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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').
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subject:"Swift"
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12169 results found.

  1. GRB 250207A: Fermi GBM Observation
  2. Konus-Wind detection of GRB 250207A
  3. Konus-Wind detection of GRB 250206A
  4. EP250207b: Global MASTER-Net observations report
  5. GRB 250207A: Skynet optical afterglow observations
  6. GRB 250210A: AstroSat CZTI detection
  7. EP250207b: a new X-ray transient detected by Einstein Probe
  8. GRB 250209A: MAXI/GSC detection (possible detection of an X-ray flare from 1RXS J145110.3+310648)
  9. Fermi GRB 250210A: Global MASTER-Net observations report
  10. LIGO/Virgo/KAGRA S250206dm: Global MASTER-Net observations report
  11. IceCube Alert 250207.09: Global MASTER-Net observations report
  12. Fermi-LAT Gamma-ray Observations of IceCube-250207A
  13. LIGO/Virgo/KAGRA S250207bg: Updated NED Galaxies in the Localization Volume
  14. LIGO/Virgo/KAGRA S250206dm: GECKO Observation with 7DT and KMTNet
  15. LIGO/Virgo/KAGRA S250206dm: (Update-7) NED Galaxies in the Localization Volume
  16. GRB 250206A: Fermi-LAT detection
  17. LIGO/Virgo/KAGRA S250206dm: COLIBRÍ/DDRAGO Observations of the DDOTI optical candidates
  18. GRB 250207A: Swift-XRT refined Analysis
  19. LIGO/Virgo/KAGRA S250207bg: NED Galaxies in the Localization Volume
  20. Konus-Wind detection of GRB 250204B
  21. GRB 250129A: Continued AbAO and Mondy optical observations
  22. GRB 250207B: MAXI/GSC detection
  23. The EP-WXT trigger 01709131332 is likely a flaring star
  24. LIGO/Virgo/KAGRA S250206dm: Updated-6 NED Galaxies in the Localization Volume
  25. Fermi-LAT Gamma-ray Observations of IceCube-250203A
  26. LIGO/Virgo/KAGRA S250206dm: Coverage and upper limits from MAXI/GSC observations
  27. LIGO/Virgo/KAGRA S250206dm: Updated NED Galaxies in the Localization Volume
  28. LIGO/Virgo/KAGRA S250206dm: NED Galaxies in the Localization Volume
  29. EP250205a/GRB 250205A: Einstein Probe observation
  30. LIGO/Virgo/KAGRA S250205bk: NED Galaxies in the Localization Volume
  31. Konus-Wind detection of GRB 250201A
  32. Konus-Wind detection of GRB 250202B
  33. GRB 250204B: AstroSat CZTI detection of a short burst
  34. GRB 250202C: GRBAlpha detection
  35. GRB 250129A: 7DT Detection and Medium-band SED of Afterglow
  36. GRB 250202C: Fermi GBM Final Real-time Localization
  37. GRB 250202B: AstroSat CZTI detection of a bright long GRB
  38. Swift GRB250129A: MASTER 4 days observations report
  39. GRB 250201A: INTEGRAL SPI/ACS detection
  40. Konus-Wind detection of GRB 250129A
  41. LIGO/Virgo/KAGRA S250201i: Coverage and upper limits from MAXI/GSC observations
  42. EP250108A / SN 2025kg: Upper limits from a neutrino search with IceCube
  43. GRB 250128B: VLA possible radio detection
  44. GRB 250127A: EP-FXT second observation epoch and confirmation of the x-ray afterglow fading
  45. GRB 250129A: Skynet optical observations
  46. GRB 250129A: Swift-XRT refined Analysis
  47. The EP-WXT trigger 01709131085: KAIT confirmation of the stellar flare
  48. GRB 250128B: VLT/FORS2 optical observations
  49. GRB 250128B: Swift-XRT refined Analysis
  50. Swift GRB 250128B: Global MASTER-Net observations report
  51. EP250125a: Upper limits from Swift/BAT-GUANO
  52. GRB 250128B: Swift detection of a short burst
  53. GRB 250127B: DDOTI Upper Limit on the Afterglow
  54. Fermi-LAT Gamma-ray Observations of IceCube-250102A
  55. GRB 250127A: EP-FXT afterglow detection
  56. GRB 250117A: Fermi GBM Observation
  57. Fermi GRB 250127B: Global MASTER-Net observations report
  58. Fermi-LAT Gamma-ray Observations of IceCube-250101A
  59. GRB 250126A: MAXI/GSC detection
  60. EP250108a / SN 2025kg: Refined Analysis of EP-WXT Detection
  61. GECAM-A detection of a bright burst from SGR 1E1841-045
  62. EP250125a: a new X-ray transient detected by Einstein Probe
  63. Konus-Wind detection of a bright burst from SGR 1E1841-045 on 2025 January 23
  64. GRB 250121A: Swift/BAT-GUANO localization skymap of a burst
  65. IPN triangulation of a bright burst from SGR 1E1841-045
  66. EP250108a: AbAO, CMO and Terskol optical upper limits
  67. Konus-Wind detection of GRB 250118B
  68. GRB 250121A: Fermi GBM Observation
  69. IPN triangulation of GRB 250118B
  70. Konus-Wind detection of GRB 250119B
  71. IPN triangulation of GRB 250119B
  72. GRB 250121A: Fermi-LAT detection
  73. LIGO/Virgo S250119cv: Swift XRT observations, 5 X-ray sources
  74. GRB 250119C: Swift/BAT-GUANO localization skymap of a short burst
  75. GRB 250119B: Swift/BAT-GUANO localization skymap of a long burst
  76. Fermi-LAT Gamma-ray Observations of IceCube-241224A
  77. GRB 250118A: Swift/BAT-GUANO localization skymap of a short burst
  78. Konus-Wind detection of GRB 250117A
  79. IPN triangulation of GRB 250117A (short)
  80. LIGO/Virgo/KAGRA S250119cv: Updated NED Galaxies in the Localization Volume
  81. LIGO/Virgo/KAGRA S250119cv: NED Galaxies in the Localization Volume
  82. GRB 250117A: Swift/BAT-GUANO localization skymap of a short burst
  83. LIGO/Virgo/KAGRA S250119cv: Identification of a GW compact binary merger candidate
  84. EP250108a / AT 2025kg: the kangaroo is hopping, evidence for optical rebrightening
  85. GRB 250117A: GECAM observation of a short burst
  86. Konus-Wind detection of GRB 250116A
  87. GRB 250116A: GECAM-B detection of a long burst
  88. GRB 250116A: Fermi-LAT detection
  89. LIGO/Virgo/KAGRA S250114ax: Updated NED Galaxies in the Localization Volume
  90. GRB 250101A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations and rebrightening.
  91. Konus-Wind detection of GRB 250113A
  92. IPN triangulation of GRB 250113A
  93. GRB 250114A: Swift-XRT refined Analysis
  94. LIGO/Virgo/KAGRA S250114ax: NED Galaxies in the Localization Volume
  95. GRB 250114A: Swift detection of a burst with an optical counterpart
  96. GRB 250101A: Terskol Zeiss-2000 optical observations
  97. GRB 250106A: Swift-XRT afterglow detection
  98. Fermi trigger No 758442826: Global MASTER-Net observations report
  99. EP250108a / AT 2025kg: LCO optical observations
  100. EP250111a: Global MASTER-Net observations report

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