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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"

25720 results found.

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

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