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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"

28717 results found.

  1. GRB 981226 radio observations
  2. GRB 981226
  3. radio observations of GRB 981226
  4. GRB981220 B, R and I band observations
  5. Optical Observations of GRB981226
  6. GRB 981220:Optical Observations
  7. GRB 981220 optical R and I observations
  8. GRB981226, BeppoSAX Christmas GRB
  9. GRB 981226 - Infrared Observations
  10. GRB 981220
  11. GRB 981220, radio observations
  12. GRB 981220, radio observations
  13. GRB 981220: BeppoSAX/GRBM results
  14. GRB981220 I-band Observations
  15. GRB 981220
  16. GRB 981220 Optical Observations
  17. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  18. BeppoSAX NFI Observation of GRB980425
  19. GRB980425 Optical Follow-up
  20. GRB980425: X-ray revised positions
  21. GRB980703 Very Long Baseline Interferometry
  22. GRB970508 optical observations
  23. Optical Observations of the Host Galaxy of GRB 980519
  24. GRB980519, Optical Observations
  25. GRB980703, Host galaxy multicolor photometry
  26. GRB 980703 (NFI observations)
  27. GRB980703 optical photometry
  28. GRB 980703: BATSE Observations
  29. GRB980703 optical observations
  30. GRB980703: Radio transient
  31. GRB980703 H-band Observations
  32. GRB 980703: Spectrum of the proposed optical counterpart
  33. RXTE Observation of GRB 980706
  34. GRB980703: Spectrum of the proposed optical counterpart
  35. GRB980703 Transient Optical Follow-Up
  36. GRB980703: LOTIS observation at early times
  37. GRB980613 Optical Observations
  38. GRB 980703
  39. GRB980703 (I band observations)
  40. GRB 980703 H-band Observations
  41. GRB980703: radio source/optical transient
  42. BeppoSAX NFI observations of GRB 980703
  43. GRB980519 observation report
  44. Radio observations of SGRs
  45. GRB 980613 Near-IR observations
  46. GRB980613, optical observations
  47. GRB 980613: Optical transient and its host galaxy
  48. SGR1627-41, RXTE/ASM observations
  49. SGR1627-41, Refined IPN annulus location
  50. GRB 980613: Detection of the probable host galaxy
  51. Reduced error box of SGR 1627-41
  52. SGR1627-41, BeppoSAX-GRBM detections
  53. GRB 980613 Optical Observations
  54. GRB 980613 optical observations
  55. GRB980613 Optical Observations
  56. GRB980613 observations from Palomar
  57. GRB 980613 new optical/IR observations
  58. GRB971214 Secondary Standards
  59. GRB980519 Secondary Standards
  60. SGR1900+14
  61. GRB 980519 Optical Observations
  62. GRB980519 optical observations
  63. GRB980519 I-band observations
  64. GRB 980519
  65. GRB980519 optical observations
  66. GRB 980519 Optical Observations
  67. GRB980519 BATSE Observations
  68. GRB970519, optical follow-up at Schmidt Calern
  69. GRB980519 optical observations
  70. GRB980519 Optical Observations
  71. GRB980519 Optical Observations
  72. GRB980519 IPN POSITION
  73. GRB980519 Optical Observations
  74. GRB 980519 Optical Observations
  75. GRB980519 optical observations
  76. GRB980515, BeppoSAX IAUC to be submitted
  77. GRB980519, BeppoSAX-WFC updated position
  78. GRB 980425 Radio Light Curve
  79. GRB 980425 Brightness Temperature
  80. BSAX Observations of GRB980425 field
  81. IPN web site of GRBs
  82. GRB980425 BATSE observations
  83. SAX J0840.7+2248 Optical Observations
  84. GRB 980425 optical observations
  85. GRB980425: optical obs.
  86. GRB980425: Radio Observations
  87. GRB 980425 optical observations
  88. GRB980326, optical observations
  89. GRB980326, optical observations
  90. GRB980329, Fading IR counterpart to radio source
  91. GRByymmdd, Announcement of automation
  92. GRB980326 IPN annulus
  93. GRB980329
  94. GRB980329 Keck K-band observations
  95. GRB980329 sub-millimeter observations
  96. GRB980329 IPN annulus
  97. GRB980329 optical observations
  98. GRB980329 near-IR observations
  99. GRB980329 optical observations
  100. GRB980326 optical observations

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