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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"

28299 results found.

  1. EP241202b: Upper limits from Fermi-GBM Observations
  2. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  3. EP241202b: Kinder optical counterpart candidate
  4. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  5. GRB 241113B : RAPAS follow-up observation
  6. Konus-Wind detection of GRB 241130A
  7. EP241201a: BOOTES-5 optical upper limit
  8. EP241202b: EP detection of a fast X-ray transient
  9. EP241201a: NOT optical observations
  10. IPN triangulation of GRB 241130A
  11. GRB 241130A: EIRSAT-1 GMOD Detection
  12. GRB 241128A: Swift/UVOT Upper Limits
  13. GRB 241130A: Fermi GBM Detection
  14. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  15. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  16. EP241201a: Kinder optical counterpart candidate
  17. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  18. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  19. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  20. EP241126a: 1.6m Mephisto Optical Upper Limits
  21. GRB 241201A: Fermi GBM Final Real-time Localization
  22. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  23. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  24. Fermi trigger No 754701230: Global MASTER-Net observations report
  25. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  26. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  27. GRB 241128A: AbAO optical upper limit
  28. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  29. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  31. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  32. GRB 241128A: Swift-BAT refined analysis
  33. GRB 241127A: Swift-BAT refined analysis
  34. GRB 241127A: PRIME near-infrared detection
  35. GRB 241128A: Mondy optical observations
  36. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  37. Swift-XRT observations of IceCube -241127A
  38. Fermi-LAT gamma-ray observations of IceCube-241127A
  39. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  40. GRB 241128A: Swift-XRT refined Analysis
  41. GRB 241128A: Enhanced Swift-XRT position
  42. GRB 241128A: NOT optical observations
  43. GRB 241128A: LCO optical detection
  44. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  45. GRB 241128A: Swift-XRT afterglow detection
  46. GRB 241128A: Swift detection of a burst
  47. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  48. GRB 241127A: Swift/UVOT Detection
  49. GRB 241127A: Swift-XRT refined Analysis
  50. GRB 241127A: Enhanced Swift-XRT position
  51. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  52. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  53. Swift GRB241127.91: Global MASTER-Net OT detection
  54. EP241126a: WFST Observations
  55. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  56. GRB 241127A: Swift detection of a burst with an optical counterpart
  57. Swift GRB241127.91: Global MASTER-Net OT detection
  58. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  59. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  60. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  61. EP241126a: Optical Upper limits with Kinder observations
  62. IPN triangulation of GRB 241114B
  63. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  64. EP241126a: GSP detects optical counterpart
  65. EP241126a: TRT optical counterpart detection
  66. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  67. EP241126a: EP detection of a fast X-ray transient
  68. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  69. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  70. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  71. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  72. GECAM detection of a short burst from SGR 1830
  73. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  74. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  75. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  76. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  77. GRB 241026A: radio detection with the VLA
  78. EP241125a: Optical upper limit with Kinder observations
  79. EP241125a: EP detection of an X-ray transient
  80. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  81. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  82. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  83. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  84. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  85. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  86. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  87. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  88. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  89. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  90. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  92. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  93. IPN triangulation of GRB 241117A
  94. GRB 241026A: VIRT Optical Upper Limit
  95. GRB 241025A: VIRT Optical Upper Limit
  96. GRB241120A: OHP/T193 optical observations
  97. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  98. GRB 241120A: Mondy and AbAO optical observations
  99. EP241119a: Optical upper limits with Kinder observations
  100. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event

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