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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"

36681 results found.

  1. GRB 010222
  2. GRB010222 further R-band photometry
  3. GRB010222: R-band data
  4. GRB010222 Optical observations
  5. GRB 010222: Keck Spectroscopy
  6. GRB010214, field photometry
  7. GRB010222, field photometry
  8. GRB010222 further R-band photometry
  9. GRB010222, possible increase of optical decay slope
  10. GRB 010222 Kyoto optical observation
  11. GRB010222: fading behavior
  12. GRB 010222 BV optical observations
  13. GRB 010220: Near-IR Observations
  14. GRB010214 follow-up from Hanle
  15. GRB 010222: Near-IR Observations
  16. GRB 010222: Optical Observations
  17. GRB 010222, Decay Slope Confirmed
  18. GRB010222: Another absorption line system
  19. GRB010222: Optical decay slope
  20. GRB 010214, Optical Observations
  21. GRB010222: Sub-millimeter detection
  22. GRB010222: R-band fading behavior
  23. GRB010222: Optical Observations
  24. GRB010222, optical observations
  25. GRB010222: BeppoSAX/NFI Observations
  26. Redshift of the Optical Transient of GRB010222
  27. GRB010214B,Gamma Ray Observations
  28. GRB010222
  29. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  30. GRB 010220, simultaneous optical observations
  31. GRB010220: BeppoSAX WFC and GRBM preliminary data
  32. BeppoSAX ALERT: GRB010220
  33. GRB010214: BeppoSAX WFC and GRBM preliminary data
  34. GRB 010214: X-Ray afterglow
  35. GRB 010214, Optical Observations
  36. GRB 010214 optical observation
  37. GRB010213 Optical Observation
  38. J-Band Observation of GRB 010214.
  39. GRB010213, Near-IR observations
  40. Possible InfraRed Transient of GRB 010214.
  41. GRB010214 Optical Observation
  42. GRB010214: BeppoSAX/NFI Observations
  43. GRB010213 (HETE) TAROT observations
  44. GRB 010214, optical observations
  45. BeppoSAX ALERT: GRB010214
  46. IPN Status Report
  47. HETE Status
  48. GRB010126 opt. obs.
  49. IPN/RXTE TRIANGULATION OF GRB010126
  50. GRB010126: CONCAM crude optical limits during GRB
  51. GRB010126, TNG R-band observations
  52. IPN TRIANGULATION OF GRB010126
  53. IPN/RXTE TRIANGULATION OF GRB010126
  54. GRB 010119, optical observations
  55. GRB010119: Optical observations
  56. Optical Observations of GRB 001018 at Keck
  57. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  58. Optical observations of GRB 001018 with JCAM
  59. IPN TRIANGULATION OF GRB010115
  60. IPN TRIANGULATION OF GRB010109
  61. GRB010103, optical observations
  62. IPN triangulation of GRB010104
  63. IPN triangulation of GRB010103
  64. GRB 001204: Ks observations
  65. H band observation of GRB 001212
  66. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  67. IPN triangulation of GRB001219
  68. GRB 001212 Optical Observation
  69. GRB 001212 Optical Observation
  70. GRB 001212 optical observation
  71. GRB 001212 possible OA in 2MASS
  72. GRB 001212 possible OA
  73. IPN triangulation of GRB001212
  74. Confirmation of IPN position for GRB001204
  75. IPN triangulation of GRB001204 (short/hard)
  76. GRB 001105, further optical observations
  77. GRB001120: Gunn-i observations
  78. GRB001120: Optical observations
  79. GRB001109, optical observations
  80. GRB001120, optical observations
  81. IPN triangulation of GRB001120
  82. Optical/NIR observations of GRB001109
  83. GRB 001109: deep JHK upper limits
  84. GRB 001109 X-ray afterglow with BeppoSAX
  85. GRB001109: Optical observations
  86. GRB001109: BeppoSAX/NFI Observations
  87. GRB001109, R-band optical observations
  88. GRB001109, Radio observations
  89. BeppoSAX ALERT: GRB001109
  90. GRB001105 BVRI field photometry correction
  91. GRB001105, BVRI field photometry
  92. GRB 001105, R-band observation
  93. IPN TRIANGULATION OF GRB001105
  94. GRB 001025B, Optical obervations
  95. GRB 991208: HST Imaging of the Host Galaxy
  96. GRB000926: R-image of the host galaxy
  97. GRB 001025B, I-band observations
  98. GRB 001025 Optical Observations
  99. GRB 001025A, optical observation
  100. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)

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