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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"

37518 results found.

  1. GRB 061004: Swift/XRT Astrometry Correction
  2. GRB 060801: Swift/XRT Astrometry Correction
  3. GRB 061028: Futher P200 Observations
  4. GRB 061028: MDM Observations
  5. GRB 061028: P200 Observations
  6. GRB 061028: SARA upper limit
  7. GRB 061028: z band imaging
  8. GRB061028: XRT refined analysis
  9. GRB 061028: Swift/UVOT Observations
  10. GRB 061028, Swift-BAT refined analysis
  11. GRB 061028: TAROT Calern observatory late optical observations
  12. GRB 061028: TAROT Calern observatory optical observations
  13. GRB 061028: Swift detection of a burst
  14. GRB 061027, Swift refined analysis of a possible burst
  15. GRB 061027: Swift detection of a possible burst
  16. GRB061025: Swift/UVOT observations
  17. GRB 061019: MITSuME upper limits
  18. GRB 061025: REM observations
  19. GRB 061025: Gemini-S observations
  20. GRB061025: Swift XRT position
  21. GRB 061025: ROTSE-III Optical Limits
  22. GRB 061025: a long GRB detected by INTEGRAL
  23. GRB 061021, Swift-BAT Lag analysis
  24. Konus-Wind observation of GRB 061021
  25. GRB 061021 - VLT spectrum without lines
  26. GRB 061021: Swift-XRT refined analysis
  27. GRB 061021: Swift/UVOT Observation
  28. GRB 061021, Swift-BAT refined analysis
  29. GRB 061021: Swift detection of a burst
  30. GRB 061019: Super-LOTIS upper limit
  31. GRB060904b: optical observations
  32. GRB061019: optical observations
  33. GRB061019: optical observations
  34. GRB 061019: SARA upper limit
  35. GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
  36. GRB 060930: MARGE Optical Limits
  37. GRB 061019: Swift/UVOT upper limit
  38. GRB 061019: SMARTS afterglow confirmation
  39. GRB061019: Swift XRT refined analysis
  40. GRB 061019, Swift-BAT refined analysis
  41. GRB 061019: TAROT La Silla observatory optical observations
  42. GRB 061019: REM K-band candidate afterglow
  43. GRB061019: Swift/XRT position
  44. GRB 061019: Swift-BAT detection of a burst
  45. GRB 060825: GORT Observations
  46. GRB 061007: Second Epoch ATCA Radio Observations
  47. GRB 061007: RHESSI Spectral Fit
  48. GRB 061007: Suzaku/WAM observation of the prompt emission
  49. GRB 061006: astrometry-corrected XRT position
  50. Konus-Wind observation of GRB 061007
  51. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  52. GRB 061007: ATCA Radio Observations
  53. GRB 061006: optical afterglow
  54. GRB 061006 : Suzaku/WAM observation of the prompt emission
  55. GRB 061007: OA fading and VLT redshift
  56. GRB 061007: Magellan Spectroscopy
  57. GRB 061007: Correction to GCN 5712
  58. GRB 061007: Swift-BAT refined analysis
  59. GRB 061007: Swift XRT refined analysis
  60. GRB 061006: Swift/UVOT optical observations
  61. Konus-Wind observation of the short hard GRB 061006
  62. GRB 061007 - FTS early brightening and power law decay
  63. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  64. GRB 061007: Swift detection of a burst with an optical counterpart
  65. GRB 061007: ROTSE-III Detection of Optical Counterpart
  66. GRB 061006: VLT observation
  67. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  68. GRB 061006: Swift-XRT Team Refined Analysis
  69. GRB061006 (Swift 232585) might be a short-hard GRB
  70. GRB 060930: near-IR afterglow candidate retraction
  71. GRB061006: Faulkes Telescope South Observations
  72. GRB 061006: Swift detection of a burst
  73. GRB 061004: Optical afterglow candidate and redshift
  74. GRB 061004: Las Campanas Optical/NIR Observations
  75. GRB 061004: Swift-XRT Team Refined Analysis
  76. GRB 061004, Swift BAT refined analysis
  77. GRB 061004: Nearby 2MASS Galaxy
  78. GRB 060928: Correction to GCN 5690
  79. GRB 061004: Swift detection of a burst
  80. GRB 060928: 2 pseudo-z from 2 detections spectral parameters
  81. Konus-Wind observation of GRB 060928
  82. GRB 060928: Suzaku/WAM observation of the prompt emission
  83. GRB 060928: Swift observations
  84. GRB 060928: RHESSI Spectral Fit
  85. IPN triangulation of GRB060928 (long, exceptionally bright)
  86. GRB 060930: near-IR afterglow candidate
  87. GRB 061002: Swift-XRT Team Refined Analysis
  88. VLA observations of GRB 060926
  89. GRB061002 - SDSS Pre-Burst Observations
  90. GRB 061002, Swift-BAT refined analysis
  91. GRB061002: MASTER-VWF-Kislovodsk observations
  92. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  93. GRB 061002: Swift detection of a burst
  94. GRB 060908: Detection of a possible host
  95. GRB 060923A: Probable host galaxy in the R-band
  96. GRB 060807: Detection of a possible host galaxy
  97. GRB 060923A: VLA K-band Observations
  98. GRB060930: Faulkes Telescope South observation
  99. GRB 060930: Xinglong TNT optical observations
  100. GRB 060929: Further XRT Refined Analysis

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