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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"

35429 results found.

  1. GRB 990806, optical observations
  2. GRB 990806, Optical Observations
  3. GRB990806 UBVRIJHK observations
  4. BeppoSAX ALERT GRB990806: Summer GRB
  5. GRB 990712 Optical Observations
  6. GRB990705: No Evidence for Neutrino Signal
  7. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  8. VLT spectrum of GRB990712
  9. GRB 990712
  10. Late-time HST/STIS Observations of GRB 990510
  11. Refined BeppoSAX-WFC position of GRB990712
  12. GRB 990705, R-band observations
  13. Updated IPN localization of GRB990705
  14. IPN localization of GRB990704
  15. IPN localization of GRB990705
  16. Infrared and Optical Observations of GRB990705
  17. GRB 990705, radio observations
  18. GRB990704 radio and optical observations
  19. GRB 990704 X-ray Observations
  20. GRB 990704 Optical Observations
  21. GRB 990704, optical observations
  22. GRB990704
  23. GRB990705: Intriguing Positional Coincidences
  24. GRB990704
  25. GRB990704, optical observations
  26. Identification of a possible optical counterpart for GRB990704
  27. GRB990704
  28. Refined BeppoSAX-WFC position of GRB990704
  29. GRB990704: BeppoSAX detection
  30. Optical Observations of GRB990627
  31. GRB 990627, radio observations
  32. GRB990627: BeppoSAX-WFC final location
  33. BeppoSAX: GRB990625
  34. Late-time HST/STIS Observation of GRB 990123
  35. GRB 990506 - clarification to GCN 352
  36. GRB 990506 - Optical Observations
  37. Optical Observations of GRB 990506
  38. GRB 990506 Radio Transient
  39. GRB990527 Optical Observations
  40. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  41. IPN error box for GRB990527
  42. Late Afterglows of GRBs 990510, 990123
  43. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  44. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  45. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  46. GRB 990506 optical observation
  47. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  48. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  49. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  50. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  51. radio observations of X-ray/GRB transient field
  52. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  53. Optical report on X-ray/GRB transient
  54. radio detection of X-ray/GRB transient
  55. BeppoSAX: A new fast X-ray transient
  56. GRB 990510: optical observations
  57. GRB990510: photometric and spectroscopic observations with the VLT
  58. GRB 990510: optical linear polarization
  59. GRB 990510: optical observations
  60. GRB990510, VI observations
  61. GRB 990506 R band observations
  62. GRB990510: X-ray afterglow
  63. GRB 990510: optical observation
  64. VLT spectrum of GRB990510
  65. GRB 990510: Broad Band Break
  66. GRB 990510: BATSE Observations
  67. GRB 990510 Optical Observations
  68. GRB 990510, BVI photometry
  69. GRB 990510 optical observations
  70. GRB 990510: BeppoSAX/GRBM observations
  71. GRB990510 optical observations
  72. GRB 990510 optical observations
  73. GRB 990510 optical observations
  74. Galactic extinction towards GRB 990510
  75. GRB 990510 optical observations
  76. IPN localization of GRB990510
  77. GRB 990506 Radio Observations
  78. GRB 990123, optical monitoring
  79. GRB 990506: BATSE Observations
  80. GRB 990506, optical observations
  81. GRB 990510: Final BeppoSAX-WFC Coordinates
  82. GRB 990506, Optical Observations
  83. GRB 990506 optical observations
  84. GRB 990506 optical observations
  85. GRB 990506, optical observations
  86. GRB990506 observation plan
  87. Refined IPN error box for GRB990506
  88. GRB 990506: Limits on the possible optical transient
  89. GRB 990506, armchair astronomy
  90. GRB 990506, optical observations from +1 to +3 hours
  91. GRB 990506, optical observations
  92. GRB990506 observation plan
  93. New IPN/RXTE error box for GRB990506
  94. IPN localization for GRB990506
  95. GRB 970228: Redshift and properties of the host galaxy
  96. IPN localization of GRB990427
  97. GRB981220 VLBA observations
  98. GRB990321 REFINED IPN ANNULUS
  99. GRB990323 PRECISE IPN POSITION
  100. GRB990321 IPN TRIANGULATION

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