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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"

28051 results found.

  1. Gemini-South observations of XRF 080109 / SN 2008D
  2. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  3. Discovery of Radio Emission from Transient in NGC 2770
  4. XRF 080109 in NGC2770: NIR observations at TNG
  5. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  6. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
  7. XRF 080109 in NGC2770: Detectable Superluminal Motion
  8. Refined Swift-XRT analysis of the transient in NGC 2770
  9. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  10. GRB 071227: Suzaku WAM observation of the prompt emission
  11. GRB 071227: optical afterglow
  12. Further Swift-BAT analysis of GRB 071227
  13. Konus-Wind observation of GRB 071227
  14. GRB 071227: Swift-XRT refined analysis
  15. GRB 071227: VLT probable redshift of the candidate host galaxy
  16. GRB071227: Swift/UVOT refined analysis
  17. GRB 071227: REM NIR and Optical observations
  18. Swift-BAT refined analysis of short GRB 071227
  19. GRB 071227: Swift detection of a burst
  20. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  21. GRB 071125: Suzaku WAM observation of the prompt emission
  22. GRB 070429B: Probable host galaxy and redshift
  23. GRB 071129, Swift-BAT refined analysis
  24. GRB 071126: Enhanced Swift-XRT position
  25. GRB071122: Swift/UVOT Observations
  26. GRB071104: NIR Afterglow Candidate at TNG
  27. GRB 071122, Swift-BAT refined analysis
  28. GRB 071122 Swift-XRT refined analysis
  29. GRB 071122: P60 Optical Afterglow Candidate
  30. GRB 071122: Swift detection of a burst
  31. GRB 071118: P60 Observations
  32. GRB071118 MITSuME OAO optical observation
  33. GRB 071118: Observations from OSN
  34. GRB 071117: VLT observations and probable redshift
  35. Swift/UVOT observations of GRB071118
  36. Konus-Wind and Konus-A observations of GRB 071117
  37. Swift XRT follow-up observations of GRB071008
  38. Swift/UVOT upper limits for GRB 071117
  39. GRB071118: Swift XRT refined analysis
  40. GRB 071117: Gemini Optical Afterglow Discovery
  41. GRB 071118, Swift-BAT refined analysis
  42. GRB 071117: TAROT La Silla observatory optical observations
  43. GRB 071118: Swift detection of a burst
  44. GRB 071117: Gemini Observations
  45. GRB 071117: Swift-XRT refined analysis
  46. GRB 071117, Swift-BAT refined analysis
  47. Swift detection of MXB 0656-072
  48. GRB 071112C: Optical and NIR data observed with KANATA
  49. GRB 071112C MITSuME Akeno early optical observation
  50. GRB 071112C: SARA upper limit
  51. GRB 071112C : Second Epoch Lulin R-band observations
  52. GRB071112C MITSuME Okayama Optical Observation
  53. GRB 071112C: Swift-BAT refined analysis
  54. GRB 071112C: Swift XRT refined analysis
  55. Swift UVOT upper limits of GRB071112B
  56. GRB 071112B: Gemini Optical Imaging
  57. GRB 071112B: Swift-XRT preliminary analysis
  58. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  59. GRB 071112C : Lulin R-band observation
  60. GRB 071112C: TAROT Calern observatory optical observations
  61. Swift XRT follow-up observations of GRB071028B
  62. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  63. GRB 071112C: Optical and NIR afterglows observed with KANATA
  64. GRB 071112C: Swift detection of a burst with an optical counterpart
  65. GRB 071112B: Swift detection of a short hard burst
  66. GRB 071112: Swift detection of a possible burst
  67. Swift/UVOT initial analysis of GRB071109
  68. GRB 071109: further Swift-XRT analysis
  69. GRB 071109: TAROT Calern observatory optical observations
  70. GRB 071109: Swift-XRT possible X-ray counterpart
  71. GRB 071109: IBIS refined analysis
  72. GRB 071104: Swift-XRT Team Refined Analysis
  73. GRB 071104: Possible Swift UVOT Afterglow Candidate
  74. GRB 071104: Swift-XRT position
  75. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  76. Swift XRT and UVOT observations of GRB071028B
  77. GRB 071101, Swift-BAT refined analysis
  78. GRB 071101: Swift-XRT Team refined analysis
  79. GRB071101: Optical and NIR upper limits by KANATA
  80. GRB0711101: Two new source from Xinglong TNT observation
  81. GRB 071101: TAROT Calern observatory optical observations
  82. GRB071101 LOAO B,V,R,I observation
  83. GRB 071101: Swift detection of a burst
  84. GRB 071031, Swift-BAT refined analysis
  85. GRB 071031: Swift-XRT Team refined analysis
  86. GRB 071020: MITSuME Akeno optical observations
  87. GRB 071031: REM NIR and Optical observation
  88. GRB 071031: Swift detection of a burst with an optical counterpart
  89. GRB 071028B Swift-BAT detection of a burst
  90. GRB 071028: SARA observations of variable source
  91. Swift UVOT upper limits to GRB071028
  92. GRB071028: Xinglong EST V-band upper limit
  93. GRB 071028: Swift-XRT Team refined analysis
  94. GRB 071028, Swift-BAT refined analysis
  95. GRB 071028: Swift detection of a burst
  96. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  97. GRB071021: MARGE Optical Limits
  98. GRB071020, optical upper limit
  99. GRB 071025: SARA VRI upper limits
  100. Swift UVOT upper limits

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