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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"

32500 results found.

  1. GRB 070809: Swift/UVOT Corrected Photometry
  2. Swift Trigger 287421: False trigger due to star tracker loss
  3. GRB 070810A: Swift-BAT refined analysis
  4. GRB 070810B: Xinglong TNT optical Upper Limit
  5. GRB070810B: Optical observations with KANATA
  6. GRB 070809: Swift/UVOT Upper Limits
  7. VLA upper limit on the short hard burst GRB 070729
  8. GRB 070810: Keck redshift and photometry
  9. No radio detection in superAGILE burst 070724B
  10. GRB 070809: Keck Imaging
  11. GRB 070810: Swift-XRT Team Refined Analysis
  12. GRB 070809: Swift-XRT refined analysis
  13. GRB 070810: Swift/UVOT Optical Counterpart
  14. GRB 070809, Swift-BAT refined analysis
  15. GRB 070809: Optical Pre-imaging from Palomar
  16. GRB 070808: Swift/UVOT upper limits
  17. GRB 070809: ROTSE-III Optical Limits
  18. GRB 070808 : Faulkes Telescope South Observations
  19. GCN Swift XRT update position notices and enhanced position circulars
  20. GRB 070808: Swift XRT refined analysis
  21. GRB 070808, Swift-BAT refined analysis
  22. GRB 070808: OPTIMA-Burst optical upper limit
  23. GRB 070808: Xinglong TNT optical Upper Limit
  24. GRB070808: Optical observations with KANATA
  25. GRB 070808: ROTSE-III Optical Limits
  26. GRB061121A: PROMPT Observations
  27. GRB070805 XRT and UVOT afterglow candidate
  28. GRB070612A: Radio upper limit from GMRT
  29. GRB 070721B: correct afterglow position
  30. Swift/UVOT observations of GRB070805
  31. GRB 070805, Swift-BAT refined analysis
  32. GRB 070805: Swift XRT initial analysis.
  33. UVOT observations of SAXJ1810.8-2609
  34. VLA non-detection of GRB 070721B
  35. GRB 070802: REM optical observations
  36. GRB 070724B: Swift-XRT afterglow confirmation
  37. GRB 070802: Swift-XRT refined analysis
  38. GRB070802: Swift/UVOT upper limits
  39. GRB 070802: Confirmation of the optical afterglow
  40. GRB 070802, Swift-BAT refined analysis
  41. GRB 070802: VLT redshift
  42. GRB 070802: refined Swift XRT position
  43. GRB 070802: V-band detection of the candidate afterglow
  44. GRB 070802: LCO I-band candidate
  45. GRB 070802: GROND J band candidate
  46. GRB 070802: LCO optical observations
  47. GRB 070802: Swift detection of a burst
  48. Konus-A observation of GRB 070729
  49. Swift/UVOT detection of GRB070714B
  50. AGILE-ACS position for the SGR 1806-20 July 27 burst
  51. GRB 070729: LCO optical imaging
  52. VLA upper limit on short hard burst GRB 070714B
  53. Intense burst from SGR 1806-20 detected on July 27
  54. GRB070729: Swift/UVOT upper limits
  55. GRB 070729: Swift-XRT refined analysis
  56. GRB 070729, Swift-BAT refined analysis
  57. GRB 070729: Magellan NIR Observations
  58. GRB 070724B: P60 Observations
  59. GRB 070724B: Swift/UVOT Upper limits
  60. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  61. GRB 070724B: Swift-XRT afterglow likely candidate
  62. GRB 070721A: optical observations
  63. GRB 070724A: further VLT observations
  64. GRB 070724B: Suzaku WAM observation of the prompt emission
  65. Konus-Wind observation of GRB 070724B
  66. GRB 070724B: Analysis of AGILE gamma-ray data
  67. GRB 070724B: Swift-XRT afterglow candidates
  68. Four radio sources in Swift-XRT error box of GRB 070724
  69. GRB 070724: optical observations
  70. GRB070724: Host galaxy redshift
  71. GRB 070724: P60 and Gemini Observations
  72. GRB 060814 - Keck host detection and redshift
  73. GRB 070724: Closer association with DSS source
  74. Swift/UVOT refined analysis of GRB070724
  75. GRB 070724: Swift-XRT Team refined analysis
  76. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  77. Short-Hard GRB070714B: PROMPT Observations
  78. GRB 070724, Swift-BAT refined analysis of a short burst
  79. GRB 070721B: further observations and analysis
  80. GRB 070714B: Keck observations
  81. GRB 070721B: optical observations and proposed redshift
  82. Swift/UVOT observations of GRB070721B optical afterglow.
  83. GRB 070721B, Further Swift-BAT refined analysis
  84. Swift/UVOT Observations of GRB070721A
  85. GRB 070721B : Faulkes Telescope South observations
  86. GRB 070721B: Swift-XRT refined analysis
  87. GRB 070721A : Faulkes Telescope South optical limit
  88. GRB 070721A: Swift/XRT refined analysis
  89. GRB 070721B, Swift-BAT refined analysis
  90. GRB 070721A, Swift-BAT refined analysis
  91. GRB070721B: A bright UVOT candidate
  92. GRB 070721B: Swift detection of a burst
  93. GRB 070721: Swift detection of a possible burst
  94. GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
  95. GRB 070714B : Suzaku WAM observation of the prompt emission
  96. GRB070714B: TNG NIR observations
  97. Erratum : Suzaku WAM observation of GRB 070704
  98. GRB 070714A: Swift/UVOT Upper limits
  99. GRB 070714B: Swift/UVOT Upper Limits
  100. GRB 070616: No Evidence for I Band Afterglow

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