of GRB 990510
  32. Refined BeppoSAX-WFC position of GRB990712
  33. GRB 990705, R-band observations
  34. Updated IPN localization of GRB990705
  35. IPN localization of GRB990704
  36. IPN localization of GRB990705
  37. Infrared and Optical Observations of GRB990705
  38. GRB 990705, radio observations
  39. GRB990704 radio and optical observations
  40. GRB 990704 X-ray Observations
  41. GRB 990704 Optical Observations
  42. GRB 990704, optical observations
  43. GRB990704
  44. GRB990705: Intriguing Positional Coincidences
  45. GRB990704
  46. GRB990704, optical observations
  47. Identification of a possible optical counterpart for GRB990704
  48. GRB990704
  49. Refined BeppoSAX-WFC position of GRB990704
  50. GRB990704: BeppoSAX detection
  51. Optical Observations of GRB990627
  52. GRB 990627, radio observations
  53. GRB990627: BeppoSAX-WFC final location
  54. BeppoSAX: GRB990625
  55. Late-time HST/STIS Observation of GRB 990123
  56. GRB 990506 - clarification to GCN 352
  57. GRB 990506 - Optical Observations
  58. Optical Observations of GRB 990506
  59. GRB 990506 Radio Transient
  60. GRB990527 Optical Observations
  61. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  62. IPN error box for GRB990527
  63. Late Afterglows of GRBs 990510, 990123
  64. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  65. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  66. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  67. GRB 990506 optical observation
  68. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  69. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  70. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  71. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  72. radio observations of X-ray/GRB transient field
  73. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  74. Optical report on X-ray/GRB transient
  75. radio detection of X-ray/GRB transient
  76. BeppoSAX: A new fast X-ray transient
  77. GRB 990510: optical observations
  78. GRB990510: photometric and spectroscopic observations with the VLT
  79. GRB 990510: optical linear polarization
  80. GRB 990510: optical observations
  81. GRB990510, VI observations
  82. GRB 990506 R band observations
  83. GRB990510: X-ray afterglow
  84. GRB 990510: optical observation
  85. VLT spectrum of GRB990510
  86. GRB 990510: Broad Band Break
  87. GRB 990510: BATSE Observations
  88. GRB 990510 Optical Observations
  89. GRB 990510, BVI photometry
  90. GRB 990510 optical observations
  91. GRB 990510: BeppoSAX/GRBM observations
  92. GRB990510 optical observations
  93. GRB 990510 optical observations
  94. GRB 990510 optical observations
  95. Galactic extinction towards GRB 990510
  96. GRB 990510 optical observations
  97. IPN localization of GRB990510
  98. GRB 990506 Radio Observations
  99. GRB 990123, optical monitoring
  100. GRB 990506: BATSE Observations

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