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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"

28275 results found.

  1. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  2. EP241126a: 1.6m Mephisto Optical Upper Limits
  3. GRB 241201A: Fermi GBM Final Real-time Localization
  4. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  5. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  6. Fermi trigger No 754701230: Global MASTER-Net observations report
  7. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  8. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  9. GRB 241128A: AbAO optical upper limit
  10. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  11. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  12. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  13. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  14. GRB 241128A: Swift-BAT refined analysis
  15. GRB 241127A: Swift-BAT refined analysis
  16. GRB 241127A: PRIME near-infrared detection
  17. GRB 241128A: Mondy optical observations
  18. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  19. Swift-XRT observations of IceCube -241127A
  20. Fermi-LAT gamma-ray observations of IceCube-241127A
  21. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  22. GRB 241128A: Swift-XRT refined Analysis
  23. GRB 241128A: Enhanced Swift-XRT position
  24. GRB 241128A: NOT optical observations
  25. GRB 241128A: LCO optical detection
  26. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  27. GRB 241128A: Swift-XRT afterglow detection
  28. GRB 241128A: Swift detection of a burst
  29. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  30. GRB 241127A: Swift/UVOT Detection
  31. GRB 241127A: Swift-XRT refined Analysis
  32. GRB 241127A: Enhanced Swift-XRT position
  33. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  34. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  35. Swift GRB241127.91: Global MASTER-Net OT detection
  36. EP241126a: WFST Observations
  37. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  38. GRB 241127A: Swift detection of a burst with an optical counterpart
  39. Swift GRB241127.91: Global MASTER-Net OT detection
  40. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  41. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  42. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  43. EP241126a: Optical Upper limits with Kinder observations
  44. IPN triangulation of GRB 241114B
  45. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  46. EP241126a: GSP detects optical counterpart
  47. EP241126a: TRT optical counterpart detection
  48. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  49. EP241126a: EP detection of a fast X-ray transient
  50. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  51. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  52. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  53. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  54. GECAM detection of a short burst from SGR 1830
  55. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  56. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  57. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  58. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  59. GRB 241026A: radio detection with the VLA
  60. EP241125a: Optical upper limit with Kinder observations
  61. EP241125a: EP detection of an X-ray transient
  62. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  63. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  64. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  65. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  66. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  67. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  68. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  69. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  70. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  71. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  72. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  73. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  74. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  75. IPN triangulation of GRB 241117A
  76. GRB 241026A: VIRT Optical Upper Limit
  77. GRB 241025A: VIRT Optical Upper Limit
  78. GRB241120A: OHP/T193 optical observations
  79. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  80. GRB 241120A: Mondy and AbAO optical observations
  81. EP241119a: Optical upper limits with Kinder observations
  82. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  83. EP241119a: GIT optical upper limits
  84. EP241119a : J-band observations with WINTER
  85. GRB 241120A: Fermi GBM Observation
  86. EP241119a: EP detection of a fast X-ray transient
  87. GRB241120A: a long GRB detected by INTEGRAL
  88. GRB 241112B: Mephisto further optical observations
  89. GRB 241030A: J-band observations
  90. GRB 241115a: PRIME near-infrared upper limits
  91. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  92. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  93. GRB 241115B: Fermi GBM Observation
  94. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  95. Updates to IceCube realtime alert system for muon tracks
  96. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  97. GRB 241117A: Fermi GBM Detection
  98. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  99. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  100. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst

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