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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"
  1. GRB 070508, SMARTS optical afterglow observation
  2. GRB 070508, Swift-BAT refined analysis
  3. GRB 070508: Multicolor optical observations and possible redshift limit
  4. GRB 070508: Swift-XRT refined analysis
  5. GRB 070508: Optical observation limiting magnitude
  6. GRB 070508: Optical afterglow detection
  7. GRB 070508: REM observations
  8. GRB 070508: TAROT La Silla observatory optical observations
  9. GRB 070508: Swift detection of an intense burst with an optical counterpart
  10. GRB070412: MAGIC telescope GeV observation
  11. Swift-BAT trigger 278809 is not a GRB
  12. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  13. GRB 070506: VLT redshift
  14. GRB070506: Swift/UVOT Observations
  15. GRB070506: Swift XRT refined analysis
  16. GRB 070506, Swift-BAT Refined Analysis
  17. GRB 070506: Swift detection of a burst with optical afterglow
  18. GRB 070412, deep LBT imaging
  19. GRB 070429A: Swift XRT further analysis
  20. GRB070429B: VLT observations
  21. GRB 070429A: optical observations
  22. GRB070429B: position correction
  23. GRB 070309: Swift-XRT afterglow confirmation
  24. GRB070429B: possible host galaxy detection
  25. VLA observation of GRB 070429B
  26. Swift/UVOT observations of GRB070429B
  27. GRB 070429B, Swift-BAT refined analysis
  28. Swift/UVOT observations of GRB070429A
  29. GRB 070429A: Swift XRT refined analysis
  30. GRB 070429A, Swift-BAT refined analysis
  31. GRB 070429A: optical and NIR observations
  32. GRB 070429B: Swift XRT refined analysis
  33. GRB 070429B: ROTSE-III Optical Limits
  34. GRB 070429B: Swift detection of a short burst
  35. GRB 070429: What's the temperature?
  36. GRB 070429: ROTSE-III Optical Limits
  37. GRB 070429: Swift detection of a burst
  38. GRB 070427, Swift-BAT Refined Analysis
  39. LT monitoring of GRB070412
  40. GRB 070427: Swift detection of a burst
  41. GRB 070411, further deep LBT photometry
  42. GRB 070411: Late-time Keck imaging
  43. GRB 070411 : Planned XMM-Newton observation
  44. GRB070419B: Suzaku WAM observation of the prompt emission
  45. GRB 070420, SMARTS optical/IR afterglow observations
  46. GRB 070411, deep LBT photometry
  47. GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
  48. Konus-Wind observation of GRB 070420
  49. GRB 070411: break in the optical light curve
  50. GRB 070420 Swift-BAT Refined Analysis
  51. GRB070419A: Kuiper Optical detection
  52. GRB070419a: Swift UVOT observations
  53. GRB 070419A: MARGE Observations
  54. GRB 070420: optical rebrightening observed at Mt. John
  55. GRB 070420: Swift XRT refined analysis
  56. GRB070420: Swift UVOT continuing observations
  57. GRB 070411: BART early limit
  58. GRB 070420: Faulkes Telescope South Observations
  59. GBR 070419A: Swift/XRT refined analysis
  60. GRB 070420: TAROT La Silla observatory optical observations
  61. GRB 070420: NIR and optical afterglow confirmed
  62. GRB 070420: Swift detection of a burst with optical afterglow
  63. GRB 070419A: MITSuME Okayama Observations
  64. GRB 070419A: Early Super-LOTIS Observations
  65. GRB 070419B, Swift-BAT refined analysis
  66. GRB 070419A Swift-BAT Refined Analysis
  67. GRB070419B: Confirmation of Optical Transient
  68. GRB 070419A: RAPTOR Detection of Early Emission
  69. GRB 070419B: Swift XRT refined analysis
  70. GRB 070419: Keck/LRIS Absorption Redshift
  71. GRB 070419B: optical afterglow confirmation
  72. GRB 070419A, Optical observations
  73. GRB 070411: Deep VLT detection
  74. GRB070419 - SDSS Pre-Burst Observations
  75. GRB 070419A: SARA observations
  76. GRB 070419A: NAYUTA Optical Observation
  77. GRB 070419A: Faulkes Telescope North Optical Observations
  78. GRB 070419B optical afterglow candidate
  79. GRB 070419A: Optical and IR observations with KANATA
  80. GRB 070419B: optical afterglow candidate
  81. GRB 070419A: Lulin Optical observation
  82. GRB070419A, optical observation
  83. Infrared detection of GRB070419A with UKIRT
  84. GRB 070419A: Kiso Optical observation
  85. GRB070330: Correction to UVOT position
  86. GRB 070419: P60 Confirmation of Optical Afterglow
  87. GRB 070419B: Swift detection of a burst
  88. GRB 070419 optical afterglow candidate
  89. GRB 070419A: ROTSE-III Optical Limits
  90. GRB 070419: Swift detection of a burst
  91. Swift-BAT Trigger 276045 is a Cosmic Ray Shower event
  92. GRB 070418: Optical and IR observations with KANATA
  93. Trigger 276045: Swift detection of a possible burst
  94. GRB 070406: Swift XRT refined analysis
  95. IBAS Alert n.4202: not a real GRB
  96. GRB 070318, SMARTS optical/IR afterglow observations
  97. GRB 070411: TLS data shows plateau, flares
  98. GRB070412: UKIRT-WFCAM JHK upper limits
  99. GRB070412: Swift UVOT observations
  100. IBAS Alert n.4199: Not a GRB

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