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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"

26499 results found.

  1. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  2. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  3. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  4. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  5. radio observations of X-ray/GRB transient field
  6. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  7. Optical report on X-ray/GRB transient
  8. BeppoSAX: A new fast X-ray transient
  9. GRB990510: photometric and spectroscopic observations with the VLT
  10. GRB 990510: optical linear polarization
  11. GRB 990510: optical observations
  12. GRB990510, VI observations
  13. GRB 990510: Broad Band Break
  14. GRB 990510: BATSE Observations
  15. GRB990510: optical observation
  16. GRB 990510: BeppoSAX/GRBM observations
  17. GRB990510 optical observations
  18. GRB 990510 optical observations
  19. GRB 990510 optical observations
  20. GRB 990506 Radio Observations
  21. GRB 990123, optical monitoring
  22. GRB 990506: BATSE Observations
  23. GRB 990506, optical observations
  24. GRB 990506, Optical Observations
  25. GRB 990506 optical observations
  26. GRB 990506, optical observations
  27. GRB 990506, optical observations from +1 to +3 hours
  28. GRB 990506, optical observations
  29. GRB990506 observation plan
  30. GRB 990316 Optical Observations
  31. GRB 990316, Radio observations
  32. GRB 990316, Optical observations
  33. GRB990316, Optical observations
  34. GRB 990316 optical observations
  35. GRB990316: simultaneous optical observation
  36. GRB990316 - Optical null results
  37. ASM/IPN error box for GRB 990308 (BATSE #7457)
  38. GRB 990308a and GRB 990308b
  39. GRB990308 (Trig. 7457), optical observations
  40. GRB990308, Possible new SGR~0209+70
  41. GRB 990123, Field Photometry
  42. GRB 990217 Optical Observations
  43. BATSE Flight Anomaly
  44. GRB990217: BeppoSAX/GRBM data
  45. GRB990123 observations
  46. GRB990217 Optical observation
  47. GRB990123, Optical Observation
  48. GRB 990123: Discovery of the Probable Host Galaxy
  49. GRB19990123 observations
  50. GRB 990123: BVRI standards in the field
  51. GRB981220, field photometry
  52. GRB990123, Optical observation
  53. GRB990123, 15-GHz limits
  54. GRB 990123: New Constraints on Possible Foreground Galaxies
  55. GRB990123 Optical Observations
  56. GRB990123, Probability of gravitational lensing
  57. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  58. GRB 990123: Continued Radio Observations
  59. GRB990123, Preliminary Lens Search Results
  60. On the Lensing Interpretation of GRB 990123
  61. Search for Potential Images of GRB 990123
  62. GRB990123, Optical BVRI Observations
  63. GRB 990123: near-infrared observations.
  64. GRB990123, OSSE observations
  65. GRB990123: NIR Observation
  66. GRB990123, ASCA X-ray observation of afterglow
  67. "GRB 990123: New BV Observations"
  68. GRB 990123 Optical Follow-Up
  69. GRB 990123: BATSE Observations
  70. GRB990123 IPN annulus
  71. GRB 990123 Spectroscopic Redshifts
  72. GRB 990123: New Optical Observations, Decay Measure
  73. GRB 990123 Optical Follow-Up
  74. GRB 990123: Possible Gravitationally Lensed Burst?
  75. GRB990123, optical observation
  76. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  77. GRB 990123, new radio source
  78. GRB990123, Optical observation
  79. GRB 990123 r-band photometry
  80. GRB 990123 Optical Follow-up
  81. GRB990123 Optical Observation
  82. GRB990123, refined SAX-WFC position
  83. Possible identification of SN1999E with GRB980910
  84. Optical Observations of GRB 981220
  85. GRB 981226: radio variable
  86. GRB981220
  87. GRB 981220 Optical observations
  88. GRB 981226 Optical Observations
  89. GRB981226 Optical Observations
  90. GRB981226 BeppoSAX follow up
  91. GRB 981226
  92. GRB 981226 optical observations
  93. Optical Observations of GRB981226
  94. GRB 981220:Optical Observations
  95. GRB 981226 optical observations
  96. GRB 981220
  97. GRB 981220, radio observations
  98. GRB 981220
  99. GRB 981220, optical observations
  100. GRB 980326/Host Galaxy

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