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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"

25833 results found.

  1. GRB 081003B: a long GRB detected with INTEGRAL
  2. GRB 080928: Fermi GBM detection
  3. GRB 081003: A long GRB discovered by INTEGRAL
  4. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  5. Trigger 330353: Swift detection of a Galactic short soft burst
  6. GRB 081001: Observations from OSN
  7. GRB 080925: Suzaku WAM observation of the prompt emission
  8. GRB 081001: Swift UVOT Observations
  9. GRB 081001: Swift-XRT position
  10. GRB081001: SuperAGILE Localization of a long GRB
  11. GRB 080928: Watcher observations
  12. GRB 080927: Fermi GBM detection
  13. GRB 080928: VLT redshift
  14. GRB 080928: Swift-XRT refined analysis
  15. GRB 080928, Swift-BAT final refined analysis
  16. GRB 080928: GROND DETECTION
  17. GRB 080928: Enhanced Swift-XRT position
  18. GRB 080928, Swift-BAT initial refined analysis
  19. GRB 080928A: ROTSE-III Confirmation of Optical Counterpart
  20. GRB 080928: Swift detection of a burst with an optical counterpart
  21. GRB 080925: Fermi GBM Detection
  22. GRB 080920: Fermi GBM detection
  23. GRB080922, optical upper limit
  24. Swift trigger 325707: Swift/UVOT Upper Limits
  25. Swift trigger 325707: Swift-XRT upper limit
  26. Swift detection of a possible GRB (trigger 325707)
  27. GRB080916A: Suzaku WAM observation of the prompt emission
  28. GRB 080922: Swift/UVOT Upper Limits
  29. GRB080922: Swift-XRT upper limit
  30. GRB080922: A long GRB detected by INTEGRAL
  31. GRB 080913B: Fermi GBM detection
  32. Trigger 324561: IGR J08408-4503 detected by Swift
  33. GRB 080919: Swift-XRT refined analysis
  34. GRB 080919, Swift-BAT refined analysis
  35. GRB 080916C: IRSF/SIRUS NIR Observation
  36. GRB 080916C: GROND Confirmation of the Optical Afterglow
  37. GRB 080916C: GROND Confirmation of the Optical Afterglow
  38. GRB 080919: REM NIR observations
  39. GRB 080919: Swift detection of a short burst
  40. GRB 080915A: GROND upper limits
  41. GRB 080916A: GROND lightcurve
  42. SGR 0501+4516: preliminary results of the Suzaku ToO observation
  43. GRB 080916A: Fermi GBM detection
  44. GRB 080916C: Swift UVOT Refined Analysis
  45. GRB 080916C: Swift XRT refined analysis
  46. GRB 080916B: Swift-XRT refined analysis
  47. Konus-Wind observation of GRB 080916A
  48. GRB 080916C: GROND Detection of the Optical Afterglow Candidate
  49. GRB 080913: Konus-Wind and Swift/BAT joint spectral analysis
  50. GRB 080916C: Enhanced XRT position
  51. GRB080916A: Spectroscopic redshift
  52. GRB 080916C: Swift/XRT detection of possible afterglow
  53. GRB 080916B: Swift UVOT Refined Analysis
  54. GRB 080916B, Swift-BAT refined analysis
  55. GRB080916A: Refined Swift/UVOT Observations
  56. GRB 080915a, SMARTS optical/IR observations
  57. GRB 080916B: Enhanced Swift-XRT position
  58. GRB 080916C: Fermi LAT observation
  59. GRB 080916C: Fermi GBM Detection
  60. GRB 080916A: Swift XRT refined analysis
  61. GRB 080916A, Swift-BAT refined analysis
  62. GRB 080916B: Swift-XRT afterglow detection
  63. GRB 080916A: Enhanced Swift-XRT position
  64. GRB 080916: REM detection of the NIR afterglow
  65. GRB 080916: REM candidate afterglow
  66. GRB 080916: Swift detection of a burst with optical afterglow
  67. GRB 080915B, Swift-BAT refined analysis
  68. GRB 080912 : Fermi GBM detection
  69. GRB 080915: REM NIR early observations
  70. GRB 080915: Swift/UVOT Upper Limits
  71. GRB 080915: Swift-XRT afterglow detection and analysis
  72. GRB 080915, Swift-BAT refined analysis
  73. GRB 080915: ROTSE-III Optical Limits
  74. GRB 080913: Swift-XRT refined analysis
  75. GRB080913: Swift/UVOT Upper Limits
  76. GRB 080913, Swift-BAT refined analysis
  77. GRB 080913: VLT/FORS2 observations
  78. GRB 080913: REM NIR early observations
  79. GRB 080913: Enhanced Swift-XRT position
  80. GRB 080913: GROND observation of a high-z optical/NIR afterglow candidate
  81. GRB 080913: Swift detection of a burst
  82. GRB 080906: Watcher observations
  83. Swift-BAT/-XRT refined analysis on trigger 324362 (LS I +61 303)
  84. GRB 080906B: Fermi GBM detection
  85. GRB 080905C: Fermi GBM detection
  86. SGR J0501+4516: radio pulsar searches with GBT and WSRT
  87. Swift trigger 324362 (LS I +61 303 ?)
  88. GRB080905A: Swift/UVOT Upper Limits
  89. GRB 080905B: Watcher optical detection
  90. GRB 080904: Fermi Gamma-ray Burst Monitor detection
  91. GRB 080905B: Fermi Gamma-ray Burst Monitor detection
  92. GRB 080905A: Fermi Gamma-ray Burst Monitor detection
  93. GRB 080905A: MITSuME Akeno optical upper limits
  94. GRB 080906: Refined Swift/UVOT Observations
  95. GRB 080906: Swift-XRT Refined Analysis
  96. GRB 080906, Swift-BAT refined analysis
  97. GRB 080905A: optical afterglow
  98. GRB 080906: GROND observations of the optical/NIR afterglow
  99. GRB 080905B: Refined UVOT Analysis
  100. GRB 080905B: VLT redshift

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