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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"

37756 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. Swift trigger(=301779) is not a GRB
  5. GRB 080122: pseudo-z= 1.93 from prompt emission spectrum
  6. Konus-Wind observation of GRB 080122
  7. GRB 080122 : Suzaku WAM observation of the prompt emission
  8. GRB 080121: Swift/UVOT upper limits
  9. SNe 2008D and 2007uy: Chandra Detections
  10. GRB 080121 position was incorrect
  11. GRB 080121: Enhanced Swift-XRT position
  12. Two non-burst Swift SubThreshold triggers
  13. IPN triangulation of GRB080122
  14. GRB 080121: Nearby SDSS galaxies
  15. GRB 080121: Swift-BAT detection of a very weak, short burst
  16. GRB 080123: Swift-XRT refined analysis
  17. GRB 080123: Swift/UVOT refined analysis
  18. X-ray transient in NGC 2770: RTT150 optical observations
  19. GRB 080123, Swift-BAT refined analysis
  20. GRB 080123: Enhanced Swift-XRT position
  21. GRB 080123: Swift detection of a short burst
  22. GRB 080120: GROND confirmation of the optical afterglow
  23. VLA radio upper limit on GRB 080120
  24. GRB 080120: Swift-XRT refined analysis
  25. UVOT detection of GRB080120
  26. GRB 080120: GROND detection
  27. GRB 080120 : Planned XMM-Newton observation
  28. GRB080120: Swift XRT position
  29. GRB 080120: a long GRB detected by INTEGRAL
  30. Swift UVOT Monitoring of the SN 2008D Brightening (Transient in NGC 2770)
  31. XRF 080109 / SN 2008D: spectroscopic evolution
  32. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  33. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  34. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
  35. XRF 080109 in NGC2770: Detectable Superluminal Motion
  36. Detailed Spectroscopic ID of SN 2008D (Transient in NGC 2770)
  37. XRF in NGC 2770: Search for X-ray periodicity
  38. Refined Swift-XRT analysis of the transient in NGC 2770
  39. Transient in NGC 2770: spectroscopic evidence for a SN
  40. Refined Swift UVOT Analysis of SN 2008D (Transient in NGC 2770)
  41. Swift UVOT Observations of the X-ray transient in NGC 2770
  42. Early OT detection of XRF in NGC 2770 in Asiago frames
  43. Bright X-ray transient / possible XRF in NGC 2770: TNG R imaging
  44. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  45. GRB 071227: Suzaku WAM observation of the prompt emission
  46. GRB 071227: optical afterglow
  47. Further Swift-BAT analysis of GRB 071227
  48. Konus-Wind observation of GRB 071227
  49. GRB 071227: Magellan redshift confirmation
  50. GRB 071227: Swift-XRT refined analysis
  51. GRB 071227: VLT probable redshift of the candidate host galaxy
  52. GRB 071227: Magellan observations
  53. GRB071227: Swift/UVOT refined analysis
  54. GRB 071227: REM NIR and Optical observations
  55. Swift-BAT refined analysis of short GRB 071227
  56. GRB 071227: Swift detection of a burst
  57. GRB071020: optical observations
  58. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  59. Swift-BAT trigger 298308 is not a GRB
  60. GRB 071208?: Swift detection of a possible burst
  61. IBAS Alert #4772 in not a GRB
  62. GRB 071125: Suzaku WAM observation of the prompt emission
  63. GRB 070429B: Probable host galaxy and redshift
  64. GRB 071129, Swift-BAT refined analysis
  65. GRB 071129: Swift detection of a burst
  66. Konus-Wind and Konus-A observations of GRB 071125
  67. IPN triangulation of very bright GRB 071125
  68. GRB 071112C: Optical/NIR observations
  69. Disregard the "GRB 071126" position
  70. GRB 071126: Enhanced Swift-XRT position
  71. VLA radio detection of GRB 071122
  72. GRB071122: Swift/UVOT Observations
  73. GRB071104: NIR Afterglow Candidate at TNG
  74. GRB 071122: MASTER optical observation
  75. GRB 071122, Swift-BAT refined analysis
  76. GRB 071122 Swift XRT position update sent in error.
  77. GRB 071122 Swift-XRT refined analysis
  78. GRB 071122: Corrected P60 Coordinates
  79. GRB071122: Gemini Absorption redshift
  80. GRB 071122: P60 Optical Afterglow Candidate
  81. GRB 071122: ROTSE-III Optical Limits
  82. GRB 071122: Swift detection of a burst
  83. GRB 071118: P60 Observations
  84. GRB071118 MITSuME OAO optical observation
  85. GRB 071118: Observations from OSN
  86. GRB 071117: VLT observations and probable redshift
  87. Swift/UVOT observations of GRB071118
  88. GRB 071117: Swift-XRT revised position
  89. Konus-Wind and Konus-A observations of GRB 071117
  90. Swift XRT follow-up observations of GRB071008
  91. Swift/UVOT upper limits for GRB 071117
  92. GRB071118: Swift XRT refined analysis
  93. GRB 071117: Gemini Optical Afterglow Discovery
  94. GRB 071118, Swift-BAT refined analysis
  95. GRB 071117: TAROT La Silla observatory optical observations
  96. GRB 071112B: Gemini Image Differencing
  97. GRB 071118: Swift detection of a burst
  98. GRB 071117: Gemini Observations
  99. GRB 071117: Las Campanas optical observations
  100. GRB 071117: Swift-XRT refined analysis

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