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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').
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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"

21525 results found.

  1. GRB 241128A: Swift/UVOT Upper Limits
  2. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  3. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  4. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  5. GRB 241128A: Swift-BAT refined analysis
  6. GRB 241127A: Swift-BAT refined analysis
  7. GRB 241127A: PRIME near-infrared detection
  8. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  9. Swift-XRT observations of IceCube -241127A
  10. Swift GRB 241128A: Global MASTER-Net observations report
  11. GRB 241128A: Swift-XRT refined Analysis
  12. GRB 241128A: Enhanced Swift-XRT position
  13. GRB 241128A: 1.5m OSN optical afterglow detection
  14. GRB 241128A: Swift-XRT afterglow detection
  15. GRB 241128A: Swift detection of a burst
  16. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  17. GRB 241127A: Swift/UVOT Detection
  18. GRB 241127A: Swift-XRT refined Analysis
  19. GRB 241127A: SVOM/GRM observation
  20. GRB 241127A: Enhanced Swift-XRT position
  21. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  22. Swift GRB241127.91: Global MASTER-Net OT detection
  23. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  24. GRB 241127A: Swift detection of a burst with an optical counterpart
  25. Swift GRB241127.91: Global MASTER-Net observations report
  26. Swift GRB241127.91: Global MASTER-Net OT detection
  27. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  28. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  29. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  30. IPN triangulation of GRB 241114B
  31. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  32. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  33. Trigger_18947: Swift ToO observations (retracted)
  34. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  35. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  36. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  37. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  38. EP241125a: EP detection of an X-ray transient
  39. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  40. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  41. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  42. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  43. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  44. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  45. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  46. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  47. Konus-Wind detection of GRB 241117A
  48. IPN triangulation of GRB 241117A
  49. GRB 241026A: VIRT Optical Upper Limit
  50. GRB 241025A: VIRT Optical Upper Limit
  51. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 241115a: PRIME near-infrared upper limits
  53. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  54. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  55. GRB 241115B: Fermi GBM Observation
  56. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  57. GRB 241115C: Fermi GBM Observation
  58. GRB 241115A: Swift-XRT afterglow detection
  59. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  60. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  61. EP241113a: Swift XRT weak detection
  62. GRB 241115A: Fermi GBM Observation
  63. GRB 241115A: LCOGT Optical Upper Limits
  64. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  65. Swift GRB 241115A: Global MASTER-Net observations report
  66. GRB 241115A: Swift detection of a burst
  67. GRB 241113A: Swift-BAT refined analysis
  68. GRB 241113A: PRIME near-infrared upper limits
  69. GRB 241113A: J-band observations with WINTER
  70. GRB 241113B: Swift-XRT observations
  71. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  72. GRB 241113A: KAIT optical observations
  73. GRB 241113A: Swift-XRT refined Analysis
  74. GRB 241113A: Swift/UVOT Detection
  75. GRB 241113A: REM detection of the optical/NIR afterglow
  76. Konus-Wind detection of GRB 241107A (short/hard)
  77. GRB 241113B: Swift ToO observations
  78. GRB 241113A: LCO optical observations
  79. GRB 241113A: Enhanced Swift-XRT position
  80. GRB241113A: LCOGT (40-cm) optical counterpart detection
  81. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  82. GRB 241113A: Swift detection of a burst with an optical counterpart
  83. Swift GRB241113.33: Global MASTER-Net observations report
  84. GRB 241107A: GROWTH-India telescope optical upper limit
  85. GRB 241112B: Swift-XRT afterglow detection
  86. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  87. GRB 241112B: Swift ToO observations
  88. GRB 241107A: INTEGRAL IBIS localization
  89. IPN triangulation of GRB 241107A (short/hard)
  90. GRB 241025A: VZLUSAT-2 detection
  91. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  92. GRB 241108A: Swift-XRT observations
  93. GRB 241108A: Swift ToO observations
  94. GRB 241030A: TESS observations
  95. GRB 241105A: EP-FXT follow-up observations
  96. GRB 241105A: SVOM/GRM observation
  97. GRB 241105a: PRIME near-infrared upper limits
  98. GRB 241105A: Swift/UVOT Detection
  99. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  100. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory

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