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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"

32537 results found.

  1. GRB 990123: Optical Decay Slope
  2. GRB 990123 r-band photometry
  3. GRB 990123 Optical Follow-up
  4. GRB990123, early optical counterpart detection
  5. GRB990123 Optical Observation
  6. GRB 990123: Bright New Source, Possible Optical Transient
  7. GRB 990123, Radio observations
  8. SN 1999E & GRB 980919
  9. Optical Observations of GRB 981220
  10. GRB 981226: radio variable
  11. GRB981220
  12. GRB981220, Correction to GCN 179
  13. GRB981220, Optical Observations
  14. GRB 981220 Optical observations
  15. GRB 981226 Optical Observations
  16. GRB 980613: Spectroscopy of the host galaxy
  17. GRB981226, sub-millimeter observations
  18. GRB981220, sub-millimeter observations
  19. GRB 981220 and GRB 981226, optical observations
  20. GRB981226 Optical Observations
  21. GRB 981226 radio observations
  22. GRB 981226
  23. radio observations of GRB 981226
  24. GRB981220 B, R and I band observations
  25. Optical Observations of GRB981226
  26. GRB 981220:Optical Observations
  27. GRB 981220 optical R and I observations
  28. GRB981226, BeppoSAX Christmas GRB
  29. GRB 981226 - Infrared Observations
  30. GRB 981220
  31. GRB 981220, radio observations
  32. GRB 981220, radio observations
  33. GRB 981220: BeppoSAX/GRBM results
  34. GRB981220 I-band Observations
  35. GRB 981220
  36. GRB 981220 Optical Observations
  37. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  38. BeppoSAX NFI Observation of GRB980425
  39. GRB980425 Optical Follow-up
  40. GRB980425: X-ray revised positions
  41. GRB980703 Very Long Baseline Interferometry
  42. GRB970508 optical observations
  43. Optical Observations of the Host Galaxy of GRB 980519
  44. GRB980519, Optical Observations
  45. GRB980703, Host galaxy multicolor photometry
  46. GRB 980703 (NFI observations)
  47. GRB980703 optical photometry
  48. GRB 980703: BATSE Observations
  49. GRB980703 optical observations
  50. GRB980703: Radio transient
  51. GRB980703 H-band Observations
  52. GRB 980703: Spectrum of the proposed optical counterpart
  53. RXTE Observation of GRB 980706
  54. GRB980703: Spectrum of the proposed optical counterpart
  55. GRB980703 Transient Optical Follow-Up
  56. GRB980703: LOTIS observation at early times
  57. GRB980613 Optical Observations
  58. GRB 980703
  59. GRB980703 (I band observations)
  60. GRB 980703 H-band Observations
  61. GRB980703: radio source/optical transient
  62. BeppoSAX NFI observations of GRB 980703
  63. GRB980519 observation report
  64. Radio observations of SGRs
  65. GRB 980613 Near-IR observations
  66. GRB980613, optical observations
  67. GRB 980613: Optical transient and its host galaxy
  68. SGR1627-41, RXTE/ASM observations
  69. SGR1627-41, Refined IPN annulus location
  70. GRB 980613: Detection of the probable host galaxy
  71. Reduced error box of SGR 1627-41
  72. SGR1627-41, BeppoSAX-GRBM detections
  73. GRB 980613 Optical Observations
  74. GRB 980613 optical observations
  75. GRB980613 Optical Observations
  76. GRB980613 observations from Palomar
  77. GRB 980613 new optical/IR observations
  78. GRB971214 Secondary Standards
  79. GRB980519 Secondary Standards
  80. SGR1900+14
  81. GRB 980519 Optical Observations
  82. GRB980519 optical observations
  83. GRB980519 I-band observations
  84. GRB 980519
  85. GRB980519 optical observations
  86. GRB 980519 Optical Observations
  87. GRB980519 BATSE Observations
  88. GRB970519, optical follow-up at Schmidt Calern
  89. GRB980519 optical observations
  90. GRB980519 Optical Observations
  91. GRB980519 Optical Observations
  92. GRB980519 IPN POSITION
  93. GRB980519 Optical Observations
  94. GRB 980519 Optical Observations
  95. GRB980519 optical observations
  96. GRB980515, BeppoSAX IAUC to be submitted
  97. GRB980519, BeppoSAX-WFC updated position
  98. GRB 980425 Radio Light Curve
  99. GRB 980425 Brightness Temperature
  100. BSAX Observations of GRB980425 field

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