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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"

43136 results found.

  1. EP241202b: EP detection of a fast X-ray transient
  2. EP241201a: NOT optical observations
  3. IPN triangulation of GRB 241130A
  4. GRB 241130A: EIRSAT-1 GMOD Detection
  5. GRB 241128A: Swift/UVOT Upper Limits
  6. GRB 241130A: Fermi GBM Detection
  7. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  8. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  9. EP241201a: Kinder optical counterpart candidate
  10. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  11. EP241201a: Global MASTER-Net observations report
  12. EP241201a: EP detection of a fast X-ray transient
  13. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  14. GRB241201B: Fermi GBM Final Localization
  15. GRB241201B: Fermi GBM Final Localization
  16. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  17. EP241126a: SOAR observations of the optical counterpart
  18. Fermi GRB 241201A: Global MASTER-Net observations report
  19. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  20. GRB 241130A: Fermi GBM Final Real-time Localization
  21. GRB 241130A: Fermi GBM Final Real-time Localization
  22. EP241126a: 1.6m Mephisto Optical Upper Limits
  23. GRB 241201A: Fermi GBM Final Real-time Localization
  24. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  26. Fermi trigger No 754701230: Global MASTER-Net observations report
  27. IPN triangulation of GRB 241128B
  28. Konus-Wind detection of GRB 241114B
  29. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  30. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  31. GRB 241128A: AbAO optical upper limit
  32. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  33. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  34. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  35. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  36. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  37. GRB 241128C: SVOM/GRM observation
  38. GRB 241128B: SVOM/GRM observation
  39. GRB 241128A: Swift-BAT refined analysis
  40. GRB 241127A: Swift-BAT refined analysis
  41. EP241126a: NOT optical observations
  42. GRB 241127A: PRIME near-infrared detection
  43. GRB 241128A: Mondy optical observations
  44. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  45. Swift-XRT observations of IceCube -241127A
  46. Swift GRB 241128A: Global MASTER-Net observations report
  47. Fermi-LAT gamma-ray observations of IceCube-241127A
  48. EP241126a: SVOM/VT observations
  49. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  50. GRB 241128A: Swift-XRT refined Analysis
  51. GRB 241129A: Fermi GBM Final Real-time Localization
  52. GRB 241128A: Enhanced Swift-XRT position
  53. GRB 241128A: NOT optical observations
  54. GRB 241128A: LCO optical detection
  55. GRB 241128A: 1.5m OSN optical afterglow detection
  56. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  57. Fermi trigger No 754492985: Global MASTER-Net observations report
  58. GRB 241128A: Swift detection of a burst
  59. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  60. GRB 241127A: Swift/UVOT Detection
  61. GRB 241127A: Swift-XRT refined Analysis
  62. GRB 241127A: SVOM/GRM observation
  63. GRB 241127A: Enhanced Swift-XRT position
  64. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  65. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  66. Swift GRB241127.91: Global MASTER-Net OT detection
  67. EP241126a: WFST Observations
  68. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  69. IceCube Alert 241127.59: Global MASTER-Net observations report
  70. GRB 241127A: Swift detection of a burst with an optical counterpart
  71. Swift GRB241127.91: Global MASTER-Net observations report
  72. Swift GRB241127.91: Global MASTER-Net OT detection
  73. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  74. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  75. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  76. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  77. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  78. EP241126a: Optical Upper limits with Kinder observations
  79. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  80. GRB 241126A: SVOM/GRM observation
  81. IPN triangulation of GRB 241114B
  82. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  83. EP241126a: EP-FXT follow-up observation update
  84. EP241126a: GSP detects optical counterpart
  85. EP241126a: TRT optical counterpart detection
  86. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  87. EP241126a: EP detection of a fast X-ray transient
  88. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  89. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  90. LIGO/Virgo/KAGRA S241126dm: Retraction of GW compact binary merger candidate
  91. GRB 241113B: EP-FXT afterglow detection
  92. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  93. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  94. SVOM/GRM detection of a short burst from SGR 1830
  95. GECAM detection of a short burst from SGR 1830
  96. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  97. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  98. Konus-Wind detection of GRB 241115D / EP 241115a
  99. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  100. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations

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