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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"

41619 results found.

  1. GRB980703 optical followup
  2. Radio observations of SGRs
  3. SGR1900+14 field optical observations
  4. GRB 980613 Near-IR observations
  5. GRB980613, optical observations
  6. GRB 980613: Optical transient and its host galaxy
  7. SGR1627-41, RXTE/ASM observations
  8. GRB 980613: Detection of the probable host galaxy
  9. Reduced error box of SGR 1627-41
  10. GRB 980613: BATSE Observations
  11. SGR1627-41, BeppoSAX-GRBM detections
  12. SGR 1627-41
  13. GRB 980613 Optical Observations
  14. GRB 980613 optical observations
  15. Discovery of a new SGR source, SGR1627-41
  16. GRB980613 Optical Observations
  17. GRB980613 observations from Palomar
  18. GRB980613 BeppoSAX-NFI follow up
  19. GRB 980613 new optical/IR observations
  20. GRB 980613 optical/IR obs.
  21. GRB980613 Near Infra-Red Observations
  22. GRB980613, BeppoSAX WFC positions
  23. GRB971214 Secondary Standards
  24. SGR 1900+14
  25. GRB980519 Secondary Standards
  26. SGR1900+14
  27. SGR1900+14
  28. GRB 980519 Optical Observations
  29. GRB980519 optical observations
  30. GRB980519 I-band observations
  31. GRB 980519
  32. GRB980519 optical observations
  33. GRB 980519 Optical Observations
  34. GRB980519 BATSE Observations
  35. GRB970519, optical follow-up at Schmidt Calern
  36. GRB980519 optical observations
  37. GRB980519 Optical Observations
  38. GRB980519 Optical Observations
  39. GRB980519 IPN POSITION
  40. GRB980519 Optical Observations
  41. GRB 980519 Optical Observations
  42. GRB980519 optical observations
  43. GRB980515, BeppoSAX IAUC to be submitted
  44. GRB980519, BeppoSAX-WFC updated position
  45. GRB980519, BeppoSAX-WFC position
  46. BeppoSAX GRB ALERT: updated position of grb980515
  47. GRB 980425 Radio Light Curve
  48. GRB 980425 Brightness Temperature
  49. BSAX Observations of GRB980425 field
  50. GRB980425 BATSE observations
  51. SAX J0840.7+2248 Optical Observations
  52. GRB 980425 optical observations
  53. GRB980425: optical obs.
  54. GRB980425: Radio Observations
  55. GRB 980425 optical observations
  56. report on BSAX observations of GRB980425
  57. GRB 980425 optical observations
  58. GRB 980329 ROSAT observation
  59. GRB980326 X-ray Observations
  60. GRB980326, optical observations
  61. GRB980326, optical observations
  62. GRB980329, Fading IR counterpart to radio source
  63. GRByymmdd, Announcement of automation
  64. GRB980329
  65. GRB980329 Keck K-band observations
  66. GRB980329 sub-millimeter observations
  67. GRB980329 optical observations
  68. GRB980329 near-IR observations
  69. GRB980329 near-IR observations
  70. GRB980329 optical observations
  71. GRB980329 infrared observations
  72. GRB980329 optical observations
  73. GRB980326 optical observations
  74. GRB980329 optical observations
  75. GRB980329 VLA observations
  76. GRB980329 near IR observations
  77. GRB980329 optical observations
  78. GRB980329 optical observations
  79. GRB980329 optical observations
  80. GRB980326 optical observations
  81. GRB980326 optical observations
  82. GRB980326 optical observations
  83. GRB980326 optical observations
  84. GRB970508 SAO RAS optical observations
  85. Optical Observations of GRB 970508
  86. GRB 971214: Redshift from Keck Observations
  87. Near-IR follow-up on GRB 971227
  88. GRB971214: Keck R & I-band Observations
  89. GRB 971227: Optical Observations
  90. Optical Observations of the GRB 971227 field
  91. Optical Observations on GRB 971227
  92. GRB971227: Plaskett R-band observations
  93. GRB 971227: Optical clarifications
  94. Optical Observations for GRB 971227
  95. GRB971227: Further CAHA R-band images
  96. GRB971227: LOTIS observations
  97. GRB 971227: CAHA R-band images
  98. GRB 971227: Optical observations
  99. GRB971214: Optical Observations and Calibrations
  100. Sub-millimeter Observations of GRB 971214 at the JCMT

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