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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"

32711 results found.

  1. Fermi GRB 241204A: Global MASTER-Net observations report
  2. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  3. GRB 241128A : RAPAS follow-up observations
  4. GRB 241201A: GRBAlpha detection
  5. EP241202b: Upper limits from Fermi-GBM Observations
  6. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  7. EP241202b: Kinder optical counterpart candidate
  8. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  9. GRB 241113B : RAPAS follow-up observation
  10. EP241201a: EP-FXT follow-up observations
  11. Konus-Wind detection of GRB 241130A
  12. EP241202b: Global MASTER-Net observations report
  13. EP241201a: BOOTES-5 optical upper limit
  14. EP241201a: NOT optical observations
  15. IPN triangulation of GRB 241130A
  16. GRB 241130A: EIRSAT-1 GMOD Detection
  17. GRB 241128A: Swift/UVOT Upper Limits
  18. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  19. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  20. EP241201a: Kinder optical counterpart candidate
  21. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  22. EP241201a: Global MASTER-Net observations report
  23. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  24. EP241126a: SOAR observations of the optical counterpart
  25. Fermi GRB 241201A: Global MASTER-Net observations report
  26. EP241126a: 1.6m Mephisto Optical Upper Limits
  27. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  28. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  29. IPN triangulation of GRB 241128B
  30. Konus-Wind detection of GRB 241114B
  31. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  32. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  33. GRB 241128A: AbAO optical upper limit
  34. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  35. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  36. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  37. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  38. GRB 241128A: Swift-BAT refined analysis
  39. GRB 241127A: Swift-BAT refined analysis
  40. EP241126a: NOT optical observations
  41. GRB 241127A: PRIME near-infrared detection
  42. GRB 241128A: Mondy optical observations
  43. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  44. Swift-XRT observations of IceCube -241127A
  45. Swift GRB 241128A: Global MASTER-Net observations report
  46. Fermi-LAT gamma-ray observations of IceCube-241127A
  47. EP241126a: SVOM/VT observations
  48. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  49. GRB 241128A: NOT optical observations
  50. GRB 241128A: LCO optical detection
  51. GRB 241128A: 1.5m OSN optical afterglow detection
  52. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  53. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  54. GRB 241127A: Swift/UVOT Detection
  55. GRB 241127A: SVOM/GRM observation
  56. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  57. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  58. EP241126a: WFST Observations
  59. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  60. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  61. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  62. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  63. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  64. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  65. EP241126a: Optical Upper limits with Kinder observations
  66. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  67. IPN triangulation of GRB 241114B
  68. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  69. EP241126a: EP-FXT follow-up observation update
  70. EP241126a: GSP detects optical counterpart
  71. EP241126a: TRT optical counterpart detection
  72. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  73. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  74. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  75. Trigger_18947: Swift ToO observations (retracted)
  76. GRB 241113B: EP-FXT afterglow detection
  77. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  78. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  79. SVOM/GRM detection of a short burst from SGR 1830
  80. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  81. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  82. Konus-Wind detection of GRB 241115D / EP 241115a
  83. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  84. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  85. GRB 241026A: radio detection with the VLA
  86. EP241125a: Optical upper limit with Kinder observations
  87. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  88. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  89. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  90. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  91. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  92. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  93. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  94. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  95. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  96. GRB 241120A: GRBAlpha detection
  97. GRB 241113B: SVOM/VT optical afterglow observations
  98. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  99. Konus-Wind detection of GRB 241117A
  100. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification

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