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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"

45815 results found.

  1. GRB 241204A: Fermi-LAT detection
  2. EP241202b: Upper limits from Fermi-GBM Observations
  3. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  4. EP241202b: Kinder optical counterpart candidate
  5. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  6. GRB 241113B : RAPAS follow-up observation
  7. EP241201a: EP-FXT follow-up observations
  8. Konus-Wind detection of GRB 241130A
  9. EP241202b: Global MASTER-Net observations report
  10. EP241201a: BOOTES-5 optical upper limit
  11. EP241202b: EP detection of a fast X-ray transient
  12. EP241201a: NOT optical observations
  13. IPN triangulation of GRB 241130A
  14. GRB 241130A: EIRSAT-1 GMOD Detection
  15. GRB 241128A: Swift/UVOT Upper Limits
  16. GRB 241130A: Fermi GBM Detection
  17. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  18. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  19. EP241201a: Kinder optical counterpart candidate
  20. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  21. EP241201a: Global MASTER-Net observations report
  22. EP241201a: EP detection of a fast X-ray transient
  23. The EP-WXT trigger 01709126243 is not a real source
  24. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  25. GRB241201B: Fermi GBM Final Localization
  26. GRB241201B: Fermi GBM Final Localization
  27. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  28. EP241126a: SOAR observations of the optical counterpart
  29. Fermi GRB 241201A: Global MASTER-Net observations report
  30. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  31. GRB 241130A: Fermi GBM Final Real-time Localization
  32. GRB 241130A: Fermi GBM Final Real-time Localization
  33. EP241126a: 1.6m Mephisto Optical Upper Limits
  34. GRB 241201A: Fermi GBM Final Real-time Localization
  35. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  36. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  37. Fermi trigger No 754701230: Global MASTER-Net observations report
  38. IPN triangulation of GRB 241128B
  39. Konus-Wind detection of GRB 241114B
  40. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  41. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  42. GRB 241128A: AbAO optical upper limit
  43. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  44. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  45. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  46. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  47. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  48. GRB 241128C: SVOM/GRM observation
  49. GRB 241128B: SVOM/GRM observation
  50. GRB 241128A: Swift-BAT refined analysis
  51. GRB 241127A: Swift-BAT refined analysis
  52. EP241126a: NOT optical observations
  53. GRB 241127A: PRIME near-infrared detection
  54. GRB 241128A: Mondy optical observations
  55. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  56. Swift-XRT observations of IceCube -241127A
  57. Swift GRB 241128A: Global MASTER-Net observations report
  58. Fermi-LAT gamma-ray observations of IceCube-241127A
  59. EP241126a: SVOM/VT observations
  60. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  61. GRB 241128A: Swift-XRT refined Analysis
  62. GRB 241129A: Fermi GBM Final Real-time Localization
  63. GRB 241128A: Enhanced Swift-XRT position
  64. GRB 241128A: NOT optical observations
  65. GRB 241128A: LCO optical detection
  66. GRB 241128A: 1.5m OSN optical afterglow detection
  67. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  68. Fermi trigger No 754492985: Global MASTER-Net observations report
  69. GRB 241128A: Swift-XRT afterglow detection
  70. GRB 241128A: Swift detection of a burst
  71. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  72. GRB 241127A: Swift/UVOT Detection
  73. GRB 241127A: Swift-XRT refined Analysis
  74. GRB 241127A: SVOM/GRM observation
  75. GRB 241127A: Enhanced Swift-XRT position
  76. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  77. The EP-WXT trigger 01709125191 is not a real source
  78. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  79. Swift GRB241127.91: Global MASTER-Net OT detection
  80. EP241126a: WFST Observations
  81. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  82. IceCube Alert 241127.59: Global MASTER-Net observations report
  83. GRB 241127A: Swift detection of a burst with an optical counterpart
  84. Swift GRB241127.91: Global MASTER-Net observations report
  85. Swift GRB241127.91: Global MASTER-Net OT detection
  86. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  87. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  88. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  89. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  90. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  91. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  92. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  93. EP241126a: Optical Upper limits with Kinder observations
  94. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  95. GRB 241126A: SVOM/GRM observation
  96. IPN triangulation of GRB 241114B
  97. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  98. EP241126a: EP-FXT follow-up observation update
  99. EP241126a: GSP detects optical counterpart
  100. EP241126a: TRT optical counterpart detection

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