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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"

16158 results found.

  1. Subaru Observations of GRB050724
  2. GRB 050826: Optical Candidate
  3. GRB050824, HETE-2 Observation
  4. GRB050826: Swift/UVOT early upper limits
  5. GRB050824: First 2 hours of power low optical decay?
  6. Possible GRB050825:MASTER optical observations
  7. GRB050824: CORRECTION to UVOT observing times
  8. GRB050824: Swift/UVOT detection of fading afterglow
  9. GRB050824, I-band imaging
  10. GRB050824: Radio Observations
  11. GRB 050824: XRT refined analysis and possible afterglow detection
  12. GRB 050824: BAT refined analysis of a soft weak burst
  13. GRB050824: MASTER:OT decay
  14. GRB050805a: MASTER optical candidat
  15. GRB 050824: ROTSE-III Optical Limits
  16. GRB 050824 optical candidate
  17. GRB050820A: RTT150 optical observations
  18. GRB050815: Maidanak optical observation
  19. VLT/UVES spectroscopy of GRB050820
  20. GRB050820B at FRAM
  21. GRB050820A: RTT150 optical observations
  22. GRB 050820a - corrections to GCN 3846
  23. GRB 050822: ROTSE-III Prompt Optical Limits
  24. GRB050820A: Radio Observation
  25. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  26. GRB050820a BVRcIc field photometry
  27. GRB050820: refined XRT analysis
  28. GRB 050820 Swift-BAT refined analysis
  29. GRB 050820: P60 Temporal Decay Index
  30. GRB 050820: High Resolution Spectroscopy from Keck
  31. GRB050819: RTT150 optical observations
  32. GRB050820: Optical afterglow from P60
  33. GRB 050817: Optical observations
  34. GRB 050815: Radio Observation
  35. GRB050814: Radio Observation
  36. GRB050817: Negative Optical Observations
  37. GRB050817: Swift-BAT Detection of a burst
  38. GRB 050814: continued fading
  39. GRB050815: Optical afterglow detection by Swift UVOT
  40. GRB 050815: ROTSE-III Optical Limits
  41. GRB050814: Fading red source
  42. GRB050814: P60 Optical Afterglow Candidate
  43. GRB050813: RTT150 optical observations
  44. GRB 050813: KAIT optical limit
  45. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  46. GRB050803: CrAO optical observations, no OT candidate
  47. GRB 050807: ROTSE-III Optical Limits
  48. GRB 050730, optical observation
  49. GRB050805b: CrAO optical limit
  50. GRB050805a : Null detection report
  51. GRB050730, optical observations
  52. GRB050803, optical observations
  53. GRB 050805b: OHP optical limits
  54. GRB 050805b: TAROT optical limits
  55. GRB050805b: MASTER optical observations
  56. GRB050805a: MASTER optical candidat
  57. GRB050802: TNG optical observations
  58. GRB050803: Radio Observation
  59. GRB 050803: RTT150 optical observations
  60. GRB050801: Radio Observation
  61. GRB050730: Radio Detection
  62. GRB050803: CrAO optical observations, possible OT candidate
  63. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  64. GRB 050802.422: Fading of the afterglow and detection of the host
  65. GRB050803: MASTER further analys
  66. GRB 050803, optical observations
  67. GRB 050803: early Swift XRT analysis results
  68. GRB 050803: TAROT optical limits
  69. GRB050803: MASTER optical observations
  70. GRB050802: Tentative absorption redshift
  71. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  72. GRB 050802: Swift/UVOT optical and UV detections
  73. GRB050802: CrAO optical observations
  74. GRB050801: Unchanged decay slope
  75. GRB 050730: OHP optical observations
  76. GRB 050802 : Lulin Optical follow-up observation
  77. GRB050801: Optical photometry and decay index
  78. GRB050801: Swift/UVOT Optical and UV detections
  79. GRB 050801, SMARTS optical/IR afterglow observations
  80. GRB 050801: ROTSE-III Early Afterglow Break
  81. GRB 050730: early TAROT optical observations
  82. GRB 050730: RTT150 optical observations
  83. GRB 050730, spectra and optical photometry
  84. GRB 050730: Swift XRT afterglow observations
  85. GRB050730, afterglow observations
  86. GRB050730: confirmation of redshift
  87. GRB 050730, SMARTS optical/IR afterglow observations
  88. GRB050730: Liverpool Telescope optical observations
  89. GRB 050730, optical candidate
  90. GRB050730: Swift-BAT detection of a weak burst
  91. GRB 050713A: Swift XRT extended light curve
  92. GRB050713b: Maidanak optical observations
  93. GRB 050724: WHT optical observations
  94. GRB050726: Swift UVOT observations
  95. GRB050724: Refined Radio Position
  96. GRB 050724, SMARTS optical/IR afterglow observations
  97. GRB 050726, SMARTS optical/IR observations
  98. GRB 050727: RTT150 optical observations
  99. GRB050727: KAIT optical limit
  100. GRB050709: Second Epoch Chandra Observation

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