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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3361 results found.

  1. SGR 0501+4516: optical observations in August
  2. GRB 081024B: BTA deep optical observations
  3. GRB 081028: CrAO optical observations
  4. GRB 081028B: Fermi GBM detection
  5. GRB 081021: Fermi GBM detection
  6. GRB 081028: optical observations at the NOT
  7. GRB 081028: Swift detection of a burst
  8. GRB 081025: TLS upper limits
  9. GRB 081025: Swift-XRT position
  10. GRB 081012: Swift/UVOT analysis of initial observations
  11. GRB 081012: ROTSE-III Optical Limits
  12. GRB 081012: Swift detection of a burst
  13. GRB 081011: Swift detection of a burst
  14. GRB 081007, Swift-BAT refined analysis
  15. GRB 080928: Fermi GBM detection
  16. Trigger 330353: Swift detection of a Galactic short soft burst
  17. GRB081001: optical limit from ASH-Centurion
  18. GRB 080928: Swift/UVOT observations
  19. GRB 080913B: Fermi GBM detection
  20. GRB 080916C: Swift XRT refined analysis
  21. GRB 080915B, Swift-BAT refined analysis
  22. GRB 080915B: Swift detection of a burst
  23. GRB 080905C: Fermi GBM detection
  24. GRB 080905B: Watcher optical detection
  25. GRB 080905A: Fermi Gamma-ray Burst Monitor detection
  26. GRB 080830: Fermi Gamma-ray Burst Monitor detection
  27. SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
  28. INTEGRAL ToO observation of SGR0501+4516
  29. GRB 080828: Swift-XRT detection of a possible X-ray afterglow
  30. GRB 080828: SuperAGILE GRB Localization
  31. SGR 0501+4516: Decline in Activity
  32. GRB 080824: Fermi Gamma Ray Burst Monitor detection
  33. INTEGRAL ToO Observation of SGR0501+4516
  34. GRB 080723B: XMM-Newton observation
  35. GRB 080727C: Liverpool Telescope observations
  36. GRB080727C: RTT150 optical observations
  37. GRB 080625: Suzaku WAM observation of the prompt emission
  38. GRB 080702: Swift detection of a short burst
  39. GRB 080701A, VATT optical upper limit
  40. GRB 080701A: Early Super-LOTIS Observations
  41. GRB 080701: Enhanced Swift-XRT position
  42. GRB 080701A, Swift-BAT refined analysis
  43. GRB 080701: Swift-XRT Prompt Analysis
  44. GRB 080623: Suzaku WAM observation of the prompt emission
  45. GRB 080625: Gamma Ray Burst Localization by SuperAGILE
  46. GRB 080623: Swift detection of a burst
  47. GRB080613B: MITSuME upper limits
  48. GRB080613A: Optical upper limits with Okayama MITSuME telescope
  49. GRB 080605: optical observations
  50. VLA detection of INTEGRAL burst GRB 080603A
  51. GRB 080605: TLS RRM Analysis, Plateau/Rebrightening, Red OT
  52. GRB 080605: Swift-UVOT refined analysis
  53. GRB080605: optical observations
  54. GRB 080605: Liverpool Telescope optical afterglow candidate
  55. GRB 080605: Swift/UVOT Position of the Optical Afterglow
  56. GRB 080605: TLS RRM Afterglow
  57. Konus-Wind observation of GRB 080603B
  58. GRB 080604: Early Super-LOTIS Observations
  59. GRB 080603 OA candidate
  60. GRB 080602: Swift detection of a burst
  61. GRB 080523: afterglow confirmation and redshift constraints
  62. Konus-Wind observation of reactivation of SGR 1627-41
  63. Reactivation of SGR 1627-41
  64. GRB 080503: 2nd Epoch Chandra X-ray Observations
  65. Errartum: VLA upper limit on GRB 080507
  66. GRB 080430
  67. GRB 080430: Swift detection of a burst with optical afterglow
  68. GRB960202B - on the association with SN 1996cr
  69. GRB 080426: Enhanced Swift-XRT position
  70. GRB 080426, Swift-BAT refined analysis
  71. GRB 080426: Swift detection of a possibly short burst
  72. GRB 080420A: ROTSE-III Optical Limits on a possible short burst
  73. GRB 080328: Suzaku WAM observation of the prompt emission
  74. GRB 080319B: Continued Gemini-South followup and possible host galaxy
  75. GRB 080303
  76. GRB 080303: Swift detection of a burst with optical afterglow
  77. GRB 080303: REM NIR afterglow candidate
  78. GRB 080229, Swift-BAT refined analysis
  79. GRB 080205: optical observation
  80. GRB 080129: Swift-XRT refined analysis
  81. X-ray transient in NGC 2770: RTT150 optical observations
  82. GRB 080120: a long GRB detected by INTEGRAL
  83. Refined Swift UVOT Analysis of SN 2008D (Transient in NGC 2770)
  84. GRB 071227: Magellan observations
  85. Swift-BAT trigger 298308 is not a GRB
  86. GRB 071208?: Swift detection of a possible burst
  87. IPN triangulation of very bright GRB 071125
  88. GRB071104: NIR Afterglow Candidate at TNG
  89. GRB 071117: Swift-XRT revised position
  90. GRB 071112C: Optical and NIR data observed with KANATA
  91. Correction to the Swift-BAT Transient Identification (trigger=296683)
  92. GRB 071112C: Swift XRT refined analysis
  93. GRB 071112C: Optical observations at Crni Vrh
  94. GRB 071112C: Palomar Pre-Imaging
  95. GRB 071112C: Optical and NIR afterglows observed with KANATA
  96. GRB 071112C: Swift detection of a burst with an optical counterpart
  97. VLA IInd observation of INTEGRAL burst GRB 071109
  98. GRB0711101: Two new source from Xinglong TNT observation
  99. GRB 071101: Swift detection of a burst
  100. GRB 071028B Swift-BAT detection of a burst

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