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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"

26496 results found.

  1. A new website of high-level data products for Swift GRBs
  2. GRB 080121: Upper limit on X-ray afterglow
  3. GRB 080123 : Suzaku WAM observation of the prompt emission
  4. Konus-Wind observation of GRB 080122
  5. GRB 080122 : Suzaku WAM observation of the prompt emission
  6. GRB 080121: Swift/UVOT upper limits
  7. SNe 2008D and 2007uy: Chandra Detections
  8. GRB 080121: Enhanced Swift-XRT position
  9. Transient 080109/SN 2008D: Spectroscopic Evolution and Re-Classification
  10. IPN triangulation of GRB080122
  11. GRB 080121: Nearby SDSS galaxies
  12. GRB 080121: Swift-BAT detection of a very weak, short burst
  13. GRB 080123: Swift-XRT refined analysis
  14. GRB 080123: Swift/UVOT refined analysis
  15. GRB 080123: Enhanced Swift-XRT position
  16. GRB 080123: Swift detection of a short burst
  17. GRB 080120: GROND confirmation of the optical afterglow
  18. VLA radio upper limit on GRB 080120
  19. GRB 080120: Swift-XRT refined analysis
  20. GRB080120: Swift XRT position
  21. GRB 080120: a long GRB detected by INTEGRAL
  22. Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
  23. XRF 080109 / SN 2008D: UKIRT JHK imaging
  24. optical observations, XRT in NGC 2770
  25. Gemini-South observations of XRF 080109 / SN 2008D
  26. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  27. Discovery of Radio Emission from Transient in NGC 2770
  28. XRF 080109 in NGC2770: NIR observations at TNG
  29. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  30. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
  31. XRF 080109 in NGC2770: Detectable Superluminal Motion
  32. Refined Swift-XRT analysis of the transient in NGC 2770
  33. Early OT detection of XRF in NGC 2770 in Asiago frames
  34. Bright X-ray Transient (a XRF? ) in NGC 2770 - A SN optical counterpart?
  35. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  36. GRB 071227: Suzaku WAM observation of the prompt emission
  37. GRB 071227: optical afterglow
  38. Further Swift-BAT analysis of GRB 071227
  39. Konus-Wind observation of GRB 071227
  40. GRB 071227: Magellan redshift confirmation
  41. GRB 071227: Swift-XRT refined analysis
  42. GRB 071227: VLT probable redshift of the candidate host galaxy
  43. GRB071227: Swift/UVOT refined analysis
  44. GRB 071227: REM NIR and Optical observations
  45. Swift-BAT refined analysis of short GRB 071227
  46. GRB 071227: Swift detection of a burst
  47. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  48. GRB 071125: Suzaku WAM observation of the prompt emission
  49. GRB 070429B: Probable host galaxy and redshift
  50. GRB 071129, Swift-BAT refined analysis
  51. GRB 071126: Enhanced Swift-XRT position
  52. GRB071122: Swift/UVOT Observations
  53. GRB071104: NIR Afterglow Candidate at TNG
  54. GRB 071122 Swift-XRT refined analysis
  55. GRB 071122: P60 Optical Afterglow Candidate
  56. GRB 071122: Swift detection of a burst
  57. GRB 071118: P60 Observations
  58. GRB071118 MITSuME OAO optical observation
  59. GRB 071118: Observations from OSN
  60. GRB 071117: VLT observations and probable redshift
  61. Swift/UVOT observations of GRB071118
  62. Konus-Wind and Konus-A observations of GRB 071117
  63. Swift XRT follow-up observations of GRB071008
  64. Swift/UVOT upper limits for GRB 071117
  65. GRB071118: Swift XRT refined analysis
  66. GRB 071117: Gemini Optical Afterglow Discovery
  67. GRB 071118, Swift-BAT refined analysis
  68. GRB 071117: TAROT La Silla observatory optical observations
  69. GRB 071118: Swift detection of a burst
  70. GRB 071117: Gemini Observations
  71. GRB 071117: Swift-XRT refined analysis
  72. Swift detection of MXB 0656-072
  73. GRB 071112C: Optical and NIR data observed with KANATA
  74. GRB 071112C MITSuME Akeno early optical observation
  75. GRB 071112C: SARA upper limit
  76. GRB 071112C : Second Epoch Lulin R-band observations
  77. GRB071112C MITSuME Okayama Optical Observation
  78. GRB 071112C: Swift-BAT refined analysis
  79. GRB 071112C: Swift XRT refined analysis
  80. Swift UVOT upper limits of GRB071112B
  81. GRB 071112C: VLT redshift
  82. GRB 071112B: Gemini Optical Imaging
  83. GRB 071112B: Swift-XRT preliminary analysis
  84. GRB 071112C : Lulin R-band observation
  85. GRB 071112C: TAROT Calern observatory optical observations
  86. Swift XRT follow-up observations of GRB071028B
  87. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  88. GRB 071112C: Optical and NIR afterglows observed with KANATA
  89. GRB 071112C: Swift detection of a burst with an optical counterpart
  90. GRB 071112: Swift detection of a possible burst
  91. Swift/UVOT initial analysis of GRB071109
  92. GRB 071109: further Swift-XRT analysis
  93. GRB 071109: TAROT Calern observatory optical observations
  94. GRB 071109: Swift-XRT possible X-ray counterpart
  95. GRB 071109: BOOTES-2 prompt optical observations
  96. GRB 071104: Swift-XRT Team Refined Analysis
  97. GRB 071104: Possible Swift UVOT Afterglow Candidate
  98. GRB 071104: Swift-XRT position
  99. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  100. GRB071010b: optical observation

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