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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"

3821 results found.

  1. GRB 240229A: Fermi GBM Final Real-time Localization
  2. GRB 240225B: VLT/X-shooter redshift
  3. GRB 240225B: 3.6m DOT observation
  4. GRB 240225B: MAXI/GSC detection
  5. Transient EPW20240219aa: Mondy optical observations
  6. Fermi trigger No 729914426: Global MASTER-Net observations report
  7. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  8. Fermi trigger No 729650855: Global MASTER-Net observations report
  9. Fermi GRB 240213A: Global MASTER-Net observations report
  10. Fermi trigger No 729152364: Global MASTER-Net observations report
  11. Fermi trigger No 729012023: Global MASTER-Net observations report
  12. GRB 240204A: Mondy optical afterglow observations
  13. Fermi trigger No 728749569: Global MASTER-Net observations report
  14. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  15. Fermi GRB 240204A: Global MASTER-Net observations report
  16. Fermi trigger No 728706420: Global MASTER-Net observations report
  17. IceCube Alert 240204.38: Global MASTER-Net observations report
  18. GRB 240129A: Fermi GBM Observation
  19. Fermi GRB 240127A: Global MASTER-Net observations report
  20. Konus-Wind detection of GRB 240119A (short/hard)
  21. IPN triangulation of GRB 240119A (short)
  22. GRB 240119A: GECAM detection of a short burst
  23. GRB 240119A: AstroSat CZTI detection of a short burst
  24. GRB 240118A: Mondy optical observations
  25. GRB 240119A: Fermi GBM Final Localization
  26. GRID detection of GRB 231230A
  27. IPN triangulation of GRB 240112A (long)
  28. GRB 240112C: Swift/UVOT Detection
  29. Fermi trigger No 726773850: Global MASTER-Net observations report
  30. GRB 240112C: Swift-XRT refined Analysis
  31. Fermi trigger No 726774492: Global MASTER-Net observations report
  32. GRB 240112C: Swift detection of a burst with an optical counterpart
  33. GRB 240112A: GECAM detection of a burst
  34. GRB 230812B: further radio observations with the VLA
  35. GRB 240107A: MAXI/GSC detection
  36. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  37. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  38. Fermi trigger No 725806648: Global MASTER-Net observations report
  39. GRB231230A: Fermi GBM Observation
  40. Fermi trigger No 725592555: Global MASTER-Net observations report
  41. GRB 231230A: Swift detection of a burst
  42. GRB 231230A: Fermi GBM Final Real-time Localization
  43. Fermi trigger No 724781422: Global MASTER-Net observations report
  44. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  45. GRB 231205B: VZLUSAT-2 detection
  46. Konus-Wind detection of GRB 231210B
  47. Swift GRB231215.41: Global MASTER-Net observations report
  48. Fermi trigger No 724278269: Global MASTER-Net observations report
  49. GRB 231210B: Swift detection of a burst with optical counterpart
  50. IPN triangulation of GRB 231129C
  51. GRB 231208A: GRBAlpha detection
  52. GRB 231208A: Glowbug gamma-ray detection
  53. GRB 231208A: AstroSat CZTI detection of a faint burst
  54. GRB 231205B: REM optical/NIR upper limits
  55. GRB 231129C: ASIM MXGS observation and localization
  56. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  57. GRB 231205B : MITSuME Akeno optical upper limits
  58. Fermi trigger No 723435916: Global MASTER-Net observations report
  59. Fermi trigger No 723326169: Global MASTER-Net observations report
  60. Fermi trigger No 723149952: Global MASTER-Net observations report
  61. GRB 231129A: VZLUSAT-2 detection
  62. GRB 231129C: AGILE detection
  63. GRB 231129A : MITSuME Akeno optical upper limits
  64. GRB 231129C: MASTER OT detection
  65. GRB 231129A: BOOTES-5/JGT optical upper limit
  66. GRB 231129C: Fermi-LAT detection
  67. GRB 231129A: JinShan optical upper limit
  68. GRB 231129C: GRBAlpha detection
  69. GRB 231129C: Glowbug gamma-ray detection
  70. GRB 231129A: optical upper limit in Mondy observatory
  71. GRB 231129C: AstroSat CZTI detection
  72. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  73. GRB 231129C: Fermi GBM Observation of a very bright GRB
  74. GRB 231129C: iTelescope likely optical afterglow AT 2023yph discovery
  75. GRB 231129C: MAXI/GSC detection
  76. GRB 231129C: BALROG localization (Fermi Trigger / GRB 231129799)
  77. GRB 231129C: Fermi GBM detection of a very bright burst
  78. GRB 231129C: Fermi GBM Final Real-time Localization
  79. Fermi trigger No 722977823: Global MASTER-Net observations report
  80. GRB 231129B: MAXI/GSC detection
  81. Integral GRB231129.21: Global MASTER-Net observations report
  82. LIGO/Virgo/KAGRA S231129ac: Identification of a GW compact binary merger candidate
  83. Fermi trigger No 722507896: Global MASTER-Net observations report
  84. Fermi trigger No 722462310: Global MASTER-Net observations report
  85. Fermi trigger No 722349867: Global MASTER-Net observations report
  86. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  87. GRB 231118A: Fermi GBM Final Real-time Localization
  88. LIGO/Virgo/KAGRA S231118ab: Identification of a GW compact binary merger candidate
  89. GRB 231117A: AKO Optical Upper Limit
  90. Swift GRB 231117A: Global MASTER-Net observations report
  91. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  92. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  93. GRB 231115A: archival HST observations
  94. GECAM-B observation of a short burst from SGR J1555-5402
  95. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  96. GRB 231111A: GMG observation (correction)
  97. GRB 231111A: GMG observation upper limit
  98. Fermi GRB 231108A: Global MASTER-Net observations report
  99. Fermi GRB 231106A: Global MASTER-Net observations report
  100. GRB 231104A: 3.6m DOT optical upper limit

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