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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"

35433 results found.

  1. GRB 071112C: VLT redshift
  2. GRB 071112B: Magellan i-band imaging
  3. GRB 071112B: Gemini Optical Imaging (Correction)
  4. GRB 071112B: Gemini Optical Imaging
  5. GRB 071112B: Swift-XRT preliminary analysis
  6. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  7. GRB071112C: NOT observations
  8. GRB 071112C: Palomar Pre-Imaging
  9. Swift-BAT trigger 296491 is not a GRB
  10. GRB 071112C : Lulin R-band observation
  11. GRB 071112C: RTT150 optical observations
  12. GRB 071112C: TAROT Calern observatory optical observations
  13. Swift XRT follow-up observations of GRB071028B
  14. GRB 071112C: Optical and NIR afterglows observed with KANATA
  15. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  16. GRB 071112B: ROTSE-III Rapid Optical Limits
  17. GRB 071112C: Swift detection of a burst with an optical counterpart
  18. GRB 071112B: Swift detection of a short hard burst
  19. GRB 071112: Swift detection of a possible burst
  20. VLA IInd observation of INTEGRAL burst GRB 071109
  21. Swift/UVOT initial analysis of GRB071109
  22. GRB 071109: further Swift-XRT analysis
  23. GRB 071109: TAROT Calern observatory optical observations
  24. No radio detection at Swift-XRT position
  25. GRB 071109: Swift-XRT possible X-ray counterpart
  26. VLA prompt radio detection of the INTEGRAL burst 071109
  27. GRB 071109: IBIS refined analysis
  28. GRB 071109: BOOTES-2 prompt optical observations
  29. GRB 071109: A long GRB detected by INTEGRAL
  30. GRB 071104: Swift-XRT Team Refined Analysis
  31. GRB 071104: Possible Swift UVOT Afterglow Candidate
  32. GRB 071104: Swift-XRT position
  33. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  34. GRB071010b: optical observation
  35. Swift XRT and UVOT observations of GRB071028B
  36. GRB 071101, Swift-BAT refined analysis
  37. GRB 071101: Swift-XRT Team refined analysis
  38. GRB071101: Optical and NIR upper limits by KANATA
  39. GRB 071101: TAROT Calern observatory optical observations
  40. GRB 071101: Swift XRT position
  41. GRB071101 LOAO B,V,R,I observation
  42. GRB 071101: BOOTES-2 prompt optical observations
  43. GRB 071101: a nearby galaxy
  44. GRB 071101: Swift detection of a burst
  45. GRB 071031, Swift-BAT refined analysis
  46. GRB 071031: Swift/UVOT detection of afterglow
  47. GRB 071031: Swift-XRT Team refined analysis
  48. GRB 071020: MITSuME Akeno optical observations
  49. GRB 071031: REM NIR and Optical observation
  50. GRB 071031, SMARTS afterglow observations
  51. GRB 071031: VLT high-resolution spectroscopy
  52. GRB071031: Rapid PROMPT Detections
  53. GRB 071031: GROND detection in all bands
  54. GRB 071031: Swift detection of a burst with an optical counterpart
  55. GRB 071028B Swift-BAT detection of a burst
  56. GRB 071028: SARA observations of variable source
  57. Swift UVOT upper limits to GRB071028
  58. GRB 071028: Swift-XRT Team refined analysis
  59. GRB 071028, Swift-BAT refined analysis
  60. GRB 071028: Swift detection of a burst
  61. GRB 071025: Kuiper Telescope Optical Observations
  62. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  63. GRB 071018: Revised BAT position
  64. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  65. GRB 071025: SARA VRI upper limits
  66. GRB 071025 Milagro GeV/TeV Observations
  67. GRB 071025: SQIID JHK photometry
  68. GRB 071025A: Complex Early-Time IR Behavior, Simultaneous with Gamma- and X-rays
  69. Swift UVOT upper limits
  70. GRB 071025: Swift-XRT Team refined analysis
  71. GRB 060602A: host redshift
  72. GRB 071025, Swift-BAT refined analysis
  73. GRB 071025: Early Super-LOTIS Observations
  74. GRB 071025: R/I-band update
  75. GRB071021 : CFHT Ks-band observation
  76. GRB 071025: ROTSE-III Refined Analysis
  77. GRB 071025: I-detection, R-dropout?
  78. GRB 071025: Swift XRT refined position
  79. GRB 071025a: PAIRITEL observations
  80. GRB 071025: ROTSE-III Detection of Optical Counterpart
  81. GRB 071025: Swift detection of a burst
  82. GRB 071021: R-band detection and analysis
  83. GRB 071020: BTA spectroscopy
  84. Possible radio detection of GRB 071021 with the VLA
  85. Optical observations of GRB 071020
  86. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  87. GRB 071020: SARA observations
  88. Radio detection of GRB 071020 with the VLA
  89. GRB071010b: optical observation
  90. GRB 071021: Subaru NIR observation
  91. GRB 071021: Magellan i-band observation
  92. GRB 071021: Magellan R-band observation
  93. GRB 071021: Z-band detection
  94. GRB 071021: correction to GCNC 6968
  95. GRB 071020: Fading slowly?
  96. GRB 071010B: Fading quickly
  97. GRB 071021: optical and NIR observations
  98. GRB 071021: possible high-z burst
  99. GRB 071021, Swift-BAT refined analysis
  100. GRB 071021: retraction of Faulkes Telescope South candidate

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