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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"

37509 results found.

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