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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').

19109 results found.

  1. GRB 991216 Optical Observation
  2. GRB 991216: Extremely bright BATSE burst
  3. R-band Observations of GRB991208 at TNG
  4. GRB991208, optical observations
  5. GRB 991208, Optical Observation
  6. GRB991208, optical observations
  7. GRB 991208 Optical Decay
  8. Optical Observations of GRB991105
  9. GRB991106: BeppoSAX/BATSE results
  10. GRB 991106, optical observations
  11. BeppoSAX NFI Observation of GRB991106
  12. GRB 991106, radio observations
  13. GRB991106: the first BeppoSAX short GRB detection?
  14. GRB 991106 Optical Observations
  15. GRB991106, optical observation at SAO-RAS
  16. GRB 991106, LOTIS Optical Observations
  17. GRB991105: SAX-GRBM/-WFC detection
  18. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  19. GRB ALERT: GRB991105
  20. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  21. GRB 991014, Optical Observations
  22. GRB 991014 - BeppoSAX NFI observations
  23. GRB 991014, radio observations
  24. GRB 991014, Optical Observations
  25. GRB 991014, optical observations
  26. Super-LOTIS optical observation of GRB991014
  27. Optical Observations of GRB990907
  28. GRB990907 and 990908
  29. GRB990806 BeppoSAX follow up
  30. GRB 990806 Optical observations
  31. Optical Observations of GRB990806
  32. GRB 990806, Optical Observations
  33. GRB 990806, optical observations
  34. GRB 990806, Optical Observations
  35. GRB 990712 Optical Observations
  36. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  37. GRB 990712
  38. Late-time HST/STIS Observations of GRB 990510
  39. Refined BeppoSAX-WFC position of GRB990712
  40. BeppoSAX NFI Observation of GRB990705
  41. BeppoSAX NFI Observation of GRB990705
  42. Updated Astrometry for the IR Counterpart of GRB990705
  43. GRB 990705, R-band observations
  44. Infrared and Optical Observations of GRB990705
  45. GRB 990705, radio observations
  46. GRB990704: SAX-NFI results summary
  47. GRB990704 radio and optical observations
  48. GRB990704
  49. GRB990704, optical observations
  50. GRB 990627, radio observations
  51. Late-time HST/STIS Observation of GRB 990123
  52. Optical Observations of GRB 990506
  53. GRB990527 Optical Observations
  54. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  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. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  59. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  60. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  61. radio observations of X-ray/GRB transient field
  62. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  63. Optical report on X-ray/GRB transient
  64. GRB 990510: optical linear polarization
  65. GRB 990510: optical observations
  66. GRB990510, VI observations
  67. GRB 990510: BATSE Observations
  68. GRB 990510: BeppoSAX/GRBM observations
  69. GRB 990510 optical observations
  70. GRB 990506 Radio Observations
  71. GRB 990123, optical monitoring
  72. GRB 990506, optical observations
  73. GRB 990506, Optical Observations
  74. GRB 990506 optical observations
  75. GRB 990506, optical observations
  76. GRB 990506, optical observations from +1 to +3 hours
  77. GRB 990506, optical observations
  78. GRB990506 observation plan
  79. GRB981220 VLBA observations
  80. GRB 990316 Optical Observations
  81. GRB 990316 optical observations
  82. GRB990316: simultaneous optical observation
  83. GRB990316 - Optical null results
  84. GRB 990123, Field Photometry
  85. GRB 990217 Optical Observations
  86. GRB 990217, radio observations
  87. BATSE Flight Anomaly
  88. GRB990123 observations
  89. GRB990123, Optical Observation
  90. GRB 990123: Discovery of the Probable Host Galaxy
  91. GRB 990123: Reduced HST Images
  92. GRB19990123 observations
  93. GRB 990123: BVRI standards in the field
  94. GRB981220, field photometry
  95. GRB990123, Optical observation
  96. GRB990123, 15-GHz limits
  97. GRB 990123: New Constraints on Possible Foreground Galaxies
  98. GRB990123 Optical Observations
  99. GRB990123, Probability of gravitational lensing
  100. GRB 990123: Detection of the IR Transient, and the Light Curve Fits

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