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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"

25046 results found.

  1. Swift/UVOT observations of GRB070429B
  2. GRB 070429B, Swift-BAT refined analysis
  3. Swift/UVOT observations of GRB070429A
  4. GRB 070429A, Swift-BAT refined analysis
  5. GRB 070429A: optical and NIR observations
  6. GRB 070429B: Swift XRT refined analysis
  7. GRB 070429B: ROTSE-III Optical Limits
  8. GRB 070429: ROTSE-III Optical Limits
  9. GRB 070429: Swift detection of a burst
  10. GRB 070427, Swift-BAT Refined Analysis
  11. LT monitoring of GRB070412
  12. GRB 070411: Late-time Keck imaging
  13. GRB070419B: Suzaku WAM observation of the prompt emission
  14. GRB 070420, SMARTS optical/IR afterglow observations
  15. GRB 070411, deep LBT photometry
  16. Konus-Wind observation of GRB 070420
  17. GRB 070411: break in the optical light curve
  18. GRB 070420 Swift-BAT Refined Analysis
  19. GRB 070420: optical rebrightening observed at Mt. John
  20. GRB070420: Swift UVOT continuing observations
  21. GRB 070420: Faulkes Telescope South Observations
  22. GRB 070420: TAROT La Silla observatory optical observations
  23. GRB 070420: NIR and optical afterglow confirmed
  24. GRB 070420: Swift detection of a burst with optical afterglow
  25. GRB 070419A: MITSuME Okayama Observations
  26. GRB 070419A: Early Super-LOTIS Observations
  27. GRB 070419B, Swift-BAT refined analysis
  28. GRB 070419A Swift-BAT Refined Analysis
  29. GRB 070419A, Optical observations
  30. GRB070419 - SDSS Pre-Burst Observations
  31. GRB 070419A: SARA observations
  32. GRB 070419A: NAYUTA Optical Observation
  33. GRB 070419B optical afterglow candidate
  34. GRB 070419A: Optical and IR observations with KANATA
  35. GRB 070419B: optical afterglow candidate
  36. GRB070419A, optical observation
  37. Infrared detection of GRB070419A with UKIRT
  38. GRB 070419A: Kiso Optical observation
  39. GRB 070419: P60 Confirmation of Optical Afterglow
  40. GRB 070419B: Swift detection of a burst
  41. GRB 070419A: ROTSE-III Optical Limits
  42. GRB 070419: Swift detection of a burst
  43. GRB 070418: Optical and IR observations with KANATA
  44. Trigger 276045: Swift detection of a possible burst
  45. GRB 070406: Swift XRT refined analysis
  46. GRB070412: UKIRT-WFCAM JHK upper limits
  47. GRB070412: Swift UVOT observations
  48. GRB 070411: Swift/UVOT observations
  49. GRB 070412, Swift-BAT refined analysis
  50. GRB 070412 Liverpool Telescope optical limit
  51. GRB 070412: Optical observations at Crni Vrh
  52. GRB 070412: further NOT observations
  53. GRB 070412: Gemini/GMOS afterglow candidate
  54. GRB 070412: IAC80 optical afterglow candidate
  55. GRB 070412: NOT observations
  56. GRB 070411, Swift-BAT refined analysis
  57. GRB 070412: Swift detection of a burst
  58. GRB 070411: IAC80 optical observations
  59. GRB 070411 : Liverpool Telescope Observations
  60. GRB 070411: Swift detection of a burst with optical afterglow
  61. GRB 070406: Swift XRT team further analysis
  62. Suzaku ToO observation of SGR 1806-20
  63. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  64. GRB 070406, Swift-BAT refined analysis
  65. GRB 070406: Correction to the optical candidate in GCN6253
  66. GRB 070406: Gemini South Imaging and XRT analysis
  67. GRB070406: Swift UVOT observations
  68. GRB 070406: further analysis of NOT images.
  69. Short GRB 070406 - Possible Bright Host Galaxy
  70. GRB 070406: NOT observations
  71. GRB 070406: Optical candidate
  72. GRB 070406: SARA upper limit
  73. GRB 070406: Xinglong TNT optical Upper Limit
  74. GRB 070402: Suzaku WAM observation of the prompt emission
  75. GRB 070328: Suzaku WAM observation of the prompt emission
  76. UVOT observations of GRB070330
  77. GRB 070330, Swift-BAT refined analysis
  78. GRB 070330: TAROT La Silla observatory optical observations
  79. GRB 070330 - Watcher Observations
  80. GRB 070330: Swift detection of a burst
  81. GRB 070328: Swift/UVOT Upper Limits
  82. long burst from SGR 1806-20 detected on March 26
  83. GRB 070328: Swift/XRT Refined Analysis
  84. GRB 070328 : Suzaku ToO follow up starts
  85. GRB 070328, Swift-BAT refined analysis
  86. GRB 070328: Swift detection of a burst
  87. GRB 070311, deep optical photometry
  88. Short-Hard GRB 070209: PROMPT Observations
  89. GRB 070318: absorption-line redshift
  90. GRB070318: Swift UVOT continuing observations
  91. GRB 070318, Swift-BAT refined analysis
  92. GRB 070318: Swift detection of a burst with an optical afterglow
  93. GRB 070311: Late Central Engine Activity Optical Flare??
  94. VLA observation of GRB 070311
  95. GRB 070311: Optical observation.
  96. GRB 070306: possible emission-line redshift
  97. GRB 070311: SARA upper limit
  98. GRB 070309: variability of the XRT afterglow candidate
  99. GRB070311: FRAM early follow-up limit
  100. GRB 070311: P60 Observations

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