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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"

31727 results found.

  1. GRB981220
  2. GRB981220, Correction to GCN 179
  3. GRB981220, Optical Observations
  4. GRB 981220 Optical observations
  5. GRB 981226 Optical Observations
  6. GRB 980613: Spectroscopy of the host galaxy
  7. GRB981226, sub-millimeter observations
  8. GRB981220, sub-millimeter observations
  9. GRB 981220 and GRB 981226, optical observations
  10. GRB981226 Optical Observations
  11. GRB 981226 radio observations
  12. GRB 981226
  13. radio observations of GRB 981226
  14. GRB981220 B, R and I band observations
  15. Optical Observations of GRB981226
  16. GRB 981220:Optical Observations
  17. GRB 981220 optical R and I observations
  18. GRB981226, BeppoSAX Christmas GRB
  19. GRB 981226 - Infrared Observations
  20. GRB 981220
  21. GRB 981220, radio observations
  22. GRB 981220, radio observations
  23. GRB 981220: BeppoSAX/GRBM results
  24. GRB981220 I-band Observations
  25. GRB 981220
  26. GRB 981220 Optical Observations
  27. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  28. BeppoSAX NFI Observation of GRB980425
  29. GRB980425 Optical Follow-up
  30. GRB980425: X-ray revised positions
  31. GRB980703 Very Long Baseline Interferometry
  32. GRB970508 optical observations
  33. Optical Observations of the Host Galaxy of GRB 980519
  34. GRB980519, Optical Observations
  35. GRB980703, Host galaxy multicolor photometry
  36. GRB 980703 (NFI observations)
  37. GRB980703 optical photometry
  38. GRB 980703: BATSE Observations
  39. GRB980703 optical observations
  40. GRB980703: Radio transient
  41. GRB980703 H-band Observations
  42. GRB 980703: Spectrum of the proposed optical counterpart
  43. RXTE Observation of GRB 980706
  44. GRB980703: Spectrum of the proposed optical counterpart
  45. GRB980703 Transient Optical Follow-Up
  46. GRB980703: LOTIS observation at early times
  47. GRB980613 Optical Observations
  48. GRB 980703
  49. GRB980703 (I band observations)
  50. GRB 980703 H-band Observations
  51. GRB980703: radio source/optical transient
  52. BeppoSAX NFI observations of GRB 980703
  53. GRB980519 observation report
  54. Radio observations of SGRs
  55. GRB 980613 Near-IR observations
  56. GRB980613, optical observations
  57. GRB 980613: Optical transient and its host galaxy
  58. SGR1627-41, RXTE/ASM observations
  59. SGR1627-41, Refined IPN annulus location
  60. GRB 980613: Detection of the probable host galaxy
  61. Reduced error box of SGR 1627-41
  62. SGR1627-41, BeppoSAX-GRBM detections
  63. GRB 980613 Optical Observations
  64. GRB 980613 optical observations
  65. GRB980613 Optical Observations
  66. GRB980613 observations from Palomar
  67. GRB 980613 new optical/IR observations
  68. GRB971214 Secondary Standards
  69. GRB980519 Secondary Standards
  70. SGR1900+14
  71. GRB 980519 Optical Observations
  72. GRB980519 optical observations
  73. GRB980519 I-band observations
  74. GRB 980519
  75. GRB980519 optical observations
  76. GRB 980519 Optical Observations
  77. GRB980519 BATSE Observations
  78. GRB970519, optical follow-up at Schmidt Calern
  79. GRB980519 optical observations
  80. GRB980519 Optical Observations
  81. GRB980519 Optical Observations
  82. GRB980519 IPN POSITION
  83. GRB980519 Optical Observations
  84. GRB 980519 Optical Observations
  85. GRB980519 optical observations
  86. GRB980515, BeppoSAX IAUC to be submitted
  87. GRB980519, BeppoSAX-WFC updated position
  88. GRB 980425 Radio Light Curve
  89. GRB 980425 Brightness Temperature
  90. BSAX Observations of GRB980425 field
  91. IPN web site of GRBs
  92. GRB980425 BATSE observations
  93. SAX J0840.7+2248 Optical Observations
  94. GRB 980425 optical observations
  95. GRB980425: optical obs.
  96. GRB980425: Radio Observations
  97. GRB 980425 optical observations
  98. GRB980326, optical observations
  99. GRB980326, optical observations
  100. GRB980329, Fading IR counterpart to radio source

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