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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"

27322 results found.

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

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