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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"

18429 results found.

  1. GRB 110407A: Prompt enhanced Swift-XRT position
  2. GRB 110407A: Swift detection of a burst
  3. GRB 110328A/Swift J164449.3+573451: BAT recent rate increase and pre-outburst,light curve
  4. GRB 110402A: Suzaku WAM observation of the prompt emission
  5. GRB 110328/Swift J164449.3+573451: Chandra observations
  6. GRB 110328A / Swift J164449.3+573451: Keck LRIS R-band photometry
  7. GRB 110328A / Swift J164449.3+573451, HST Observations
  8. GRB 110328A / Swift J164449.3+573451: millimeter detection at PdBI
  9. GRB 110402A: Konus-Wind spectral lags and detailed energetics
  10. GRB 110402A: Fermi GBM detection
  11. GRB 110402A afterglow observation
  12. GRB 110328A / Swift J164449.3+573451: Keck/DEIMOS Optical Spectroscopy
  13. GRB 110328A/Swift J164449.3+573451: SARA-N detection
  14. GRB 110402A: Swift/UVOT detection of afterglow candidate
  15. GRB 110402A: Spectral lag indicates short hard burst
  16. Konus-Wind observation of GRB 110402A
  17. GRB 110402A: Konkoly observations
  18. GRB 110328A: Konkoly observations.
  19. GRB 110402A: Swift-BAT refined analysis
  20. GRB 110402A: Swift-XRT refined Analysis
  21. GRB 110402A: early optical limit by "Pi of the Sky"
  22. GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
  23. GRB 110402A: PAIRITEL NIR Upper Limits
  24. GRB 110402A: Enhanced Swift-XRT position
  25. GRB 110402A: Liverpool Telescope Observations
  26. GRB 110402A: Swift detection of a burst
  27. GRB 110328A / Swift J164449.3+573451: KASINICS NIR Observation
  28. GRB 110328A / Swift J164449.3+57345: Correction to GCN 11850
  29. GRB 110328A / Swift J164449.3+573451: Radio-optical/NIR Astrometry
  30. GRB 110328A / Swift J164449.3+573451: Infrared transient
  31. GRB 110328A / Swift J164449.3+573451: Mondy optical observations
  32. GRB 110328/Swift J164449.3+573451: Fermi observations
  33. GRB 110328A / Swift J164449.3+573451: KASINICS K-band Observation
  34. GRB 110328A / Swift J164449.3+573451
  35. GRB 110328A / Swift J164449.3+573451: EVLA observations of a brightening radio source
  36. GRB 110328A / Swift J164449.3+573451: X-ray analysis and a mini-blazar analogy
  37. GRB 110328A / Swift J164449.3+573451: Gemini and UKIRT IR observations
  38. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Detection in 2nd Epoch
  39. GRB 110328A / Swift J164449.3+573451: No optical variability of the optical counterpart
  40. GRB 110328A / Swift J164449.3+573451: beamed emission
  41. GRB 110328A / Swift J164449.3+573451: BAT refined analysis
  42. GRB 110328A / Swift J164449.3+573451: CARMA mm detection
  43. GRB 110328A / Swift J164449.3+573451: Konkoly observations
  44. GRB 110328A / Swift J164449.3+573451: LOAO R-band Observation
  45. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Upper Limits
  46. GRB 110328A / Swift J164449.3+573451: optical observations
  47. GRB 110328A / Swift J164449.3+573451: EVLA Detection
  48. GRB 110328A / Swift J164449.3+573451: optical spectroscopy from GTC
  49. GRB 110328A / Swift J164449.3+573451: NOT optical observations.
  50. GRB 110328A/ Swift J164449.3+573451 : Xinglong TNT Upper limit
  51. GRB 110328A / Swift J164449.3+573451: PTF Quiescent Optical Counterpart
  52. GRB 110328A: Enhanced Swift-XRT position
  53. GRB 110328A: a second trigger, probably a hard X-ray transient (Swift J164449.3+573451)
  54. GRB 110328A: Swift detection of a burst
  55. GRB110318B : MOA optical upper limit
  56. GRB 110319B Swift-XRT afterglow confirmation
  57. GRB 110319B BAT refined analysis
  58. GRB 110319B: Swift/UVOT Upper Limits
  59. GRB 110318B: Swift/UVOT Upper Limits
  60. GRB 110319B: GROND upper limits
  61. GRB 110319B: Swift-XRT afterglow candidate.
  62. GRB 110319B found in ground analysis of Swift-BAT data
  63. GRB 110319A: Swift/UVOT Detection
  64. GRB 110319A: Swift-BAT refined analysis
  65. GRB 110319A: Swift-XRT refined Analysis
  66. GRB 110318B: GROND upper limits
  67. GRB 110319A: Enhanced Swift-XRT position
  68. GRB 110319A: Swift detection of a burst
  69. GRB 110318B: Swift-XRT refined Analysis
  70. GRB 110318A: Fermi GBM detection
  71. GRB 110318B: Swift-BAT refined analysis
  72. GRB 110318B: Enhanced Swift-XRT position
  73. GRB 110318A: Swift-BAT refined analysis
  74. GRB 110318B: Swift/UVOT Non-Detection of an Afterglow
  75. GRB 110318B: Swift detection of a burst
  76. GRB 110318A: Swift detection of a burst
  77. GRB 110315A: Swift/UVOT Upper Limits
  78. GRB 110315A: Swift-XRT refined Analysis
  79. GRB 110315A: Swift-BAT refined analysis
  80. GRB 110315A: Enhanced Swift-XRT position
  81. GRB 110315A: MASTER early optical observations
  82. GRB 110315A: Swift detection of a burst
  83. GRB 110312A: Swift/UVOT Upper Limits
  84. GRB 110312A: Swift-XRT refined Analysis
  85. GRB 110312A: GROND Upper Limits
  86. GRB 110312A: Enhanced Swift-XRT position
  87. GRB 110312A: Swift-BAT refined analysis
  88. GRB 110312A: Swift detection of a burst
  89. GRB 110305A: Swift/UVOT Upper Limits
  90. GRB 110305A: Swift-XRT refined Analysis
  91. GRB 110305A: Enhanced Swift-XRT position
  92. GRB 110305A: Swift-BAT refined analysis
  93. GRB 110305A: GROND Detection of Optical Afterglow
  94. GRB 110305A: Swift detection of a burst
  95. GRB 110223A: optical upper limits
  96. Swift/UVOT observations of GRB110223A
  97. No IPN GRB detected in conjunction with candidate GRB 110215
  98. GRB GRB 110223A: MASTER VWF early optical observations
  99. Swift/UVOT observations of GRB110223b
  100. GRB 110223A: Swift-BAT refined analysis

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