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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"

27284 results found.

  1. EP240414a: EP-FXT follow-up observation
  2. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  3. GRB 240415A: OHP/T193 optical observations
  4. GRB 240414A: Fermi GBM Observation
  5. Fermi GRB 240415A: Global MASTER-Net observations report
  6. GRB 240415A: Mondy optical transient detection
  7. GRB 240414A: Swift/UVOT Detection
  8. LXT 240402A/GRB 240402B: Swift follow-up observations
  9. GRB 240414A: Mondy optical observations
  10. GRB 240414B: Fermi GBM Final Real-time Localization
  11. GRB 240414A: AKO Optical Upper Limit
  12. GRB 240415A: Prompt Swift-XRT observations
  13. GRB 240415A: Swift detection of a burst
  14. GRB 240415A: Fermi GBM Final Real-time Localization
  15. EP240413a: Upper limits from GECAM-B Observation
  16. EP 240414a: NOT optical counterpart confirmation
  17. GRB 240414A: Swift-XRT refined Analysis
  18. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  19. EP240413A: GOTO optical upper limits
  20. GRB 240414A: Skynet Optical Afterglow Observations
  21. Fermi trigger No 734754044: Global MASTER-Net observations report
  22. Swift GRB 240414A: Global MASTER-Net observations report
  23. EP240414a: Kinder optical counterpart candidate possibly associated with the galaxy SDSS J124601.99-094309.3
  24. EP240413a: possible detection of the X-ray emission with EP-FXT after 14 hours
  25. EP240414a: EP-WXT detection of a fast X-ray transient
  26. IPN triangulation of GRB 240411A
  27. GRB 240414A : MITSuME Akeno optical upper limits
  28. EP240413a: EP-WXT detection of a fast X-ray transient
  29. GRB 240414A : OHP/T193 redshift determination
  30. GRB 240414A : OHP/T193 optical counterpart detection
  31. GRB 240414A: Swift detection of a burst
  32. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  33. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  34. EP240408a: GSP optical upper limit
  35. IceCube Alert 240412.23: Global MASTER-Net observations report
  36. GRB 240411B: Swift-BAT refined analysis
  37. GRB 240411B: Swift-XRT refined Analysis
  38. GRB 240411B: 1.3m DFOT Optical observations
  39. GRB 240411B: OHP/T193 optical observations
  40. GRB 240411B: LCO optical afterglow detection
  41. GRB 240411B: Swift detection of a burst
  42. GRB 240408B: GRBAlpha detection
  43. GRB 240411A: Fermi GBM Final Real-time Localization
  44. EP240408A: MASTER optical observations
  45. EP240408a: Upper limits from GECAM-B Observation
  46. EP240408a: BOOTES-6/DPRT optical upper limit
  47. EP240408a: EP-WXT detection of a fast X-ray transient
  48. Swift Trigger 1220736: detection of 4U 1543-62.
  49. Fermi GRB 240408A: Global MASTER-Net observations report
  50. GRB 240408A: Fermi GBM Final Real-time Localization
  51. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  52. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  53. Fermi GRB 240407A: Global MASTER-Net observations report
  54. GRB 240407A: Fermi GBM Final Real-time Localization
  55. Fermi GRB 240405B: Global MASTER-Net observations report
  56. GRB 240405B: Fermi GBM Final Real-time Localization
  57. GRB 240402C: Glowbug gamma-ray detection
  58. GRB 240405A: Fermi GBM Final Real-time Localization
  59. GRB 240402C: GRBAlpha detection
  60. Swift satellite resumes pointed science observations
  61. GRB 240403B: Glowbug gamma-ray detection
  62. GRB 240403A: Fermi GBM Detection
  63. LXT 240402A: EP-FXT detection of the X-ray afterglow
  64. Fermi GRB 240404A: Global MASTER-Net observations report
  65. GRB 240404A: Fermi GBM Final Real-time Localization
  66. LXT 240402A: MASTER optical observations with AGN in error-box
  67. GRB 240402B: GECAM-C detection
  68. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  69. Fermi trigger No 733808041: Global MASTER-Net observations report
  70. Fermi GRB 240402A: Global MASTER-Net observations report
  71. GRB 240402A: Fermi GBM Final Real-time Localization
  72. X-ray transient EP240331a: Kinder optical upper limits
  73. EP240331A: MASTER optical observations
  74. Integral GRB240401.69: Global MASTER-Net observations report
  75. GRB 240331A: Fermi GBM Final Real-time Localization
  76. Fermi trigger No 733366352: Global MASTER-Net observations report
  77. Fermi GRB 240329A: Global MASTER-Net observations report
  78. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  79. GRB 240329A: Fermi GBM Final Real-time Localization
  80. Fermi GRB 240328B: Global MASTER-Net observations report
  81. Fermi GRB 240328A: Global MASTER-Net observations report
  82. GRB 240328B: Fermi GBM Final Real-time Localization
  83. GRB 240328A: Fermi GBM Final Real-time Localization
  84. IceCube Alert 240327.68: Global MASTER-Net observations report
  85. Fermi trigger No 733097506: Global MASTER-Net observations report
  86. Fermi trigger No 733092476: Global MASTER-Net observations report
  87. Fermi trigger No 732937833: Global MASTER-Net observations report
  88. GRB 240318A: Fermi GBM Observation
  89. Fermi GRB 240320A: Global MASTER-Net observations report
  90. Fermi trigger No 732657380: Global MASTER-Net observations report
  91. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  92. GRB 240320A: Fermi GBM Final Real-time Localization
  93. Fermi Gamma-ray Burst Monitor trigger 732299243/240316686 is not a GRB
  94. X-ray transient EP240315a: GTC/OSIRIS spectroscopic redshift confirmation
  95. GRB 240317B: Fermi GBM Observation
  96. X-ray transient EP240315a: EP-FXT detection of the X-ray afterglow
  97. Fermi GRB 240318A: Global MASTER-Net observations report
  98. GRB 240318A: Fermi GBM Final Real-time Localization
  99. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  100. Fermi GRB 240317B: Global MASTER-Net observations report

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