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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"

20383 results found.

  1. Giant flare from SGR1900+14
  2. GRB 010326b Optical Observations
  3. GRB010412: BeppoSAX GRBM and WFC observations
  4. GRB010324, revised field photometry
  5. GRB 980326: Late-time HST/STIS observations
  6. GRB010324, field photometry
  7. GRB010326B, field photometry
  8. GRB010326, field photometry
  9. GRB010220, field photometry
  10. Further Optical Observations of GRB 010324
  11. GRB010222, CXO X-ray observations
  12. GRB010324, optical observations
  13. GRB010326B: Localization by HETE (2nd GRB for this date)
  14. GRB 010326 optical observations
  15. GRB010326: Refined Localization by HETE
  16. GRB010326: Localization by HETE
  17. Optical Observations of GRB 010324
  18. GRB010222, late-time optical observation
  19. Support extension to the BeppoSAX mission
  20. GRB 010222 - HEGRA GeV/TeV Observations
  21. GRB010222 - Optical observation
  22. GRB 010222, Optical Observations
  23. GRB 010214, I-band data
  24. GRB010222 further R-band photometry
  25. GRB 010222: Keck Spectroscopy
  26. GRB010214, field photometry
  27. GRB010222, field photometry
  28. GRB010222 further R-band photometry
  29. GRB010222, possible increase of optical decay slope
  30. GRB 010222 Kyoto optical observation
  31. GRB 010222 BV optical observations
  32. GRB010222 R-BAND OBSERVATION
  33. GRB010214 follow-up from Hanle
  34. GRB 010222: Near-IR Observations
  35. GRB 010222: Optical Observations
  36. GRB010222, radio observations
  37. GRB010222, optical observations
  38. GRB010220, Radio and Optical Observations
  39. GRB 010220, simultaneous optical observations
  40. GRB010220: BeppoSAX WFC and GRBM preliminary data
  41. GRB010214, optical observations
  42. BeppoSAX GRB010220: refined position
  43. GRB010214: BeppoSAX WFC and GRBM preliminary data
  44. GRB 010214: X-Ray afterglow
  45. GRB 010214 optical observation
  46. J-Band Observation of GRB 010214.
  47. GRB010213, Near-IR observations
  48. Possible InfraRed Transient of GRB 010214.
  49. GRB010213 (HETE) TAROT observations
  50. GRB010213 detected by HETE
  51. IPN Status Report
  52. HETE Status
  53. GRB010126 Optical Observations
  54. IPN TRIANGULATION OF GRB010126
  55. Optical Observations of GRB 001018 at Keck
  56. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  57. Optical observations of GRB 001018 with JCAM
  58. IPN TRIANGULATION OF GRB010115
  59. IPN TRIANGULATION OF GRB010109
  60. IPN TRIANGULATION OF GRB010109
  61. IPN triangulation of GRB010104
  62. IPN triangulation of GRB010103
  63. IPN triangulation of GRB001219
  64. GRB 001212 Optical Observation
  65. GRB 001212 Optical Observation
  66. GRB 001212 possible OA
  67. IPN triangulation of GRB001212
  68. Confirmation of IPN position for GRB001204
  69. IPN triangulation of GRB001204 (short/hard)
  70. GRB001120, optical observations
  71. WSRT 4.8 GHz observations of GRB001109
  72. IPN triangulation of GRB001120
  73. GRB 001109: deep JHK upper limits
  74. GRB 001109 X-ray afterglow with BeppoSAX
  75. CORRECTION to XMM-Newton observation of GRB001025
  76. GRB001109, Radio observations
  77. BeppoSAX ALERT: GRB001109
  78. GRB001105 BVRI field photometry correction
  79. GRB001105, BVRI field photometry
  80. IPN TRIANGULATION OF GRB001105
  81. GRB 001025B, Optical obervations
  82. GRB 991208: HST Imaging of the Host Galaxy
  83. GRB 001025B, I-band observations
  84. XMM-Newton observation of GRB001025
  85. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  86. GRB001007: Optical observations
  87. ASM Localization of GRB 001025
  88. GRB001007, Radio observations
  89. IPN TRIANGULATION OF GRB001019
  90. IPN TRIANGULATION OF GRB001018
  91. IPN TRIANGULATION OF GRB 001017
  92. V,R,I band observations of GRB000926
  93. HETE positions added to GCN
  94. GRB 001007, BVR-band observations
  95. GRB000926 - Amateur Optical Observations
  96. CONCAM null result on GRB001005
  97. IPN triangulation of GRB001007
  98. GRB000926 - Optical observations
  99. GRB000926 - Optical observations
  100. GRB 000926, Optical Observations

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