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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"

28284 results found.

  1. GRB 241130A: Fermi GBM Detection
  2. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  3. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  4. EP241201a: Kinder optical counterpart candidate
  5. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  6. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  7. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  8. EP241126a: 1.6m Mephisto Optical Upper Limits
  9. GRB 241201A: Fermi GBM Final Real-time Localization
  10. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  11. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  12. Fermi trigger No 754701230: Global MASTER-Net observations report
  13. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  14. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  15. GRB 241128A: AbAO optical upper limit
  16. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  17. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  18. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  19. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  20. GRB 241128A: Swift-BAT refined analysis
  21. GRB 241127A: Swift-BAT refined analysis
  22. GRB 241127A: PRIME near-infrared detection
  23. GRB 241128A: Mondy optical observations
  24. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  25. Swift-XRT observations of IceCube -241127A
  26. Fermi-LAT gamma-ray observations of IceCube-241127A
  27. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  28. GRB 241128A: Swift-XRT refined Analysis
  29. GRB 241128A: Enhanced Swift-XRT position
  30. GRB 241128A: NOT optical observations
  31. GRB 241128A: LCO optical detection
  32. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  33. GRB 241128A: Swift-XRT afterglow detection
  34. GRB 241128A: Swift detection of a burst
  35. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  36. GRB 241127A: Swift/UVOT Detection
  37. GRB 241127A: Swift-XRT refined Analysis
  38. GRB 241127A: Enhanced Swift-XRT position
  39. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  40. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  41. Swift GRB241127.91: Global MASTER-Net OT detection
  42. EP241126a: WFST Observations
  43. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  44. GRB 241127A: Swift detection of a burst with an optical counterpart
  45. Swift GRB241127.91: Global MASTER-Net OT detection
  46. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  47. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  48. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  49. EP241126a: Optical Upper limits with Kinder observations
  50. IPN triangulation of GRB 241114B
  51. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  52. EP241126a: GSP detects optical counterpart
  53. EP241126a: TRT optical counterpart detection
  54. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  55. EP241126a: EP detection of a fast X-ray transient
  56. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  57. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  58. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  59. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  60. GECAM detection of a short burst from SGR 1830
  61. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  62. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  63. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  64. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  65. GRB 241026A: radio detection with the VLA
  66. EP241125a: Optical upper limit with Kinder observations
  67. EP241125a: EP detection of an X-ray transient
  68. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  69. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  70. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  71. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  72. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  73. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  74. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  75. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  76. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  77. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  78. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  80. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  81. IPN triangulation of GRB 241117A
  82. GRB 241026A: VIRT Optical Upper Limit
  83. GRB 241025A: VIRT Optical Upper Limit
  84. GRB241120A: OHP/T193 optical observations
  85. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  86. GRB 241120A: Mondy and AbAO optical observations
  87. EP241119a: Optical upper limits with Kinder observations
  88. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  89. EP241119a: GIT optical upper limits
  90. EP241119a : J-band observations with WINTER
  91. GRB 241120A: Fermi GBM Observation
  92. EP241119a: EP detection of a fast X-ray transient
  93. GRB241120A: a long GRB detected by INTEGRAL
  94. GRB 241112B: Mephisto further optical observations
  95. GRB 241030A: J-band observations
  96. GRB 241115a: PRIME near-infrared upper limits
  97. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  98. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  99. GRB 241115B: Fermi GBM Observation
  100. LIGO/Virgo/KAGRA S241114y: Updated Sky localization

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