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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.

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

24458 results found.

  1. GRB 250129A: GRANDMA/TAROT optical afterglow detection
  2. GRB 250128B: VLA radio upper limit
  3. Ep250125A: 1.3m DFOT optical upper limit
  4. GRB 250128B: Gemini-North optical extended source detection
  5. The EP-WXT trigger 01709131085: KAIT confirmation of the stellar flare
  6. GRB 250128B: TNG optical upper limit
  7. GRB 250128B: VLT/FORS2 optical observations
  8. GRB 250129A: REM optical/NIR afterglow detection
  9. GRB 250128B: OHP/T193 optical upper limit
  10. GRB 250129A: NOT optical observations and redshift confirmation
  11. GRB 250129A: VLT/X-shooter redshift of z = 2.151
  12. Swift GRB 250129A: Global MASTER-Net observations report
  13. Fermi GRB 250128B: Global MASTER-Net observations report
  14. GRB 250129A: Swift detection of a burst with an optical counterpart
  15. Swift GRB 250129A: Global MASTER-Net OT detection
  16. GRB 250128B: Fermi GBM Observation
  17. Swift GRB 250128B: Global MASTER-Net observations report
  18. EP250125a: Upper limits from Swift/BAT-GUANO
  19. GRB 250128B: Swift detection of a short burst
  20. GRB 250128B: Fermi GBM Final Real-time Localization
  21. GRB 250127A: Swift-XRT observations
  22. Fermi-LAT Gamma-ray Observations of IceCube-250102A
  23. Fermi GRB 250128A: Global MASTER-Net observations report
  24. GRB 250128A: Fermi GBM Final Real-time Localization
  25. GRB 250117A: Fermi GBM Observation
  26. Fermi GRB 250127B: Global MASTER-Net observations report
  27. Fermi-LAT Gamma-ray Observations of IceCube-250101A
  28. GRB 250127B: Fermi GBM Final Real-time Localization
  29. IPN triangulation of GRB 250119C
  30. GRB 250127A: LCO optical upper limit
  31. GRB 241223A: cubesat Avion detection
  32. GRB 250127A: SVOM detection of a long burst
  33. GRB 250126A: CALET Gamma-Ray Burst Monitor detection
  34. EP250125A: Non-detection from Fermi-GBM Observations
  35. GRB 250126A: BALROG localization (Fermi Trigger 759560335 / GRB 250126208)
  36. GRB 250126A: Fermi GBM Final Real-time Localization
  37. GECAM-A detection of a bright burst from SGR 1E1841-045
  38. GRB 250118A: Fermi GBM Observation
  39. EP250125a: REM optical counterpart detection
  40. GRB 250119C: Fermi GBM Observation
  41. EP250125a: Gemini-South optical afterglow discovery and redshift z = 2.89
  42. The EP-WXT trigger 01709130758 is a false trigger
  43. The EP-WXT trigger 01709130758 is a false trigger
  44. GRB 250121A: Swift/BAT-GUANO localization skymap of a burst
  45. IPN triangulation of a bright burst from SGR 1E1841-045
  46. GRB 250121A: CALET Gamma-Ray Burst Monitor detection
  47. Konus-Wind detection of GRB 250118B
  48. GRB 250121A: Fermi GBM Observation
  49. IPN triangulation of GRB 250118B
  50. Konus-Wind detection of GRB 250119B
  51. IPN triangulation of GRB 250119B
  52. GRB 250122A: Fermi GBM Final Real-time Localization
  53. Improved IPN triangulation of GRB 250107C
  54. GRB 250114A: Swift-BAT refined analysis
  55. GRB 250121A: Fermi-LAT detection
  56. GRB 250119C: Swift/BAT-GUANO localization skymap of a short burst
  57. GRB 250119B: Swift/BAT-GUANO localization skymap of a long burst
  58. GRB 250121A: Fermi GBM Final Real-time Localization
  59. Fermi-LAT Gamma-ray Observations of IceCube-241224A
  60. GRB 250118A: Swift/BAT-GUANO localization skymap of a short burst
  61. GRB 250119B: Fermi GBM Observation
  62. EP250108a/AT2025kg: 1.3m DFOT Optical observations
  63. Konus-Wind detection of GRB 250117A
  64. IPN triangulation of GRB 250117A (short)
  65. GRB 250119B: INTEGRAL/SPI-ACS detection
  66. LIGO/Virgo/KAGRA S250119cv: GLADEnet Completeness: Potential Host Galaxies in the 90% Credible Volume
  67. EP 250108A: Late-time optical observation by LCO
  68. LIGO/Virgo/KAGRA S250105bn: 1 counterpart neutrino candidate event from an IceCube neutrino search
  69. LIGO/Virgo/KAGRA S250119cv: Updated NED Galaxies in the Localization Volume
  70. LIGO/Virgo/KAGRA S250119cv: Updated Sky localization and EM Bright Classification
  71. GRB 250119C: Fermi GBM Final Real-time Localization
  72. LIGO/Virgo/KAGRA S250119cv: NED Galaxies in the Localization Volume
  73. GRB 250117A: Swift/BAT-GUANO localization skymap of a short burst
  74. LIGO/Virgo/KAGRA S250119cv: Identification of a GW compact binary merger candidate
  75. LIGO/Virgo/KAGRA S250119ag: Updated Sky localization
  76. GRB 250117A: GECAM observation of a short burst
  77. LIGO/Virgo/KAGRA S250118dp: Updated Sky localization
  78. GRB 250119B: BALROG localization (Fermi Trigger 758968026 / GRB 250119352)
  79. GRB 250119B: Fermi GBM Final Real-time Localization
  80. LIGO/Virgo/KAGRA S250119ag: Identification of a GW compact binary merger candidate
  81. GRB 250119A: Fermi GBM Final Real-time Localization
  82. GRB 250118A: Fermi GBM Final Real-time Localization
  83. LIGO/Virgo/KAGRA S250118dp: Identification of a GW compact binary merger candidate
  84. LIGO/Virgo/KAGRA S250118t: Updated Sky localization
  85. LIGO/Virgo/KAGRA S250118az: Identification of a GW compact binary merger candidate
  86. LIGO/Virgo/KAGRA S250118t: Identification of a GW compact binary merger candidate
  87. Konus-Wind detection of GRB 250116A
  88. GRB 250116A: INTEGRAL/SPI-ACS and PICsIT detection
  89. GRB 250116A: Fermi-LAT detection
  90. GRB 250116A: Fermi GBM Observation of an Extremely Interesting Burst
  91. GRB 250114B: Swift-XRT afterglow detection
  92. GRB 250114B: SVOM/VT upper limit
  93. LIGO/Virgo/KAGRA S250114ax: Updated NED Galaxies in the Localization Volume
  94. GRB 250101A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations and rebrightening.
  95. LIGO/Virgo/KAGRA S250114ax: Updated Sky localization
  96. Konus-Wind detection of GRB 250113A
  97. IPN triangulation of GRB 250113A
  98. GRB 250114B: Liverpool Telescope optical upper limit
  99. LIGO/Virgo/KAGRA S250114ax: GLADEnet Completeness: Potential Host Galaxies in the 90% Credible Volume
  100. GRB 250114B : MITSuME Akeno optical afterglow candidate detection

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