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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"

19221 results found.

  1. GRB 070520B: Swift/UVOT Upper Limits
  2. GRB 070520A: Subaru Observations
  3. GRB 070520A: Swift UVOT Upper Limits
  4. GRB 070521: TAROT La Silla observatory optical observations
  5. GRB070521 - SDSS Pre-Burst Observations
  6. GRB 070521: Swift detection of a burst
  7. GRB 070520A: MITSuME Akeno optical upper limits
  8. GRB 070518: TNG observations
  9. GRB 070520B: Swift detection of a burst
  10. GRB 070520: Xinglong EST optical Upper Limit
  11. GRB 070520: Swift detection of a burst
  12. VLA observation of GRB 070518
  13. GRB070518: UVOT refined analysis
  14. GRB 070518, Swift-BAT refined analysis
  15. GRB 070518: OT confirmed form Xinglong TNT observation
  16. GRB 070518: Swift detection of a burst with optical afterglow
  17. GRB 070517: Optical search
  18. GRB 070517: Swift detection of a burst
  19. GRB 070509: objects inside XRT error circle
  20. GRB 070512: IPN localization and Konus spectrum of a bright burst
  21. GRB 070509: Swift/UVOT Upper Limits
  22. Konus-Wind and Konus-A observation of GRB 070508
  23. RHESSI Spectrum of GRB070508
  24. GRB 070508: Suzaku/WAM observation of the prompt emission
  25. GRB 070509: REM observations
  26. GRB 070509: ROTSE-III Optical Limits
  27. GRB070508: Swift/UVOT Observations
  28. GRB 070508, Swift-BAT refined analysis
  29. GRB 070508: REM observations
  30. GRB 070508: TAROT La Silla observatory optical observations
  31. GRB 070508: Swift detection of an intense burst with an optical counterpart
  32. GRB070506: Swift/UVOT Observations
  33. GRB 070506: Swift detection of a burst with optical afterglow
  34. GRB070429B: VLT observations
  35. GRB070429B: position correction
  36. GRB 070309: Swift-XRT afterglow confirmation
  37. VLA observation of GRB 070429B
  38. Swift/UVOT observations of GRB070429B
  39. Swift/UVOT observations of GRB070429A
  40. GRB 070429A: optical and NIR observations
  41. GRB 070429B: ROTSE-III Optical Limits
  42. GRB 070429: ROTSE-III Optical Limits
  43. GRB 070429: Swift detection of a burst
  44. LT monitoring of GRB070412
  45. GRB 070427: Swift detection of a burst
  46. GRB 070411: Late-time Keck imaging
  47. GRB070419B: Suzaku WAM observation of the prompt emission
  48. Konus-Wind observation of GRB 070420
  49. GRB 070420 Swift-BAT Refined Analysis
  50. GRB070420: Swift UVOT continuing observations
  51. GRB 070420: Faulkes Telescope South Observations
  52. GBR 070419A: Swift/XRT refined analysis
  53. GRB 070420: TAROT La Silla observatory optical observations
  54. GRB 070420: NIR and optical afterglow confirmed
  55. GRB 070420: Swift detection of a burst with optical afterglow
  56. GRB 070419A: MITSuME Okayama Observations
  57. GRB 070419A: Early Super-LOTIS Observations
  58. GRB070419 - SDSS Pre-Burst Observations
  59. GRB 070419A: SARA observations
  60. GRB 070419A: NAYUTA Optical Observation
  61. GRB 070419A: Optical and IR observations with KANATA
  62. GRB070419A, optical observation
  63. Infrared detection of GRB070419A with UKIRT
  64. GRB 070419A: Kiso Optical observation
  65. GRB 070419: P60 Confirmation of Optical Afterglow
  66. GRB 070419B: Swift detection of a burst
  67. GRB 070419A: ROTSE-III Optical Limits
  68. GRB 070419: Swift detection of a burst
  69. GRB 070418: Optical and IR observations with KANATA
  70. Trigger 276045: Swift detection of a possible burst
  71. GRB 070406: Swift XRT refined analysis
  72. GRB070412: UKIRT-WFCAM JHK upper limits
  73. GRB070412: Swift UVOT observations
  74. GRB 070411: Swift/UVOT observations
  75. GRB 070412, Swift-BAT refined analysis
  76. GRB 070412 Liverpool Telescope optical limit
  77. GRB 070412: Optical observations at Crni Vrh
  78. GRB 070412: further NOT observations
  79. GRB 070412: IAC80 optical afterglow candidate
  80. GRB 070412: NOT observations
  81. GRB 070411, Swift-BAT refined analysis
  82. GRB 070412: Swift detection of a burst
  83. GRB 070411: IAC80 optical observations
  84. GRB 070411 : Liverpool Telescope Observations
  85. GRB 070411: Tautenburg RRM Afterglow Confirmation
  86. GRB 070411: Swift detection of a burst with optical afterglow
  87. GRB 070406: Swift XRT team further analysis
  88. Suzaku ToO observation of SGR 1806-20
  89. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  90. GRB 070406: Correction to the optical candidate in GCN6253
  91. GRB 070406: Gemini South Imaging and XRT analysis
  92. GRB070406: Swift UVOT observations
  93. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  94. GRB 070406: NOT observations
  95. GRB 070406: SARA upper limit
  96. GRB 070406: Xinglong TNT optical Upper Limit
  97. GRB 070402: Suzaku WAM observation of the prompt emission
  98. Konus-Wind and Konus-A observations of GRB 070402
  99. IPN triangulation of GRB070402
  100. GRB 070328: Suzaku WAM observation of the prompt emission

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