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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

3088 results found.

  1. MAXI GRB240514.78: Global MASTER-Net observations report
  2. GRB 240514E: MAXI/GSC detection of a probable afterglow
  3. LAT GRB240513.31: Global MASTER-Net observations report
  4. Fermi trigger No 737277727: Global MASTER-Net observations report
  5. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  6. Fermi trigger No 737258655: Global MASTER-Net observations report
  7. Fermi trigger No 737247400: Global MASTER-Net observations report
  8. Fermi trigger No 737196587: Global MASTER-Net observations report
  9. Fermi trigger No 737152719: Global MASTER-Net observations report
  10. Fermi trigger No 736967879: Global MASTER-Net observations report
  11. Fermi trigger No 736564880: Global MASTER-Net observations report
  12. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  13. GRB 240502C: GOTO possible optical counterpart candidates
  14. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  15. Fermi GRB 240501A: Global MASTER-Net observations report
  16. Fermi trigger No 736197684: Global MASTER-Net observations report
  17. LIGO/Virgo/KAGRA S240422ed: EP-FXT Detection of the Potential Opitcal Electromagnetic Counterpart AT 2024hfq Reported by DECam
  18. LIGO/Virgo/KAGRA S240422ed: Continued Magellan Observations
  19. IceCube-240424A: Upper limits from a search for additional neutrino events in IceCube
  20. LIGO/Virgo/KAGRA S240422ed: Second night Pan-STARRS observations of the skymap
  21. LIGO/Virgo/KAGRA S240422ed: Further near-infrared observations with Subaru/MOIRCS by J-GEM Collaboration
  22. GRB 240421B: Swift-BAT refined analysis
  23. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA/FRAM Observations
  24. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  25. LIGO/Virgo/KAGRA S240422ed: Continued Imaging of Mag24a
  26. IceCube Alert 240424.08: Global MASTER-Net observations report
  27. LIGO/Virgo/KAGRA S240422ed: Subaru/MOIRCS near-infrared observations by J-GEM Collaboration
  28. LIGO/Virgo/KAGRA S240422ed: Potential Candidates from Magellan galaxy-based search
  29. GRB 240419A: Swift-BAT refined analysis
  30. GRB 240421B: ATCA radio observations
  31. LIGO/Virgo/KAGRA S240422ed: Magellan Observations
  32. LIGO/Virgo/KAGRA S240422ed: Coverage and upper limits from MAXI/GSC observations
  33. Fermi trigger No 735470374: Global MASTER-Net observations report
  34. Fermi trigger No 735280430: Global MASTER-Net observations report
  35. IceCube Alert 240419.98: Global MASTER-Net observations report
  36. GRB 240411A: GOTO early optical upper limits
  37. Fermi GRB 240417A: Global MASTER-Net observations report
  38. LIGO/Virgo/KAGRA S240413p: X-ray upper limits from EP-WXT for the candidate AGN counterpart
  39. EP240416A: Khureltogoot optical upper limit
  40. Improved IPN triangulation of GRB 240411A
  41. EP240416A: MASTER optical observations
  42. GRB 240414A: Swift-BAT refined analysis
  43. Fermi GRB 240415A: Global MASTER-Net observations report
  44. GRB 240415A: Fermi GBM Final Real-time Localization
  45. Fermi trigger No 734754044: Global MASTER-Net observations report
  46. GRB 240414A : OHP/T193 redshift determination
  47. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  48. IceCube Alert 240412.23: Global MASTER-Net observations report
  49. EP240408a: Swift follow-up observation
  50. Fermi GRB 240405B: Global MASTER-Net observations report
  51. GRB 240403B: Glowbug gamma-ray detection
  52. GRB 240403A: Glowbug gamma-ray detection
  53. Konus-Wind detection of LXT 240402A/GRB 240402B
  54. GRB 240403A: Fermi GBM Detection
  55. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  56. Fermi GRB 240402A: Global MASTER-Net observations report
  57. Fermi trigger No 733097506: Global MASTER-Net observations report
  58. Fermi GRB 240320A: Global MASTER-Net observations report
  59. Fermi GRB 240317B: Global MASTER-Net observations report
  60. Fermi trigger No 732299243: Global MASTER-Net observations report
  61. Fermi GRB 240314A: Global MASTER-Net observations report
  62. Fermi GRB 240310A: Global MASTER-Net observations report
  63. GRB 240309A: MAXI/GSC detection
  64. Fermi GRB 240306A: Global MASTER-Net observations report
  65. Fermi GRB 240305A: Global MASTER-Net observations report
  66. Swift J151857.0-572147: Swift-BAT refined analysis
  67. GRB 240225B: Swift-XRT afterglow detection
  68. GRB 240225B: Glowbug gamma-ray detection
  69. Fermi GRB 240229A: Global MASTER-Net observations report
  70. IceCube Alert 240229.66: Global MASTER-Net observations report
  71. GRB 240225B: Swift ToO observations
  72. Konus-Wind detection of GRB 240225B (long)
  73. GRB 240225B: VLT/X-shooter redshift
  74. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  75. GRB 240225B: 3.6m DOT observation
  76. GRB 240225B: NOT optical observations
  77. GRB 240225B: Nanshan/HMT optical afterglow detection
  78. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  79. GRB 240225B: Swift-XRT observations
  80. GRB 240225B: GOTO detection of a candidate optical afterglow
  81. Fermi trigger No 730618809: Global MASTER-Net observations report
  82. GRB 240225B: AstroSat CZTI detection
  83. GRB 240225B: Tiled Swift observations
  84. GRB 240225B: MAXI/GSC detection
  85. GRB 240216A: Glowbug gamma-ray detection
  86. GRB 240218A: Swift-BAT refined analysis
  87. GRB 240215A: Fermi GBM Observation
  88. GRB 240216A: GRBAlpha detection
  89. Fermi trigger No 729914426: Global MASTER-Net observations report
  90. GRB 240216A: Fermi GBM Final Real-time Localization
  91. GRB 240128A: Further Swift-XRT observations
  92. GRB 240214A: Tiled Swift observations
  93. GRB 240214A/1H 0451-560: MAXI/GSC detection
  94. Fermi trigger No 729152364: Global MASTER-Net observations report
  95. Fermi trigger No 729012023: Global MASTER-Net observations report
  96. Konus-Wind detection of GRB 240205B (long / very soft)
  97. GRB 240204A: Swift-BAT refined analysis
  98. Fermi trigger No 728749569: Global MASTER-Net observations report
  99. GRB 240204a: Liverpool Telescope optical afterglow detection
  100. GRB 240128A: Glowbug gamma-ray detection

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