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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"

31728 results found.

  1. GRB 981226: radio variable
  2. GRB981220
  3. GRB981220, Correction to GCN 179
  4. GRB981220, Optical Observations
  5. GRB 981220 Optical observations
  6. GRB 981226 Optical Observations
  7. GRB 980613: Spectroscopy of the host galaxy
  8. GRB981226, sub-millimeter observations
  9. GRB981220, sub-millimeter observations
  10. GRB 981220 and GRB 981226, optical observations
  11. GRB981226 Optical Observations
  12. GRB 981226 radio observations
  13. GRB 981226
  14. radio observations of GRB 981226
  15. GRB981220 B, R and I band observations
  16. Optical Observations of GRB981226
  17. GRB 981220:Optical Observations
  18. GRB 981220 optical R and I observations
  19. GRB981226, BeppoSAX Christmas GRB
  20. GRB 981226 - Infrared Observations
  21. GRB 981220
  22. GRB 981220, radio observations
  23. GRB 981220, radio observations
  24. GRB 981220: BeppoSAX/GRBM results
  25. GRB981220 I-band Observations
  26. GRB 981220
  27. GRB 981220 Optical Observations
  28. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  29. BeppoSAX NFI Observation of GRB980425
  30. GRB980425 Optical Follow-up
  31. GRB980425: X-ray revised positions
  32. GRB980703 Very Long Baseline Interferometry
  33. GRB970508 optical observations
  34. Optical Observations of the Host Galaxy of GRB 980519
  35. GRB980519, Optical Observations
  36. GRB980703, Host galaxy multicolor photometry
  37. GRB 980703 (NFI observations)
  38. GRB980703 optical photometry
  39. GRB 980703: BATSE Observations
  40. GRB980703 optical observations
  41. GRB980703: Radio transient
  42. GRB980703 H-band Observations
  43. GRB 980703: Spectrum of the proposed optical counterpart
  44. RXTE Observation of GRB 980706
  45. GRB980703: Spectrum of the proposed optical counterpart
  46. GRB980703 Transient Optical Follow-Up
  47. GRB980703: LOTIS observation at early times
  48. GRB980613 Optical Observations
  49. GRB 980703
  50. GRB980703 (I band observations)
  51. GRB 980703 H-band Observations
  52. GRB980703: radio source/optical transient
  53. BeppoSAX NFI observations of GRB 980703
  54. GRB980519 observation report
  55. Radio observations of SGRs
  56. GRB 980613 Near-IR observations
  57. GRB980613, optical observations
  58. GRB 980613: Optical transient and its host galaxy
  59. SGR1627-41, RXTE/ASM observations
  60. SGR1627-41, Refined IPN annulus location
  61. GRB 980613: Detection of the probable host galaxy
  62. Reduced error box of SGR 1627-41
  63. SGR1627-41, BeppoSAX-GRBM detections
  64. GRB 980613 Optical Observations
  65. GRB 980613 optical observations
  66. GRB980613 Optical Observations
  67. GRB980613 observations from Palomar
  68. GRB 980613 new optical/IR observations
  69. GRB971214 Secondary Standards
  70. GRB980519 Secondary Standards
  71. SGR1900+14
  72. GRB 980519 Optical Observations
  73. GRB980519 optical observations
  74. GRB980519 I-band observations
  75. GRB 980519
  76. GRB980519 optical observations
  77. GRB 980519 Optical Observations
  78. GRB980519 BATSE Observations
  79. GRB970519, optical follow-up at Schmidt Calern
  80. GRB980519 optical observations
  81. GRB980519 Optical Observations
  82. GRB980519 Optical Observations
  83. GRB980519 IPN POSITION
  84. GRB980519 Optical Observations
  85. GRB 980519 Optical Observations
  86. GRB980519 optical observations
  87. GRB980515, BeppoSAX IAUC to be submitted
  88. GRB980519, BeppoSAX-WFC updated position
  89. GRB 980425 Radio Light Curve
  90. GRB 980425 Brightness Temperature
  91. BSAX Observations of GRB980425 field
  92. IPN web site of GRBs
  93. GRB980425 BATSE observations
  94. SAX J0840.7+2248 Optical Observations
  95. GRB 980425 optical observations
  96. GRB980425: optical obs.
  97. GRB980425: Radio Observations
  98. GRB 980425 optical observations
  99. GRB980326, optical observations
  100. GRB980326, optical observations

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