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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"

36784 results found.

  1. GRB 070805: Swift XRT initial analysis.
  2. GRB 070805: Swift/UVOT initial analysis
  3. GRB 070805: Swift detection of a burst
  4. VLA non-detection of GRB 070721B
  5. GRB 070802: REM optical observations
  6. GRB 070724B: Swift-XRT afterglow confirmation
  7. GRB 070802: Swift-XRT refined analysis
  8. GRB 070802: Confirmation of the optical afterglow
  9. GRB 070802, Swift-BAT refined analysis
  10. GRB 070802: VLT redshift
  11. GRB 070802: refined Swift XRT position
  12. GRB 070802: V-band detection of the candidate afterglow
  13. GRB 070802: LCO I-band candidate
  14. GRB 070802: GROND J band candidate
  15. GRB 070802: LCO optical observations
  16. GRB 070802: Swift detection of a burst
  17. GRB 070731, Swift-BAT refined analysis
  18. Konus-A observation of GRB 070729
  19. Swift/UVOT detection of GRB070714B
  20. GRB 070724B: pseudo-z ~ 1.10 from prompt emission spectrum
  21. GRB 070729: LCO optical imaging
  22. VLA upper limit on short hard burst GRB 070714B
  23. Intense burst from SGR 1806-20 detected on July 27
  24. GRB 070729: Swift-XRT refined analysis
  25. GRB 070729, Swift-BAT refined analysis
  26. GRB 070729: Magellan NIR Observations
  27. GRB 070724B: P60 Observations
  28. GRB 070729: Swift detection of a short hard burst
  29. GRB 070724B: Swift/UVOT Upper limits
  30. GRB 070724B: Swift-XRT afterglow likely candidate
  31. GRB 070721A: optical observations
  32. GRB 070724A: further VLT observations
  33. GRB 070724B: Suzaku WAM observation of the prompt emission
  34. Konus-Wind observation of GRB 070724B
  35. GRB 070724B: Analysis of AGILE gamma-ray data
  36. GRB 070724B: Swift-XRT afterglow candidates
  37. GRB 070724b: First Gamma Ray Burst Localization by SuperAGILE onboard
  38. Four radio sources in Swift-XRT error box of GRB 070724
  39. GRB 070724: optical observations
  40. GRB 070724: P60 and Gemini Observations
  41. GRB 060814 - Keck host detection and redshift
  42. GRB 070724: IR observations
  43. GRB 070724: Closer association with DSS source
  44. GRB 070724: Swift-XRT Team refined analysis
  45. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  46. Short-Hard GRB070714B: PROMPT Observations
  47. GRB 070724, Swift-BAT refined analysis of a short burst
  48. GRB 070721B: further observations and analysis
  49. GRB 070724: Swift detection of a burst
  50. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  51. GRB 070714B: Keck observations
  52. GRB 070721B: optical observations and proposed redshift
  53. GRB 070721B, Further Swift-BAT refined analysis
  54. Swift/UVOT Observations of GRB070721A
  55. GRB 070721B : Faulkes Telescope South observations
  56. GRB 070721B: Swift-XRT refined analysis
  57. GRB 070721A : Faulkes Telescope South optical limit
  58. GRB 070721A: Swift/XRT refined analysis
  59. GRB 070721B, Swift-BAT refined analysis
  60. GRB 070721A, Swift-BAT refined analysis
  61. GRB070721B: A bright UVOT candidate
  62. GRB 070721B: Swift detection of a burst
  63. GRB 070721: Swift detection of a possible burst
  64. GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
  65. GRB 070714B : Suzaku WAM observation of the prompt emission
  66. GRB 070714A: Swift-BAT T_zero
  67. Erratum : Suzaku WAM observation of GRB 070704
  68. GRB 070714A: Swift/UVOT Upper limits
  69. GRB 070714B: Swift/UVOT Upper Limits
  70. GRB 070714B: Swift-BAT spectral lag for the SHB
  71. GRB 070714B: confirmation of optical afterglow
  72. GRB 070616: No Evidence for I Band Afterglow
  73. GRB 070714A: Swift XRT refined analysis
  74. GRB070714B: Swift-XRT refined analysis
  75. GRB 070707: Swift-XRT follow-up observations
  76. GRB 070714b ("Bastille"): Optical Pre-Imaging (Clarification)
  77. GRB 070714 ("Bastille"): Optical Pre-Imaging
  78. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  79. GRB 070714A, Swift-BAT refined analysis
  80. GRB 070714 : Liverpool Telescope optical counterpart ?
  81. GRB 070714: Swift detection of a bright burst, possibly short
  82. Swift detection of a possible burst (Trigger 284850)
  83. SN 2007bg - off-axis GRB?
  84. GRB 070704: RTT150 optical observations
  85. GRB 070704: Suzaku/WAM observation of the prompt emission
  86. Konus-Wind observation of GRB 070707
  87. GRB 070707: optical afterglow
  88. GRB 070707: object inside XRT error circle
  89. Swift XRT observation of GRB 070707
  90. GRB 070707: VLT observations
  91. INTEGRAL GRB 070707 is a short hard burst
  92. INTEGRAL GRB 070707 is a short hard burst
  93. GRB 070707: A long GRB detected by INTEGRAL
  94. GRB 070707: A long GRB detected by INTEGRAL
  95. GRB 070429B: NIR Observations
  96. GRB070704: FAVOR optical observations
  97. GRB 070704 : Liverpool Telescope Observations
  98. GRB 070611: VLT observations
  99. VLA detection of GRB 070612A in C Band
  100. Konus-Wind observation of GRB 070626

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