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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"

27516 results found.

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

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