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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. GRB981226 Optical Observation
  2. GRB 981220, radio observations
  3. GRB 981220: BeppoSAX/GRBM results
  4. GRB981220 I-band Observations
  5. GRB981220 Optical Observations
  6. GRB 981220
  7. GRB 981220 Optical Observations
  8. GRB 981220, optical observations
  9. GRB 980326/Host Galaxy
  10. GRB981220 IPN error box
  11. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  12. BeppoSAX NFI Observation of GRB980425
  13. GRB980329 R,I flux calibration and R,I,K upper limits
  14. GRB980425 Optical Follow-up
  15. GRB980425: X-ray revised positions
  16. GRB 980923 BATSE Observations
  17. SGR1900+14, BeppoSAX-GRBM observations
  18. GRB980703 Very Long Baseline Interferometry
  19. GRB970508 optical observations
  20. GRB971214, association with a Galactic star?
  21. Optical Observations of the Host Galaxy of GRB 980519
  22. GRB980519, Optical Observations
  23. GRB980703, Host galaxy multicolor photometry
  24. GRB980703 - BeppoSAX/GRBM detection
  25. GRB 980703 (NFI observations)
  26. GRB980703 optical photometry
  27. GRB 980703: BATSE Observations
  28. GRB980703 optical observations
  29. GRB980703: Radio transient
  30. GRB980703 H-band Observations
  31. GRB 980703: Spectrum of the proposed optical counterpart
  32. RXTE Observation of GRB 980706
  33. GRB980703: Spectrum of the proposed optical counterpart
  34. GRB980703 Transient Optical Follow-Up
  35. GRB980703: LOTIS observation at early times
  36. GRB980613 Optical Observations
  37. GRB 980703
  38. GRB980703 (I band observations)
  39. GRB 980703 H-band Observations
  40. GRB980703 (optical R observations)
  41. GRB980706
  42. GRB980703: radio source/optical transient
  43. BeppoSAX NFI observations of GRB 980703
  44. GRB 980703: ASM Position & Intensity
  45. GRB980703
  46. GRB980519 observation report
  47. GRB980703 optical followup
  48. SGR1627-41
  49. Radio observations of SGRs
  50. SGR1900+14 field optical observations
  51. GRB 980613 Near-IR observations
  52. GRB980613, optical observations
  53. GRB 980613: Optical transient and its host galaxy
  54. SGR1627-41, RXTE/ASM observations
  55. SGR1627-41, Refined IPN annulus location
  56. GRB 980613: Detection of the probable host galaxy
  57. Reduced error box of SGR 1627-41
  58. GRB 980613: BATSE Observations
  59. SGR1627-41, BeppoSAX-GRBM detections
  60. SGR 1627-41
  61. GRB 980613 Optical Observations
  62. GRB 980613 optical observations
  63. Discovery of a new SGR source, SGR1627-41
  64. GRB980613 Optical Observations
  65. GRB980613 observations from Palomar
  66. GRB980613 BeppoSAX-NFI follow up
  67. GRB 980613 new optical/IR observations
  68. GRB 980613 optical/IR obs.
  69. GRB980613 Near Infra-Red Observations
  70. GRB980611
  71. GRB980613, BeppoSAX WFC positions
  72. GRB971214 Secondary Standards
  73. SGR 1900+14
  74. GRB980519 Secondary Standards
  75. SGR1900+14
  76. SGR1900+14
  77. BATSE on-board GRB trigger change
  78. GRB 980519 Optical Observations
  79. GRB980519 optical observations
  80. GRB980519 I-band observations
  81. GRB 980519
  82. GRB980519 optical observations
  83. GRB 980519 Optical Observations
  84. GRB980519 BATSE Observations
  85. GRB970519, optical follow-up at Schmidt Calern
  86. GRB980519 optical observations
  87. GRB980519 Optical Observations
  88. GRB980519 Optical Observations
  89. GRB980519 IPN POSITION
  90. GRB980519 Optical Observations
  91. GRB 980519 Optical Observations
  92. GRB980519 optical observations
  93. GRB980515, BeppoSAX IAUC to be submitted
  94. BATSE on-board GRB trigger change
  95. GRB980519, BeppoSAX-WFC updated position
  96. GRB980519, BeppoSAX-WFC position
  97. GRB980515: SAX-WFC updated position
  98. BeppoSAX GRB ALERT: updated position of grb980515
  99. GRB 980425 Radio Light Curve
  100. GRB 980425 Brightness Temperature

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