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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"

27319 results found.

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

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