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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

28096 results found.

  1. GRB 101017A: Swift XRT refined analysis
  2. GRB 101017A: Swift/UVOT Observations
  3. GRB 101008A: optical observations
  4. GRB101017A: MITSuME Okayama optical upper limits
  5. GRB 101017A: Enhanced Swift-XRT position
  6. GRB 101017A: Swift-BAT refined analysis
  7. GRB 101017A: Swift detection of a burst with optical counterpart
  8. GRB 101014A: Fermi GBM detection
  9. GRB 100906A: D50 optical detection
  10. GRB 100902A: D50 optical limit
  11. GRB 101011A: Swift/UVOT observations
  12. GRB 101011A, GROND upper limits
  13. GRB 101011A: Zadko observatory - Gingin optical observations
  14. GRB 101011A: XRT Refined Analysis
  15. GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
  16. GRB 101011A: Enhanced Swift-XRT position
  17. GRB 101011A: Swift-BAT refined analysis
  18. GRB 101011A: Swift detection of a burst
  19. GRB 101008A: Swift-BAT refined analysis
  20. GRB101008A, GROND detection of a fading afterglow
  21. GRB 101008A: Swift-XRT refined analysis
  22. GRB 101008A: SAO RAS optical observations
  23. GRB 100915 optical upper limit
  24. GRB 101008: Swift/UVOT Upper Limits
  25. GRB 101008A: Enhanced Swift-XRT position
  26. GRB 101008A: Swift/XRT Detection of an Afterglow with no UVOT Counterpart
  27. GRB 101008A: Swift detection of a burst
  28. Refined analysis shows Swift Trigger 435520 is not a GRB
  29. Swift Trigger 435520 is probably not a GRB
  30. GRB 100925A / MAXI J1659-152: MASTER optical observations
  31. GRB 100924A: Suzaku WAM observation of the prompt emission
  32. GRB 100928A, Swift-BAT refined analysis
  33. GRB 100924A: Fermi GBM observation
  34. GRB 100928A: Swift detection of a burst
  35. GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
  36. GRB 100925A / MAXI J1659-152: SARA-S Observations
  37. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  38. GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
  39. GRB 100925A/MAXI J1659-152 - NOT optical observations
  40. GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations
  41. GRB 100925A: Nearby DSS Source - SN-GRB or new Galactic transient?
  42. GRB100925A UVOT afterglow
  43. GRB 100924A: GROND detection of an optical/NIR afterglow
  44. GRB 100925A: Swift detection of a burst
  45. GRB 100924A: Swift-BAT refined analysis
  46. GRB 100917A: TAROT La Silla observatory optical observations
  47. GRB 100915A: TAROT Calern observatory optical observations
  48. GRB100906A: Ashra-1 observation of early optical emission
  49. GRB 100916A: Fermi GBM detection
  50. GRB 100917A: Swift-BAT refined analysis
  51. GRB 100917A: Swift detection of a burst
  52. GRB100915A: MITSuME Ishigakijima Optical upper limits
  53. GRB 100915B: GRT Optical Observation
  54. GRB 100915A: GRT Optical Observation
  55. GRB 100915B: Fermi GBM observation
  56. GRB 100915A: Correction to Swift-BAT refined analysis
  57. GRB 100915A: Swift/UVOT Upper Limits
  58. GRB 100915A: Swift-BAT refined analysis
  59. GRB 100915A: Swift-XRT refined analysis
  60. GRB 100915A: Enhanced Swift-XRT position
  61. GRB 100915B: a long GRB detected by INTEGRAL
  62. GRB 100915A: Swift detection of a likely burst
  63. GRB 100910A: Fermi GBM detection
  64. Swift BAT Trigger 433953 probably not a GRB
  65. GRB100909A: MITSuME Ishigakijima Optical upper limits
  66. GRB 100909A: Swift/UVOT observations
  67. GRB 100901A: errata of GRB name in GCN 11270
  68. GRB 100909A: Swift-XRT refined analysis
  69. GRB 100906A: optical observations at Mt.Terskol
  70. GRB 100901A: optical observation in Maidanak, break confirmation
  71. GRB 100909A: Faulkes Telescope North afterglow candidate
  72. GRB 100902A : Confirmation of afterglow and re-brightening with CFHT r’-band imaging
  73. GRB 100909A: Swift target of opportunity observation
  74. GRB100906A: detection at 15GHz
  75. GRB100901A: IAO optical upper limits at 4 days after the burst
  76. GRB100906A: R band observations
  77. GRB100906A: non-detection at 15GHz
  78. GRB100906A: Optical observations at IAO
  79. GRB 100906A: Fermi GBM observation
  80. GRB 100906A: Swift-XRT refined analysis
  81. GRB 100906A: Enhanced Swift-XRT position
  82. GRB 100906A: Swift/UVOT Observations
  83. GRB100906A: MITSuME Okayama Optical Observation
  84. GRB 100905A: Swift/UVOT Upper Limits
  85. GRB 100901A: TLS observations, SDSS calibration, decay slope
  86. GRB 100906A: MASTER preliminary prompt+afterglow lc
  87. GRB 100906A: Swift-BAT refined analysis
  88. GRB 100906A: Swift detection of a burst with an optical afterglow
  89. GRB 100829A: MASTER optical observations
  90. GRB100905A: Optical upper limits at IAO
  91. GRB100905A: MITSuME Okayama optical upper limits
  92. GRB 100905A: Swift-XRT refined analysis.
  93. GRB100905A: 1.5m OSN upper limit
  94. GRB 100905A: Enhanced Swift-XRT position
  95. GRB 100905A: Swift-BAT refined analysis
  96. GRB 100905A: Faulkes Telescope North observations
  97. GRB 100905A: Swift detection of a burst
  98. GRB10901A: Murikabushi telescope observation at 3 days after the burst
  99. GRB 100901A: Submm observations from SMA
  100. GRB 100904A: Swift-BAT refined analysis

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