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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"

36352 results found.

  1. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  2. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  3. GRB 241201A: AstroSat CZTI detection
  4. GRB 241206A: DDOTI Upper Limit on the Afterglow
  5. GRB 241207C: MASTER optical observations
  6. GRB 241207C: Tiled Swift observations
  7. GRB 241207C: MAXI/GSC detection
  8. GRB 241207B: Fermi GBM Final Real-time Localization
  9. Fermi GRB 241207A: Global MASTER-Net observations report
  10. GRB 241206A: Fermi GBM observation
  11. GRB 241206C: SVOM/GRM observation of a likely short burst
  12. GRB 241207A: Fermi GBM Final Real-time Localization
  13. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  14. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  15. GRB 241206B: GWAC-F50A optical upper limit
  16. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  17. Fermi GRB 241206A: Global MASTER-Net observations report
  18. GRB 241206A: Fermi GBM Final Real-time Localization
  19. GRB 241204A: COLIBRÍ Optical Upper Limit
  20. EP241202b: KAIT optical upper limit
  21. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  22. GRB 241204A: DDOTI Upper Limits on the Afterglow
  23. GRB 241204A: Fermi GBM Observation
  24. Fermi GRB 241204A: Global MASTER-Net observations report
  25. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  26. GRB 241128A : RAPAS follow-up observations
  27. GRB 241201A: GRBAlpha detection
  28. GRB 241204A: Fermi-LAT detection
  29. EP241202b: Upper limits from Fermi-GBM Observations
  30. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  31. GRB 241113B : RAPAS follow-up observation
  32. Konus-Wind detection of GRB 241130A
  33. EP241201a: BOOTES-5 optical upper limit
  34. IPN triangulation of GRB 241130A
  35. GRB 241130A: EIRSAT-1 GMOD Detection
  36. GRB 241128A: Swift/UVOT Upper Limits
  37. GRB 241130A: Fermi GBM Detection
  38. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  39. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  40. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  41. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  42. GRB241201B: Fermi GBM Final Localization
  43. GRB241201B: Fermi GBM Final Localization
  44. Fermi GRB 241201A: Global MASTER-Net observations report
  45. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  46. GRB 241130A: Fermi GBM Final Real-time Localization
  47. GRB 241130A: Fermi GBM Final Real-time Localization
  48. GRB 241201A: Fermi GBM Final Real-time Localization
  49. IPN triangulation of GRB 241128B
  50. Konus-Wind detection of GRB 241114B
  51. GRB 241128A: AbAO optical upper limit
  52. GRB 241128C: SVOM/GRM observation
  53. GRB 241128B: SVOM/GRM observation
  54. GRB 241128A: Swift-BAT refined analysis
  55. GRB 241127A: Swift-BAT refined analysis
  56. GRB 241127A: PRIME near-infrared detection
  57. GRB 241128A: Mondy optical observations
  58. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  59. Swift GRB 241128A: Global MASTER-Net observations report
  60. GRB 241128A: Swift-XRT refined Analysis
  61. GRB 241129A: Fermi GBM Final Real-time Localization
  62. GRB 241128A: Enhanced Swift-XRT position
  63. GRB 241128A: NOT optical observations
  64. GRB 241128A: LCO optical detection
  65. GRB 241128A: 1.5m OSN optical afterglow detection
  66. GRB 241128A: Swift-XRT afterglow detection
  67. GRB 241128A: Swift detection of a burst
  68. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  69. GRB 241127A: Swift/UVOT Detection
  70. GRB 241127A: Swift-XRT refined Analysis
  71. GRB 241127A: SVOM/GRM observation
  72. GRB 241127A: Enhanced Swift-XRT position
  73. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  74. GRB 241127A: Swift detection of a burst with an optical counterpart
  75. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  76. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  77. GRB 241126A: SVOM/GRM observation
  78. IPN triangulation of GRB 241114B
  79. GRB 241113B: EP-FXT afterglow detection
  80. Konus-Wind detection of GRB 241115D / EP 241115a
  81. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  82. GRB 241026A: radio detection with the VLA
  83. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  84. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  85. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  86. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  87. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  88. GRB 241120A: GRBAlpha detection
  89. GRB 241113B: SVOM/VT optical afterglow observations
  90. Konus-Wind detection of GRB 241117A
  91. GRB 241105A: ATCA radio detection
  92. IPN triangulation of GRB 241117A
  93. GRB 241026A: VIRT Optical Upper Limit
  94. GRB 241025A: VIRT Optical Upper Limit
  95. Konus-Wind detection of GRB 241120A
  96. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  97. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  98. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  99. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  100. GRB 241120A: Mondy and AbAO optical observations

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