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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"
  1. GRB980519, Optical Observations
  2. GRB980703, Host galaxy multicolor photometry
  3. GRB980703 - BeppoSAX/GRBM detection
  4. GRB 980703 (NFI observations)
  5. GRB980703 optical photometry
  6. GRB 980703: BATSE Observations
  7. GRB980703 optical observations
  8. GRB980703: Radio transient
  9. GRB980703 H-band Observations
  10. GRB 980703: Spectrum of the proposed optical counterpart
  11. RXTE Observation of GRB 980706
  12. GRB980703: Spectrum of the proposed optical counterpart
  13. GRB980703 Transient Optical Follow-Up
  14. GRB980703: LOTIS observation at early times
  15. GRB980613 Optical Observations
  16. GRB 980703
  17. GRB980703 (I band observations)
  18. GRB 980703 H-band Observations
  19. GRB980703 (optical R observations)
  20. GRB980706
  21. GRB980703: radio source/optical transient
  22. BeppoSAX NFI observations of GRB 980703
  23. GRB 980703: ASM Position & Intensity
  24. GRB980703
  25. GRB980519 observation report
  26. GRB980703 optical followup
  27. SGR1627-41
  28. Radio observations of SGRs
  29. SGR1900+14 field optical observations
  30. GRB 980613 Near-IR observations
  31. GRB980613, optical observations
  32. GRB 980613: Optical transient and its host galaxy
  33. SGR1627-41, RXTE/ASM observations
  34. SGR1627-41, Refined IPN annulus location
  35. GRB 980613: Detection of the probable host galaxy
  36. Reduced error box of SGR 1627-41
  37. GRB 980613: BATSE Observations
  38. SGR1627-41, BeppoSAX-GRBM detections
  39. SGR 1627-41
  40. GRB 980613 Optical Observations
  41. GRB 980613 optical observations
  42. Discovery of a new SGR source, SGR1627-41
  43. GRB980613 Optical Observations
  44. GRB980613 observations from Palomar
  45. GRB980613 BeppoSAX-NFI follow up
  46. GRB 980613 new optical/IR observations
  47. GRB 980613 optical/IR obs.
  48. GRB980613 Near Infra-Red Observations
  49. GRB980611
  50. GRB980613, BeppoSAX WFC positions
  51. GRB971214 Secondary Standards
  52. SGR 1900+14
  53. GRB980519 Secondary Standards
  54. SGR1900+14
  55. SGR1900+14
  56. BATSE on-board GRB trigger change
  57. GRB 980519 Optical Observations
  58. GRB980519 optical observations
  59. GRB980519 I-band observations
  60. GRB 980519
  61. GRB980519 optical observations
  62. GRB 980519 Optical Observations
  63. GRB980519 BATSE Observations
  64. GRB970519, optical follow-up at Schmidt Calern
  65. GRB980519 optical observations
  66. GRB980519 Optical Observations
  67. GRB980519 Optical Observations
  68. GRB980519 IPN POSITION
  69. GRB980519 Optical Observations
  70. GRB 980519 Optical Observations
  71. GRB980519 optical observations
  72. GRB980515, BeppoSAX IAUC to be submitted
  73. BATSE on-board GRB trigger change
  74. GRB980519, BeppoSAX-WFC updated position
  75. GRB980519, BeppoSAX-WFC position
  76. GRB980515: SAX-WFC updated position
  77. BeppoSAX GRB ALERT: updated position of grb980515
  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. report on BSAX observations of GRB980425
  89. GRB 980425 optical observations
  90. GRB 980329 ROSAT observation
  91. GRB980326 X-ray Observations
  92. GRB980326, optical observations
  93. GRB980326, optical observations
  94. GRB980329, Fading IR counterpart to radio source
  95. GRByymmdd, Announcement of automation
  96. GRB980326 IPN annulus
  97. GRB980329
  98. GRB980329 Keck K-band observations
  99. GRB980329 sub-millimeter observations
  100. GRB980329 IPN annulus

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