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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"

36276 results found.

  1. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  2. GRB 241130A: Fermi GBM Final Real-time Localization
  3. GRB 241130A: Fermi GBM Final Real-time Localization
  4. GRB 241201A: Fermi GBM Final Real-time Localization
  5. IPN triangulation of GRB 241128B
  6. Konus-Wind detection of GRB 241114B
  7. GRB 241128A: AbAO optical upper limit
  8. GRB 241128C: SVOM/GRM observation
  9. GRB 241128B: SVOM/GRM observation
  10. GRB 241128A: Swift-BAT refined analysis
  11. GRB 241127A: Swift-BAT refined analysis
  12. GRB 241127A: PRIME near-infrared detection
  13. GRB 241128A: Mondy optical observations
  14. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  15. Swift GRB 241128A: Global MASTER-Net observations report
  16. GRB 241128A: Swift-XRT refined Analysis
  17. GRB 241129A: Fermi GBM Final Real-time Localization
  18. GRB 241128A: Enhanced Swift-XRT position
  19. GRB 241128A: NOT optical observations
  20. GRB 241128A: LCO optical detection
  21. GRB 241128A: 1.5m OSN optical afterglow detection
  22. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  23. GRB 241128A: Swift-XRT afterglow detection
  24. GRB 241128A: Swift detection of a burst
  25. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  26. GRB 241127A: Swift/UVOT Detection
  27. GRB 241127A: Swift-XRT refined Analysis
  28. GRB 241127A: SVOM/GRM observation
  29. GRB 241127A: Enhanced Swift-XRT position
  30. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  31. GRB 241127A: Swift detection of a burst with an optical counterpart
  32. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  33. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  34. GRB 241126A: SVOM/GRM observation
  35. IPN triangulation of GRB 241114B
  36. GRB 241113B: EP-FXT afterglow detection
  37. Konus-Wind detection of GRB 241115D / EP 241115a
  38. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  39. GRB 241026A: radio detection with the VLA
  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: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  43. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  44. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  45. GRB 241120A: GRBAlpha detection
  46. GRB 241113B: SVOM/VT optical afterglow observations
  47. Konus-Wind detection of GRB 241117A
  48. GRB 241105A: ATCA radio detection
  49. IPN triangulation of GRB 241117A
  50. GRB 241026A: VIRT Optical Upper Limit
  51. GRB 241025A: VIRT Optical Upper Limit
  52. Konus-Wind detection of GRB 241120A
  53. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  54. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  55. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  56. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  57. GRB 241120A: Mondy and AbAO optical observations
  58. GRB 241113A: Possible ATCA Radio detection
  59. GRB 241120A: Fermi GBM Observation
  60. GRB 241114B: Insight-HXMT/HE detection
  61. GRB241120A: a long GRB detected by INTEGRAL
  62. GRB 241120A: Fermi GBM Final Real-time Localization
  63. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  64. GRB 241112B: Mephisto further optical observations
  65. GRB 241119A: Fermi GBM Final Real-time Localization
  66. GRB 241030A: J-band observations
  67. GRB 241115a: PRIME near-infrared upper limits
  68. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  69. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  70. GRB 241115B: Fermi GBM Observation
  71. Fermi GRB 241118A: Global MASTER-Net observations report
  72. GRB 241118A: Fermi GBM Final Real-time Localization
  73. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  74. GRB 241117A: Fermi GBM Detection
  75. Fermi GRB 241117B: Global MASTER-Net observations report
  76. GRB 241117B: Fermi GBM Final Real-time Localization
  77. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  78. Fermi GRB 241117A: Global MASTER-Net observations report
  79. GRB 241117A: Fermi GBM Final Real-time Localization
  80. GRB 241115C: Fermi GBM Observation
  81. GRB 241115A: Swift-XRT afterglow detection
  82. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  83. GRB 241115A: Mephisto upper limits
  84. GRB 241113B: Mephisto upper limits
  85. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  86. GRB 241115D / EP 241115a: SVOM/GRM observation
  87. GRB 241115A: Fermi GBM Observation
  88. GRB 241115A: LCOGT Optical Upper Limits
  89. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  90. Fermi GRB 241115B: Global MASTER-Net observations report
  91. GRB 241115B: Fermi GBM Final Real-time Localization
  92. EP241113a: No Detection in Fermi-GBM Observations
  93. Swift GRB 241115A: Global MASTER-Net observations report
  94. Fermi GRB 241115A: Global MASTER-Net observations report
  95. GRB 241115A: Swift detection of a burst
  96. GRB 241115A: Fermi GBM Final Real-time Localization
  97. GRB 241113B: KAIT Optical Afterglow Candidate
  98. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  99. GRB 241113A: Swift-BAT refined analysis
  100. GRB 241113A: PRIME near-infrared upper limits

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