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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"

44387 results found.

  1. GRB010222 - Optical observation
  2. GRB 010222: High-Resolution Keck Spectroscopy
  3. GRB010222: Optical observation and decay
  4. GRB 010214, I-band data
  5. Sub-millimeter Excess/GRB 010222
  6. GRB 010222
  7. GRB 010222 HST/Chandra TOO
  8. GRB 010222
  9. GRB010222 further R-band photometry
  10. GRB010222: R-band data
  11. GRB010222 Optical observations
  12. GRB 010222: Keck Spectroscopy
  13. GRB010214, field photometry
  14. GRB010222, field photometry
  15. GRB010222 further R-band photometry
  16. GRB010222, possible increase of optical decay slope
  17. GRB 010222 Kyoto optical observation
  18. GRB010222: fading behavior
  19. GRB 010222 BV optical observations
  20. GRB010220, Optical Observations
  21. GRB010222 R-BAND OBSERVATION
  22. GRB 010220: Near-IR Observations
  23. GRB010214 follow-up from Hanle
  24. GRB 010222: Near-IR Observations
  25. GRB 010222: Optical Observations
  26. GRB 010222, Decay Slope Confirmed
  27. GRB010222: Another absorption line system
  28. GRB010222: Optical decay slope
  29. GRB 010214, Optical Observations
  30. GRB010222: Sub-millimeter detection
  31. GRB010222: R-band fading behavior
  32. GRB010222: Optical Observations
  33. GRB010222, radio observations
  34. GRB010222, optical observations
  35. GRB010222: BeppoSAX/NFI Observations
  36. Redshift of the Optical Transient of GRB010222
  37. GRB010214B,Gamma Ray Observations
  38. GRB010222: possible optical counterpart
  39. GRB010222
  40. GRB010222: BeppoSAX refined position
  41. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  42. GRB010220, Radio and Optical Observations
  43. GRB 010220, simultaneous optical observations
  44. GRB010220: BeppoSAX WFC and GRBM preliminary data
  45. GRB010214, candidate optical afterglow
  46. GRB010214, optical observations
  47. BeppoSAX GRB010220: refined position
  48. BeppoSAX ALERT: GRB010220
  49. GRB010214: BeppoSAX WFC and GRBM preliminary data
  50. GRB 010214: X-Ray afterglow
  51. GRB 010214, Optical Observations
  52. GRB 010214 optical observation
  53. GRB010213, Radio Observations
  54. GRB010213 Optical Observation
  55. GRB010213, Radio Observations
  56. J-Band Observation of GRB 010214.
  57. GRB010214, Radio Observations
  58. GRB010214, optical observations
  59. GRB010213, optical observations
  60. GRB010213, Near-IR observations
  61. Possible InfraRed Transient of GRB 010214.
  62. GRB010214 Optical Observation
  63. GRB010214: BeppoSAX/NFI Observations
  64. GRB010213 (HETE) TAROT observations
  65. GRB 010214, optical observations
  66. GRB010213 detected by HETE
  67. GRB010214 refined WFC position
  68. BeppoSAX ALERT: GRB010214
  69. IPN Status Report
  70. HETE Status
  71. GRB010126 opt. obs.
  72. IPN/RXTE TRIANGULATION OF GRB010126
  73. GRB010126: CONCAM crude optical limits during GRB
  74. GRB010126, TNG R-band observations
  75. GRB010126 Optical Observations
  76. GRB010126 optical observations
  77. GRB010126: Optical observations
  78. IPN TRIANGULATION OF GRB010126
  79. IPN/RXTE TRIANGULATION OF GRB010126
  80. GRB 010119, optical observations
  81. GRB010119: Optical observations
  82. Optical Observations of GRB 001018 at Keck
  83. GRB010119, Radio observations
  84. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  85. Optical observations of GRB 001018 with JCAM
  86. IPN TRIANGULATION OF GRB010115
  87. IPN TRIANGULATION OF GRB010109
  88. IPN TRIANGULATION OF GRB010109
  89. GRB010103, optical observations
  90. IPN triangulation of GRB010104
  91. IPN triangulation of GRB010103
  92. GRB 001204: Ks observations
  93. H band observation of GRB 001212
  94. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  95. IPN triangulation of GRB001219
  96. GRB 001212 Optical Observation
  97. GRB 001212 Optical Observation
  98. GRB 001212 optical observation
  99. GRB 001212 possible OA in 2MASS
  100. GRB 001212 possible OA

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