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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3363 results found.

  1. GRB 090515: Lick Upper Limits
  2. GRB 090515: Swift-BAT refined spectral analysis
  3. Fermi Gamma-ray Burst Monitor trigger 263649437 is not a GRB
  4. GRB 090424: optical observations
  5. GRB 090418A BVRcIc field calibration
  6. GRB 090429B: Swift-BAT refined analysis
  7. GRB 090424: Continued R-band monitoring
  8. GRB 090425: Fermi GBM detection
  9. GRB 090426, RIMOTS optical upper limits
  10. GRB 090426: Swift detection of a burst with an optical counterpart
  11. GRB090424: BVRI/R-band detection after 15 hrs burst
  12. GRB 090424: Swift-BAT refined analysis
  13. GRB090418A Rc-band photometry
  14. GRB 090423: Swift-BAT refined analysis
  15. GRB 090423: Faulkes Telescope South observations
  16. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  17. GRB 090418A: optical observations
  18. GRB 090418A: Swift/UVOT Observations
  19. VLA radio detection of GRB 090418
  20. GRB 090418: Swift detection of a burst with optical afterglow
  21. GRB 090418 OA candidate
  22. GRB 090417B: Swift-BAT refined analysis
  23. GRB 090417A: Swift-BAT refined analysis
  24. GRB 090410: Suzaku WAM observation of the prompt emission
  25. GRB 090410: MITSuME optical upper limits
  26. GRB 090410: Swift detection of a burst
  27. GRB 090404: NOT observations
  28. GRB 090404: Swift detection of a burst
  29. GRB 090401B: Swift-BAT refined analysis
  30. GRB 090401B: Swift detection of a burst
  31. GRB 090320B: Fermi GBM detection.
  32. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  33. GRB 090308: Swift detection of a burst
  34. GRB 090306B: Burst detection from Swift-BAT slew data
  35. Konus-RF catches first GRB and SGR bursts
  36. GRB 090301A: Swift-BAT refined analysis
  37. IPN localization of GRB 090217
  38. SGR activity seen by BAT during ICSP Ionospheric Events
  39. GRB 090201: Swift-BAT refined analysis
  40. AXP 1E1547.0-5408: RHESSI observations up to 400 keV
  41. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  42. GRB 090112: Fermi GBM detection
  43. GRB 081224: Suzaku WAM observation of the prompt emission
  44. GRB 081226: GROND afterglow candidate
  45. GRB 081222, Swift-BAT refined analysis
  46. GRB 081221, Swift-BAT refined analysis
  47. IPN localization of short hard GRB 081216
  48. GRB 081203A: Optical observations of Xinglong TNT telescope
  49. GRB 081203A: Swift-BAT refined analysis
  50. GRB 081203: Swift detection of a burst with a bright optical counterpart
  51. GRB 081128: Swift-BAT refined analysis
  52. GRB081121: Refined Swift/UVOT observations
  53. GRB 081121: Swift-BAT refined analysis
  54. GRB081121: Swift/UVOT observations
  55. GRB 081121: ROTSE-III Detection of Optical Counterpart
  56. GRB081118 : optical upper limit
  57. GRB 081024C: Fermi Gamma-ray Burst Monitor detection
  58. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  59. GRB 081028, Swift-BAT refined analysis
  60. Swift detection of a possible burst (trigger 332287)
  61. Detection of flare star Algol in Swift-BAT slew data
  62. GRB 081008: Galaxy associated with z=1.967 absorber
  63. Swift-BAT triggered on the flare star Algol
  64. GRB 081008 optical upper limit
  65. GRB 081011: Swift/XRT detection
  66. GRB081008: Swift/UVOT observations
  67. GRB 081008: Swift detection of a burst with optical afterglow
  68. GRB 081008: ROTSE-III Detection of Optical Counterpart
  69. GRB 081007: Swift detection of a burst with optical afterglow
  70. Trigger 324561: IGR J08408-4503 detected by Swift
  71. GRB 080916A: GROND lightcurve
  72. GRB 080916C: GROND Detection of the Optical Afterglow Candidate
  73. GRB080916A: Refined Swift/UVOT Observations
  74. GRB 080916A, Swift-BAT refined analysis
  75. GRB 080916: REM detection of the NIR afterglow
  76. GRB 080916: REM candidate afterglow
  77. GRB 080916: Swift detection of a burst with optical afterglow
  78. GRB 080915B, Swift-BAT refined analysis
  79. GRB 080913, Swift-BAT refined analysis
  80. Swift-BAT/-XRT refined analysis on trigger 324362 (LS I +61 303)
  81. GRB 080905B: Watcher optical detection
  82. GRB 080905B: Swift detection of a burst with possible optical counterpart
  83. GRB 080903, Swift-BAT refined analysis
  84. GRB 080830: Fermi Gamma-ray Burst Monitor detection
  85. INTEGRAL ToO observation of SGR0501+4516
  86. SGR 0501+4516: Decline in Activity
  87. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  88. GRB 080825B - optical counterpart candidate
  89. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  90. GRB 080727C, Swift-BAT refined analysis
  91. GRB 080727B: Swift/UVOT Upper Limits
  92. GRB 080727B, Swift-BAT refined analysis
  93. GRB 080727: Swift detection of a burst
  94. GRB 080721: UVOT Follow-Up Observations
  95. GRB 080721 : Lulin Optical follow-ups
  96. GRB 080721: Swift detection of a burst with a bright optical counterpart.
  97. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  98. GRB 080613B - NOT optical and IR nondetections
  99. GRB 080605, Swift-BAT refined analysis
  100. GRB 080605, Swift-BAT refined analysis

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