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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

19032 results found.

  1. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  2. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  3. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  4. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  5. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  6. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  7. Konus-Wind detection of GRB 241117A
  8. IPN triangulation of GRB 241117A
  9. GRB 241025A: VIRT Optical Upper Limit
  10. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  11. GRB 241115a: PRIME near-infrared upper limits
  12. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  13. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  14. GRB 241115B: Fermi GBM Observation
  15. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  16. GRB 241115C: Fermi GBM Observation
  17. GRB 241115A: Swift-XRT afterglow detection
  18. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  19. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  20. EP241113a: Swift XRT weak detection
  21. GRB 241115A: Fermi GBM Observation
  22. GRB 241115A: LCOGT Optical Upper Limits
  23. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  24. Swift GRB 241115A: Global MASTER-Net observations report
  25. GRB 241115A: Swift detection of a burst
  26. GRB 241113A: Swift-BAT refined analysis
  27. GRB 241113A: PRIME near-infrared upper limits
  28. GRB 241113A: J-band observations with WINTER
  29. GRB 241113B: Swift-XRT observations
  30. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  31. GRB 241113A: KAIT optical observations
  32. GRB 241113A: Swift-XRT refined Analysis
  33. GRB 241113A: Swift/UVOT Detection
  34. GRB 241113A: REM detection of the optical/NIR afterglow
  35. Konus-Wind detection of GRB 241107A (short/hard)
  36. GRB 241113B: Swift ToO observations
  37. GRB 241113A: LCO optical observations
  38. GRB 241113A: Enhanced Swift-XRT position
  39. GRB241113A: LCOGT (40-cm) optical counterpart detection
  40. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  41. GRB 241113A: Swift detection of a burst with an optical counterpart
  42. Swift GRB241113.33: Global MASTER-Net observations report
  43. SVOM/GRM detection of a short burst from SGR 1E1841-045
  44. GRB 241107A: GROWTH-India telescope optical upper limit
  45. GRB 241112B: Swift-XRT afterglow detection
  46. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  47. GRB 241112B: Swift ToO observations
  48. GRB 241107A: INTEGRAL IBIS localization
  49. IPN triangulation of GRB 241107A (short/hard)
  50. GRB 241025A: VZLUSAT-2 detection
  51. GRB 241108A: Swift-XRT observations
  52. GRB 241108A: Swift ToO observations
  53. GRB 241030A: TESS observations
  54. GRB 241105A: EP-FXT follow-up observations
  55. GRB 241105A: SVOM/GRM observation
  56. GRB 241105a: PRIME near-infrared upper limits
  57. GRB 241105A: Swift/UVOT Detection
  58. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  59. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  60. GRB 241105A: BOOTES-7 optical detection
  61. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  62. GRB 241105A: Swift-XRT afterglow detection
  63. GRB 241104A: Swift-XRT observations
  64. GRB 241105A: Swift ToO observations
  65. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  66. GRB 241104A: Swift ToO observations
  67. GRB 241030A: GRBAlpha detection
  68. EP241103a: GIT optical upper limit
  69. EP241103a: GOTO optical upper limit
  70. EP241103a: Swift XRT detection and improved X-ray position
  71. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  72. GRB 241030A: Rapid release of TESS data.
  73. Swift GRB 241101A: Global MASTER-Net observations report
  74. GRB 241101A: FRAM-ORM optical limit
  75. GRB 241101A: Swift-BAT refined analysis
  76. GRB 241030B: Swift-XRT refined Analysis
  77. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  78. GRB 241101A: Swift detection of a burst
  79. GRB 241030B: Montarrenti Observatory optical upper limit
  80. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  81. GRB 241030A: Fermi GBM Observation
  82. GRB 241030B: LCOGT Optical Upper Limits
  83. GRB 241030B: Swift-BAT refined analysis
  84. GRB 241030A: Swift-BAT refined analysis
  85. GRB 241030B: Swift/UVOT Detection
  86. GRB 241029A: LCO optical detection
  87. Swift GRB241030.77: Global MASTER-Net observations report
  88. GRB 241030B: SVOM/GRM observation
  89. GRB 241030B : MITSuME Akeno optical upper limits
  90. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  91. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  92. GRB241030B: Fermi GBM Observation
  93. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  94. GRB 241030B: Enhanced Swift-XRT position
  95. GRB 241030B: optical observations from the INAF Asiago Observatory
  96. EP241021a: Swift-UVOT detection
  97. GRB241030B: GRANDMA/TAROT Upper Limit
  98. GRB 241030A: Swift-XRT refined Analysis
  99. GRB 241030B: AKO Optical Afterglow Detection
  100. GRB 241030B: Nanshan/HMT optical afterglow detection

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