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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"

6186 results found.

  1. GRB070208: optical observations
  2. IPN localization of very intense short GRB 070201
  3. GRB 070208: Swift XRT refined analysis
  4. GRB 070208: RAPTOR detection of early afterglow onset
  5. GRB 070208: Early IR detection and afterglow astrometry
  6. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  7. GRB061217: MAGIC telescope GeV observation
  8. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  9. GRB070124: Swift-XRT Observation
  10. GRB070125: Swift-XRT Refined Analysis
  11. RHESSI Spectrum of GRB070125
  12. GRB 070110: Ep,i - Eiso correlation
  13. GRB 070110 declared a "Burst of Interest" by Swift team
  14. GRB070110: Swift XRT Team refined analysis
  15. GRB070107: Swift/XRT refined analysis
  16. GRB070103: Swift XRT refined analysis
  17. GRB061222a: optical observations
  18. GRB 061210: Swift/XRT Astrometry Correction
  19. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  20. GRB 061222A: Gemini Afterglow Candidate
  21. GRB 061217: Extended object in the revised XRT error circle
  22. GRB061210: Swift/UVOT observations
  23. Optical Afterglow observations of GRB 061126
  24. GRB061126: optical observations
  25. GRB061126: update on the Swift-XRT afterglow light curve
  26. GRB 061201: Swift XRT Team refined analysis
  27. GRB 061201, Swift-BAT refined analysis of the SHB
  28. GRB061126: Optical afterglow observations from MIRO
  29. GRB 061126: Swift-XRT refined analysis
  30. GRB 061126: SARA Observations
  31. GRB 061126: Early Detection of the IR Afterglow
  32. GRB 061121: MDM Optical Decay
  33. GRB061122: Swift-XRT position
  34. GRB 061121: MDM Optical Observations
  35. GRB061028: MAGIC telescope GeV observation
  36. GRB 061028: Swift/XRT Astrometry Correction
  37. GRB 061004: Further VLT/NTT observations
  38. GRB 061028: Optical R passband observations
  39. GRB 061004: Swift/XRT Astrometry Correction
  40. GRB 060801: Swift/XRT Astrometry Correction
  41. GRB 061028: SARA upper limit
  42. GRB061028: XRT refined analysis
  43. GRB 061028, Swift-BAT refined analysis
  44. GRB 061027, Swift refined analysis of a possible burst
  45. GRB061025: Swift XRT refined analysis
  46. GRB 061021: Swift-XRT refined analysis
  47. GRB061019: Swift XRT refined analysis
  48. GRB 061006: astrometry-corrected XRT position
  49. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  50. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  51. GRB 061006: Swift-XRT Team Refined Analysis
  52. GRB 061004: Swift-XRT Team Refined Analysis
  53. GRB 061004: Nearby 2MASS Galaxy
  54. GRB 060928: Swift observations
  55. GRB 061002: Swift-XRT Team Refined Analysis
  56. GRB 060927: Early color
  57. GRB 060927: Swift XRT Team refined analysis
  58. GRB 060926: Swift XRT refined analysis
  59. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  60. GRB 060923C: Swift XRT refined analysis
  61. GRB 060923A: Keck and Gemini Observations
  62. GRB 060919, Swift-BAT refined analysis
  63. GRB060919: XRT refined analysis
  64. GRB 060919: Swift detection of a burst
  65. GRB060825: MAGIC telescope GeV observation
  66. GRB 060912: Swift XRT Team Refined Analysis
  67. GRB 060908, Swift/XRT refined analysis
  68. GRB 060904B : CFHT/WIRCam NIR afterglow observations
  69. GRB 060904A : Optical limit
  70. GRB 060904A: Subaru NIR observation
  71. GRB 060904B: Swift-XRT refined analysis
  72. GRB 060904A: Swift-XRT refined analysis
  73. GRB 060901: Swift/XRT Refined Analysis
  74. GRB 060605, observations using an Integral Field Unit
  75. GRB060729: analysis of XMM-Newton observation
  76. GRB060814: Break in the XRT light curve
  77. GRB060813: Break in the XRT light curve
  78. GRB 060814: P200 NIR Observations
  79. GRB 060814: Swift XRT refined analysis
  80. GRB060813: Swift/UVOT upper limits
  81. GRB 060813: Swift XRT refined analysis
  82. A dust-scattering halo detected around SGR 1806-20
  83. GRB 060729: An update on the Swift XRT and UVOT observations
  84. GRB 060805B: XRT Team Analysis
  85. GRB 060807: XRT Team refined analysis
  86. GRB 060807: Kanazawa R-band observation
  87. GRB060805 Liverpool Telescope observations
  88. GRB 060805: XRT Team Refined Analysis
  89. GRB 060801: Swift XRT refined analysis
  90. GRB 060801: Kanazawa Optical Observation
  91. GRB 060729: Swift-XRT refined analysis
  92. GRB 060719: near-infrared afterglow
  93. GRB 060719: VLT/ISAAC observations
  94. GRB 060719: XRT refined analysis
  95. GRB 060719: LCO optical observations
  96. GRB 060717: Swift XRT refined analysis
  97. GRB 060714: OA fading and a possible host detection
  98. GRB 060714: Swift XRT refined analysis
  99. GRB 060712: XRT refined analysis
  100. GRB 060712: XRT refined position

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