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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"

40633 results found.

  1. GRB 980703: Spectrum of the proposed optical counterpart
  2. RXTE Observation of GRB 980706
  3. GRB980703: Spectrum of the proposed optical counterpart
  4. GRB980703 Transient Optical Follow-Up
  5. GRB980703: LOTIS observation at early times
  6. GRB980613 Optical Observations
  7. GRB 980703
  8. GRB980703 (I band observations)
  9. GRB 980703 H-band Observations
  10. GRB980703 (optical R observations)
  11. GRB980703: radio source/optical transient
  12. BeppoSAX NFI observations of GRB 980703
  13. GRB 980703: ASM Position & Intensity
  14. GRB980703
  15. GRB980703 optical followup
  16. Radio observations of SGRs
  17. SGR1900+14 field optical observations
  18. GRB 980613 Near-IR observations
  19. GRB980613, optical observations
  20. GRB 980613: Optical transient and its host galaxy
  21. SGR1627-41, RXTE/ASM observations
  22. GRB 980613: Detection of the probable host galaxy
  23. Reduced error box of SGR 1627-41
  24. GRB 980613: BATSE Observations
  25. SGR1627-41, BeppoSAX-GRBM detections
  26. SGR 1627-41
  27. GRB 980613 Optical Observations
  28. GRB 980613 optical observations
  29. Discovery of a new SGR source, SGR1627-41
  30. GRB980613 Optical Observations
  31. GRB980613 observations from Palomar
  32. GRB980613 BeppoSAX-NFI follow up
  33. GRB 980613 new optical/IR observations
  34. GRB 980613 optical/IR obs.
  35. GRB980613 Near Infra-Red Observations
  36. GRB980613, BeppoSAX WFC positions
  37. GRB971214 Secondary Standards
  38. SGR 1900+14
  39. GRB980519 Secondary Standards
  40. SGR1900+14
  41. SGR1900+14
  42. GRB 980519 Optical Observations
  43. GRB980519 optical observations
  44. GRB980519 I-band observations
  45. GRB 980519
  46. GRB980519 optical observations
  47. GRB 980519 Optical Observations
  48. GRB980519 BATSE Observations
  49. GRB970519, optical follow-up at Schmidt Calern
  50. GRB980519 optical observations
  51. GRB980519 Optical Observations
  52. GRB980519 Optical Observations
  53. GRB980519 IPN POSITION
  54. GRB980519 Optical Observations
  55. GRB 980519 Optical Observations
  56. GRB980519 optical observations
  57. GRB980515, BeppoSAX IAUC to be submitted
  58. GRB980519, BeppoSAX-WFC updated position
  59. GRB980519, BeppoSAX-WFC position
  60. BeppoSAX GRB ALERT: updated position of grb980515
  61. GRB 980425 Radio Light Curve
  62. GRB 980425 Brightness Temperature
  63. BSAX Observations of GRB980425 field
  64. GRB980425 BATSE observations
  65. SAX J0840.7+2248 Optical Observations
  66. GRB 980425 optical observations
  67. GRB980425: optical obs.
  68. GRB980425: Radio Observations
  69. GRB 980425 optical observations
  70. report on BSAX observations of GRB980425
  71. GRB 980425 optical observations
  72. GRB 980329 ROSAT observation
  73. GRB980326 X-ray Observations
  74. GRB980326, optical observations
  75. GRB980326, optical observations
  76. GRB980329, Fading IR counterpart to radio source
  77. GRByymmdd, Announcement of automation
  78. GRB980329
  79. GRB980329 Keck K-band observations
  80. GRB980329 sub-millimeter observations
  81. GRB980329 optical observations
  82. GRB980329 near-IR observations
  83. GRB980329 near-IR observations
  84. GRB980329 optical observations
  85. GRB980329 infrared observations
  86. GRB980329 optical observations
  87. GRB980326 optical observations
  88. GRB980329 optical observations
  89. GRB980329 VLA observations
  90. GRB980329 near IR observations
  91. GRB980329 optical observations
  92. GRB980329 optical observations
  93. GRB980329 optical observations
  94. GRB980326 optical observations
  95. GRB980326 optical observations
  96. GRB980326 optical observations
  97. GRB980326 optical observations
  98. GRB970508 SAO RAS optical observations
  99. Optical Observations of GRB 970508
  100. GRB 971214: Redshift from Keck Observations

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