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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

26730 results found.

  1. GRB 130418A: TNG NIR observations
  2. GRB 130502A: Enhanced Swift-XRT position
  3. GRB 130427A: MITSuME Ishigakijima Optical Observation after 5 days
  4. GRB 130502A: TNG candidate counterpart
  5. GRB 130502B: Fermi GBM detection of a burst
  6. GRB 130502A: T100 Observations
  7. GRB 130502A: Swift detection of a burst
  8. GRB 130425A: Suzaku WAM observation of the prompt emission
  9. GRB 130427A: Nishi-Harima Optical Spectroscopic Observations
  10. GRB 130427A: high energy gamma-ray detection by AGILE
  11. GRB 130427A: Continued RATIR Optical and NIR Observations
  12. GRB 130427A: MITSuME Ishigakijima Optical Observation after 2 days
  13. GRB 130427A: Challis Observatory optical observations
  14. GRB 130427A: Continued Skynet/PROMPT Observations
  15. GRB 130427A: Fermi-LAT refined analysis
  16. GRB 130427A: SARA-N detection
  17. GRB 130427A: Continued RATIR Optical and NIR Observations
  18. GRB 130427A: CrAO RT-22 36 GHz observation
  19. GRB 130418A: Bassano Bresciano Observatory lightcurve analisis
  20. GRB 130427A: Improved Swift-XRT analysis
  21. GRB 130425: MASTER-Net optical observations
  22. GRB 100728A: GROND host detection and X-shooter redshift
  23. GRB 130427B: MITSuME Ishigakijima upper limits
  24. GRB 130427A: MITSuME Okayama and Ishigakijima Optical Observation after 1 day
  25. GRB 130427A: Skynet/PROMPT Observations
  26. GRB 130427B: RATIR Optical and NIR Observations
  27. GRB 130427A: Nishi-Harima NIR Observations
  28. GRB 130427A : Xinglong TNT optical observation
  29. GRB 130427A optical time series
  30. GRB 130427A, Optical Observations
  31. GRB 130427A: Swift-XRT refined Analysis
  32. GRB 130427A: Continued RATIR Optical and NIR Observations
  33. GRB 130427A: CARMA 85 GHz detection
  34. GRB 130427B: Swift-XRT refined Analysis
  35. GRB 130427A: NOT optical photometry and redshift
  36. GRB 130427B: MITSuME Okayama upper limits
  37. GRB 130427A: RAPTOR Bright Counterpart Before Swift Trigger
  38. GRB 130427A: T100 observations
  39. GRB 130427A: optical observations in CrAO
  40. GRB 130427A: Fermi GBM observation
  41. GRB 130427A: Fermi-LAT detection of a burst
  42. GRB 130427B: Swift-BAT refined analysis
  43. GRB 130427A: Zadko observatory - Gingin optical observations
  44. GRB 130427B: Enhanced Swift-XRT position
  45. GRB 130427A: GMG optical observation
  46. GRB 130427A: MITSuME Okayama Optical Observation
  47. GRB 130427A: MAXI/GSC detection
  48. GRB 130427B: Faulkes Telescope North afterglow detection
  49. GRB 130427B: Swift detection of a burst with optical counterpart
  50. GRB 130427A: RATIR Optical and NIR Observations
  51. GRB 130427A: Weihai optical observations
  52. GRB 130427A: Continued P60 follow-up of an extremely bright optical afterglow
  53. GRB 130427A: PAIRITEL NIR Detections
  54. GRB 130427A: Faulkes Telescope North detection
  55. GRB 130427A: early optical observations
  56. GRB 130427A: Swift detection of a very bright burst with a likely bright optical counterpart
  57. GRB 130420A: Continued Skynet/GORT Observations/Detections
  58. Trigger 554491: Swift detection of a spike possibly from Sgr A*
  59. GRB 130425A: Fermi GBM detection
  60. GRB 130420A: Continued RATIR Optical and NIR Observations
  61. GRB 130420A: Continued RATIR Optical and NIR Observations
  62. GRB 130418A: Continued RATIR Optical and NIR Observations
  63. GRB 130420B: Fermi GBM observation
  64. Swift Trigger 554135 is probably not a GRB or transient
  65. GRB 130420B: RATIR Optical and NIR Observations
  66. GRB 130420A: Continued RATIR Optical and NIR Observations
  67. GRB 130420B: Swift-XRT refined Analysis
  68. GRB 130420A: Fermi GBM observation
  69. GRB 130420A: ISON-NM optical observations
  70. Skynet/GORT observations of GRB130420A
  71. GRB 130420B: Weihai optical upper limit
  72. GRB 130420B: Swift/UVOT Upper Limits
  73. GRB 130420A: Swift/UVOT Detection
  74. GRB130420B: GMG optical upper limit
  75. GRB 130420A: Swift-XRT refined Analysis
  76. GRB 130420B: Enhanced Swift-XRT position
  77. GRB 130420A: GMG optical observation
  78. GRB 130420A: Enhanced Swift-XRT position
  79. GRB130420A : Xinglong TNT optical upper limit
  80. GRB 130420B: Faulkes Telescope North observations
  81. GRB 130420A: Weihai Optical Observations
  82. GRB 130420B: Swift detection of a burst
  83. GRB 130420A: RATIR Optical and NIR Observations
  84. GRB 130420A: PAIRITEL NIR detections
  85. GRB 130420A: Swift detection of a burst with an optical counterpart
  86. GRB 130420A: Faulkes Telescope North candidate
  87. GRB 130418A: Continued RATIR Optical and NIR Observations
  88. GRB 130418A: Swift-XRT refined Analysis
  89. GRB 130418A: SMARTS optical/IR afterglow observations
  90. GRB 130418A: Submm observations from SMA
  91. GRB 130419A, Swift-BAT refined analysis
  92. GRB 130327B: Swift/XRT source is not the afterglow
  93. Trigger 553930: Swift detection of a possible flare from HR 5110
  94. GRB 130418A: LOAO Observation
  95. GRB 130418A, Swift-BAT refined analysis
  96. GRB 130418A: REM NIR observations
  97. GRB 130418A: RATIR Optical and NIR Observations
  98. GRB 130418A: GROND detection of the optical-NIR afterglow
  99. GRB130418A: OSN 1.5m fading afterglow detection
  100. GRB 130418A: Swift/UVOT Detection and request for continuing coverage

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