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

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