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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"

36364 results found.

  1. GRB 241209A: VLT/X-shooter spectroscopy
  2. GRB 241209A: Enhanced Swift-XRT position
  3. GRB 241114B: cubesat Avion detection
  4. GRB 241209A: VLT optical observations
  5. Fermi GRB 241209A: Global MASTER-Net observations report
  6. GRB 241209C: Fermi GBM Final Real-time Localization
  7. GRB 241209A: GOTO optical upper limits
  8. GRB 241209A: Prompt enhanced Swift-XRT position
  9. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  10. GRB 241209A: Swift detection of a short burst
  11. GRB 241209A: Fermi GBM Final Real-time Localization
  12. Fermi GRB 241207B: Global MASTER-Net observations report
  13. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  14. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  15. GRB 241201A: AstroSat CZTI detection
  16. GRB 241206A: DDOTI Upper Limit on the Afterglow
  17. GRB 241207C: MASTER optical observations
  18. GRB 241207C: Tiled Swift observations
  19. GRB 241207C: MAXI/GSC detection
  20. GRB 241207B: Fermi GBM Final Real-time Localization
  21. Fermi GRB 241207A: Global MASTER-Net observations report
  22. GRB 241206A: Fermi GBM observation
  23. GRB 241206C: SVOM/GRM observation of a likely short burst
  24. GRB 241207A: Fermi GBM Final Real-time Localization
  25. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  26. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  27. GRB 241206B: GWAC-F50A optical upper limit
  28. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  29. Fermi GRB 241206A: Global MASTER-Net observations report
  30. GRB 241206A: Fermi GBM Final Real-time Localization
  31. GRB 241204A: COLIBRÍ Optical Upper Limit
  32. EP241202b: KAIT optical upper limit
  33. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  34. GRB 241204A: DDOTI Upper Limits on the Afterglow
  35. GRB 241204A: Fermi GBM Observation
  36. Fermi GRB 241204A: Global MASTER-Net observations report
  37. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 241128A : RAPAS follow-up observations
  39. GRB 241201A: GRBAlpha detection
  40. GRB 241204A: Fermi-LAT detection
  41. EP241202b: Upper limits from Fermi-GBM Observations
  42. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  43. GRB 241113B : RAPAS follow-up observation
  44. Konus-Wind detection of GRB 241130A
  45. EP241201a: BOOTES-5 optical upper limit
  46. IPN triangulation of GRB 241130A
  47. GRB 241130A: EIRSAT-1 GMOD Detection
  48. GRB 241128A: Swift/UVOT Upper Limits
  49. GRB 241130A: Fermi GBM Detection
  50. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  51. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  52. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  53. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  54. GRB241201B: Fermi GBM Final Localization
  55. GRB241201B: Fermi GBM Final Localization
  56. Fermi GRB 241201A: Global MASTER-Net observations report
  57. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  58. GRB 241130A: Fermi GBM Final Real-time Localization
  59. GRB 241130A: Fermi GBM Final Real-time Localization
  60. GRB 241201A: Fermi GBM Final Real-time Localization
  61. IPN triangulation of GRB 241128B
  62. Konus-Wind detection of GRB 241114B
  63. GRB 241128A: AbAO optical upper limit
  64. GRB 241128C: SVOM/GRM observation
  65. GRB 241128B: SVOM/GRM observation
  66. GRB 241128A: Swift-BAT refined analysis
  67. GRB 241127A: Swift-BAT refined analysis
  68. GRB 241127A: PRIME near-infrared detection
  69. GRB 241128A: Mondy optical observations
  70. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  71. Swift GRB 241128A: Global MASTER-Net observations report
  72. GRB 241128A: Swift-XRT refined Analysis
  73. GRB 241129A: Fermi GBM Final Real-time Localization
  74. GRB 241128A: Enhanced Swift-XRT position
  75. GRB 241128A: NOT optical observations
  76. GRB 241128A: LCO optical detection
  77. GRB 241128A: 1.5m OSN optical afterglow detection
  78. GRB 241128A: Swift-XRT afterglow detection
  79. GRB 241128A: Swift detection of a burst
  80. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  81. GRB 241127A: Swift/UVOT Detection
  82. GRB 241127A: Swift-XRT refined Analysis
  83. GRB 241127A: SVOM/GRM observation
  84. GRB 241127A: Enhanced Swift-XRT position
  85. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  86. GRB 241127A: Swift detection of a burst with an optical counterpart
  87. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  88. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  89. GRB 241126A: SVOM/GRM observation
  90. IPN triangulation of GRB 241114B
  91. GRB 241113B: EP-FXT afterglow detection
  92. Konus-Wind detection of GRB 241115D / EP 241115a
  93. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  94. GRB 241026A: radio detection with the VLA
  95. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  96. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  97. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  98. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  99. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  100. GRB 241120A: GRBAlpha detection

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