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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"

19225 results found.

  1. GRB 080129: TAROT La Silla observatory optical observations
  2. GRB 080129: GROND detection in all bands, and fading
  3. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  4. GRB 080129: Enhanced Swift-XRT position
  5. GRB 080129: Gemini-South Imaging Observations
  6. GRB 080129 (?): UVOT Upper Limits
  7. GRB 080121: Upper limit on X-ray afterglow
  8. GRB 080123 : Suzaku WAM observation of the prompt emission
  9. Konus-Wind observation of GRB 080122
  10. GRB 080122 : Suzaku WAM observation of the prompt emission
  11. GRB 080121: Swift/UVOT upper limits
  12. SNe 2008D and 2007uy: Chandra Detections
  13. GRB 080121: Enhanced Swift-XRT position
  14. IPN triangulation of GRB080122
  15. GRB 080121: Nearby SDSS galaxies
  16. GRB 080123: Swift-XRT refined analysis
  17. GRB 080123: Swift/UVOT refined analysis
  18. GRB 080123: Enhanced Swift-XRT position
  19. GRB 080123: Swift detection of a short burst
  20. GRB 080120: GROND confirmation of the optical afterglow
  21. VLA radio upper limit on GRB 080120
  22. GRB080120: Swift XRT position
  23. Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
  24. XRF 080109 / SN 2008D: UKIRT JHK imaging
  25. optical observations, XRT in NGC 2770
  26. XRF 080109/SN 2008D: PROMPT Optical Imaging
  27. Gemini-South observations of XRF 080109 / SN 2008D
  28. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  29. Discovery of Radio Emission from Transient in NGC 2770
  30. XRF 080109 in NGC2770: NIR observations at TNG
  31. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  32. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
  33. XRF 080109 in NGC2770: Detectable Superluminal Motion
  34. Refined Swift-XRT analysis of the transient in NGC 2770
  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. GRB 071227: Swift-XRT refined analysis
  40. GRB 071227: VLT probable redshift of the candidate host galaxy
  41. GRB071227: Swift/UVOT refined analysis
  42. GRB 071227: REM NIR and Optical observations
  43. GRB 071227: Swift detection of a burst
  44. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  45. GRB 071125: Suzaku WAM observation of the prompt emission
  46. GRB 070429B: Probable host galaxy and redshift
  47. GRB 071129, Swift-BAT refined analysis
  48. GRB 071129: Swift detection of a burst
  49. Konus-Wind and Konus-A observations of GRB 071125
  50. IPN triangulation of very bright GRB 071125
  51. GRB 071126: Enhanced Swift-XRT position
  52. GRB071122: Swift/UVOT Observations
  53. GRB071104: NIR Afterglow Candidate at TNG
  54. GRB 071122, Swift-BAT refined analysis
  55. GRB 071122 Swift-XRT refined analysis
  56. GRB 071122: P60 Optical Afterglow Candidate
  57. GRB 071122: ROTSE-III Optical Limits
  58. GRB 071122: Swift detection of a burst
  59. GRB 071118: P60 Observations
  60. GRB071118 MITSuME OAO optical observation
  61. GRB 071118: Observations from OSN
  62. GRB 071117: VLT observations and probable redshift
  63. Swift/UVOT observations of GRB071118
  64. Konus-Wind and Konus-A observations of GRB 071117
  65. Swift XRT follow-up observations of GRB071008
  66. Swift/UVOT upper limits for GRB 071117
  67. GRB071118: Swift XRT refined analysis
  68. GRB 071117: Gemini Optical Afterglow Discovery
  69. GRB 071117: TAROT La Silla observatory optical observations
  70. GRB 071118: Swift detection of a burst
  71. GRB 071117: Gemini Observations
  72. VLT FORS2 observations of short hard GRB071112B
  73. GRB 071117: Swift detection of a bright burst
  74. Swift detection of MXB 0656-072
  75. ATCA radio observations of short hard burst GRB 071112B
  76. GRB 071112C: Optical and NIR data observed with KANATA
  77. GRB 071112C MITSuME Akeno early optical observation
  78. GRB 071112C: SARA upper limit
  79. GRB 071112C : Second Epoch Lulin R-band observations
  80. GRB071112C MITSuME Okayama Optical Observation
  81. GRB 071112C: Swift-BAT refined analysis
  82. GRB 071112C: Swift XRT refined analysis
  83. Swift UVOT upper limits of GRB071112B
  84. GRB 071112B: Gemini Optical Imaging
  85. GRB 071112B: Swift-XRT preliminary analysis
  86. GRB 071112C : Lulin R-band observation
  87. GRB 071112C: TAROT Calern observatory optical observations
  88. Swift XRT follow-up observations of GRB071028B
  89. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  90. GRB 071112C: Optical and NIR afterglows observed with KANATA
  91. GRB 071112B: ROTSE-III Rapid Optical Limits
  92. GRB 071112C: Swift detection of a burst with an optical counterpart
  93. GRB 071112: Swift detection of a possible burst
  94. Swift/UVOT initial analysis of GRB071109
  95. GRB 071109: further Swift-XRT analysis
  96. GRB 071109: TAROT Calern observatory optical observations
  97. GRB 071109: Swift-XRT possible X-ray counterpart
  98. GRB 071104: Possible Swift UVOT Afterglow Candidate
  99. GRB 071104: Swift-XRT position
  100. Swift XRT and UVOT observations of GRB071028B

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