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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"

27772 results found.

  1. GRB 071101: BOOTES-2 prompt optical observations
  2. GRB 071101: a nearby galaxy
  3. GRB 071101: Swift detection of a burst
  4. GRB 071031, Swift-BAT refined analysis
  5. GRB 071031: Swift/UVOT detection of afterglow
  6. GRB 071031: Swift-XRT Team refined analysis
  7. GRB 071031: VLT high-resolution spectroscopy
  8. GRB 071031: GROND detection in all bands
  9. GRB 071031: Swift detection of a burst with an optical counterpart
  10. GRB 071028B Swift-BAT detection of a burst
  11. GRB 071028: SARA observations of variable source
  12. Swift UVOT upper limits to GRB071028
  13. GRB 071028: Swift-XRT Team refined analysis
  14. GRB 071028, Swift-BAT refined analysis
  15. GRB 071028: Swift detection of a burst
  16. GRB 071025: Kuiper Telescope Optical Observations
  17. GRB 071018: Revised BAT position
  18. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  19. GRB071021: MARGE Optical Limits
  20. GRB071020, optical upper limit
  21. GRB 071025 Milagro GeV/TeV Observations
  22. Swift UVOT upper limits
  23. GRB 071025: Swift-XRT Team refined analysis
  24. GRB 071025, Swift-BAT refined analysis
  25. GRB 071025: Early Super-LOTIS Observations
  26. GRB 071025: R/I-band update
  27. GRB 071025: ROTSE-III Refined Analysis
  28. GRB 071025: I-detection, R-dropout?
  29. GRB 071025: Swift XRT refined position
  30. GRB 071025: ROTSE-III Detection of Optical Counterpart
  31. GRB 071025: Swift detection of a burst
  32. GRB 071021: R-band detection and analysis
  33. GRB 071020: BTA spectroscopy
  34. GRB071021: Optical+NIR observations
  35. Possible radio detection of GRB 071021 with the VLA
  36. Optical observations of GRB 071020
  37. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  38. Radio detection of GRB 071020 with the VLA
  39. GRB 071021: Magellan i-band observation
  40. GRB 071021: Z-band detection
  41. GRB 071010B: Fading quickly
  42. GRB 071021: optical and NIR observations
  43. GRB 071021: possible high-z burst
  44. GRB 071021, Swift-BAT refined analysis
  45. GRB 071021: Swift-XRT Team refined analysis
  46. Konus-Wind observation of GRB 071020
  47. GRB 071021: Swift detection of a burst
  48. GRB 071020: Swift-XRT refined analysis
  49. GRB 071020, Swift-BAT refined analysis
  50. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  51. GRB071020 - SDSS Pre-burst Observations
  52. GRB 071020: Swift detection of a bright burst
  53. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  54. GRB 071018: Mercator Telescope optical observations
  55. Swift autonomous slewing re-enabled
  56. GRB 071018: Swift-XRT observation
  57. GRB 071017 - Swift XRT observations
  58. VLA radio observation of GRB 071018
  59. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  60. GRB 071018, Swift-BAT refined analysis
  61. GRB 071018?: Swift detection of a possible burst
  62. GRB 071010B: Suzaku WAM observation of the prompt emission
  63. GRB 071013: 3rd TLS Epoch - constraints on variability
  64. GRB 071010B: Keck/DEIMOS emission-line redshift
  65. GRB 071013: TLS Upper Limit
  66. VLA detection of radio afterglow of GRB 071010B
  67. VLA non-detection of GRB 071011
  68. GRB 071013: Optical observations
  69. GRB 071013, Swift-BAT refined analysis
  70. GRB 071013: Swift detection of a burst
  71. GRB 071010C Swift-BAT detection of a burst
  72. GRB 071011: Swift-XRT refined analysis
  73. VLA non-detection of GRB 071010A
  74. GRB 071011, Optical afterglow
  75. GRB 071010B: Optical Detection
  76. GRB 071011: MARGE Optical Limits
  77. GRB 071011: XRT afterglow detection
  78. GRB 071011, Swift-BAT refined analysis
  79. GRB 071011: Early Super-LOTIS Observations
  80. GRB 071010B: Bright OT confirmed with TLS
  81. GRB 071011: Swift detection of a burst
  82. Optical Observation: GRB 071010
  83. Optical observations: GRB 071010A
  84. Konus-Wind observation of GRB 071010B
  85. GRB071010B: Swift/XRT detection
  86. GRB 071010B, Swift-BAT refined analysis
  87. GRB 071006, Swift-BAT refined analysis
  88. GRB 071010B possible optical transient
  89. GRB 071010B: Swift detection of a burst
  90. GRB 071010: Swift-XRT observation
  91. GRB 071008, Swift-BAT refined analysis
  92. GRB 071010, Swift-BAT refined analysis
  93. GRB071008: Swift-XRT observation
  94. GRB 071010: Keck Observations of the Afterglow
  95. GRB 071010: TAROT La Silla observatory detection of the afterglow
  96. GRB 071010: Swift detection of a burst
  97. GRB 071006 Swift-BAT detection of a burst
  98. GRB071008: IAC80 observation
  99. GRB 071008: Swift detection of a burst
  100. GRB 071003: XRT refined analysis

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