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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"

36398 results found.

  1. GRB 241127A: Swift-BAT refined analysis
  2. GRB 241127A: PRIME near-infrared detection
  3. GRB 241128A: Mondy optical observations
  4. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  5. Swift GRB 241128A: Global MASTER-Net observations report
  6. GRB 241128A: Swift-XRT refined Analysis
  7. GRB 241129A: Fermi GBM Final Real-time Localization
  8. GRB 241128A: Enhanced Swift-XRT position
  9. GRB 241128A: NOT optical observations
  10. GRB 241128A: LCO optical detection
  11. GRB 241128A: 1.5m OSN optical afterglow detection
  12. GRB 241128A: Swift-XRT afterglow detection
  13. GRB 241128A: Swift detection of a burst
  14. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  15. GRB 241127A: Swift/UVOT Detection
  16. GRB 241127A: Swift-XRT refined Analysis
  17. GRB 241127A: SVOM/GRM observation
  18. GRB 241127A: Enhanced Swift-XRT position
  19. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  20. GRB 241127A: Swift detection of a burst with an optical counterpart
  21. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  22. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  23. GRB 241126A: SVOM/GRM observation
  24. IPN triangulation of GRB 241114B
  25. GRB 241113B: EP-FXT afterglow detection
  26. Konus-Wind detection of GRB 241115D / EP 241115a
  27. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  28. GRB 241026A: radio detection with the VLA
  29. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  30. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  31. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  32. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  33. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  34. GRB 241120A: GRBAlpha detection
  35. GRB 241113B: SVOM/VT optical afterglow observations
  36. Konus-Wind detection of GRB 241117A
  37. GRB 241105A: ATCA radio detection
  38. IPN triangulation of GRB 241117A
  39. GRB 241026A: VIRT Optical Upper Limit
  40. GRB 241025A: VIRT Optical Upper Limit
  41. Konus-Wind detection of GRB 241120A
  42. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  43. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  44. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  45. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  46. GRB 241120A: Mondy and AbAO optical observations
  47. GRB 241113A: Possible ATCA Radio detection
  48. GRB 241120A: Fermi GBM Observation
  49. GRB 241114B: Insight-HXMT/HE detection
  50. GRB241120A: a long GRB detected by INTEGRAL
  51. GRB 241120A: Fermi GBM Final Real-time Localization
  52. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  53. GRB 241112B: Mephisto further optical observations
  54. GRB 241119A: Fermi GBM Final Real-time Localization
  55. GRB 241030A: J-band observations
  56. GRB 241115a: PRIME near-infrared upper limits
  57. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  58. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  59. GRB 241115B: Fermi GBM Observation
  60. Fermi GRB 241118A: Global MASTER-Net observations report
  61. GRB 241118A: Fermi GBM Final Real-time Localization
  62. Updates to IceCube realtime alert system for muon tracks
  63. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  64. GRB 241117A: Fermi GBM Detection
  65. Fermi GRB 241117B: Global MASTER-Net observations report
  66. GRB 241117B: Fermi GBM Final Real-time Localization
  67. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  68. Fermi GRB 241117A: Global MASTER-Net observations report
  69. GRB 241117A: Fermi GBM Final Real-time Localization
  70. GRB 241115C: Fermi GBM Observation
  71. GRB 241115A: Swift-XRT afterglow detection
  72. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  73. GRB 241115A: Mephisto upper limits
  74. GRB 241113B: Mephisto upper limits
  75. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  76. GRB 241115D / EP 241115a: SVOM/GRM observation
  77. GRB 241115A: Fermi GBM Observation
  78. GRB 241115A: LCOGT Optical Upper Limits
  79. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  80. Fermi GRB 241115B: Global MASTER-Net observations report
  81. GRB 241115B: Fermi GBM Final Real-time Localization
  82. EP241113a: No Detection in Fermi-GBM Observations
  83. Swift GRB 241115A: Global MASTER-Net observations report
  84. Fermi GRB 241115A: Global MASTER-Net observations report
  85. GRB 241115A: Swift detection of a burst
  86. GRB 241115A: Fermi GBM Final Real-time Localization
  87. GRB 241113B: KAIT Optical Afterglow Candidate
  88. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  89. GRB 241113A: Swift-BAT refined analysis
  90. GRB 241113A: PRIME near-infrared upper limits
  91. Fermi GRB 241114A: Global MASTER-Net observations report
  92. GRB 241114A: Fermi GBM Final Real-time Localization
  93. GRB 241113B: J-band upper limit from WINTER
  94. GRB 241113A: J-band observations with WINTER
  95. GRB 241030A: LCO optical observation
  96. GRB 241113B: Swift-XRT observations
  97. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  98. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  99. GRB 241113A: KAIT optical observations
  100. EP241113b/GRB 241113B: EP detection of GRB 241113B

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