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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"

32495 results found.

  1. IPN error box for GRB990915 (=BATSE 7766)
  2. IPN localization of BATSE #7766 (GRB990915)
  3. GRB990907: BeppoSAX follow up and X-ray afterglow
  4. GRB990907 and 990908
  5. IPN localization of GRB990907
  6. GRB 990712 Late Optical Decay and Host Galaxy
  7. GRB 990712, Optical Observation
  8. GRB990806 BeppoSAX follow up
  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. 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. BeppoSAX NFI Observation of GRB990705
  21. BeppoSAX NFI Observation of GRB990705
  22. Updated Astrometry for the IR Counterpart of GRB990705
  23. GRB 990705, R-band observations
  24. Updated IPN localization of GRB990705
  25. IPN localization of GRB990704
  26. IPN localization of GRB990705
  27. Infrared and Optical Observations of GRB990705
  28. GRB 990705, radio observations
  29. GRB990704: SAX-NFI results summary
  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. GRB990704
  36. Refined BeppoSAX-WFC position of GRB990704: Errata Corrige
  37. GRB990704, optical observations
  38. GRB990704: possible X-ray afterglow
  39. Identification of a possible optical counterpart for GRB990704
  40. GRB990704
  41. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  42. Optical Observations of GRB990627
  43. GRB 990627, radio observations
  44. GRB990627: BeppoSAX-WFC final location
  45. GRB 990506 - clarification to GCN 352
  46. GRB 990506 - Optical Observations
  47. Optical Observations of GRB 990506
  48. GRB 990506 Radio Transient
  49. GRB990527 Optical Observations
  50. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  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, VI observations
  67. GRB 990506 R band observations
  68. GRB990510: X-ray afterglow
  69. VLT spectrum of GRB990510
  70. GRB 990510: Broad Band Break
  71. GRB 990510: BATSE Observations
  72. GRB990510: optical observation
  73. GRB 990510 Optical Observations
  74. GRB 990510, BVI photometry
  75. GRB 990510 optical observations
  76. GRB990510 optical observations
  77. GRB990510
  78. GRB 990510 optical observations
  79. GRB 990510 optical observations
  80. Galactic extinction towards GRB 990510
  81. IPN localization of GRB990510
  82. GRB 990506 Radio Observations
  83. GRB 990506: BATSE Observations
  84. GRB 990506, optical observations
  85. GRB 990506, Optical Observations
  86. GRB 990506 optical observations
  87. GRB 990506 optical observations
  88. GRB 990506, optical observations
  89. GRB990506 observation plan
  90. GRB 990506: Limits on the possible optical transient
  91. GRB 990506, armchair astronomy
  92. GRB 990506, optical observations from +1 to +3 hours
  93. GRB 990506, optical observations
  94. GRB990506 observation plan
  95. New IPN/RXTE error box for GRB990506
  96. IPN localization for GRB990506
  97. GRB 970228: Redshift and properties of the host galaxy
  98. GRB981220 VLBA observations
  99. GRB990321 REFINED IPN ANNULUS
  100. GRB990323 PRECISE IPN POSITION

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