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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"

19545 results found.

  1. Late-time HST/STIS Observation of GRB 990123
  2. Optical Observations of GRB 990506
  3. GRB 990506 Radio Transient
  4. GRB990527 Optical Observations
  5. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  6. IPN error box for GRB990527
  7. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  8. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  9. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  10. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  11. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  12. radio observations of X-ray/GRB transient field
  13. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  14. Optical report on X-ray/GRB transient
  15. radio detection of X-ray/GRB transient
  16. GRB 990510: optical linear polarization
  17. GRB 990510: optical observations
  18. GRB990510: X-ray afterglow
  19. GRB 990510 optical observations
  20. GRB990510: NFI X-ray source
  21. GRB 990506 Radio Observations
  22. GRB 990123, optical monitoring
  23. GRB 990506, optical observations
  24. GRB 990510: Final BeppoSAX-WFC Coordinates
  25. GRB 990506, Optical Observations
  26. GRB 990506 optical observations
  27. GRB 990506 optical observations
  28. GRB 990506, optical observations
  29. GRB990506 observation plan
  30. GRB 990506, optical observations from +1 to +3 hours
  31. GRB 990506, optical observations
  32. GRB990506 observation plan
  33. GRB 990316 Optical Observations
  34. GRB 990316 optical observations
  35. GRB990316: simultaneous optical observation
  36. GRB990308, Possible new SGR~0209+70
  37. GRB 990123, Field Photometry
  38. GRB 990217 Optical Observations
  39. BATSE Flight Anomaly
  40. GRB990217: BeppoSAX/GRBM data
  41. GRB990123 observations
  42. GRB990123, Optical Observation
  43. GRB 990123: Discovery of the Probable Host Galaxy
  44. GRB19990123 observations
  45. GRB 990123: BVRI standards in the field
  46. GRB981220, field photometry
  47. GRB990123, Optical observation
  48. GRB 990123: Publicly available reduced HST images
  49. GRB990123, Upcoming HST Service Observations
  50. GRB990123, 15-GHz limits
  51. GRB 990123: New Constraints on Possible Foreground Galaxies
  52. GRB990123 Optical Observations
  53. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  54. GRB 990123: Continued Radio Observations
  55. GRB990123, Preliminary Lens Search Results
  56. Search for Potential Images of GRB 990123
  57. GRB990123, Optical BVRI Observations
  58. GRB 990123: near-infrared observations.
  59. GRB990123, OSSE observations
  60. GRB990123: NIR Observation
  61. "GRB 990123: New BV Observations"
  62. GRB 990123: New Optical Observations, Decay Measure
  63. GRB 990123 Optical Follow-Up
  64. GRB 990123: Possible Gravitationally Lensed Burst?
  65. GRB990123, optical observation
  66. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  67. GRB 990123 r-band photometry
  68. GRB 990123 Optical Follow-up
  69. Optical Observations of GRB 981220
  70. GRB 981226: radio variable
  71. GRB 981226 Optical Observations
  72. GRB981226 BeppoSAX follow up
  73. GRB 981226
  74. GRB 981226 optical observations
  75. GRB 981220:Optical Observations
  76. GRB981226, BeppoSAX Christmas GRB
  77. GRB 981226 optical observations
  78. GRB 981220, radio observations
  79. GRB 981220
  80. GRB 980326/Host Galaxy
  81. BeppoSAX NFI Observation of GRB980425
  82. GRB980329 R,I flux calibration and R,I,K upper limits
  83. GRB980425 Optical Follow-up
  84. GRB970508 optical observations
  85. GRB980519, Optical Observations
  86. GRB 980703 (NFI observations)
  87. GRB980703 optical photometry
  88. GRB980703 optical observations
  89. GRB980703: Radio transient
  90. GRB980703 Transient Optical Follow-Up
  91. GRB980703: LOTIS observation at early times
  92. BeppoSAX NFI observations of GRB 980703
  93. GRB980703 optical followup
  94. SGR1627-41
  95. Radio observations of SGRs
  96. SGR1900+14 field optical observations
  97. GRB 980613 Near-IR observations
  98. GRB 980613: Optical transient and its host galaxy
  99. SGR1627-41, Refined IPN annulus location
  100. GRB 980613: Detection of the probable host galaxy

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