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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"

5557 results found.

  1. GRB 181003A: LCO Cerro Tololo observations
  2. GRB 181003A: MASTER optical observation
  3. GRB 181003A: Swift detection of a burst
  4. GRB 180923A: MAXI/GSC detection
  5. GRB180914B: Swift UVOT detection of an optical afterglow
  6. GRB 180914B: Optical counterpart observation from OAJ
  7. GRB 180914B: KAIT Optical Afterglow Candidate
  8. GRB 180914B: Swift-XRT afterglow detection
  9. GRB 180914A: MASTER automatic inspection
  10. GRB 180914A: Swift-XRT observations
  11. Fermi-LAT Gamma-ray Observations of IceCube-180908A
  12. GRB 180904A: SAO RAS optical observations
  13. GRB 180829A/MAXI J0406-019: MAXI/GSC detection
  14. GRB 180823A: Swift detection of a burst
  15. GRB 180818B: 1.5m OSN optical afterglow candidate
  16. GRB 180818A: Swift detection of a burst
  17. GRB 180728A: MASTER early polarization and 19 days monitoring
  18. GRB 180809B: ePESSTO NTT NIR observations
  19. GRB180809B: MASTER Triple Independent Automatic OT Detection
  20. GRB 180809A: MAXI/GSC detection
  21. GRB 180805B: 1.5m OSN I-band observation
  22. GRB 180805B: Swift detection of a burst
  23. GRB 180727A: Swift-BAT refined analysis
  24. GRB 180727A: Swift-XRT refined Analysis
  25. GRB 180727A: Swift detection of a burst
  26. GRB 180723.13: MASTER optical observation of the short Fermi GBM trigger number 554008254
  27. GRB 180722A: MASTER second inspection
  28. GRB 180720B: MASTER Global Net OT observations
  29. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  30. Fermi Trigger 553879512: MASTER optical observation
  31. GRB 180715A: COATLI Optical Observations
  32. IceCube-171106A: MASTER optical observation
  33. GRB 180703A: MASTER optical observation
  34. GRB 180705A: MASTER optical observation
  35. GRB 180703B: Fermi GBM detection
  36. GRB 180703A: Fermi GBM detection
  37. GRB 180703B: Fermi-LAT detection
  38. GRB 180703A: Fermi-LAT detection
  39. GRB 180630A: Swift/UVOT Detection
  40. GRB 180626C / Fermi trigger 551697835: MASTER inspection
  41. GRB 180630A: Swift detection of a burst with an optical counterpart
  42. GRB 180611A: AstroSat CZTI detection
  43. Konus-Wind observation of GRB 180611A
  44. GRB 180611A: Fermi GBM observation
  45. IPN Triangulation of GRB 180611A (long)
  46. GRB 180602A: Swift detection of a burst
  47. Konus-Wind observation of GRB 180526A
  48. IPN Triangulation of GRB 180526A (long)
  49. GRB 180526A: CALET Gamma-Ray Burst Monitor detection
  50. GRB 180512A: GROND upper limits
  51. Swift trigger 831888: misidentification of 4U 1416-62
  52. Chandra observations of GW170817 260 days since merger: first statistically significant evidence for an X-ray decay
  53. IPN Triangulation of GRB 180427A
  54. GRB 180410A: Fermi GBM observation
  55. GRB 180407A: COATLI Upper Limits
  56. GRB 180404B: Swift/UVOT Detection
  57. GRB 180404B: Swift detection of a burst with an optical counterpart
  58. GRB 180331B: AbAO optical observations
  59. GRB 180329B: VLT/X-shooter spectroscopic observations
  60. GRB 180329B: RATIR Optical Observations
  61. Swift Trigger 819863 is not a GRB
  62. GRB 180325A: VLT/X-shooter spectroscopic observations
  63. Konus-Wind observation of GRB 180326A
  64. IPN Triangulation of GRB 180326A (long)
  65. GRB 180325A: GROND observations
  66. GRB 180325A: Global MASTER-Net OT prompt observations
  67. GRB 180325A: RATIR Optical Observations
  68. GRB 180325A: prompt REM optical/NIR detection
  69. GRB 180324A: RATIR Optical Observations and Possible Afterglow Detection
  70. GRB 180316A: RATIR Optical Observations
  71. GRB 180316A: TSHAO optical observations
  72. GRB 180316A: RATIR Optical Observations, Possible Re-brightening
  73. GRB 180316A: RATIR Optical Observations
  74. GRB 180314A: MITSuME Okayama optical upper limits
  75. GRB180316A: MASTER-IAC OT light curve
  76. GRB180316A: MASTER-IAC optical detection
  77. GRB 180314B: RATIR Optical Observations
  78. GRB 180314B: Zeiss-1000/CrAO optical upper limit
  79. GRB 180314A: MASTER-Net OT dtetction
  80. GRB 180311A: Swift detection of a burst
  81. GRB 180305A: RATIR Optical Observations
  82. GRB 180305A: Mondy optical observations
  83. GRB 180305A: RATIR Optical Afterglow Candidate
  84. GRB180224A: Global MASTER-Net bright OT detection
  85. GRB 180222A: Swift detection of a burst
  86. GRB 180205A: Mondy optical observations
  87. IPN Triangulation of GRB 180218A (long/bright)
  88. GRB 180115A: Swift detection of a burst with an optical counterpart.
  89. GRB 180113A: KAIT Optical Observations
  90. GRB 180102A: MASTER-Net robotic report
  91. GRB 171222A: MASTER-Net OT observations
  92. GRB 171216A: Swift detection of a burst
  93. GRB 171209A: MASTER-Net optical observations
  94. LIGO/Virgo GW170817: X-ray observations confirm prediction made from radio data
  95. LIGO/Virgo G298048: Late-time detection of the X-ray afterglow with Chandra
  96. GRB 171123A: OSN Upper Limit
  97. GRB 171112A: MAXI/GSC detection
  98. IceCube-171106A: Swift Observations
  99. GRB 171010A: afterglow and SN 2017htp optical observations
  100. AMON ICECUBE EHE 130214 (close by time to Fermi trigger): MASTER early follow-up observations

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