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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"

35427 results found.

  1. IPN Triangulation of the Giant Flare from SGR1900+14
  2. GRB010412, field photometry
  3. GRB 010326b Optical Observations
  4. GRB010412: Optical observations
  5. GRB010412: Optical observations
  6. IPN Triangulation of GRB010412
  7. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  8. BeppoSAX GRB ALERT: GRB010412
  9. GRB Observation Report
  10. GRB010324, revised field photometry
  11. REVISED LOCATION OF GRB010326A
  12. GRB 980326: Late-time HST/STIS observations
  13. GRB010324, field photometry
  14. GRB010326B, field photometry
  15. GRB010326, field photometry
  16. GRB010220, field photometry
  17. Further Optical Observations of GRB 010324
  18. GRB 010326A: Further optical observations
  19. GRB010324: BeppoSAX/GRBM data
  20. GRB 010326B: Optical observations
  21. GRB010324, optical observations
  22. GRB010326B: Localization by HETE (2nd GRB for this date)
  23. GRB 010326: Optical observations
  24. GRB 010326 optical observations
  25. GRB010326: Refined Localization by HETE
  26. GRB010326: Localization by HETE
  27. Duration, ECT, peak flux and fluence of GRB010324
  28. Optical Observations of GRB 010324
  29. IPN TRIANGULATION OF GRB010324
  30. GRB990705, VLT-FORS1 observations of the host galaxy
  31. GRB010222, late-time optical observation
  32. Support extension to the BeppoSAX mission
  33. GRB 010222 - HEGRA GeV/TeV Observations
  34. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  35. GRB010222: Chandra X-ray Observatory Observation
  36. GRB010222: Sub-millimeter vanishing act
  37. GRB 010222, Optical Observations
  38. GRB 010222: High-Resolution Keck Spectroscopy
  39. GRB 010214, I-band data
  40. Sub-millimeter Excess/GRB 010222
  41. GRB 010222
  42. GRB 010222 HST/Chandra TOO
  43. GRB 010222
  44. GRB010222 further R-band photometry
  45. GRB010222: R-band data
  46. GRB010222 Optical observations
  47. GRB 010222: Keck Spectroscopy
  48. GRB010214, field photometry
  49. GRB010222, field photometry
  50. GRB010222 further R-band photometry
  51. GRB010222, possible increase of optical decay slope
  52. GRB 010222 Kyoto optical observation
  53. GRB010222: fading behavior
  54. GRB 010222 BV optical observations
  55. GRB 010220: Near-IR Observations
  56. GRB010214 follow-up from Hanle
  57. GRB 010222: Near-IR Observations
  58. GRB 010222: Optical Observations
  59. GRB 010222, Decay Slope Confirmed
  60. GRB010222: Another absorption line system
  61. GRB010222: Optical decay slope
  62. GRB 010214, Optical Observations
  63. GRB010222: Sub-millimeter detection
  64. GRB010222: R-band fading behavior
  65. GRB010222: Optical Observations
  66. GRB010222, optical observations
  67. GRB010222: BeppoSAX/NFI Observations
  68. Redshift of the Optical Transient of GRB010222
  69. GRB010214B,Gamma Ray Observations
  70. GRB010222
  71. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  72. GRB 010220, simultaneous optical observations
  73. GRB010220: BeppoSAX WFC and GRBM preliminary data
  74. BeppoSAX ALERT: GRB010220
  75. GRB010214: BeppoSAX WFC and GRBM preliminary data
  76. GRB 010214: X-Ray afterglow
  77. GRB 010214, Optical Observations
  78. GRB 010214 optical observation
  79. GRB010213 Optical Observation
  80. J-Band Observation of GRB 010214.
  81. GRB010213, Near-IR observations
  82. Possible InfraRed Transient of GRB 010214.
  83. GRB010214 Optical Observation
  84. GRB010214: BeppoSAX/NFI Observations
  85. GRB010213 (HETE) TAROT observations
  86. GRB 010214, optical observations
  87. BeppoSAX ALERT: GRB010214
  88. IPN Status Report
  89. HETE Status
  90. GRB010126 opt. obs.
  91. IPN/RXTE TRIANGULATION OF GRB010126
  92. GRB010126: CONCAM crude optical limits during GRB
  93. GRB010126, TNG R-band observations
  94. IPN TRIANGULATION OF GRB010126
  95. IPN/RXTE TRIANGULATION OF GRB010126
  96. GRB 010119, optical observations
  97. GRB010119: Optical observations
  98. Optical Observations of GRB 001018 at Keck
  99. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  100. Optical observations of GRB 001018 with JCAM

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