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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"

37705 results found.

  1. GRB 240421A: Fermi GBM Final Real-time Localization
  2. Fermi trigger No 735280430: Global MASTER-Net observations report
  3. GRB240419A: Skynet Optical Afterglow Analysis
  4. GRB240418A - Candidate afterglow from NIRES
  5. GRB 240419B: Swift/UVOT Upper Limits
  6. IceCube-240419A - IceCube observation of a high-energy neutrino candidate track-like event
  7. IceCube-240419A - IceCube observation of a high-energy neutrino candidate track-like event
  8. GRB 240419A: Swift/UVOT Upper Limits
  9. GRB 240419B: Swift-XRT refined Analysis
  10. GRB 240419B: optical afterglow from the NOT
  11. Swift GRB 240419B: Global MASTER-Net observations report
  12. EP240414A: Terskol Zeiss-2000 optical upper limit
  13. GRB 240419B: Enhanced Swift-XRT position
  14. Swift GRB 240419A: Global MASTER-Net observations report
  15. GRB 240418A: Swift/UVOT Upper Limits
  16. GRB 240419A: REM NIR afterglow detection
  17. GRB 240419A: Swift-XRT refined Analysis
  18. GRB 240418A: Swift-XRT refined Analysis
  19. GRB 240419B: Swift detection of a burst
  20. GRB 240411B: Swift/UVOT Detection
  21. GRB240418A: YAHPT Upper Limits
  22. GRB 240419A: VLT/UVES redshift of z = 5.178
  23. GRB 240419A: VLT optical afterglow detection
  24. GRB 240419A: Enhanced Swift-XRT position
  25. Fermi trigger No 735089036: Global MASTER-Net observations report
  26. GRB 240419A: Prompt enhanced Swift-XRT position
  27. GRB 240419A: Swift detection of a burst
  28. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  29. GRB 240418A: NOT optical upper limits
  30. GRB 240418A: Enhanced Swift-XRT position
  31. GRB 240418A: AKO Upper Limit
  32. GRB 240411A: GOTO early optical upper limits
  33. GRB 240418A: Swift detection of a burst
  34. Fermi GRB 240417A: Global MASTER-Net observations report
  35. EP240416A: Terskol Zeiss-2000 optical upper limit
  36. EP240416A: Khureltogoot optical upper limit
  37. Improved IPN triangulation of GRB 240411A
  38. GRB 240417A: Fermi GBM Final Real-time Localization
  39. GRB 240415A: Glowbug gamma-ray detection
  40. GRB 240414A: Glowbug gamma-ray detection
  41. GRB 240415B: GECAM-B detection
  42. EP 240416a: Xinglong and NOT decaying optical counterpart
  43. GRB 240415A: Swift-BAT refined analysis
  44. GRB 240411A: Glowbug gamma-ray detection
  45. GRB 240414A: Swift-BAT refined analysis
  46. GRB 240414A: AbAO optical upprer limit
  47. GRB 240415A: Swift/UVOT Detection
  48. GRB 240415A: Fermi GBM Observation
  49. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  50. GRB 240415A: Earliest optical followup with the Kinder observations
  51. GRB 240414A: GMG observation
  52. GRB 240415A: Enhanced Swift-XRT position
  53. GRB 240415B: Swift ToO observations
  54. GRB 240415B: Swift/BAT-GUANO Correction
  55. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  56. GRB 240415A: OHP/T193 optical observations
  57. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  58. GRB 240415A: SAO RAS optical observations
  59. GRB 240415A: Mondy optical transient detection (photometry correction in GCN 36118 )
  60. GRB 240414A: Fermi GBM Observation
  61. Fermi GRB 240415A: Global MASTER-Net observations report
  62. GRB 240415A: Mondy optical transient detection
  63. GRB 240414A: Photometric observation from 2.2m CAHA
  64. GRB 240414A: Swift/UVOT Detection
  65. LXT 240402A/GRB 240402B: Swift follow-up observations
  66. GRB 240414A: Mondy optical observations
  67. GRB 240414B: Fermi GBM Final Real-time Localization
  68. GRB 240414A: AKO Optical Upper Limit
  69. GRB 240415A: Prompt Swift-XRT observations
  70. GRB 240415A: Swift detection of a burst
  71. GRB 240415A: Fermi GBM Final Real-time Localization
  72. EP240413a: Upper limits from GECAM-B Observation
  73. GRB 240414A: Swift-XRT refined Analysis
  74. GRB240414A : J-band upper limits from WINTER
  75. GRB 240414A: Enhanced Swift-XRT position
  76. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  77. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  78. GRB 240414A: Skynet Optical Afterglow Observations
  79. Fermi trigger No 734754044: Global MASTER-Net observations report
  80. Swift GRB 240414A: Global MASTER-Net observations report
  81. IPN triangulation of GRB 240410A
  82. IPN triangulation of GRB 240411A
  83. Fermi-LAT gamma-ray observations of IceCube-240412A
  84. GRB 240414A : MITSuME Akeno optical upper limits
  85. GRB 240414A: Redshift confirmation from GTC/OSIRIS+
  86. GRB 240414A : OHP/T193 redshift determination
  87. GRB 240414A : OHP/T193 optical counterpart detection
  88. GRB 240414A: Swift detection of a burst
  89. GRB 240411B: CrAO/ZTSh optical observations
  90. GRB 240411B: Kinder observations with Lulin observatory
  91. GRB 240411B: HiPERCAM/GTC observation
  92. GRB 240411B: Swift-BAT refined analysis
  93. GRB 240411B: Swift-XRT refined Analysis
  94. IceCube-240412A - IceCube observation of a high-energy neutrino candidate track-like event
  95. GRB 240411B: 1.3m DFOT Optical observations
  96. GRB 240411A: GRBAlpha detection
  97. GRB 240411B: OHP/T193 optical observations
  98. GRB 240405A: Glowbug gamma-ray detection
  99. GRB 240411B: Enhanced Swift-XRT position
  100. GRB 240411B: LCO optical afterglow detection

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