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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"

37512 results found.

  1. GRB 980326: Late-time HST/STIS observations
  2. GRB010324, field photometry
  3. GRB010326B, field photometry
  4. GRB010326, field photometry
  5. GRB010220, field photometry
  6. Further Optical Observations of GRB 010324
  7. GRB 010326A: Further optical observations
  8. GRB010324: BeppoSAX/GRBM data
  9. GRB 010326B: Optical observations
  10. GRB010324, optical observations
  11. GRB010326B: Localization by HETE (2nd GRB for this date)
  12. GRB 010326: Optical observations
  13. GRB 010326 optical observations
  14. GRB010326: Refined Localization by HETE
  15. GRB010326: Localization by HETE
  16. Duration, ECT, peak flux and fluence of GRB010324
  17. Optical Observations of GRB 010324
  18. IPN TRIANGULATION OF GRB010324
  19. GRB990705, VLT-FORS1 observations of the host galaxy
  20. GRB010222, late-time optical observation
  21. Support extension to the BeppoSAX mission
  22. GRB 010222 - HEGRA GeV/TeV Observations
  23. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  24. GRB010222: Chandra X-ray Observatory Observation
  25. GRB010222: Sub-millimeter vanishing act
  26. GRB 010222, Optical Observations
  27. GRB 010222: High-Resolution Keck Spectroscopy
  28. GRB 010214, I-band data
  29. Sub-millimeter Excess/GRB 010222
  30. GRB 010222
  31. GRB 010222 HST/Chandra TOO
  32. GRB 010222
  33. GRB010222 further R-band photometry
  34. GRB010222: R-band data
  35. GRB010222 Optical observations
  36. GRB 010222: Keck Spectroscopy
  37. GRB010214, field photometry
  38. GRB010222, field photometry
  39. GRB010222 further R-band photometry
  40. GRB010222, possible increase of optical decay slope
  41. GRB 010222 Kyoto optical observation
  42. GRB010222: fading behavior
  43. GRB 010222 BV optical observations
  44. GRB 010220: Near-IR Observations
  45. GRB010214 follow-up from Hanle
  46. GRB 010222: Near-IR Observations
  47. GRB 010222: Optical Observations
  48. GRB 010222, Decay Slope Confirmed
  49. GRB010222: Another absorption line system
  50. GRB010222: Optical decay slope
  51. GRB 010214, Optical Observations
  52. GRB010222: Sub-millimeter detection
  53. GRB010222: R-band fading behavior
  54. GRB010222: Optical Observations
  55. GRB010222, optical observations
  56. GRB010222: BeppoSAX/NFI Observations
  57. Redshift of the Optical Transient of GRB010222
  58. GRB010214B,Gamma Ray Observations
  59. GRB010222
  60. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  61. GRB 010220, simultaneous optical observations
  62. GRB010220: BeppoSAX WFC and GRBM preliminary data
  63. BeppoSAX ALERT: GRB010220
  64. GRB010214: BeppoSAX WFC and GRBM preliminary data
  65. GRB 010214: X-Ray afterglow
  66. GRB 010214, Optical Observations
  67. GRB 010214 optical observation
  68. GRB010213 Optical Observation
  69. J-Band Observation of GRB 010214.
  70. GRB010213, Near-IR observations
  71. Possible InfraRed Transient of GRB 010214.
  72. GRB010214 Optical Observation
  73. GRB010214: BeppoSAX/NFI Observations
  74. GRB010213 (HETE) TAROT observations
  75. GRB 010214, optical observations
  76. BeppoSAX ALERT: GRB010214
  77. IPN Status Report
  78. HETE Status
  79. GRB010126 opt. obs.
  80. IPN/RXTE TRIANGULATION OF GRB010126
  81. GRB010126: CONCAM crude optical limits during GRB
  82. GRB010126, TNG R-band observations
  83. IPN TRIANGULATION OF GRB010126
  84. IPN/RXTE TRIANGULATION OF GRB010126
  85. GRB 010119, optical observations
  86. GRB010119: Optical observations
  87. Optical Observations of GRB 001018 at Keck
  88. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  89. Optical observations of GRB 001018 with JCAM
  90. IPN TRIANGULATION OF GRB010115
  91. IPN TRIANGULATION OF GRB010109
  92. GRB010103, optical observations
  93. IPN triangulation of GRB010104
  94. IPN triangulation of GRB010103
  95. GRB 001204: Ks observations
  96. H band observation of GRB 001212
  97. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  98. IPN triangulation of GRB001219
  99. GRB 001212 Optical Observation
  100. GRB 001212 Optical Observation

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