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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. GRB980329 R,I flux calibration and R,I,K upper limits
  2. GRB980425 Optical Follow-up
  3. GRB980425: X-ray revised positions
  4. GRB 980923 BATSE Observations
  5. SGR1900+14, BeppoSAX-GRBM observations
  6. GRB980703 Very Long Baseline Interferometry
  7. GRB970508 optical observations
  8. GRB971214, association with a Galactic star?
  9. Optical Observations of the Host Galaxy of GRB 980519
  10. GRB980519, Optical Observations
  11. GRB980703, Host galaxy multicolor photometry
  12. GRB980703 - BeppoSAX/GRBM detection
  13. GRB 980703 (NFI observations)
  14. GRB980703 optical photometry
  15. GRB 980703: BATSE Observations
  16. GRB980703 optical observations
  17. GRB980703: Radio transient
  18. GRB980703 H-band Observations
  19. GRB 980703: Spectrum of the proposed optical counterpart
  20. RXTE Observation of GRB 980706
  21. GRB980703: Spectrum of the proposed optical counterpart
  22. GRB980703 Transient Optical Follow-Up
  23. GRB980703: LOTIS observation at early times
  24. GRB980613 Optical Observations
  25. GRB 980703
  26. GRB980703 (I band observations)
  27. GRB 980703 H-band Observations
  28. GRB980703 (optical R observations)
  29. GRB980706
  30. GRB980703: radio source/optical transient
  31. BeppoSAX NFI observations of GRB 980703
  32. GRB 980703: ASM Position & Intensity
  33. GRB980703
  34. GRB980519 observation report
  35. GRB980703 optical followup
  36. SGR1627-41
  37. Radio observations of SGRs
  38. SGR1900+14 field optical observations
  39. GRB 980613 Near-IR observations
  40. GRB980613, optical observations
  41. GRB 980613: Optical transient and its host galaxy
  42. SGR1627-41, RXTE/ASM observations
  43. SGR1627-41, Refined IPN annulus location
  44. GRB 980613: Detection of the probable host galaxy
  45. Reduced error box of SGR 1627-41
  46. GRB 980613: BATSE Observations
  47. SGR1627-41, BeppoSAX-GRBM detections
  48. SGR 1627-41
  49. GRB 980613 Optical Observations
  50. GRB 980613 optical observations
  51. Discovery of a new SGR source, SGR1627-41
  52. GRB980613 Optical Observations
  53. GRB980613 observations from Palomar
  54. GRB980613 BeppoSAX-NFI follow up
  55. GRB 980613 new optical/IR observations
  56. GRB 980613 optical/IR obs.
  57. GRB980613 Near Infra-Red Observations
  58. GRB980611
  59. GRB980613, BeppoSAX WFC positions
  60. GRB971214 Secondary Standards
  61. SGR 1900+14
  62. GRB980519 Secondary Standards
  63. SGR1900+14
  64. SGR1900+14
  65. BATSE on-board GRB trigger change
  66. GRB 980519 Optical Observations
  67. GRB980519 optical observations
  68. GRB980519 I-band observations
  69. GRB 980519
  70. GRB980519 optical observations
  71. GRB 980519 Optical Observations
  72. GRB980519 BATSE Observations
  73. GRB970519, optical follow-up at Schmidt Calern
  74. GRB980519 optical observations
  75. GRB980519 Optical Observations
  76. GRB980519 Optical Observations
  77. GRB980519 IPN POSITION
  78. GRB980519 Optical Observations
  79. GRB 980519 Optical Observations
  80. GRB980519 optical observations
  81. GRB980515, BeppoSAX IAUC to be submitted
  82. BATSE on-board GRB trigger change
  83. GRB980519, BeppoSAX-WFC updated position
  84. GRB980519, BeppoSAX-WFC position
  85. GRB980515: SAX-WFC updated position
  86. BeppoSAX GRB ALERT: updated position of grb980515
  87. GRB 980425 Radio Light Curve
  88. GRB 980425 Brightness Temperature
  89. BSAX Observations of GRB980425 field
  90. IPN web site of GRBs
  91. GRB980425 BATSE observations
  92. SAX J0840.7+2248 Optical Observations
  93. GRB 980425 optical observations
  94. GRB980425: optical obs.
  95. GRB980425: Radio Observations
  96. GRB 980425 optical observations
  97. report on BSAX observations of GRB980425
  98. GRB 980425 optical observations
  99. GRB 980329 ROSAT observation
  100. GRB980326 X-ray Observations

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