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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').
Advanced Search

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"

18517 results found.

  1. GRB 241114B: cubesat Avion detection
  2. GRB 241209A: VLT optical observations
  3. GRB 241209C: Fermi GBM Final Real-time Localization
  4. GRB 241209A: GOTO optical upper limits
  5. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  6. EP241208a: EP detection of a fast X-ray transient
  7. GRB 241209A: Swift detection of a short burst
  8. GRB 241209A: Fermi GBM Final Real-time Localization
  9. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  10. GRB 241206A: DDOTI Upper Limit on the Afterglow
  11. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  12. EP241206a: EP detection of a fast X-ray transient
  13. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  14. EP241201a: 1.6m Mephisto Optical Upper Limits
  15. GRB 241204A: COLIBRÍ Optical Upper Limit
  16. EP241202b: KAIT optical upper limit
  17. GRB 241204A: DDOTI Upper Limits on the Afterglow
  18. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  19. EP241202b: Kinder optical counterpart candidate
  20. EP241201a: EP-FXT follow-up observations
  21. EP241202b: EP detection of a fast X-ray transient
  22. EP241201a: NOT optical observations
  23. GRB 241128A: Swift/UVOT Upper Limits
  24. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  25. EP241201a: Kinder optical counterpart candidate
  26. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  27. EP241201a: EP detection of a fast X-ray transient
  28. EP241126a: 1.6m Mephisto Optical Upper Limits
  29. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  30. GRB 241128A: AbAO optical upper limit
  31. GRB 241127A: Swift-BAT refined analysis
  32. GRB 241127A: PRIME near-infrared detection
  33. GRB 241128A: Mondy optical observations
  34. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  35. Swift-XRT observations of IceCube -241127A
  36. GRB 241128A: Enhanced Swift-XRT position
  37. GRB 241128A: NOT optical observations
  38. GRB 241128A: LCO optical detection
  39. GRB 241128A: Swift-XRT afterglow detection
  40. GRB 241128A: Swift detection of a burst
  41. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  42. GRB 241127A: Swift/UVOT Detection
  43. GRB 241127A: Enhanced Swift-XRT position
  44. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  45. Swift GRB241127.91: Global MASTER-Net OT detection
  46. EP241126a: WFST Observations
  47. GRB 241127A: Swift detection of a burst with an optical counterpart
  48. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  49. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  50. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  51. EP241126a: Optical Upper limits with Kinder observations
  52. IPN triangulation of GRB 241114B
  53. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  54. EP241126a: EP-FXT follow-up observation update
  55. EP241126a: TRT optical counterpart detection
  56. EP241126a: EP detection of a fast X-ray transient
  57. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  58. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  59. GRB 241113B: EP-FXT afterglow detection
  60. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  61. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  62. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  63. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  64. GRB 241026A: radio detection with the VLA
  65. EP241125a: Optical upper limit with Kinder observations
  66. EP241125a: EP detection of an X-ray transient
  67. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  68. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  69. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  70. GRB 241105A: ATCA radio detection
  71. IPN triangulation of GRB 241117A
  72. GRB 241026A: VIRT Optical Upper Limit
  73. GRB 241025A: VIRT Optical Upper Limit
  74. GRB241120A: OHP/T193 optical observations
  75. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  76. GRB 241120A: Mondy and AbAO optical observations
  77. EP241119a: Optical upper limits with Kinder observations
  78. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  79. EP241119a: GIT optical upper limits
  80. GRB 241113A: Possible ATCA Radio detection
  81. EP241119a : J-band observations with WINTER
  82. EP241119a: EP detection of a fast X-ray transient
  83. GRB 241112B: Mephisto further optical observations
  84. GRB 241030A: J-band observations
  85. GRB 241115a: PRIME near-infrared upper limits
  86. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  87. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  88. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  89. GRB 241115A: Swift-XRT afterglow detection
  90. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  91. GRB 241115A: Mephisto upper limits
  92. GRB 241113B: Mephisto upper limits
  93. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  94. GRB 241115D / EP 241115a: SVOM/GRM observation
  95. The EP-WXT trigger 01709120856 is likely a flaring star
  96. EP241113a: Swift XRT weak detection
  97. GRB 241115A: Fermi GBM Observation
  98. GRB 241115A: LCOGT Optical Upper Limits
  99. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  100. EP241115a: EP detection of a fast X-ray transient

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