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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"

45452 results found.

  1. IPN triangulation of GRB010613
  2. IPN triangulation of GRB010612
  3. IPN triangulation of GRB010612
  4. HETE Fully-Automated GCN Notices
  5. GRB000301C: Late-time HST/STIS observation
  6. GRB010518: a faint BeppoSAX detection
  7. GRB000418: HST/STIS Second-epoch Observations
  8. X-ray precursors to the large flare from SGR 1900+14
  9. GRB010214, optical observations
  10. GRB010427, Gamma Ray Observations
  11. SGR 1900+14: No evidence of extended X-ray emission
  12. SGR 1900+14 : RXTE observations
  13. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  14. SGR1900+14
  15. SGR 1900+14: Correction to GCN 1049
  16. GRB 010222 /corrections to VBT data
  17. Millimeter observation of SGR 1900+14
  18. SGR 1900+14: Detection of extended X-ray emission
  19. Chandra Observations of SGR 1900+14
  20. SGR 1900+14, Chandra observations
  21. Chandra Observations of SGR 1900+14
  22. Possible precursor to the SGR1900+14 giant burst
  23. SGR1900+14, I-band observations
  24. IPN Triangulation of the Giant Flare from SGR1900+14
  25. GRB010412, field photometry
  26. Giant flare from SGR1900+14
  27. GRB 010326b Optical Observations
  28. GRB010412: Optical observations
  29. GRB010412: Optical observations
  30. GRB010412: BeppoSAX GRBM and WFC observations
  31. IPN Triangulation of GRB010412
  32. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  33. BeppoSAX GRB ALERT: GRB010412
  34. GRB Observation Report
  35. GRB010324, revised field photometry
  36. REVISED LOCATION OF GRB010326A
  37. GRB 980326: Late-time HST/STIS observations
  38. GRB010324, field photometry
  39. GRB010326B, field photometry
  40. GRB010326, field photometry
  41. GRB010220, field photometry
  42. Further Optical Observations of GRB 010324
  43. GRB010222, CXO X-ray observations
  44. GRB 010326A: Further optical observations
  45. GRB010324: BeppoSAX/GRBM data
  46. GRB 010326B: Optical observations
  47. GRB010324, optical observations
  48. GRB010326B: Localization by HETE (2nd GRB for this date)
  49. GRB 010326: Optical observations
  50. GRB 010326 optical observations
  51. GRB010326: Refined Localization by HETE
  52. GRB010326: Localization by HETE
  53. Duration, ECT, peak flux and fluence of GRB010324
  54. Optical Observations of GRB 010324
  55. IPN TRIANGULATION OF GRB010324
  56. GRB990705, VLT-FORS1 observations of the host galaxy
  57. GRB010222, late-time optical observation
  58. Support extension to the BeppoSAX mission
  59. GRB 010222 - HEGRA GeV/TeV Observations
  60. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  61. GRB010222: Chandra X-ray Observatory Observation
  62. GRB010222: Sub-millimeter vanishing act
  63. GRB010222 - Optical observation
  64. GRB 010222, Optical Observations
  65. GRB010220 optical obsercations
  66. GRB010222 - Optical observation
  67. GRB 010222: High-Resolution Keck Spectroscopy
  68. GRB010222: Optical observation and decay
  69. GRB 010214, I-band data
  70. Sub-millimeter Excess/GRB 010222
  71. GRB 010222
  72. GRB 010222 HST/Chandra TOO
  73. GRB 010222
  74. GRB010222 further R-band photometry
  75. GRB010222: R-band data
  76. GRB010222 Optical observations
  77. GRB 010222: Keck Spectroscopy
  78. GRB010214, field photometry
  79. GRB010222, field photometry
  80. GRB010222 further R-band photometry
  81. GRB010222, possible increase of optical decay slope
  82. GRB 010222 Kyoto optical observation
  83. GRB010222: fading behavior
  84. GRB 010222 BV optical observations
  85. GRB010220, Optical Observations
  86. GRB010222 R-BAND OBSERVATION
  87. GRB 010220: Near-IR Observations
  88. GRB010214 follow-up from Hanle
  89. GRB 010222: Near-IR Observations
  90. GRB 010222: Optical Observations
  91. GRB 010222, Decay Slope Confirmed
  92. GRB010222: Another absorption line system
  93. GRB010222: Optical decay slope
  94. GRB 010214, Optical Observations
  95. GRB010222: Sub-millimeter detection
  96. GRB010222: R-band fading behavior
  97. GRB010222: Optical Observations
  98. GRB010222, radio observations
  99. GRB010222, optical observations
  100. GRB010222: BeppoSAX/NFI Observations

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