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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"

17850 results found.

  1. GRB 080623: GROND upper limits
  2. GRB 080623: Enhanced Swift-XRT position
  3. GRB 080623: TAROT La Silla observatory optical observations
  4. GRB 080623: Swift XRT prompt analysis
  5. Swift-BAT trigger 314975 possible burst
  6. GRB080607: optical observation
  7. GRB 070809: Putative host galaxy and redshift
  8. VLA upper limit on INTEGRAL burst GRB 080613A
  9. GRB080613B: MITSuME upper limits
  10. GRB080613A: Optical upper limits with Okayama MITSuME telescope
  11. GRB 080603A: optical observations on June 04
  12. GRB 080613A: GROND Confirmation of the Afterglow Candidate
  13. GRB 080613B: GROND Upper Limits
  14. GRB 080613B - NOT optical and IR nondetections
  15. GRB 080613B: Swift-XRT refined analysis
  16. GRB 080514B: Spectroscopic constraints and probable host galaxy
  17. GRB 080613B: Swift detection of a burst
  18. GRB 080613: Faulkes Telescope North optical candidate
  19. GRB 080603A: Late-time Keck imaging and spectroscopy
  20. GRB 080603b: optical observation
  21. GRB 080607: AGILE-MCAL observation of the prompt emission
  22. GRB 080603B - TLS 2nd Epoch: Another Break
  23. GRB 080605: TLS 3rd Epoch - Source Confusion
  24. GRB080605: optical observation with the MITSuME-OAO telescope
  25. GRB080607: RTT150 optical observations
  26. GRB 080603A: optical observations
  27. GRB 080607: Swift-XRT refined analysis
  28. VLA detection of INTEGRAL burst GRB 080603A
  29. GRB 080607: Enhanced Swift-XRT position
  30. GRB 080605: GROND 2nd epoch observations
  31. GRB 080607: Keck/LRIS spectroscopy and redshift
  32. GRB 080607: Swift detection of a burst with optical afterglow
  33. Possible VLA radio detection on INTEGRAL burst GRB 080603A
  34. GRB 080604: VLA radio upper limit
  35. GRB 080603B: VLA radio upper limit
  36. GRB 080605: MASTER VWF 46 s AT observation
  37. GRB 080605: Enhanced Swift-XRT position
  38. GRB 080605: GROND detection of the optical afterglow candidate
  39. GRB 080605: Liverpool Telescope optical afterglow candidate
  40. GRB 080605: Swift/UVOT Position of the Optical Afterglow
  41. GRB 080605: Swift detection of a burst with an optical afterglow
  42. GRB 080603B: TLS Afterglow Observation
  43. GRB 080603A: TLS Afterglow Observation
  44. GRB 080604: MITSuME Okayama observation
  45. GRB 080604: Swift-XRT refined analysis
  46. GRB 080603B : Liverpool Telescope Observations
  47. GRB 080603A: Swift-XRT detection of the afterglow
  48. GRB 080604: Enhanced Swift-XRT position
  49. GRB 080604: Swift detection of a burst with an optical afterglow
  50. GRB 080603B: TAROT Calern observatory confirmation of slow optical decay
  51. GRB 080516: TAROT La Silla observatory optical observations
  52. GRB080603B: NOT redshift
  53. GRB 080603B: BOOTES2/TELMA optical observations
  54. GRB 080603B: TAROT Calern observatory detection of a plateau in the light curve
  55. GRB 080603B: Swift detection of a burst with optical afterglow
  56. Possible GRB080603: Faulkes Telescope North optical afterglow candidate
  57. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  58. GRB 080602: Swift-XRT refined analysis
  59. GRB 080602: NOT R-band upper limit
  60. GRB 080602: Enhanced Swift-XRT position
  61. GRB 080602: Swift detection of a burst
  62. Swift analysis of BAT Slew Survey event (Trigger=009)
  63. GRB 080523: afterglow confirmation and redshift constraints
  64. GRB 080524: Swift XRT and UVOT analysis
  65. GRB 080503: 2nd Epoch Chandra X-ray Observations
  66. GRB 080524: Swift-BAT detection of a burst in ground analysis
  67. GRB 080523: VLT optical observations
  68. GRB 080523: Enhanced Swift-XRT position
  69. GRB 080523: Swift detection of a burst
  70. GRB 080515: KPNO 4m NIR afterglow detection
  71. GRB 80516: Swift/UVOT Observations
  72. GRB 080515: Swift-XRT position and analysis
  73. GRB 080514B: UVOT Observations
  74. GRB080520: Swift/UVOT observations
  75. GRB 080520, GROND observations
  76. GRB 080520: Enhanced Swift-XRT position
  77. GRB 080520: Swift XRT Refined Analysis
  78. GRB 080520: Swift detection of a burst with optical afterglow
  79. GRB 080514B: second epoch Swift XRT data confirms the X-ray afterglow
  80. GRB 080514B: Further NIR observations
  81. GRB 080517: Enhanced Swift-XRT position
  82. GRB080517: Liverpool Telescope Optical Observations
  83. GRB 080517: Swift detection of a burst
  84. GRB 080516, GROND 2nd epoch observations
  85. GRB 080516, GROND observations
  86. GRB 080516, SMARTS optical/IR observations
  87. GRB 080516: Enhanced Swift-XRT position
  88. GRB 080516: Swift detection of a burst
  89. Errartum: VLA upper limit on GRB 080507
  90. VLA upper limit on GRB 080705
  91. IPN triangulation of bright GRB 080513
  92. GRB 080514B: slow fading behaviour ?
  93. GRB 080514B: Swift-XRT analysis
  94. GRB 080514B, GROND observations
  95. GRB 080515: Swift detection of a burst
  96. GRB 080514B: Watcher observations
  97. GRB 080514B: SuperAGILE/IPN GRB Localization
  98. Swift detection of a possible galactic transient
  99. GRB080514: REM NIR & Optical Observations
  100. GRB 080506: NAYUTA Optical Observation

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