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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"

45632 results found.

  1. GRB070518: Optical/NIR observation
  2. GRB 070520B: Swift/UVOT Upper Limits
  3. GRB 070520A: Subaru Observations
  4. GRB 070521, Swift-BAT refined analysis
  5. GRB 070520A: Swift UVOT Upper Limits
  6. GRB 070520B: Swift-XRT refined analysis
  7. GRB 070521: optical limit by Pi of the Sky
  8. GRB070521: P200 Observations
  9. GRB070521 : Faulkes Telescope North Observations
  10. GRB 070521: TAROT La Silla observatory optical observations
  11. GRB070521: Bright SDSS Galaxy Near XRT Error Circle
  12. GRB070521 - SDSS Pre-Burst Observations
  13. GRB 070521: Swift detection of a burst
  14. GRB 070520A: MITSuME Akeno optical upper limits
  15. GRB 070520B, Swift-BAT refined analysis
  16. GRB 070520A, Swift-BAT refined analysis
  17. GRB 070520A: Swift-XRT refined analysis
  18. GRB 070518: TNG observations
  19. GRB 070520B: Swift detection of a burst
  20. GRB 070520: Xinglong EST optical Upper Limit
  21. GRB 070520: Swift detection of a burst
  22. VLA observation of GRB 070518
  23. GRB 070518: Swift-XRT refined analysis
  24. GRB 070517: Gemini optical imaging
  25. GRB070518: UVOT refined analysis
  26. GRB070518: OSN observation
  27. GRB 070518, Swift-BAT refined analysis
  28. GRB 070518: OT confirmed form Xinglong TNT observation
  29. GRB 070518: Swift detection of a burst with optical afterglow
  30. GRB070517: Swift-XRT Refined Analysis
  31. GRB 070517, Swift-BAT refined analysis
  32. GRB 070517: Optical search
  33. GRB 070517: Swift detection of a burst
  34. GRB 070509: objects inside XRT error circle
  35. GRB 070512: pseudo-z ~ 1.39 from prompt emission spectrum
  36. GRB 070512: IPN localization and Konus spectrum of a bright burst
  37. GRB070419A: optical observations
  38. GRB 070419A, Deep LBT photometry
  39. GRB 070508: pseudo-z from 4 different spectral analyses
  40. GRB 070509: Swift/UVOT Upper Limits
  41. Konus-Wind and Konus-A observation of GRB 070508
  42. Swift-BAT trigger 278987 is not a GRB
  43. GRB 070510: Swift detection of a possible burst
  44. GRB070509: Swift-XRT Refined Analysis
  45. RHESSI Spectrum of GRB070508
  46. GRB 070508: OA fading and tentative redshift
  47. GRB 070509, Swift-BAT refined analysis
  48. GRB 070508: Suzaku/WAM observation of the prompt emission
  49. GRB 070509: REM observations
  50. GRB 070509: Swift detection of a burst
  51. GRB 070509: ROTSE-III Optical Limits
  52. GRB070508: Swift/UVOT Observations
  53. GRB 070508, SMARTS optical afterglow observation
  54. GRB 070508, Swift-BAT refined analysis
  55. GRB 070508: Multicolor optical observations and possible redshift limit
  56. GRB 070508: Swift-XRT refined analysis
  57. GRB 070508: Optical observation limiting magnitude
  58. GRB 070508: Optical afterglow detection
  59. GRB 070508: REM observations
  60. GRB 070508: TAROT La Silla observatory optical observations
  61. GRB 070508: Swift detection of an intense burst with an optical counterpart
  62. GRB070412: MAGIC telescope GeV observation
  63. Swift-BAT trigger 278809 is not a GRB
  64. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  65. GRB 070506: VLT redshift
  66. GRB070506: Swift/UVOT Observations
  67. GRB070506: Swift XRT refined analysis
  68. GRB 070506, Swift-BAT Refined Analysis
  69. GRB 070506: Swift detection of a burst with optical afterglow
  70. GRB 070412, deep LBT imaging
  71. GRB 070429A: Swift XRT further analysis
  72. GRB070429B: VLT observations
  73. GRB 070429A: optical observations
  74. GRB070429B: position correction
  75. GRB 070309: Swift-XRT afterglow confirmation
  76. GRB070429B: possible host galaxy detection
  77. VLA observation of GRB 070429B
  78. Swift/UVOT observations of GRB070429B
  79. GRB 070429B, Swift-BAT refined analysis
  80. Swift/UVOT observations of GRB070429A
  81. GRB 070429A: Swift XRT refined analysis
  82. GRB 070429A, Swift-BAT refined analysis
  83. GRB 070429A: optical and NIR observations
  84. GRB 070429B: Swift XRT refined analysis
  85. GRB 070429B: ROTSE-III Optical Limits
  86. GRB 070429B: Swift detection of a short burst
  87. GRB 070429: What's the temperature?
  88. GRB 070429: ROTSE-III Optical Limits
  89. GRB 070429: Swift detection of a burst
  90. GRB 070427, Swift-BAT Refined Analysis
  91. LT monitoring of GRB070412
  92. GRB 070427: Swift detection of a burst
  93. GRB 070411, further deep LBT photometry
  94. GRB 070411: Late-time Keck imaging
  95. GRB 070411 : Planned XMM-Newton observation
  96. GRB070419B: Suzaku WAM observation of the prompt emission
  97. GRB 070420, SMARTS optical/IR afterglow observations
  98. GRB 070411, deep LBT photometry
  99. GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
  100. Konus-Wind observation of GRB 070420

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