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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"

27294 results found.

  1. GRB 240415A: Swift-BAT refined analysis
  2. EP240416A: MASTER optical observations
  3. GRB 240414A: Swift-BAT refined analysis
  4. EP240416a: Kinder optical counterpart candidate
  5. EP240416a: EP-WXT detection of a fast X-ray transient
  6. GRB 240414A: AbAO optical upprer limit
  7. GRB 240415A: Swift/UVOT Detection
  8. GRB 240415A: Fermi GBM Observation
  9. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  10. GRB 240414A: GMG observation
  11. EP240414a: EP-FXT follow-up observation
  12. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  13. GRB 240415A: OHP/T193 optical observations
  14. GRB 240414A: Fermi GBM Observation
  15. Fermi GRB 240415A: Global MASTER-Net observations report
  16. GRB 240415A: Mondy optical transient detection
  17. GRB 240414A: Swift/UVOT Detection
  18. LXT 240402A/GRB 240402B: Swift follow-up observations
  19. GRB 240414A: Mondy optical observations
  20. GRB 240414B: Fermi GBM Final Real-time Localization
  21. GRB 240414A: AKO Optical Upper Limit
  22. GRB 240415A: Prompt Swift-XRT observations
  23. GRB 240415A: Swift detection of a burst
  24. GRB 240415A: Fermi GBM Final Real-time Localization
  25. EP240413a: Upper limits from GECAM-B Observation
  26. EP 240414a: NOT optical counterpart confirmation
  27. GRB 240414A: Swift-XRT refined Analysis
  28. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  29. EP240413A: GOTO optical upper limits
  30. GRB 240414A: Skynet Optical Afterglow Observations
  31. Fermi trigger No 734754044: Global MASTER-Net observations report
  32. Swift GRB 240414A: Global MASTER-Net observations report
  33. EP240414a: Kinder optical counterpart candidate possibly associated with the galaxy SDSS J124601.99-094309.3
  34. EP240413a: possible detection of the X-ray emission with EP-FXT after 14 hours
  35. EP240414a: EP-WXT detection of a fast X-ray transient
  36. IPN triangulation of GRB 240411A
  37. GRB 240414A : MITSuME Akeno optical upper limits
  38. EP240413a: EP-WXT detection of a fast X-ray transient
  39. GRB 240414A : OHP/T193 redshift determination
  40. GRB 240414A : OHP/T193 optical counterpart detection
  41. GRB 240414A: Swift detection of a burst
  42. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  43. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  44. EP240408a: GSP optical upper limit
  45. IceCube Alert 240412.23: Global MASTER-Net observations report
  46. GRB 240411B: Swift-BAT refined analysis
  47. GRB 240411B: Swift-XRT refined Analysis
  48. GRB 240411B: 1.3m DFOT Optical observations
  49. GRB 240411B: OHP/T193 optical observations
  50. GRB 240411B: LCO optical afterglow detection
  51. GRB 240411B: Swift detection of a burst
  52. GRB 240408B: GRBAlpha detection
  53. GRB 240411A: Fermi GBM Final Real-time Localization
  54. EP240408A: MASTER optical observations
  55. EP240408a: Upper limits from GECAM-B Observation
  56. EP240408a: BOOTES-6/DPRT optical upper limit
  57. EP240408a: EP-WXT detection of a fast X-ray transient
  58. Swift Trigger 1220736: detection of 4U 1543-62.
  59. Fermi GRB 240408A: Global MASTER-Net observations report
  60. GRB 240408A: Fermi GBM Final Real-time Localization
  61. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  62. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  63. Fermi GRB 240407A: Global MASTER-Net observations report
  64. GRB 240407A: Fermi GBM Final Real-time Localization
  65. Fermi GRB 240405B: Global MASTER-Net observations report
  66. GRB 240405B: Fermi GBM Final Real-time Localization
  67. GRB 240402C: Glowbug gamma-ray detection
  68. GRB 240405A: Fermi GBM Final Real-time Localization
  69. GRB 240402C: GRBAlpha detection
  70. Swift satellite resumes pointed science observations
  71. GRB 240403B: Glowbug gamma-ray detection
  72. GRB 240403A: Fermi GBM Detection
  73. LXT 240402A: EP-FXT detection of the X-ray afterglow
  74. Fermi GRB 240404A: Global MASTER-Net observations report
  75. GRB 240404A: Fermi GBM Final Real-time Localization
  76. LXT 240402A: MASTER optical observations with AGN in error-box
  77. GRB 240402B: GECAM-C detection
  78. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  79. Fermi trigger No 733808041: Global MASTER-Net observations report
  80. Fermi GRB 240402A: Global MASTER-Net observations report
  81. GRB 240402A: Fermi GBM Final Real-time Localization
  82. X-ray transient EP240331a: Kinder optical upper limits
  83. EP240331A: MASTER optical observations
  84. Integral GRB240401.69: Global MASTER-Net observations report
  85. GRB 240331A: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 733366352: Global MASTER-Net observations report
  87. Fermi GRB 240329A: Global MASTER-Net observations report
  88. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  89. GRB 240329A: Fermi GBM Final Real-time Localization
  90. Fermi GRB 240328B: Global MASTER-Net observations report
  91. Fermi GRB 240328A: Global MASTER-Net observations report
  92. GRB 240328B: Fermi GBM Final Real-time Localization
  93. GRB 240328A: Fermi GBM Final Real-time Localization
  94. IceCube Alert 240327.68: Global MASTER-Net observations report
  95. Fermi trigger No 733097506: Global MASTER-Net observations report
  96. Fermi trigger No 733092476: Global MASTER-Net observations report
  97. Fermi trigger No 732937833: Global MASTER-Net observations report
  98. GRB 240318A: Fermi GBM Observation
  99. Fermi GRB 240320A: Global MASTER-Net observations report
  100. Fermi trigger No 732657380: Global MASTER-Net observations report

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