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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"

21093 results found.

  1. GRB 190311A: Mondy optical observations
  2. GRB 190311A: TSHAO optical observations
  3. GRB190311A: MASTER Global Robotic Net OT optical observation
  4. GRB 190311A: NEXT-0.6m optical afterglow detection
  5. GRB 190311A: Mondy optical observations
  6. GRB 190305A: Swift-XRT afterglow detection
  7. GRB 190306A: Swift-XRT observations
  8. GRB 190306A: Tiled Swift observations
  9. GRB 190305A: Swift-XRT observations
  10. GRB 190305A: Tiled Swift observations
  11. IceCube-190221A: Swift-XRT Follow-up Observations
  12. IceCube-190221A: Fermi-LAT Gamma-ray observations
  13. Fermi-GBM Observations of IceCube-190221A
  14. IceCube-190221A: MASTER Global Robotic Net optical observation
  15. IceCube-190221A - IceCube observation of a high-energy neutrino candidate event
  16. GRB 190220B: BOOTES-4 optical observation
  17. GRB 190219A: NOT optical afterglow candidate
  18. GRB 190219A: CAHA 2.2m observations
  19. GRB190219A: MASTER Global Robotic Net optical observation
  20. GRB 190219A: BOOTES-1 optical limits
  21. GRB 190211A: Tautenburg observations
  22. GRB 190211A: Swift/UVOT Detection
  23. GRB 190211A: NOT optical observations
  24. GRB 180703A: VLT/MUSE host galaxy redshift measurement
  25. GRB 190211A: BOOTES-4/MET optical afterglow confirmation
  26. GRB190211A: MASTER Global Robotic Net optical observation
  27. GRB 190211A: NEXT-0.6m optical afterglow detection
  28. GRB 190202A: Terskol 2-m optical observations
  29. GRB 190203A: Mondy optical observations
  30. GRB 190202A: Xinglong-2.16m optical observations
  31. GRB 190202A: SAO RAS further optical observations
  32. GRB 190204A: SAO RAS optical observations
  33. GRB 190204A: Mondy optical upper limit
  34. GRB190203A: UVOT analysis
  35. GRB 190203A: COATLI Optical Observations
  36. GRB 190204A: Swift/UVOT Detection
  37. GRB 190204A: COATLI Optical Detection of the Fading Afterglow
  38. GRB 190203A: Liverpool Telescope near-IR observations
  39. Swift Trigger 887541: MASTER inspect
  40. GRB 190202A: R and I band observation from HCT
  41. Swift Trigger 887541: MASTER optical observation
  42. GRB 190203A: MASTER OT detection
  43. GRB 190203A: SAO RAS optical observations, afterglow fading
  44. GRB 190202A: SAO RAS optical observations
  45. GRB 190202A: TSHAO optical observations
  46. GRB 190202A: NOT optical observations
  47. GRB 190202A: LCO-CTIO optical observations
  48. GRB 190202A: Swift/UVOT Detection
  49. GRB 190202A: GOTO optical observations
  50. GRB 190202A: Koshka Zeiss-1000 optical observations
  51. GRB 190114C: JCMT SCUBA-2 sub-mm observations
  52. GRB 190129B: GOTO optical observations
  53. GRB 190129B: DDOTI Detection of the Possible Afterglow and Suggestion of Fading
  54. GRB 190129B: Swift/UVOT Upper Limits
  55. GRB 190129B: ePESSTO NTT optical observations
  56. GRB 190129B: MASTER Global Robotic Net optical observation
  57. GRB 190129B: GROND possible host candidate
  58. GRB 190129B: Swift-XRT candidate afterglow detection
  59. GRB 190129B: Tiled Swift observations
  60. Fermi GBM Observations of IceCube-190124A
  61. Swift Trigger 886157: MASTER optical observation
  62. GRB 190114C: Optical follow-up from HCT
  63. Fermi-LAT Gamma-ray Observations of IceCube-190124A
  64. GRB 190123A: IKI-GRB-FuN optical upper limit
  65. GRB 190114C: CHILESCOPE optical observations
  66. GRB 190123A: Swift/UVOT Upper Limits
  67. GRB 190123A: COATLI Optical Observations
  68. GRB 190123A: Swift-BAT refined analysis
  69. GRB 190123A: GOTO optical limit
  70. GRB 190123A: BOOTES-4/MET optical limit
  71. GRB 190123A: MASTER Global Robotic Net optical observation
  72. GRB 190114C: RTT150 optical observations
  73. GRB 190114C: GMRT detection at 1.26GHz
  74. GRB 190114C: MeerKAT radio observation
  75. Swift ToO Website Down
  76. GRB 190114C: UKIRT JHK observation (CORRECTIONS)
  77. GRB 190114C: UKIRT JHK observation continuation - steady fading?
  78. GRB 190114C: Sardinia Radio Telescope observations (CORRECTION)
  79. GRB 190114C: REM optical/NIR detection (CORRECTION)
  80. GRB 190114C: Sardinia Radio Telescope observations
  81. GRB 190114C: RATIR Optical and NIR Detections
  82. GRB 190114C: RT-22 detection at 36.8 GHz
  83. GRB 190114C: ePESSTO NTT optical observations
  84. GRB 190114C: Continued UKIRT JHK observation
  85. GRB 190114C: continued CHILESCOPE optical obs
  86. GRB190114C: ATCA detection of the radio afterglow
  87. GRB 190106A: Discovery Channel Telescope observations
  88. GRB 190114B: continued optical observations in Mondy
  89. GRB 190114C: Optical detection from HCT
  90. GRB 190114C: CHILESCOPE optical observations
  91. GRB 190114C: UKIRT JHK observation
  92. GRB 190114A: NOEMA detection of the mm afterglow
  93. GRB 190114A:DOAO/LOAO optical observation
  94. GRB 190114C: KMTNet optical observation
  95. GRB 190114C: LSGT optical observation
  96. GRB 190114A: DOAO/LOAO optical observation
  97. GRB 190114C: REM optical/NIR detection
  98. GRB 190114C: ALMA detection of a fading mm counterpart
  99. GRB 190114C: Mondy optical observations
  100. GRB 190114C: VLA Detection

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