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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').
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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"

28054 results found.

  1. GRB 051109A Optical Observations
  2. GRB 051111A : Lulin BVRI multi band afterglow observation
  3. GRB051111a: SARA Observations
  4. GRB 051111a: IR photometry
  5. GRB 051109B. Radio Observations
  6. GRB 051109A
  7. GRB051109A - radio observations
  8. GRB 051109B: Swift-BAT refined analysis
  9. GRB 051109A: Swift-UVOT Observations
  10. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  11. GRB051109B: no UVOT source detected
  12. GRB051109B: XRT refined analysis
  13. GRB 051109B : Lulin Optical Observations
  14. GRB 051109A : Lulin BVRI Optical afterglow observation
  15. GRB051109A: further steepening in the X-ray light curve
  16. GRB051109A: XRT refined analysis
  17. GRB 051109B: Super-LOTIS Observations
  18. GRB051105B: REM Optical observation
  19. GRB 051109B: Swift detection of a burst
  20. GRB 051109: Rc and Ic observations
  21. GRB 051109: Swift-BAT refined analysis
  22. GRB 051109a: IR Photometry and Astrometry
  23. GRB051109: Swift detection of a burst
  24. GRB 051109a: IR Detections
  25. GRB051105B: Swift/XRT upper limit
  26. GRB051105B: Swift/UVOT upper limit
  27. GRB051103: MASTER: OT limit and host galaxy candidates
  28. GRB051028: Swift-XRT refined analysis
  29. GRB 051105a, observation from Naini Tal and OSN
  30. GRB 051105a: MDM Observations
  31. GRB 051105A: TNG optical observations
  32. GRB051105A: Swift/UVOT Observations
  33. GRB 051105A, radio observations
  34. GRB051103:_MASTER_optical_observations
  35. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  36. GRB 051105A, optical observations
  37. XRT observations of GRB 051105A
  38. GRB 051105b: ART optical limits
  39. GRB 051105B (INTEGRAL 2701): Optical observation
  40. GRB 051105: Swift detection of a short burst
  41. Recent GRB UBVRcIc field photometry
  42. GRB051028 SARA Observation
  43. GRB051028: optical observations
  44. GRB051028: Swift/UVOT upper limits
  45. GRB051028: Swift XRT Position
  46. GRB051028:MASTER observations
  47. GRB051021B: Swift/UVOT Upper limits
  48. GRB 051021, Optical Observations
  49. GRB 051022: XRT Refined Spectral and Temporal Analysis
  50. GRB051012: Swift-XRT analysis
  51. GRB051021B: Swift XRT refined analysis
  52. GRB 051022, mm counterpart
  53. GRB 051022: Swift/UVOT Upper Limits
  54. GRB051022: Radio Counterpart
  55. GRB051022: IR observations
  56. GRB051021A: Swift XRT refined analysis
  57. GRB051022: Optical Observations
  58. GRB051021b: Magellan IR Imaging
  59. GRB 051021, SMARTS optical/IR observations
  60. GRB051022: Swift XRT Position
  61. GRB 051021: P200 Ks Observations
  62. GRB 051022 (=H3950): SXC Flight Localization is Valid
  63. GRB051021: Swift/UVOT Upper Limits
  64. GRB 051021B: Refined analysis of the Swift-BAT burst
  65. GRB 051022: SSO40 Optical Observations
  66. GRB051022,optical observation
  67. GRB 051021,optical observation
  68. GRB 051021B: Swift detection of a burst
  69. GRB 051021 : optical afterglow observation at Lulin
  70. GRB 051021: Optical observations and candidate afterglow
  71. GRB051021.63
  72. GRB051021.6: MASTER optical observation
  73. GRB051021: A GRB Localized by HETE
  74. Swift-BAT triggered on a posible CR Shower or possible GRB
  75. GRB 051016b: Optical limit
  76. Afterglow candidate of GRB 051016B observed at Lulin
  77. GRB 051016A: Swift/UVOT upper limits
  78. GRB 051016B: refined analysis of the Swift/XRT data
  79. GRB 051016B: Swift/UVOT detection
  80. GRB 051016B,optical observation
  81. GRB 051016B : Optical follow-up at Lulin
  82. GRB 051016B: Refined analysis of the Swift-BAT burst
  83. GRB 051016B: Swift detection of a soft burst
  84. GRB 051016: Swift-BAT refined analysis
  85. GRB051016 XMM-Newton observation
  86. GRB051016: Swift XRT refined analysis.
  87. GRB 051016: PROMPT Observations
  88. GRB051016: Swift detection of a burst
  89. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  90. GRB 051012: Swift-BAT detection of burst yesterday
  91. Swift-BAT Trigger 159578 is a possible burst
  92. GRB 051006: Swift/UVOT Upper Limits
  93. GRB051008: optical candidate
  94. GRB 051008 - a low redshift low-luminosity burst?
  95. GRB051011: bright nebulae near error box
  96. GRB051011: MASTER optical observation
  97. GRB051008: Final refined analysis of the Swift-BAT burst
  98. GRB051008: Radio Observation
  99. GRB 051008, optical observations
  100. GRB 051008: early Swift XRT analysis

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