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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"

6791 results found.

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

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