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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 980613: BATSE Observations
  2. SGR1627-41, BeppoSAX-GRBM detections
  3. SGR 1627-41
  4. GRB 980613 Optical Observations
  5. GRB 980613 optical observations
  6. Discovery of a new SGR source, SGR1627-41
  7. GRB980613 Optical Observations
  8. GRB980613 observations from Palomar
  9. GRB980613 BeppoSAX-NFI follow up
  10. GRB 980613 new optical/IR observations
  11. GRB 980613 optical/IR obs.
  12. GRB980613 Near Infra-Red Observations
  13. GRB980611
  14. GRB980613, BeppoSAX WFC positions
  15. GRB971214 Secondary Standards
  16. SGR 1900+14
  17. GRB980519 Secondary Standards
  18. SGR1900+14
  19. SGR1900+14
  20. BATSE on-board GRB trigger change
  21. GRB 980519 Optical Observations
  22. GRB980519 optical observations
  23. GRB980519 I-band observations
  24. GRB 980519
  25. GRB980519 optical observations
  26. GRB 980519 Optical Observations
  27. GRB980519 BATSE Observations
  28. GRB970519, optical follow-up at Schmidt Calern
  29. GRB980519 optical observations
  30. GRB980519 Optical Observations
  31. GRB980519 Optical Observations
  32. GRB980519 IPN POSITION
  33. GRB980519 Optical Observations
  34. GRB 980519 Optical Observations
  35. GRB980519 optical observations
  36. GRB980515, BeppoSAX IAUC to be submitted
  37. BATSE on-board GRB trigger change
  38. GRB980519, BeppoSAX-WFC updated position
  39. GRB980519, BeppoSAX-WFC position
  40. GRB980515: SAX-WFC updated position
  41. BeppoSAX GRB ALERT: updated position of grb980515
  42. GRB 980425 Radio Light Curve
  43. GRB 980425 Brightness Temperature
  44. BSAX Observations of GRB980425 field
  45. IPN web site of GRBs
  46. GRB980425 BATSE observations
  47. SAX J0840.7+2248 Optical Observations
  48. GRB 980425 optical observations
  49. GRB980425: optical obs.
  50. GRB980425: Radio Observations
  51. GRB 980425 optical observations
  52. report on BSAX observations of GRB980425
  53. GRB 980425 optical observations
  54. GRB 980329 ROSAT observation
  55. GRB980326 X-ray Observations
  56. GRB980326, optical observations
  57. GRB980326, optical observations
  58. GRB980329, Fading IR counterpart to radio source
  59. GRByymmdd, Announcement of automation
  60. GRB980326 IPN annulus
  61. GRB980329
  62. GRB980329 Keck K-band observations
  63. GRB980329 sub-millimeter observations
  64. GRB980329 IPN annulus
  65. GRB980329 optical observations
  66. GRB980329 near-IR observations
  67. GRB980329 near-IR observations
  68. GRB980329 optical observations
  69. GRB980329 infrared observations
  70. GRB980329 optical observations
  71. GRB980326 optical observations
  72. GRB980329 optical observations
  73. GRB980329 VLA observations
  74. GRB980329 near IR observations
  75. GRB980329 optical observations
  76. GRB980329 optical observations
  77. GRB980329 optical observations
  78. GRB980326 optical observations
  79. GRB980326 optical observations
  80. GRB980326 optical observations
  81. GRB980326 optical observations
  82. GRB970508 SAO RAS optical observations
  83. Optical Observations of GRB 970508
  84. GRB 971214: Redshift from Keck Observations
  85. Near-IR follow-up on GRB 971227
  86. GRB971214: Keck R & I-band Observations
  87. GRB 971227: Optical Observations
  88. Optical Observations of the GRB 971227 field
  89. Optical Observations on GRB 971227
  90. GRB971227: Plaskett R-band observations
  91. GRB 971227: Optical clarifications
  92. Optical Observations for GRB 971227
  93. GRB971227: Further CAHA R-band images
  94. GRB971227: LOTIS observations
  95. GRB 971227: CAHA R-band images
  96. GRB 971227: Optical observations
  97. GRB971214: Optical Observations and Calibrations
  98. Sub-millimeter Observations of GRB 971214 at the JCMT
  99. GRB 971214: EUVE Observations
  100. GRB 971214: Redshift from Keck Optical Observations

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