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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"

6094 results found.

  1. GRB 070223: Optical-IR observation with KANATA
  2. GRB 070223: Swift-XRT Refined Analysis
  3. Konus-Wind and Konus-A observations of GRB 070220
  4. GRB 070209: Swift XRT refined analysis
  5. GRB 070219: XRT Refined Analysis
  6. GRB 070219: Liverpool Telescope Observations
  7. GRB 070125 observations with the GMRT
  8. GRB 070209: Swift XRT analysis
  9. GRB070208: optical observations
  10. IPN localization of very intense short GRB 070201
  11. GRB 070208: Swift XRT refined analysis
  12. GRB 070208: RAPTOR detection of early afterglow onset
  13. GRB 070208: Early IR detection and afterglow astrometry
  14. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  15. GRB061217: MAGIC telescope GeV observation
  16. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  17. GRB070124: Swift-XRT Observation
  18. GRB070125: Swift-XRT Refined Analysis
  19. RHESSI Spectrum of GRB070125
  20. GRB 070110: Ep,i - Eiso correlation
  21. GRB 070110 declared a "Burst of Interest" by Swift team
  22. GRB070110: Swift XRT Team refined analysis
  23. GRB070107: Swift/XRT refined analysis
  24. GRB070103: Swift XRT refined analysis
  25. GRB061222a: optical observations
  26. GRB 061210: Swift/XRT Astrometry Correction
  27. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  28. GRB 061222A: Gemini Afterglow Candidate
  29. GRB 061217: Extended object in the revised XRT error circle
  30. GRB061210: Swift/UVOT observations
  31. Optical Afterglow observations of GRB 061126
  32. GRB061126: optical observations
  33. GRB061126: update on the Swift-XRT afterglow light curve
  34. GRB 061201: Swift XRT Team refined analysis
  35. GRB 061201, Swift-BAT refined analysis of the SHB
  36. GRB061126: Optical afterglow observations from MIRO
  37. GRB 061126: Swift-XRT refined analysis
  38. GRB 061126: SARA Observations
  39. GRB 061126: Early Detection of the IR Afterglow
  40. GRB 061121: MDM Optical Decay
  41. GRB061122: Swift-XRT position
  42. GRB 061121: MDM Optical Observations
  43. GRB061028: MAGIC telescope GeV observation
  44. GRB 061028: Swift/XRT Astrometry Correction
  45. GRB 061004: Further VLT/NTT observations
  46. GRB 061028: Optical R passband observations
  47. GRB 061004: Swift/XRT Astrometry Correction
  48. GRB 060801: Swift/XRT Astrometry Correction
  49. GRB 061028: SARA upper limit
  50. GRB061028: XRT refined analysis
  51. GRB 061028, Swift-BAT refined analysis
  52. GRB 061027, Swift refined analysis of a possible burst
  53. GRB061025: Swift XRT refined analysis
  54. GRB 061021: Swift-XRT refined analysis
  55. GRB061019: Swift XRT refined analysis
  56. GRB 061006: astrometry-corrected XRT position
  57. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  58. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  59. GRB 061006: Swift-XRT Team Refined Analysis
  60. GRB 061004: Swift-XRT Team Refined Analysis
  61. GRB 061004: Nearby 2MASS Galaxy
  62. GRB 060928: Swift observations
  63. GRB 061002: Swift-XRT Team Refined Analysis
  64. GRB 060927: Early color
  65. GRB 060927: Swift XRT Team refined analysis
  66. GRB 060926: Swift XRT refined analysis
  67. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  68. GRB 060923C: Swift XRT refined analysis
  69. GRB 060923A: Keck and Gemini Observations
  70. GRB 060919, Swift-BAT refined analysis
  71. GRB060919: XRT refined analysis
  72. GRB 060919: Swift detection of a burst
  73. GRB060825: MAGIC telescope GeV observation
  74. GRB 060912: Swift XRT Team Refined Analysis
  75. GRB 060908, Swift/XRT refined analysis
  76. GRB 060904B : CFHT/WIRCam NIR afterglow observations
  77. GRB 060904A : Optical limit
  78. GRB 060904A: Subaru NIR observation
  79. GRB 060904B: Swift-XRT refined analysis
  80. GRB 060904A: Swift-XRT refined analysis
  81. GRB 060901: Swift/XRT Refined Analysis
  82. GRB 060605, observations using an Integral Field Unit
  83. GRB060729: analysis of XMM-Newton observation
  84. GRB060814: Break in the XRT light curve
  85. GRB060813: Break in the XRT light curve
  86. GRB 060814: P200 NIR Observations
  87. GRB 060814: Swift XRT refined analysis
  88. GRB060813: Swift/UVOT upper limits
  89. GRB 060813: Swift XRT refined analysis
  90. A dust-scattering halo detected around SGR 1806-20
  91. GRB 060729: An update on the Swift XRT and UVOT observations
  92. GRB 060805B: XRT Team Analysis
  93. GRB 060807: XRT Team refined analysis
  94. GRB 060807: Kanazawa R-band observation
  95. GRB060805 Liverpool Telescope observations
  96. GRB 060805: XRT Team Refined Analysis
  97. GRB 060801: Swift XRT refined analysis
  98. GRB 060801: Kanazawa Optical Observation
  99. GRB 060729: Swift-XRT refined analysis
  100. GRB 060719: near-infrared afterglow

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