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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').
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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"

32815 results found.

  1. GRB010324, field photometry
  2. GRB010326B, field photometry
  3. GRB010326, field photometry
  4. GRB010220, field photometry
  5. Further Optical Observations of GRB 010324
  6. GRB 010326A: Further optical observations
  7. GRB010324: BeppoSAX/GRBM data
  8. GRB 010326B: Optical observations
  9. GRB010324, optical observations
  10. GRB010326B: Localization by HETE (2nd GRB for this date)
  11. GRB 010326: Optical observations
  12. GRB 010326 optical observations
  13. GRB010326: Refined Localization by HETE
  14. GRB010326: Localization by HETE
  15. Duration, ECT, peak flux and fluence of GRB010324
  16. Optical Observations of GRB 010324
  17. IPN TRIANGULATION OF GRB010324
  18. GRB990705, VLT-FORS1 observations of the host galaxy
  19. GRB010222, late-time optical observation
  20. Support extension to the BeppoSAX mission
  21. GRB 010222 - HEGRA GeV/TeV Observations
  22. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  23. GRB010222: Chandra X-ray Observatory Observation
  24. GRB010222: Sub-millimeter vanishing act
  25. GRB 010222, Optical Observations
  26. GRB 010222: High-Resolution Keck Spectroscopy
  27. GRB 010214, I-band data
  28. Sub-millimeter Excess/GRB 010222
  29. GRB 010222
  30. GRB 010222 HST/Chandra TOO
  31. GRB 010222
  32. GRB010222 further R-band photometry
  33. GRB010222: R-band data
  34. GRB010222 Optical observations
  35. GRB 010222: Keck Spectroscopy
  36. GRB010214, field photometry
  37. GRB010222, field photometry
  38. GRB010222 further R-band photometry
  39. GRB010222, possible increase of optical decay slope
  40. GRB 010222 Kyoto optical observation
  41. GRB010222: fading behavior
  42. GRB 010222 BV optical observations
  43. GRB 010220: Near-IR Observations
  44. GRB010214 follow-up from Hanle
  45. GRB 010222: Near-IR Observations
  46. GRB 010222: Optical Observations
  47. GRB 010222, Decay Slope Confirmed
  48. GRB010222: Another absorption line system
  49. GRB010222: Optical decay slope
  50. GRB 010214, Optical Observations
  51. GRB010222: Sub-millimeter detection
  52. GRB010222: R-band fading behavior
  53. GRB010222: Optical Observations
  54. GRB010222, optical observations
  55. GRB010222: BeppoSAX/NFI Observations
  56. Redshift of the Optical Transient of GRB010222
  57. GRB010214B,Gamma Ray Observations
  58. GRB010222
  59. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  60. GRB 010220, simultaneous optical observations
  61. GRB010220: BeppoSAX WFC and GRBM preliminary data
  62. BeppoSAX ALERT: GRB010220
  63. GRB010214: BeppoSAX WFC and GRBM preliminary data
  64. GRB 010214: X-Ray afterglow
  65. GRB 010214, Optical Observations
  66. GRB 010214 optical observation
  67. GRB010213 Optical Observation
  68. J-Band Observation of GRB 010214.
  69. GRB010213, Near-IR observations
  70. Possible InfraRed Transient of GRB 010214.
  71. GRB010214 Optical Observation
  72. GRB010214: BeppoSAX/NFI Observations
  73. GRB010213 (HETE) TAROT observations
  74. GRB 010214, optical observations
  75. BeppoSAX ALERT: GRB010214
  76. IPN Status Report
  77. HETE Status
  78. GRB010126 opt. obs.
  79. IPN/RXTE TRIANGULATION OF GRB010126
  80. GRB010126: CONCAM crude optical limits during GRB
  81. GRB010126, TNG R-band observations
  82. IPN TRIANGULATION OF GRB010126
  83. IPN/RXTE TRIANGULATION OF GRB010126
  84. GRB 010119, optical observations
  85. GRB010119: Optical observations
  86. Optical Observations of GRB 001018 at Keck
  87. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  88. Optical observations of GRB 001018 with JCAM
  89. IPN TRIANGULATION OF GRB010115
  90. IPN TRIANGULATION OF GRB010109
  91. GRB010103, optical observations
  92. IPN triangulation of GRB010104
  93. IPN triangulation of GRB010103
  94. GRB 001204: Ks observations
  95. H band observation of GRB 001212
  96. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  97. IPN triangulation of GRB001219
  98. GRB 001212 Optical Observation
  99. GRB 001212 Optical Observation
  100. GRB 001212 optical observation

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