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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').

22429 results found.

  1. GRB 991106, LOTIS Optical Observations
  2. GRB991105: SAX-GRBM/-WFC detection
  3. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  4. GRB 991014, Optical Observations
  5. GRB 991014 - BeppoSAX NFI observations
  6. GRB 991014, radio observations
  7. GRB 991014, Optical Observations
  8. GRB 991014, optical observations
  9. GRB 990915 optical observations
  10. Optical Observations of GRB990907
  11. GRB990907: BeppoSAX follow up and X-ray afterglow
  12. GRB990907 and 990908
  13. GRB 990712 Late Optical Decay and Host Galaxy
  14. GRB990806 BeppoSAX follow up
  15. GRB990806: BATSE Observations
  16. GRB 990806 Optical observations
  17. GRB 990806, Optical Observations
  18. GRB 990806, optical observations
  19. GRB 990806, Optical Observations
  20. GRB990806 UBVRIJHK observations
  21. GRB 990712 Optical Observations
  22. GRB 990712
  23. Late-time HST/STIS Observations of GRB 990510
  24. BeppoSAX NFI Observation of GRB990705
  25. BeppoSAX NFI Observation of GRB990705
  26. GRB 990705, R-band observations
  27. Infrared and Optical Observations of GRB990705
  28. GRB990704: SAX-NFI results summary
  29. GRB990704 radio and optical observations
  30. GRB990704
  31. GRB990704, optical observations
  32. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  33. Optical Observations of GRB990627
  34. BeppoSAX: GRB990625
  35. Late-time HST/STIS Observation of GRB 990123
  36. Optical Observations of GRB 990506
  37. GRB990527 Optical Observations
  38. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  39. Late Afterglows of GRBs 990510, 990123
  40. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  41. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  42. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  43. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  44. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  45. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  46. radio observations of X-ray/GRB transient field
  47. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  48. Optical report on X-ray/GRB transient
  49. radio detection of X-ray/GRB transient
  50. BeppoSAX: A new fast X-ray transient
  51. GRB 990510: optical observations
  52. GRB 990510: optical linear polarization
  53. GRB 990510: optical observations
  54. GRB990510: X-ray afterglow
  55. GRB 990510: Broad Band Break
  56. GRB 990510: BATSE Observations
  57. GRB 990510: BeppoSAX/GRBM observations
  58. GRB990510 optical observations
  59. GRB 990510 optical observations
  60. GRB 990506 Radio Observations
  61. GRB 990123, optical monitoring
  62. GRB 990506: BATSE Observations
  63. GRB 990506, optical observations
  64. GRB 990506, Optical Observations
  65. GRB 990506 optical observations
  66. GRB 990506, optical observations
  67. GRB 990506, armchair astronomy
  68. GRB 990506, optical observations from +1 to +3 hours
  69. GRB 990506, optical observations
  70. GRB990506 observation plan
  71. IPN localization for GRB990506
  72. GRB990323 PRECISE IPN POSITION
  73. GRB 990316 Optical Observations
  74. GRB 990316 optical observations
  75. GRB990316: simultaneous optical observation
  76. GRB990316 - Optical null results
  77. GRB990308 not a new SGR
  78. GRB 990308a and GRB 990308b
  79. GRB990308, Possible new SGR~0209+70
  80. GRB 990123, Field Photometry
  81. GRB 990217 Optical Observations
  82. BATSE Flight Anomaly
  83. GRB990217: BeppoSAX/GRBM data
  84. GRB990123 observations
  85. GRB990217 Optical observation
  86. GRB990123, Optical Observation
  87. GRB 990123: Discovery of the Probable Host Galaxy
  88. GRB 990123: Reduced HST Images
  89. GRB19990123 observations
  90. GRB 990123: BVRI standards in the field
  91. GRB981220, field photometry
  92. GRB990123, Optical observation
  93. GRB990123, 15-GHz limits
  94. GRB 990123: New Constraints on Possible Foreground Galaxies
  95. GRB990123 Optical Observations
  96. GRB990123, Probability of gravitational lensing
  97. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  98. GRB990123, Preliminary Lens Search Results
  99. On the Lensing Interpretation of GRB 990123
  100. Search for Potential Images of GRB 990123

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