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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"

26167 results found.

  1. GRB 080123: Swift-XRT refined analysis
  2. GRB 080123: Swift/UVOT refined analysis
  3. GRB 080123, Swift-BAT refined analysis
  4. GRB 080123: Enhanced Swift-XRT position
  5. GRB 080123: Swift detection of a short burst
  6. GRB 080120: GROND confirmation of the optical afterglow
  7. VLA radio upper limit on GRB 080120
  8. GRB 080120: Swift-XRT refined analysis
  9. GRB 080120: GROND detection
  10. GRB080120: Swift XRT position
  11. GRB 080120: a long GRB detected by INTEGRAL
  12. Transient in NGC2770 / SN2008D: Metallicity of nearby HII regions
  13. Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
  14. XRF 080109 / SN 2008D: UKIRT JHK imaging
  15. optical observations, XRT in NGC 2770
  16. XRF 080109/SN 2008D: PROMPT Optical Imaging
  17. Gemini-South observations of XRF 080109 / SN 2008D
  18. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  19. Discovery of Radio Emission from Transient in NGC 2770
  20. XRF 080109 in NGC2770: NIR observations at TNG
  21. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  22. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
  23. XRF 080109 in NGC2770: Detectable Superluminal Motion
  24. Refined Swift-XRT analysis of the transient in NGC 2770
  25. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  26. GRB 071227: Suzaku WAM observation of the prompt emission
  27. GRB 071227: optical afterglow
  28. Further Swift-BAT analysis of GRB 071227
  29. Konus-Wind observation of GRB 071227
  30. GRB 071227: Swift-XRT refined analysis
  31. GRB 071227: VLT probable redshift of the candidate host galaxy
  32. GRB071227: Swift/UVOT refined analysis
  33. GRB 071227: REM NIR and Optical observations
  34. Swift-BAT refined analysis of short GRB 071227
  35. GRB 071227: Swift detection of a burst
  36. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  37. GRB 071125: Suzaku WAM observation of the prompt emission
  38. GRB 070429B: Probable host galaxy and redshift
  39. GRB 071129, Swift-BAT refined analysis
  40. GRB 071126: Enhanced Swift-XRT position
  41. GRB071122: Swift/UVOT Observations
  42. GRB071104: NIR Afterglow Candidate at TNG
  43. GRB 071122, Swift-BAT refined analysis
  44. GRB 071122 Swift-XRT refined analysis
  45. GRB 071122: P60 Optical Afterglow Candidate
  46. GRB 071122: Swift detection of a burst
  47. GRB 071118: P60 Observations
  48. GRB071118 MITSuME OAO optical observation
  49. GRB 071118: Observations from OSN
  50. GRB 071117: VLT observations and probable redshift
  51. Swift/UVOT observations of GRB071118
  52. Konus-Wind and Konus-A observations of GRB 071117
  53. Swift XRT follow-up observations of GRB071008
  54. Swift/UVOT upper limits for GRB 071117
  55. GRB071118: Swift XRT refined analysis
  56. GRB 071117: Gemini Optical Afterglow Discovery
  57. GRB 071118, Swift-BAT refined analysis
  58. GRB 071117: TAROT La Silla observatory optical observations
  59. GRB 071118: Swift detection of a burst
  60. GRB 071117: Gemini Observations
  61. GRB 071117: Swift-XRT refined analysis
  62. GRB 071117, Swift-BAT refined analysis
  63. Swift detection of MXB 0656-072
  64. GRB 071112C: Optical and NIR data observed with KANATA
  65. GRB 071112C MITSuME Akeno early optical observation
  66. GRB 071112C: SARA upper limit
  67. GRB 071112C : Second Epoch Lulin R-band observations
  68. GRB071112C MITSuME Okayama Optical Observation
  69. GRB 071112C: Swift-BAT refined analysis
  70. GRB 071112C: Swift XRT refined analysis
  71. Swift UVOT upper limits of GRB071112B
  72. GRB 071112B: Gemini Optical Imaging
  73. GRB 071112B: Swift-XRT preliminary analysis
  74. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  75. GRB 071112C : Lulin R-band observation
  76. GRB 071112C: TAROT Calern observatory optical observations
  77. Swift XRT follow-up observations of GRB071028B
  78. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  79. GRB 071112C: Optical and NIR afterglows observed with KANATA
  80. GRB 071112C: Swift detection of a burst with an optical counterpart
  81. GRB 071112B: Swift detection of a short hard burst
  82. GRB 071112: Swift detection of a possible burst
  83. Swift/UVOT initial analysis of GRB071109
  84. GRB 071109: further Swift-XRT analysis
  85. GRB 071109: TAROT Calern observatory optical observations
  86. GRB 071109: Swift-XRT possible X-ray counterpart
  87. GRB 071109: IBIS refined analysis
  88. GRB 071104: Swift-XRT Team Refined Analysis
  89. GRB 071104: Possible Swift UVOT Afterglow Candidate
  90. GRB 071104: Swift-XRT position
  91. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  92. Swift XRT and UVOT observations of GRB071028B
  93. GRB 071101, Swift-BAT refined analysis
  94. GRB 071101: Swift-XRT Team refined analysis
  95. GRB071101: Optical and NIR upper limits by KANATA
  96. GRB0711101: Two new source from Xinglong TNT observation
  97. GRB 071101: TAROT Calern observatory optical observations
  98. GRB071101 LOAO B,V,R,I observation
  99. GRB 071101: Swift detection of a burst
  100. GRB 071031, Swift-BAT refined analysis

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