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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"

32501 results found.

  1. GRB 070330, SMARTS optical/IR observations
  2. GRB 070330: Swift-XRT refined analysis
  3. GRB 070330 - Watcher Observations
  4. Konus-Wind observation of GRB 070328
  5. GRB 070328: Swift/UVOT Upper Limits
  6. long burst from SGR 1806-20 detected on March 26
  7. GRB 070328: Swift/XRT Refined Analysis
  8. GRB 070328 : Suzaku ToO follow up starts
  9. GRB 070328, Swift-BAT refined analysis
  10. GRB070220: optical observations
  11. GRB070208: optical observations
  12. GRB070223: confirmation of nIR and optical afterglow
  13. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  14. GRB 070311, deep optical photometry
  15. Short-Hard GRB 070209: PROMPT Observations
  16. GRB 070318: Gemini + Magellan spectra
  17. GRB 070318: absorption-line redshift
  18. GRB070318: Swift UVOT continuing observations
  19. GRB070318: Swift-XRT refined analysis
  20. GRB 070318: Swift/UVOT Continued Observations
  21. GRB 070318, Swift-BAT refined analysis
  22. GRB 070311: Late Central Engine Activity Optical Flare??
  23. GRB 070311: MDM Optical Monitoring
  24. VLA observation of GRB 070311
  25. GRB 070311: Tautenburg sees afterglow fading
  26. GRB 070311: Optical observation.
  27. GRB 070311: Optical Brightening
  28. GRB 070306: possible emission-line redshift
  29. GRB 070311: SARA upper limit
  30. GRB 070309: variability of the XRT afterglow candidate
  31. GRB 070311: MDM Optical Follow-up
  32. GRB 070311: RAPTOR Detection of Optical Emission
  33. GRB070311: FRAM early follow-up limit
  34. GRB 070311: P60 Observations
  35. GRB 070311: MDM Optical Detection
  36. GRB 070311: Swift/UVOT Upper Limits
  37. GRB 070311: MITSuME Okayama Optical Observation
  38. GRB 070311: Swift-XRT refined analysis
  39. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  40. GRB 070311: REM candidate afterglow
  41. GRB060901: Candidate optical afterglow
  42. GRB070309: Swift/XRT possible afterglow detection
  43. GRB 070125: Chandra X-ray Confirmation of Jet Break
  44. GRB 070309: Swift/UVOT Upper Limits
  45. GRB 070306, optical observation
  46. Swift UVOT Finding Charts for GRB 070309
  47. GRB 070125: X-ray light curve analysis
  48. VLA observation of GRB 070306
  49. GRB 070306: NOT observations
  50. GRB 070306 Swift/UVOT refined analysis
  51. GRB070306: confirmation of near infrared afterglow
  52. GRB 070306: ART-3 early optical and near infrared constraints
  53. GRB 070306, Swift-BAT refined analysis
  54. GRB 070306: XRT Team Refined Analysis
  55. GRB 070306: Optical and IR observations with KANATA
  56. GRB 070223: NIR observations at WHT
  57. GRB070227: Swift-XRT refined analysis
  58. GRB 060605 new redshift
  59. GRB 070125, deep late-time optical observation
  60. VLA observation of GRB 070224
  61. GRB 070223: Optical Observations
  62. GRB 070227: optical observations
  63. GRB 070227: Swift/UVOT Upper Limits
  64. GRB 070227, Swift-BAT refined analysis
  65. GRB070227: possible X-ray afterglow detection
  66. GRB 070224: Optical afterglow confirmation
  67. GRB 070224: Swift/UVOT Upper Limits
  68. GRB070224: Swift-XRT Astrometrically Corrected Position
  69. VLA observation of GRB 070223
  70. VLA observation of GRB 070220
  71. GRB070224: Magellan Imaging Observations
  72. GRB 070224: WHT K-band imaging
  73. GRB 070224: MDM Observations
  74. GRB070224: Gemini Imaging Observations
  75. GRB070224: Swift-XRT Refined Analysis
  76. GRB 070224: optical afterglow candidate
  77. GRB 070224, Swift-BAT refined analysis
  78. GRB 070224: MASTER-Net refind analysis
  79. GRB 070224: MASTER-VWF-Kislovodsk observations
  80. GRB 070223: Optical observations
  81. RHESSI Spectrum of GRB070220
  82. GRB070223: Swift/UVOT refined analysis
  83. GRB 070223: Optical-IR observation with KANATA
  84. GRB 070223, Swift-BAT refined analysis
  85. GRB070223: MASTER-VWF-Kislovodsk observations
  86. GRB 070223: Swift-XRT Refined Analysis
  87. GRB070223 - SDSS Pre-Burst Observations
  88. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  89. GRB 070223: MDM Observations
  90. Konus-Wind and Konus-A observations of GRB 070220
  91. GRB 070220: MITSuME Okayama Optical Observation
  92. GRB 070220: ART-3 Optical and NIR limits
  93. GRB 070220 Swift-BAT Refined Analysis
  94. Swift/UVOT refined analysis of GRB070220
  95. GRB 070209: Swift XRT refined analysis
  96. GRB 070220: Swift-XRT Refined Analysis
  97. GRB 070220: Observation with the KANATA 1.5m telescope
  98. GRB 070219: Gemini Observations
  99. GRB 070220 : Faulkes Telescope North optical limit
  100. GRB070219: MASTER-VWF-Kislovodsk observations

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