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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"

19662 results found.

  1. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  2. GRB 241209A: GRANDMA/TAROT upper limit
  3. Swift GRB 241209D: Global MASTER-Net observations report
  4. GRB 241209B: Swift ToO observations
  5. GRB 241209A: REM optical/NIR observations
  6. GRB 241209D: Enhanced Swift-XRT position
  7. GRB 241209D: Swift detection of a burst
  8. GRB 241209A: Enhanced Swift-XRT position
  9. GRB 241209A: GOTO optical upper limits
  10. GRB 241209A: Prompt enhanced Swift-XRT position
  11. GRB 241209A: Swift detection of a short burst
  12. Swift GRB241209.23: Global MASTER-Net observations report
  13. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  14. GRB 241206A: DDOTI Upper Limit on the Afterglow
  15. GRB 241207C: Tiled Swift observations
  16. GRB 241206A: Fermi GBM observation
  17. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  18. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  19. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  20. GRB 241128A: Swift/UVOT Upper Limits
  21. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  22. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  23. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  24. GRB 241128A: Swift-BAT refined analysis
  25. GRB 241127A: Swift-BAT refined analysis
  26. GRB 241127A: PRIME near-infrared detection
  27. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  28. Swift-XRT observations of IceCube -241127A
  29. Swift GRB 241128A: Global MASTER-Net observations report
  30. GRB 241128A: Swift-XRT refined Analysis
  31. GRB 241128A: Enhanced Swift-XRT position
  32. GRB 241128A: 1.5m OSN optical afterglow detection
  33. GRB 241128A: Swift-XRT afterglow detection
  34. GRB 241128A: Swift detection of a burst
  35. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  36. GRB 241127A: Swift/UVOT Detection
  37. GRB 241127A: Swift-XRT refined Analysis
  38. GRB 241127A: SVOM/GRM observation
  39. GRB 241127A: Enhanced Swift-XRT position
  40. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  41. Swift GRB241127.91: Global MASTER-Net OT detection
  42. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  43. GRB 241127A: Swift detection of a burst with an optical counterpart
  44. Swift GRB241127.91: Global MASTER-Net observations report
  45. Swift GRB241127.91: Global MASTER-Net OT detection
  46. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  47. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  48. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  49. IPN triangulation of GRB 241114B
  50. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  51. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  52. Trigger_18947: Swift ToO observations (retracted)
  53. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  54. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  55. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  56. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  57. EP241125a: EP detection of an X-ray transient
  58. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  59. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  60. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  61. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  62. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  63. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  64. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  65. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  66. Konus-Wind detection of GRB 241117A
  67. IPN triangulation of GRB 241117A
  68. GRB 241025A: VIRT Optical Upper Limit
  69. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  70. GRB 241115a: PRIME near-infrared upper limits
  71. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  72. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  73. GRB 241115B: Fermi GBM Observation
  74. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  75. GRB 241115C: Fermi GBM Observation
  76. GRB 241115A: Swift-XRT afterglow detection
  77. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  78. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  79. EP241113a: Swift XRT weak detection
  80. GRB 241115A: Fermi GBM Observation
  81. GRB 241115A: LCOGT Optical Upper Limits
  82. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  83. Swift GRB 241115A: Global MASTER-Net observations report
  84. GRB 241115A: Swift detection of a burst
  85. GRB 241113A: Swift-BAT refined analysis
  86. GRB 241113A: PRIME near-infrared upper limits
  87. GRB 241113A: J-band observations with WINTER
  88. GRB 241113B: Swift-XRT observations
  89. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  90. GRB 241113A: KAIT optical observations
  91. GRB 241113A: Swift-XRT refined Analysis
  92. GRB 241113A: Swift/UVOT Detection
  93. GRB 241113A: REM detection of the optical/NIR afterglow
  94. Konus-Wind detection of GRB 241107A (short/hard)
  95. GRB 241113B: Swift ToO observations
  96. GRB 241113A: LCO optical observations
  97. GRB 241113A: Enhanced Swift-XRT position
  98. GRB241113A: LCOGT (40-cm) optical counterpart detection
  99. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  100. GRB 241113A: Swift detection of a burst with an optical counterpart

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