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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"

27121 results found.

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

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