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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"

45465 results found.

  1. GRB 010629 Optical Observations
  2. GRB010629: Optical Observations
  3. SGR1900+14: High Fluence Burst Localized by HETE
  4. GRB010629, optical observations
  5. IPN triangulation of GRB010629
  6. GRB010629: A Burst Localized by HETE
  7. SGR1900+14: Second Burst Localized by HETE
  8. SGR1900+14: A Burst Localized by HETE
  9. Possible burst from SGR1806-20
  10. IPN detection of SGR1900+14
  11. SGR1806-20: A Second, Intense Burst Localized by HETE
  12. GRB 00630: Host Galaxy
  13. SGR1806-20: Localization by HETE
  14. IPN triangulation of GRB010613
  15. IPN triangulation of GRB010612
  16. IPN triangulation of GRB010612
  17. HETE Fully-Automated GCN Notices
  18. GRB000301C: Late-time HST/STIS observation
  19. GRB010518: a faint BeppoSAX detection
  20. GRB000418: HST/STIS Second-epoch Observations
  21. X-ray precursors to the large flare from SGR 1900+14
  22. GRB010214, optical observations
  23. GRB010427, Gamma Ray Observations
  24. SGR 1900+14: No evidence of extended X-ray emission
  25. SGR 1900+14 : RXTE observations
  26. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  27. SGR1900+14
  28. SGR 1900+14: Correction to GCN 1049
  29. GRB 010222 /corrections to VBT data
  30. Millimeter observation of SGR 1900+14
  31. SGR 1900+14: Detection of extended X-ray emission
  32. Chandra Observations of SGR 1900+14
  33. SGR 1900+14, Chandra observations
  34. Chandra Observations of SGR 1900+14
  35. Possible precursor to the SGR1900+14 giant burst
  36. SGR1900+14, I-band observations
  37. IPN Triangulation of the Giant Flare from SGR1900+14
  38. GRB010412, field photometry
  39. Giant flare from SGR1900+14
  40. GRB 010326b Optical Observations
  41. GRB010412: Optical observations
  42. GRB010412: Optical observations
  43. GRB010412: BeppoSAX GRBM and WFC observations
  44. IPN Triangulation of GRB010412
  45. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  46. BeppoSAX GRB ALERT: GRB010412
  47. GRB Observation Report
  48. GRB010324, revised field photometry
  49. REVISED LOCATION OF GRB010326A
  50. GRB 980326: Late-time HST/STIS observations
  51. GRB010324, field photometry
  52. GRB010326B, field photometry
  53. GRB010326, field photometry
  54. GRB010220, field photometry
  55. Further Optical Observations of GRB 010324
  56. GRB010222, CXO X-ray observations
  57. GRB 010326A: Further optical observations
  58. GRB010324: BeppoSAX/GRBM data
  59. GRB 010326B: Optical observations
  60. GRB010324, optical observations
  61. GRB010326B: Localization by HETE (2nd GRB for this date)
  62. GRB 010326: Optical observations
  63. GRB 010326 optical observations
  64. GRB010326: Refined Localization by HETE
  65. GRB010326: Localization by HETE
  66. Duration, ECT, peak flux and fluence of GRB010324
  67. Optical Observations of GRB 010324
  68. IPN TRIANGULATION OF GRB010324
  69. GRB990705, VLT-FORS1 observations of the host galaxy
  70. GRB010222, late-time optical observation
  71. Support extension to the BeppoSAX mission
  72. GRB 010222 - HEGRA GeV/TeV Observations
  73. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  74. GRB010222: Chandra X-ray Observatory Observation
  75. GRB010222: Sub-millimeter vanishing act
  76. GRB010222 - Optical observation
  77. GRB 010222, Optical Observations
  78. GRB010220 optical obsercations
  79. GRB010222 - Optical observation
  80. GRB 010222: High-Resolution Keck Spectroscopy
  81. GRB010222: Optical observation and decay
  82. GRB 010214, I-band data
  83. Sub-millimeter Excess/GRB 010222
  84. GRB 010222
  85. GRB 010222 HST/Chandra TOO
  86. GRB 010222
  87. GRB010222 further R-band photometry
  88. GRB010222: R-band data
  89. GRB010222 Optical observations
  90. GRB 010222: Keck Spectroscopy
  91. GRB010214, field photometry
  92. GRB010222, field photometry
  93. GRB010222 further R-band photometry
  94. GRB010222, possible increase of optical decay slope
  95. GRB 010222 Kyoto optical observation
  96. GRB010222: fading behavior
  97. GRB 010222 BV optical observations
  98. GRB010220, Optical Observations
  99. GRB010222 R-BAND OBSERVATION
  100. GRB 010220: Near-IR Observations

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