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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"

36175 results found.

  1. EP240420a: Nanshan optical counterpart observations
  2. GRB 240421A: Fermi GBM Final Real-time Localization
  3. GRB240419A: Skynet Optical Afterglow Analysis
  4. GRB240418A - Candidate afterglow from NIRES
  5. GRB 240419B: Swift/UVOT Upper Limits
  6. GRB 240419A: Swift/UVOT Upper Limits
  7. GRB 240419B: Swift-XRT refined Analysis
  8. GRB 240419B: optical afterglow from the NOT
  9. Swift GRB 240419B: Global MASTER-Net observations report
  10. EP240414A: Terskol Zeiss-2000 optical upper limit
  11. GRB 240419B: Enhanced Swift-XRT position
  12. Swift GRB 240419A: Global MASTER-Net observations report
  13. GRB 240418A: Swift/UVOT Upper Limits
  14. GRB 240419A: REM NIR afterglow detection
  15. GRB 240419A: Swift-XRT refined Analysis
  16. GRB 240418A: Swift-XRT refined Analysis
  17. GRB 240419B: Swift detection of a burst
  18. GRB 240411B: Swift/UVOT Detection
  19. GRB240418A: YAHPT Upper Limits
  20. GRB 240419A: VLT/UVES redshift of z = 5.178
  21. GRB 240419A: VLT optical afterglow detection
  22. GRB 240419A: Enhanced Swift-XRT position
  23. GRB 240419A: Prompt enhanced Swift-XRT position
  24. GRB 240419A: Swift detection of a burst
  25. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  26. GRB 240418A: NOT optical upper limits
  27. GRB 240418A: Enhanced Swift-XRT position
  28. GRB 240418A: AKO Upper Limit
  29. GRB 240411A: GOTO early optical upper limits
  30. GRB 240418A: Swift detection of a burst
  31. Fermi GRB 240417A: Global MASTER-Net observations report
  32. EP240416A: Terskol Zeiss-2000 optical upper limit
  33. EP240416A: Khureltogoot optical upper limit
  34. Improved IPN triangulation of GRB 240411A
  35. GRB 240417A: Fermi GBM Final Real-time Localization
  36. GRB 240415A: Glowbug gamma-ray detection
  37. GRB 240414A: Glowbug gamma-ray detection
  38. GRB 240415B: GECAM-B detection
  39. EP 240416a: Xinglong and NOT decaying optical counterpart
  40. GRB 240415A: Swift-BAT refined analysis
  41. GRB 240411A: Glowbug gamma-ray detection
  42. GRB 240414A: Swift-BAT refined analysis
  43. GRB 240414A: AbAO optical upprer limit
  44. GRB 240415A: Swift/UVOT Detection
  45. GRB 240415A: Fermi GBM Observation
  46. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  47. GRB 240415A: Earliest optical followup with the Kinder observations
  48. GRB 240414A: GMG observation
  49. GRB 240415A: Enhanced Swift-XRT position
  50. GRB 240415B: Swift ToO observations
  51. GRB 240415B: Swift/BAT-GUANO Correction
  52. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  53. GRB 240415A: OHP/T193 optical observations
  54. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  55. GRB 240415A: SAO RAS optical observations
  56. GRB 240415A: Mondy optical transient detection (photometry correction in GCN 36118 )
  57. GRB 240414A: Fermi GBM Observation
  58. Fermi GRB 240415A: Global MASTER-Net observations report
  59. GRB 240415A: Mondy optical transient detection
  60. GRB 240414A: Photometric observation from 2.2m CAHA
  61. GRB 240414A: Swift/UVOT Detection
  62. LXT 240402A/GRB 240402B: Swift follow-up observations
  63. GRB 240414A: Mondy optical observations
  64. GRB 240414B: Fermi GBM Final Real-time Localization
  65. GRB 240414A: AKO Optical Upper Limit
  66. GRB 240415A: Prompt Swift-XRT observations
  67. GRB 240415A: Swift detection of a burst
  68. GRB 240415A: Fermi GBM Final Real-time Localization
  69. EP240413a: Upper limits from GECAM-B Observation
  70. GRB 240414A: Swift-XRT refined Analysis
  71. GRB240414A : J-band upper limits from WINTER
  72. GRB 240414A: Enhanced Swift-XRT position
  73. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  74. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  75. GRB 240414A: Skynet Optical Afterglow Observations
  76. Swift GRB 240414A: Global MASTER-Net observations report
  77. IPN triangulation of GRB 240410A
  78. IPN triangulation of GRB 240411A
  79. GRB 240414A : MITSuME Akeno optical upper limits
  80. GRB 240414A: Redshift confirmation from GTC/OSIRIS+
  81. GRB 240414A : OHP/T193 redshift determination
  82. GRB 240414A : OHP/T193 optical counterpart detection
  83. GRB 240414A: Swift detection of a burst
  84. GRB 240411B: CrAO/ZTSh optical observations
  85. GRB 240411B: Kinder observations with Lulin observatory
  86. GRB 240411B: HiPERCAM/GTC observation
  87. GRB 240411B: Swift-BAT refined analysis
  88. GRB 240411B: Swift-XRT refined Analysis
  89. GRB 240411B: 1.3m DFOT Optical observations
  90. GRB 240411A: GRBAlpha detection
  91. GRB 240411B: OHP/T193 optical observations
  92. GRB 240405A: Glowbug gamma-ray detection
  93. GRB 240411B: Enhanced Swift-XRT position
  94. GRB 240411B: LCO optical afterglow detection
  95. GRB 240411B: Swift detection of a burst
  96. GRB 240408B: GRBAlpha detection
  97. GRB 240411A: Fermi GBM Final Real-time Localization
  98. EP240408a: Upper limits from GECAM-B Observation
  99. GRB 240405A: GRBAlpha detection
  100. GRB 240408B: AstroSat CZTI detection

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