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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"

21970 results found.

  1. GRB 070429A: Swift XRT refined analysis
  2. GRB 070429A: optical and NIR observations
  3. GRB 070429B: ROTSE-III Optical Limits
  4. LT monitoring of GRB070412
  5. GRB 070420, SMARTS optical/IR afterglow observations
  6. GRB 070411: break in the optical light curve
  7. GRB070419A: Kuiper Optical detection
  8. GRB070419a: Swift UVOT observations
  9. GRB 070419A: MARGE Observations
  10. GRB070420: Swift UVOT continuing observations
  11. GRB 070420: Faulkes Telescope South Observations
  12. GRB 070420: TAROT La Silla observatory optical observations
  13. GRB 070420: NIR and optical afterglow confirmed
  14. GRB 070419A: MITSuME Okayama Observations
  15. GRB 070419A: Early Super-LOTIS Observations
  16. GRB 070419A: RAPTOR Detection of Early Emission
  17. GRB 070419: Keck/LRIS Absorption Redshift
  18. GRB 070419B: optical afterglow confirmation
  19. GRB 070419A, Optical observations
  20. GRB070419 - SDSS Pre-Burst Observations
  21. GRB 070419A: SARA observations
  22. GRB 070419A: Faulkes Telescope North Optical Observations
  23. GRB 070419A: Optical and IR observations with KANATA
  24. GRB 070419B: optical afterglow candidate
  25. GRB 070419A: Lulin Optical observation
  26. GRB 070419A: Kiso Optical observation
  27. GRB 070419: P60 Confirmation of Optical Afterglow
  28. GRB 070418: Optical and IR observations with KANATA
  29. GRB 070406: Swift XRT refined analysis
  30. GRB 070318, SMARTS optical/IR afterglow observations
  31. GRB 070411: TLS data shows plateau, flares
  32. GRB070412: Swift UVOT observations
  33. GRB 070411: Swift/UVOT observations
  34. GRB 070412: Optical observations at Crni Vrh
  35. GRB 070412: further NOT observations
  36. GRB 070412: IAC80 optical afterglow candidate
  37. GRB 070412: NOT observations
  38. GRB 070412: Nearby bright galaxy
  39. GRB 070411: IAC80 optical observations
  40. GRB 070411 : Liverpool Telescope Observations
  41. GRB 070411: Optical observations at Crni Vrh
  42. GRB 070411: ROTSE-III Detection of Optical Counterpart
  43. GRB 070411: Tautenburg RRM Afterglow Confirmation
  44. GRB 070406: "Star" in XRT error circle S2 is an AGN?
  45. GRB 070406: Swift XRT team further analysis
  46. GRB 070406: Bright galaxy in XRT error circle is a quasar
  47. GRB 070406: Gemini South Imaging and XRT analysis
  48. GRB070406: Swift UVOT observations
  49. Short GRB 070406 - Possible Bright Host Galaxy
  50. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  51. GRB 070406: NOT observations
  52. GRB 070406: Optical candidate
  53. GRB 070406: photo-z of a bright galaxy in BAT error circle
  54. GRB 070311, deep optical photometry
  55. Konus-Wind and Konus-A observations of GRB 070402
  56. INTEGRAL ToO Observation of SGR1806-20
  57. UVOT observations of GRB070330
  58. GRB 070330, SMARTS optical/IR observations
  59. GRB 070330: TAROT La Silla observatory optical observations
  60. GRB 070330 - Watcher Observations
  61. GRB070220: optical observations
  62. GRB070208: optical observations
  63. GRB070223: confirmation of nIR and optical afterglow
  64. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  65. GRB 070311, deep optical photometry
  66. Short-Hard GRB 070209: PROMPT Observations
  67. GRB 070318: Gemini + Magellan spectra
  68. GRB 070318: absorption-line redshift
  69. GRB070318: Swift UVOT continuing observations
  70. GRB 070318: Swift/UVOT Continued Observations
  71. GRB 070311: MDM Optical Monitoring
  72. GRB 070311: Tautenburg sees afterglow fading
  73. GRB 070306: possible emission-line redshift
  74. GRB 070311: SARA upper limit
  75. GRB 070309: variability of the XRT afterglow candidate
  76. GRB 070311: P60 Observations
  77. GRB 070311: MDM Optical Detection
  78. GRB 070311: REM candidate afterglow
  79. GRB060901: Candidate optical afterglow
  80. GRB070309: Swift/XRT possible afterglow detection
  81. GRB 070125: Chandra X-ray Confirmation of Jet Break
  82. GRB 070125: X-ray light curve analysis
  83. GRB 070306: NOT observations
  84. GRB070306: confirmation of near infrared afterglow
  85. GRB 070306: IR observations and candidate afterglow
  86. GRB 070306: Optical and IR observations with KANATA
  87. GRB070306 - SDSS Pre-burst Observations
  88. GRB 070223: NIR observations at WHT
  89. GRB070227: Swift-XRT refined analysis
  90. GRB 070125, deep late-time optical observation
  91. GRB 070227: optical observations
  92. GRB 070223: Optical Observations
  93. GRB 070227: optical observations
  94. GRB 070227: Swift/UVOT Upper Limits
  95. GRB 070227: TAROT La Silla observatory optical observations
  96. GRB070227: possible X-ray afterglow detection
  97. GRB 920925C: optical afterglow candidate
  98. GRB 070224: Swift/UVOT Upper Limits
  99. GRB070224: Magellan Imaging Observations
  100. GRB 070224: MDM Observations

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