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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

4254 results found.

  1. Fermi trigger No 733366352: Global MASTER-Net observations report
  2. Fermi GRB 240329A: Global MASTER-Net observations report
  3. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  4. GRB 240329A: Fermi GBM Final Real-time Localization
  5. Fermi GRB 240328B: Global MASTER-Net observations report
  6. Fermi GRB 240328A: Global MASTER-Net observations report
  7. GRB 240320A: Glowbug gamma-ray detection
  8. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  9. Fermi trigger No 732657380: Global MASTER-Net observations report
  10. GRB 240320A: Fermi GBM Final Real-time Localization
  11. Fermi GRB 240318A: Global MASTER-Net observations report
  12. Fermi GRB 240317B: Global MASTER-Net observations report
  13. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  14. Fermi trigger No 732299243: Global MASTER-Net observations report
  15. GRB 240315A: Fermi GBM Final Real-time Localization
  16. Fermi trigger No 731839490: Global MASTER-Net observations report
  17. Fermi GRB 240310A: Global MASTER-Net observations report
  18. GRB 240309A: MAXI/GSC detection
  19. GRID detection of GRB 240229A (Updated Report)
  20. GRID detection of GRB 240229A
  21. GRB 240229A: Glowbug gamma-ray detection
  22. GRB 240229A: GRBAlpha detection
  23. Fermi-LAT gamma-ray observations of IceCube-240229A
  24. GRB 240305C: AstroSat CZTI detection of a short burst
  25. GRB 240229A: VZLUSAT-2 detection
  26. Fermi trigger No 731161136: Global MASTER-Net observations report
  27. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  28. GRB 240229A: CALET Gamma-Ray Burst Monitor detection
  29. IceCube-240229A - IceCube observation of a high-energy neutrino candidate track-like event
  30. GRB 240225B: further SAO RAS optical observations
  31. Fermi GRB 240229A: Global MASTER-Net observations report
  32. IceCube Alert 240229.66: Global MASTER-Net observations report
  33. GRB 240229A: BALROG localization (Fermi Trigger 730908432 / GRB 240229588)
  34. GRB 240229A: Fermi GBM Final Real-time Localization
  35. GRB 240225B: VLT/X-shooter redshift
  36. GRB 240225B: 3.6m DOT observation
  37. GRB 240225B: MAXI/GSC detection
  38. Transient EPW20240219aa: Mondy optical observations
  39. Fermi trigger No 729914426: Global MASTER-Net observations report
  40. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  41. Fermi trigger No 729650855: Global MASTER-Net observations report
  42. Fermi GRB 240213A: Global MASTER-Net observations report
  43. Fermi trigger No 729152364: Global MASTER-Net observations report
  44. Fermi trigger No 729012023: Global MASTER-Net observations report
  45. GRB 240204A: Mondy optical afterglow observations
  46. Fermi trigger No 728749569: Global MASTER-Net observations report
  47. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  48. Fermi GRB 240204A: Global MASTER-Net observations report
  49. Fermi trigger No 728706420: Global MASTER-Net observations report
  50. IceCube Alert 240204.38: Global MASTER-Net observations report
  51. GRB 240129A: Fermi GBM Observation
  52. Fermi GRB 240127A: Global MASTER-Net observations report
  53. Konus-Wind detection of GRB 240119A (short/hard)
  54. IPN triangulation of GRB 240119A (short)
  55. GRB 240119A: GECAM detection of a short burst
  56. GRB 240119A: AstroSat CZTI detection of a short burst
  57. GRB 240118A: Mondy optical observations
  58. GRB 240119A: Fermi GBM Final Localization
  59. GRID detection of GRB 231230A
  60. IPN triangulation of GRB 240112A (long)
  61. GRB 240112C: Swift/UVOT Detection
  62. Fermi trigger No 726773850: Global MASTER-Net observations report
  63. GRB 240112C: Swift-XRT refined Analysis
  64. Fermi trigger No 726774492: Global MASTER-Net observations report
  65. GRB 240112C: Swift detection of a burst with an optical counterpart
  66. GRB 240112A: GECAM detection of a burst
  67. GRB 230812B: further radio observations with the VLA
  68. GRB 240107A: MAXI/GSC detection
  69. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  70. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  71. Fermi trigger No 725806648: Global MASTER-Net observations report
  72. GRB231230A: Fermi GBM Observation
  73. Fermi trigger No 725592555: Global MASTER-Net observations report
  74. GRB 231230A: Swift detection of a burst
  75. GRB 231230A: Fermi GBM Final Real-time Localization
  76. Fermi trigger No 724781422: Global MASTER-Net observations report
  77. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  78. GRB 231205B: VZLUSAT-2 detection
  79. Konus-Wind detection of GRB 231210B
  80. Swift GRB231215.41: Global MASTER-Net observations report
  81. Fermi trigger No 724278269: Global MASTER-Net observations report
  82. GRB 231210B: Swift detection of a burst with optical counterpart
  83. IPN triangulation of GRB 231129C
  84. GRB 231208A: GRBAlpha detection
  85. GRB 231208A: Glowbug gamma-ray detection
  86. GRB 231208A: AstroSat CZTI detection of a faint burst
  87. GRB 231205B: REM optical/NIR upper limits
  88. GRB 231129C: ASIM MXGS observation and localization
  89. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  90. GRB 231205B : MITSuME Akeno optical upper limits
  91. Fermi trigger No 723435916: Global MASTER-Net observations report
  92. Fermi trigger No 723326169: Global MASTER-Net observations report
  93. Fermi trigger No 723149952: Global MASTER-Net observations report
  94. GRB 231129A: VZLUSAT-2 detection
  95. GRB 231129C: AGILE detection
  96. GRB 231129A : MITSuME Akeno optical upper limits
  97. GRB 231129C: MASTER OT detection
  98. GRB 231129A: BOOTES-5/JGT optical upper limit
  99. GRB 231129C: Fermi-LAT detection
  100. GRB 231129A: JinShan optical upper limit

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