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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"

36273 results found.

  1. GRB 241201A: Fermi GBM Final Real-time Localization
  2. IPN triangulation of GRB 241128B
  3. Konus-Wind detection of GRB 241114B
  4. GRB 241128A: AbAO optical upper limit
  5. GRB 241128C: SVOM/GRM observation
  6. GRB 241128B: SVOM/GRM observation
  7. GRB 241128A: Swift-BAT refined analysis
  8. GRB 241127A: Swift-BAT refined analysis
  9. GRB 241127A: PRIME near-infrared detection
  10. GRB 241128A: Mondy optical observations
  11. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  12. Swift GRB 241128A: Global MASTER-Net observations report
  13. GRB 241128A: Swift-XRT refined Analysis
  14. GRB 241129A: Fermi GBM Final Real-time Localization
  15. GRB 241128A: Enhanced Swift-XRT position
  16. GRB 241128A: NOT optical observations
  17. GRB 241128A: LCO optical detection
  18. GRB 241128A: 1.5m OSN optical afterglow detection
  19. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  20. GRB 241128A: Swift-XRT afterglow detection
  21. GRB 241128A: Swift detection of a burst
  22. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  23. GRB 241127A: Swift/UVOT Detection
  24. GRB 241127A: Swift-XRT refined Analysis
  25. GRB 241127A: SVOM/GRM observation
  26. GRB 241127A: Enhanced Swift-XRT position
  27. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  28. GRB 241127A: Swift detection of a burst with an optical counterpart
  29. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  30. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  31. GRB 241126A: SVOM/GRM observation
  32. IPN triangulation of GRB 241114B
  33. GRB 241113B: EP-FXT afterglow detection
  34. Konus-Wind detection of GRB 241115D / EP 241115a
  35. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  36. GRB 241026A: radio detection with the VLA
  37. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  38. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  39. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  40. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  41. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  42. GRB 241120A: GRBAlpha detection
  43. GRB 241113B: SVOM/VT optical afterglow observations
  44. Konus-Wind detection of GRB 241117A
  45. GRB 241105A: ATCA radio detection
  46. IPN triangulation of GRB 241117A
  47. GRB 241026A: VIRT Optical Upper Limit
  48. GRB 241025A: VIRT Optical Upper Limit
  49. Konus-Wind detection of GRB 241120A
  50. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  51. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  52. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  53. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  54. GRB 241120A: Mondy and AbAO optical observations
  55. GRB 241113A: Possible ATCA Radio detection
  56. GRB 241120A: Fermi GBM Observation
  57. GRB 241114B: Insight-HXMT/HE detection
  58. GRB241120A: a long GRB detected by INTEGRAL
  59. GRB 241120A: Fermi GBM Final Real-time Localization
  60. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 241112B: Mephisto further optical observations
  62. GRB 241119A: Fermi GBM Final Real-time Localization
  63. GRB 241030A: J-band observations
  64. GRB 241115a: PRIME near-infrared upper limits
  65. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  66. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  67. GRB 241115B: Fermi GBM Observation
  68. Fermi GRB 241118A: Global MASTER-Net observations report
  69. GRB 241118A: Fermi GBM Final Real-time Localization
  70. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  71. GRB 241117A: Fermi GBM Detection
  72. Fermi GRB 241117B: Global MASTER-Net observations report
  73. GRB 241117B: Fermi GBM Final Real-time Localization
  74. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  75. Fermi GRB 241117A: Global MASTER-Net observations report
  76. GRB 241117A: Fermi GBM Final Real-time Localization
  77. GRB 241115C: Fermi GBM Observation
  78. GRB 241115A: Swift-XRT afterglow detection
  79. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  80. GRB 241115A: Mephisto upper limits
  81. GRB 241113B: Mephisto upper limits
  82. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  83. GRB 241115D / EP 241115a: SVOM/GRM observation
  84. GRB 241115A: Fermi GBM Observation
  85. GRB 241115A: LCOGT Optical Upper Limits
  86. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  87. Fermi GRB 241115B: Global MASTER-Net observations report
  88. GRB 241115B: Fermi GBM Final Real-time Localization
  89. EP241113a: No Detection in Fermi-GBM Observations
  90. Swift GRB 241115A: Global MASTER-Net observations report
  91. Fermi GRB 241115A: Global MASTER-Net observations report
  92. GRB 241115A: Swift detection of a burst
  93. GRB 241115A: Fermi GBM Final Real-time Localization
  94. GRB 241113B: KAIT Optical Afterglow Candidate
  95. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  96. GRB 241113A: Swift-BAT refined analysis
  97. GRB 241113A: PRIME near-infrared upper limits
  98. Fermi GRB 241114A: Global MASTER-Net observations report
  99. GRB 241114A: Fermi GBM Final Real-time Localization
  100. GRB 241113B: J-band upper limit from WINTER

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