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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"

28262 results found.

  1. GRB 241127A: PRIME near-infrared detection
  2. GRB 241128A: Mondy optical observations
  3. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  4. Swift-XRT observations of IceCube -241127A
  5. Fermi-LAT gamma-ray observations of IceCube-241127A
  6. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  7. GRB 241128A: Swift-XRT refined Analysis
  8. GRB 241128A: Enhanced Swift-XRT position
  9. GRB 241128A: NOT optical observations
  10. GRB 241128A: LCO optical detection
  11. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  12. GRB 241128A: Swift-XRT afterglow detection
  13. GRB 241128A: Swift detection of a burst
  14. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  15. GRB 241127A: Swift/UVOT Detection
  16. GRB 241127A: Swift-XRT refined Analysis
  17. GRB 241127A: Enhanced Swift-XRT position
  18. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  19. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  20. Swift GRB241127.91: Global MASTER-Net OT detection
  21. EP241126a: WFST Observations
  22. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  23. GRB 241127A: Swift detection of a burst with an optical counterpart
  24. Swift GRB241127.91: Global MASTER-Net OT detection
  25. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  26. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  27. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  28. EP241126a: Optical Upper limits with Kinder observations
  29. IPN triangulation of GRB 241114B
  30. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  31. EP241126a: GSP detects optical counterpart
  32. EP241126a: TRT optical counterpart detection
  33. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  34. EP241126a: EP detection of a fast X-ray transient
  35. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  36. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  37. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  38. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  39. GECAM detection of a short burst from SGR 1830
  40. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  41. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  42. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  43. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  44. GRB 241026A: radio detection with the VLA
  45. EP241125a: Optical upper limit with Kinder observations
  46. EP241125a: EP detection of an X-ray transient
  47. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  48. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  49. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  50. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  51. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  52. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  53. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  54. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  55. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  56. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  57. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  59. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  60. IPN triangulation of GRB 241117A
  61. GRB 241026A: VIRT Optical Upper Limit
  62. GRB 241025A: VIRT Optical Upper Limit
  63. GRB241120A: OHP/T193 optical observations
  64. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  65. GRB 241120A: Mondy and AbAO optical observations
  66. EP241119a: Optical upper limits with Kinder observations
  67. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  68. EP241119a: GIT optical upper limits
  69. EP241119a : J-band observations with WINTER
  70. GRB 241120A: Fermi GBM Observation
  71. EP241119a: EP detection of a fast X-ray transient
  72. GRB241120A: a long GRB detected by INTEGRAL
  73. GRB 241112B: Mephisto further optical observations
  74. GRB 241030A: J-band observations
  75. GRB 241115a: PRIME near-infrared upper limits
  76. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  77. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  78. GRB 241115B: Fermi GBM Observation
  79. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  80. Updates to IceCube realtime alert system for muon tracks
  81. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  82. GRB 241117A: Fermi GBM Detection
  83. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  84. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  85. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  86. GRB 241115C: Fermi GBM Observation
  87. GRB 241115A: Swift-XRT afterglow detection
  88. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  89. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  90. GRB 241115A: Mephisto upper limits
  91. GRB 241113B: Mephisto upper limits
  92. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  93. GRB 241115D / EP 241115a: SVOM/GRM observation
  94. EP241113a: Swift XRT weak detection
  95. GRB 241115A: Fermi GBM Observation
  96. GRB 241115A: LCOGT Optical Upper Limits
  97. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  98. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  99. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  100. EP241115a: EP detection of a fast X-ray transient

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