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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"

5859 results found.

  1. GRB 240317A: Fermi GBM Final Real-time Localization
  2. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  3. Fermi trigger No 732299243: Global MASTER-Net observations report
  4. Fermi GRB 240314A: Global MASTER-Net observations report
  5. Fermi trigger No 731839490: Global MASTER-Net observations report
  6. Swift GRB240309.61: Global MASTER-Net observations report
  7. GRB 240309A: MAXI/GSC detection
  8. GRB 240305A: Fermi GBM observation
  9. GRB 240305A: Fermi GBM Final Real-time Localization
  10. Fermi trigger No 731161136: Global MASTER-Net observations report
  11. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  12. GRB 240225B: WINTER near-IR observations and upper limits
  13. Fermi GRB 240226A: Global MASTER-Net observations report
  14. GRB 240218A: VLA detection
  15. GRB 240222A: Swift-XRT refined Analysis
  16. Fermi trigger No 729914426: Global MASTER-Net observations report
  17. GRB 240209A: Fermi GBM observation
  18. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  19. GRB 240213A: Fermi GBM Final Real-time Localization
  20. GRB 240209A: Fermi GBM Final Localization
  21. Fermi trigger No 729152364: Global MASTER-Net observations report
  22. Fermi-LAT gamma-ray observations of IceCube-240204A
  23. Fermi trigger No 729012023: Global MASTER-Net observations report
  24. Konus-Wind detection of GRB 240125A
  25. GRB 240204A: Mondy optical afterglow observations
  26. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  27. Fermi GRB 240204A: Global MASTER-Net observations report
  28. Fermi trigger No 728706420: Global MASTER-Net observations report
  29. IceCube-240204A - IceCube observation of a high-energy neutrino candidate track-like event
  30. GRB 240129A: Fermi GBM Observation
  31. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  32. IPN triangulation of GRB 240125A (short)
  33. GRB 240128A: Swift-XRT observations
  34. GRB 240128A: MAXI/GSC detection
  35. GRB 240125A: GRBAlpha detection
  36. GRB 240125A: CALET Gamma-Ray Burst Monitor detection
  37. GRB 240125A: AstroSat CZTI detection of a short burst
  38. GRB 240125A (short): Glowbug gamma-ray detection
  39. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  40. GRB 240118A: NuSTAR Offline Analysis of the GRB
  41. GRB 240118A: NuSTAR Detection of a Long GRB
  42. GRB 240118A: Fermi GBM Final Real-time Localization
  43. Fermi GRB 240115A: Global MASTER-Net observations report
  44. Fermi trigger No 726774492: Global MASTER-Net observations report
  45. GRB 240109A: Fermi GBM Observation
  46. Swift GRB240109.17: Global MASTER-Net observations report
  47. LIGO/Virgo/KAGRA S240109a: Identification of a GW compact binary merger candidate
  48. GRB 240107A: MAXI/GSC detection
  49. Fermi trigger No 726194053: Global MASTER-Net observations report
  50. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  51. GRB 240101B: Swift detection of a burst
  52. Fermi trigger No 725592555: Global MASTER-Net observations report
  53. LIGO/Virgo/KAGRA S231224e: Identification of a GW compact binary merger candidate
  54. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  55. GRID detection of GRB 231215A
  56. GRB 231222A: Fermi GBM Final Real-time Localization
  57. Fermi trigger No 724781422: Global MASTER-Net observations report
  58. GRB 231215A: GRBAlpha detection
  59. Konus-Wind detection of GRB 231215A
  60. GRB 231215A: Fermi GBM observation
  61. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  62. GRB 231215A: AGILE detection
  63. GRB 231215A: AstroSat CZTI detection
  64. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  65. GRB 231215B: Fermi GBM Final Real-time Localization
  66. GRB 231215A: Swift detection of a burst
  67. Fermi trigger No 724278269: Global MASTER-Net observations report
  68. GRB 231214A: Swift detection of a burst
  69. IPN triangulation of GRB 231205A
  70. GRB 231205B: Swift-BAT refined analysis
  71. GRB 231205B: optical upper limit in TSHAOand AbAO
  72. Fermi trigger No 723581802: Global MASTER-Net observations report
  73. GRB 231129A : MITSuME Akeno optical upper limits
  74. GRB 231129C: MAXI/GSC detection
  75. LIGO/Virgo/KAGRA S231127cg: Identification of a GW compact binary merger candidate
  76. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  77. Fermi trigger No 722462310: Global MASTER-Net observations report
  78. GRB 231117A: Mondy optical observations
  79. GRB 231117A: Chandra afterglow detection
  80. Fermi trigger No 722349867: Global MASTER-Net observations report
  81. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  82. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  83. GRB 231117A: AKO Follow-Up Observation
  84. LIGO/Virgo/KAGRA S231118an: Identification of a GW compact binary merger candidate
  85. GRB 231117A: AKO Optical Upper Limit
  86. GRB 231117A : MITSuME Akeno optical upper limits
  87. MAGIC observation of GRB 231115A, a possible magnetar giant flare
  88. GRB231115A: Liverpool Telescope imaging
  89. GRB 231115A: NuSTAR Follow-Up Observations
  90. Fermi GRB 231116A: Global MASTER-Net observations report
  91. GRB 231116A: Fermi GBM Final Real-time Localization
  92. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  93. Fermi GRB 231114A: Global MASTER-Net observations report
  94. GRB 231114A (short): Glowbug gamma-ray detection
  95. GRB 231114A: Fermi GBM Final Localization
  96. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  97. GRB 231110A: SAO RAS optical observations
  98. IceCube-231103A: No candidates from the Zwicky Transient Facility
  99. Fermi trigger No 721204446: Global MASTER-Net observations report
  100. Fermi GRB 231108A: Global MASTER-Net observations report

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