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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"
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submitter:"Judith Racusin"

28271 results found.

  1. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  2. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  3. GRB 241128A: AbAO optical upper limit
  4. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  5. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  7. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  8. GRB 241128A: Swift-BAT refined analysis
  9. GRB 241127A: Swift-BAT refined analysis
  10. GRB 241127A: PRIME near-infrared detection
  11. GRB 241128A: Mondy optical observations
  12. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  13. Swift-XRT observations of IceCube -241127A
  14. Fermi-LAT gamma-ray observations of IceCube-241127A
  15. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  16. GRB 241128A: Swift-XRT refined Analysis
  17. GRB 241128A: Enhanced Swift-XRT position
  18. GRB 241128A: NOT optical observations
  19. GRB 241128A: LCO optical detection
  20. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  21. GRB 241128A: Swift-XRT afterglow detection
  22. GRB 241128A: Swift detection of a burst
  23. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  24. GRB 241127A: Swift/UVOT Detection
  25. GRB 241127A: Swift-XRT refined Analysis
  26. GRB 241127A: Enhanced Swift-XRT position
  27. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  28. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  29. Swift GRB241127.91: Global MASTER-Net OT detection
  30. EP241126a: WFST Observations
  31. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  32. GRB 241127A: Swift detection of a burst with an optical counterpart
  33. Swift GRB241127.91: Global MASTER-Net OT detection
  34. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  35. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  36. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  37. EP241126a: Optical Upper limits with Kinder observations
  38. IPN triangulation of GRB 241114B
  39. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  40. EP241126a: GSP detects optical counterpart
  41. EP241126a: TRT optical counterpart detection
  42. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  43. EP241126a: EP detection of a fast X-ray transient
  44. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  45. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  46. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  47. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  48. GECAM detection of a short burst from SGR 1830
  49. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  50. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  51. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  52. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  53. GRB 241026A: radio detection with the VLA
  54. EP241125a: Optical upper limit with Kinder observations
  55. EP241125a: EP detection of an X-ray transient
  56. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  57. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  58. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  59. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  60. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  61. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  62. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  63. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  64. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  65. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  66. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  67. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  68. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  69. IPN triangulation of GRB 241117A
  70. GRB 241026A: VIRT Optical Upper Limit
  71. GRB 241025A: VIRT Optical Upper Limit
  72. GRB241120A: OHP/T193 optical observations
  73. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  74. GRB 241120A: Mondy and AbAO optical observations
  75. EP241119a: Optical upper limits with Kinder observations
  76. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  77. EP241119a: GIT optical upper limits
  78. EP241119a : J-band observations with WINTER
  79. GRB 241120A: Fermi GBM Observation
  80. EP241119a: EP detection of a fast X-ray transient
  81. GRB241120A: a long GRB detected by INTEGRAL
  82. GRB 241112B: Mephisto further optical observations
  83. GRB 241030A: J-band observations
  84. GRB 241115a: PRIME near-infrared upper limits
  85. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  86. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  87. GRB 241115B: Fermi GBM Observation
  88. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  89. Updates to IceCube realtime alert system for muon tracks
  90. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  91. GRB 241117A: Fermi GBM Detection
  92. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  93. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  94. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  95. GRB 241115C: Fermi GBM Observation
  96. GRB 241115A: Swift-XRT afterglow detection
  97. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  98. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  99. GRB 241115A: Mephisto upper limits
  100. GRB 241113B: Mephisto upper limits

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