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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"

39265 results found.

  1. GRB 240414A: Photometric observation from 2.2m CAHA
  2. GRB 240414A: Swift/UVOT Detection
  3. LXT 240402A/GRB 240402B: Swift follow-up observations
  4. GRB 240414A: Mondy optical observations
  5. GRB 240414B: Fermi GBM Final Real-time Localization
  6. GRB 240414A: AKO Optical Upper Limit
  7. GRB 240415A: Prompt Swift-XRT observations
  8. GRB 240415A: Swift detection of a burst
  9. GRB 240415A: Fermi GBM Final Real-time Localization
  10. EP240413a: Upper limits from GECAM-B Observation
  11. GRB 240414A: Swift-XRT refined Analysis
  12. GRB240414A : J-band upper limits from WINTER
  13. GRB 240414A: Enhanced Swift-XRT position
  14. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  15. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  16. GRB 240414A: Skynet Optical Afterglow Observations
  17. Fermi trigger No 734754044: Global MASTER-Net observations report
  18. Swift GRB 240414A: Global MASTER-Net observations report
  19. IPN triangulation of GRB 240410A
  20. IPN triangulation of GRB 240411A
  21. Fermi-LAT gamma-ray observations of IceCube-240412A
  22. GRB 240414A : MITSuME Akeno optical upper limits
  23. GRB 240414A: Redshift confirmation from GTC/OSIRIS+
  24. GRB 240414A : OHP/T193 redshift determination
  25. GRB 240414A : OHP/T193 optical counterpart detection
  26. GRB 240414A: Swift detection of a burst
  27. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  28. EP240408a: GSP optical upper limit
  29. GRB 240411B: CrAO/ZTSh optical observations
  30. GRB 240411B: Kinder observations with Lulin observatory
  31. LIGO/Virgo/Kagra S240413p: NED Galaxies in the Localization Volume
  32. GRB 240411B: HiPERCAM/GTC observation
  33. IceCube Alert 240412.23: Global MASTER-Net observations report
  34. GRB 240411B: Swift-BAT refined analysis
  35. GRB 240411B: Swift-XRT refined Analysis
  36. GRB 240411B: 1.3m DFOT Optical observations
  37. GRB 240411A: GRBAlpha detection
  38. GRB 240411B: OHP/T193 optical observations
  39. GRB 240405A: Glowbug gamma-ray detection
  40. GRB 240411B: Enhanced Swift-XRT position
  41. GRB 240411B: LCO optical afterglow detection
  42. GRB 240411B: Swift detection of a burst
  43. GRB 240408B: GRBAlpha detection
  44. GRB 240411A: Fermi GBM Final Real-time Localization
  45. EP240408A: MASTER optical observations
  46. EP240408a: GROND detection of a candidate counterpart
  47. EP240408a: Upper limits from GECAM-B Observation
  48. GRB 240405A: GRBAlpha detection
  49. Swift Trigger 1220736: detection of 4U 1543-62.
  50. GRB 240408B: AstroSat CZTI detection
  51. Fermi GRB 240408A: Global MASTER-Net observations report
  52. GRB 240408A: Fermi GBM Final Real-time Localization
  53. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  54. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  55. Fermi GRB 240407A: Global MASTER-Net observations report
  56. GRB 240407A: Fermi GBM Final Real-time Localization
  57. Fermi-LAT gamma-ray observations of IceCube-240327B
  58. Fermi-LAT gamma-ray observations of IceCube-240327A
  59. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  60. Fermi GRB 240405B: Global MASTER-Net observations report
  61. GRB 240405B: Fermi GBM Final Real-time Localization
  62. GRB 240402C: Glowbug gamma-ray detection
  63. GRB 240405A: Fermi GBM Final Real-time Localization
  64. GRB 240402C: GRBAlpha detection
  65. GRB 240331A: GRBAlpha detection
  66. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  67. GRB 240403B: Glowbug gamma-ray detection
  68. GRB 240403A: Glowbug gamma-ray detection
  69. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  70. Konus-Wind detection of LXT 240402A/GRB 240402B
  71. GRB/FXT 240402B: Kinder optical counterpart candidate
  72. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  73. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  74. GRB 240403A: Fermi GBM Detection
  75. LXT 240402A: EP-FXT detection of the X-ray afterglow
  76. Fermi GRB 240404A: Global MASTER-Net observations report
  77. GRB 240404A: Fermi GBM Final Real-time Localization
  78. LXT 240402A: MASTER optical observations with AGN in error-box
  79. GRB 240402B: GWAC-F50A optical upper limit
  80. GRB 240402B: GECAM-C detection
  81. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  82. Fermi trigger No 733808041: Global MASTER-Net observations report
  83. Fermi GRB 240402A: Global MASTER-Net observations report
  84. GRB 240402A: Fermi GBM Final Real-time Localization
  85. EP240331A: MASTER optical observations
  86. X-ray transient EP20240331a: MeerLICHT optical upper limits
  87. IBAS Alert n.10651 not a GRB
  88. Integral GRB240401.69: Global MASTER-Net observations report
  89. GRB 240329A: Glowbug gamma-ray detection
  90. GRB 240324A: AstroSat CZTI detection of a short burst
  91. GRB 240331A: AstroSat CZTI detection
  92. GRB 240329A: AstroSat CZTI detection
  93. GRB 240331A: Fermi GBM Final Real-time Localization
  94. GRB 240329A: GRBAlpha detection
  95. Fermi trigger No 733366352: Global MASTER-Net observations report
  96. Fermi GRB 240329A: Global MASTER-Net observations report
  97. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  98. GRB 240329A: Fermi GBM Final Real-time Localization
  99. Fermi GRB 240328B: Global MASTER-Net observations report
  100. Fermi GRB 240328A: Global MASTER-Net observations report

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