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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"

26175 results found.

  1. Konus-Wind observation of GRB 080122
  2. GRB 080122 : Suzaku WAM observation of the prompt emission
  3. GRB 080121: Swift/UVOT upper limits
  4. SNe 2008D and 2007uy: Chandra Detections
  5. GRB 080121: Enhanced Swift-XRT position
  6. Transient 080109/SN 2008D: Spectroscopic Evolution and Re-Classification
  7. IPN triangulation of GRB080122
  8. GRB 080121: Nearby SDSS galaxies
  9. GRB 080123: Swift-XRT refined analysis
  10. GRB 080123: Swift/UVOT refined analysis
  11. GRB 080123, Swift-BAT refined analysis
  12. GRB 080123: Enhanced Swift-XRT position
  13. GRB 080123: Swift detection of a short burst
  14. GRB 080120: GROND confirmation of the optical afterglow
  15. VLA radio upper limit on GRB 080120
  16. GRB 080120: Swift-XRT refined analysis
  17. GRB 080120: GROND detection
  18. GRB080120: Swift XRT position
  19. GRB 080120: a long GRB detected by INTEGRAL
  20. Transient in NGC2770 / SN2008D: Metallicity of nearby HII regions
  21. Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
  22. XRF 080109 / SN 2008D: UKIRT JHK imaging
  23. optical observations, XRT in NGC 2770
  24. XRF 080109/SN 2008D: PROMPT Optical Imaging
  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. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  34. GRB 071227: Suzaku WAM observation of the prompt emission
  35. GRB 071227: optical afterglow
  36. Further Swift-BAT analysis of GRB 071227
  37. Konus-Wind observation of GRB 071227
  38. GRB 071227: Swift-XRT refined analysis
  39. GRB 071227: VLT probable redshift of the candidate host galaxy
  40. GRB071227: Swift/UVOT refined analysis
  41. GRB 071227: REM NIR and Optical observations
  42. Swift-BAT refined analysis of short GRB 071227
  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 071126: Enhanced Swift-XRT position
  49. GRB071122: Swift/UVOT Observations
  50. GRB071104: NIR Afterglow Candidate at TNG
  51. GRB 071122, Swift-BAT refined analysis
  52. GRB 071122 Swift-XRT refined analysis
  53. GRB 071122: P60 Optical Afterglow Candidate
  54. GRB 071122: Swift detection of a burst
  55. GRB 071118: P60 Observations
  56. GRB071118 MITSuME OAO optical observation
  57. GRB 071118: Observations from OSN
  58. GRB 071117: VLT observations and probable redshift
  59. Swift/UVOT observations of GRB071118
  60. Konus-Wind and Konus-A observations of GRB 071117
  61. Swift XRT follow-up observations of GRB071008
  62. Swift/UVOT upper limits for GRB 071117
  63. GRB071118: Swift XRT refined analysis
  64. GRB 071117: Gemini Optical Afterglow Discovery
  65. GRB 071118, Swift-BAT refined analysis
  66. GRB 071117: TAROT La Silla observatory optical observations
  67. GRB 071118: Swift detection of a burst
  68. GRB 071117: Gemini Observations
  69. GRB 071117: Swift-XRT refined analysis
  70. GRB 071117, Swift-BAT refined analysis
  71. Swift detection of MXB 0656-072
  72. GRB 071112C: Optical and NIR data observed with KANATA
  73. GRB 071112C MITSuME Akeno early optical observation
  74. GRB 071112C: SARA upper limit
  75. GRB 071112C : Second Epoch Lulin R-band observations
  76. GRB071112C MITSuME Okayama Optical Observation
  77. GRB 071112C: Swift-BAT refined analysis
  78. GRB 071112C: Swift XRT refined analysis
  79. Swift UVOT upper limits of GRB071112B
  80. GRB 071112B: Gemini Optical Imaging
  81. GRB 071112B: Swift-XRT preliminary analysis
  82. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  83. GRB 071112C : Lulin R-band observation
  84. GRB 071112C: TAROT Calern observatory optical observations
  85. Swift XRT follow-up observations of GRB071028B
  86. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  87. GRB 071112C: Optical and NIR afterglows observed with KANATA
  88. GRB 071112C: Swift detection of a burst with an optical counterpart
  89. GRB 071112B: Swift detection of a short hard burst
  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: IBIS refined analysis
  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. Swift XRT and UVOT observations of GRB071028B

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