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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 Observations
  2. GRB981226 BeppoSAX follow up
  3. GRB 981226 radio observations
  4. GRB 981226
  5. GRB 981226 optical observations
  6. radio observations of GRB 981226
  7. GRB981220 B, R and I band observations
  8. GRB981226, BeppoSAX-NFI follow-up
  9. Optical Observations of GRB981226
  10. GRB 981220:Optical Observations
  11. GRB 981220 optical R and I observations
  12. GRB981226, BeppoSAX Christmas GRB
  13. GRB 981226 - Infrared Observations
  14. GRB 981226 optical observations
  15. GRB 981220
  16. GRB 981220, radio observations
  17. GRB981226 Optical Observation
  18. GRB 981220, radio observations
  19. GRB 981220: BeppoSAX/GRBM results
  20. GRB981220 I-band Observations
  21. GRB981220 Optical Observations
  22. GRB 981220
  23. GRB 981220 Optical Observations
  24. GRB 981220, optical observations
  25. GRB 980326/Host Galaxy
  26. GRB981220 IPN error box
  27. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  28. BeppoSAX NFI Observation of GRB980425
  29. GRB980329 R,I flux calibration and R,I,K upper limits
  30. GRB980425 Optical Follow-up
  31. GRB980425: X-ray revised positions
  32. GRB 980923 BATSE Observations
  33. SGR1900+14, BeppoSAX-GRBM observations
  34. GRB980703 Very Long Baseline Interferometry
  35. GRB970508 optical observations
  36. GRB971214, association with a Galactic star?
  37. Optical Observations of the Host Galaxy of GRB 980519
  38. GRB980519, Optical Observations
  39. GRB980703, Host galaxy multicolor photometry
  40. GRB980703 - BeppoSAX/GRBM detection
  41. GRB 980703 (NFI observations)
  42. GRB980703 optical photometry
  43. GRB 980703: BATSE Observations
  44. GRB980703 optical observations
  45. GRB980703: Radio transient
  46. GRB980703 H-band Observations
  47. GRB 980703: Spectrum of the proposed optical counterpart
  48. RXTE Observation of GRB 980706
  49. GRB980703: Spectrum of the proposed optical counterpart
  50. GRB980703 Transient Optical Follow-Up
  51. GRB980703: LOTIS observation at early times
  52. GRB980613 Optical Observations
  53. GRB 980703
  54. GRB980703 (I band observations)
  55. GRB 980703 H-band Observations
  56. GRB980703 (optical R observations)
  57. GRB980706
  58. GRB980703: radio source/optical transient
  59. BeppoSAX NFI observations of GRB 980703
  60. GRB 980703: ASM Position & Intensity
  61. GRB980703
  62. GRB980519 observation report
  63. GRB980703 optical followup
  64. SGR1627-41
  65. Radio observations of SGRs
  66. SGR1900+14 field optical observations
  67. GRB 980613 Near-IR observations
  68. GRB980613, optical observations
  69. GRB 980613: Optical transient and its host galaxy
  70. SGR1627-41, RXTE/ASM observations
  71. SGR1627-41, Refined IPN annulus location
  72. GRB 980613: Detection of the probable host galaxy
  73. Reduced error box of SGR 1627-41
  74. GRB 980613: BATSE Observations
  75. SGR1627-41, BeppoSAX-GRBM detections
  76. SGR 1627-41
  77. GRB 980613 Optical Observations
  78. GRB 980613 optical observations
  79. Discovery of a new SGR source, SGR1627-41
  80. GRB980613 Optical Observations
  81. GRB980613 observations from Palomar
  82. GRB980613 BeppoSAX-NFI follow up
  83. GRB 980613 new optical/IR observations
  84. GRB 980613 optical/IR obs.
  85. GRB980613 Near Infra-Red Observations
  86. GRB980611
  87. GRB980613, BeppoSAX WFC positions
  88. GRB971214 Secondary Standards
  89. SGR 1900+14
  90. GRB980519 Secondary Standards
  91. SGR1900+14
  92. SGR1900+14
  93. BATSE on-board GRB trigger change
  94. GRB 980519 Optical Observations
  95. GRB980519 optical observations
  96. GRB980519 I-band observations
  97. GRB 980519
  98. GRB980519 optical observations
  99. GRB 980519 Optical Observations
  100. GRB980519 BATSE Observations

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