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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"

41689 results found.

  1. SGR 1900+14 : RXTE observations
  2. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  3. SGR1900+14 - correction
  4. SGR1900+14
  5. SGR 1900+14: Correction to GCN 1049
  6. GRB 010222 /corrections to VBT data
  7. Millimeter observation of SGR 1900+14
  8. SGR 1900+14: Detection of extended X-ray emission
  9. SGR 1900+14, Chandra observations
  10. Chandra Observations of SGR 1900+14
  11. Possible precursor to the SGR1900+14 giant burst
  12. SGR1900+14, I-band observations
  13. IPN Triangulation of the Giant Flare from SGR1900+14
  14. GRB010412, field photometry
  15. Giant flare from SGR1900+14
  16. GRB 010326b Optical Observations
  17. GRB010412: Optical observations
  18. GRB010412: Optical observations
  19. GRB010412: BeppoSAX GRBM and WFC observations
  20. IPN Triangulation of GRB010412
  21. BeppoSAX GRB ALERT: GRB010412
  22. GRB010324, revised field photometry
  23. REVISED LOCATION OF GRB010326A
  24. GRB 980326: Late-time HST/STIS observations
  25. GRB010324, field photometry
  26. GRB010326B, field photometry
  27. GRB010326, field photometry
  28. GRB010220, field photometry
  29. Further Optical Observations of GRB 010324
  30. GRB010222, CXO X-ray observations
  31. GRB 010326A: Further optical observations
  32. GRB010324: BeppoSAX/GRBM data
  33. GRB 010326B: Optical observations
  34. GRB010324, optical observations
  35. GRB010326B: Localization by HETE (2nd GRB for this date)
  36. GRB 010326: Optical observations
  37. GRB 010326 optical observations
  38. GRB010326: Refined Localization by HETE
  39. GRB010326: Localization by HETE
  40. Duration, ECT, peak flux and fluence of GRB010324
  41. Optical Observations of GRB 010324
  42. IPN TRIANGULATION OF GRB010324
  43. GRB010222, late-time optical observation
  44. Support extension to the BeppoSAX mission
  45. GRB 010222 - HEGRA GeV/TeV Observations
  46. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  47. GRB010222: Chandra X-ray Observatory Observation
  48. GRB010222: Sub-millimeter vanishing act
  49. GRB010222 - Optical observation
  50. GRB 010222, Optical Observations
  51. GRB010220 optical obsercations
  52. GRB010222 - Optical observation
  53. GRB 010222: High-Resolution Keck Spectroscopy
  54. GRB010222: Optical observation and decay
  55. GRB 010214, I-band data
  56. Sub-millimeter Excess/GRB 010222
  57. GRB 010222
  58. GRB 010222 HST/Chandra TOO
  59. GRB 010222
  60. GRB010222 further R-band photometry
  61. GRB010222: R-band data
  62. GRB010222 Optical observations
  63. GRB 010222: Keck Spectroscopy
  64. GRB010214, field photometry
  65. GRB010222, field photometry
  66. GRB010222 further R-band photometry
  67. GRB010222, possible increase of optical decay slope
  68. GRB 010222 Kyoto optical observation
  69. GRB010222: fading behavior
  70. GRB 010222 BV optical observations
  71. GRB010220, Optical Observations
  72. GRB010222 R-BAND OBSERVATION
  73. GRB 010220: Near-IR Observations
  74. GRB010214 follow-up from Hanle
  75. GRB 010222: Near-IR Observations
  76. GRB 010222: Optical Observations
  77. GRB 010222, Decay Slope Confirmed
  78. GRB010222: Another absorption line system
  79. GRB010222: Optical decay slope
  80. GRB010222: Sub-millimeter detection
  81. GRB010222: R-band fading behavior
  82. GRB010222: Optical Observations
  83. GRB010222, radio observations
  84. GRB010222, optical observations
  85. GRB010222: BeppoSAX/NFI Observations
  86. Redshift of the Optical Transient of GRB010222
  87. GRB010214B,Gamma Ray Observations
  88. GRB010222: possible optical counterpart
  89. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  90. GRB010220, Radio and Optical Observations
  91. GRB 010220, simultaneous optical observations
  92. GRB010220: BeppoSAX WFC and GRBM preliminary data
  93. GRB010214, candidate optical afterglow
  94. GRB010214, optical observations
  95. BeppoSAX ALERT: GRB010220
  96. GRB010214: BeppoSAX WFC and GRBM preliminary data
  97. GRB 010214: X-Ray afterglow
  98. GRB 010214, Optical Observations
  99. GRB 010214 optical observation
  100. GRB010213, Radio Observations

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