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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"

36274 results found.

  1. GRB 241212A: SVOM detection of a bright long burst
  2. GRB 241212A: Fermi GBM Final Real-time Localization
  3. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  4. GRB 241209A: Chandra X-ray Detection
  5. Konus-Wind detection of GRB 241209B
  6. GRB 241207A: EIRSAT-1 GMOD Detection
  7. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  8. GRB 241209B: GRBAlpha detection
  9. GRB 241206C: GRBAlpha detection
  10. GRB 241211A: Fermi GBM Final Real-time Localization
  11. GRB 241129A: Fermi GBM Observation
  12. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  13. GRB 241209D: REM optical/NIR upper limits
  14. Konus-Wind detection of GRB 241209D
  15. GRB 241209B: Swift-XRT afterglow detection
  16. GRB 241209C: Fermi GBM Observation
  17. GRB 241209A: Swift-XRT refined Analysis
  18. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  19. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  20. GRB 241209D: AstroSat CZTI detection
  21. GRB 241209A: EP-FXT follow-up observations
  22. GRB 241209B: SVOM/VT afterglow detection
  23. GRB 241207B: Fermi GBM Observation
  24. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  25. GRB 241209D: Swift-XRT refined Analysis
  26. GRB 241209D: Fermi GBM Observation
  27. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  28. GRB 241209D: COLIBRÍ detection of the afterglow
  29. GRB 241209A: COLIBRÍ Optical Upper Limit
  30. Fermi GRB 241209D: Global MASTER-Net observations report
  31. GRB 241209A: Fermi GBM Observation
  32. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  33. GRB 241209A: GRANDMA/TAROT upper limit
  34. GRB 241209B: BOOTES-5 optical upper limit
  35. Swift GRB 241209D: Global MASTER-Net observations report
  36. Fermi GRB 241209C: Global MASTER-Net observations report
  37. Fermi GRB 241209E: Global MASTER-Net observations report
  38. GRB 241209E: Fermi GBM Final Real-time Localization
  39. GRB 241209B: Swift ToO observations
  40. GRB 241209A: REM optical/NIR observations
  41. GRB 241209D: Enhanced Swift-XRT position
  42. GRB 241209C: AstroSat CZTI detection
  43. GRB 241209D: Swift detection of a burst
  44. GRB 241209D: Fermi GBM Final Real-time Localization
  45. GRB 241209A: VLT/X-shooter spectroscopy
  46. GRB 241209A: Enhanced Swift-XRT position
  47. GRB 241114B: cubesat Avion detection
  48. GRB 241209A: VLT optical observations
  49. Fermi GRB 241209A: Global MASTER-Net observations report
  50. GRB 241209C: Fermi GBM Final Real-time Localization
  51. GRB 241209A: GOTO optical upper limits
  52. GRB 241209A: Prompt enhanced Swift-XRT position
  53. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  54. GRB 241209A: Swift detection of a short burst
  55. GRB 241209A: Fermi GBM Final Real-time Localization
  56. Fermi GRB 241207B: Global MASTER-Net observations report
  57. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  58. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  59. GRB 241201A: AstroSat CZTI detection
  60. GRB 241206A: DDOTI Upper Limit on the Afterglow
  61. GRB 241207C: MASTER optical observations
  62. GRB 241207C: Tiled Swift observations
  63. GRB 241207C: MAXI/GSC detection
  64. GRB 241207B: Fermi GBM Final Real-time Localization
  65. Fermi GRB 241207A: Global MASTER-Net observations report
  66. GRB 241206A: Fermi GBM observation
  67. GRB 241206C: SVOM/GRM observation of a likely short burst
  68. GRB 241207A: Fermi GBM Final Real-time Localization
  69. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  70. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  71. GRB 241206B: GWAC-F50A optical upper limit
  72. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  73. Fermi GRB 241206A: Global MASTER-Net observations report
  74. GRB 241206A: Fermi GBM Final Real-time Localization
  75. GRB 241204A: COLIBRÍ Optical Upper Limit
  76. EP241202b: KAIT optical upper limit
  77. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  78. GRB 241204A: DDOTI Upper Limits on the Afterglow
  79. GRB 241204A: Fermi GBM Observation
  80. Fermi GRB 241204A: Global MASTER-Net observations report
  81. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  82. GRB 241128A : RAPAS follow-up observations
  83. GRB 241201A: GRBAlpha detection
  84. GRB 241204A: Fermi-LAT detection
  85. EP241202b: Upper limits from Fermi-GBM Observations
  86. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  87. GRB 241113B : RAPAS follow-up observation
  88. Konus-Wind detection of GRB 241130A
  89. IPN triangulation of GRB 241130A
  90. GRB 241130A: EIRSAT-1 GMOD Detection
  91. GRB 241128A: Swift/UVOT Upper Limits
  92. GRB 241130A: Fermi GBM Detection
  93. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  94. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  95. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  96. GRB241201B: Fermi GBM Final Localization
  97. GRB241201B: Fermi GBM Final Localization
  98. Fermi GRB 241201A: Global MASTER-Net observations report
  99. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  100. GRB 241130A: Fermi GBM Final Real-time Localization

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