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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"

4572 results found.

  1. GRB 241214A: GRBAlpha detection
  2. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  3. Konus-Wind detection of GRB 241213A (EP 241213a)
  4. GRB 241214A: SVOM/GRM observation
  5. GRB 241213A: Swift-XRT refined Analysis
  6. GRB 241212A: SVOM detection of a bright long burst
  7. GRB 241207A: EIRSAT-1 GMOD Detection
  8. GRB 241209A: Swift-XRT refined Analysis
  9. EP241208a: Optical upper limit with Kinder observations
  10. Fermi trigger No 755485387: Global MASTER-Net observations report
  11. GRB 241209D: Swift-XRT refined Analysis
  12. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  13. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  14. Fermi GRB 241209A: Global MASTER-Net observations report
  15. Fermi trigger No 755277791: Global MASTER-Net observations report
  16. Fermi GRB 241207A: Global MASTER-Net observations report
  17. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  18. GRB 241130A: EIRSAT-1 GMOD Detection
  19. The EP-WXT trigger 01709126243 is not a real source
  20. Fermi trigger No 754701230: Global MASTER-Net observations report
  21. GRB 241128A: Swift-XRT refined Analysis
  22. Swift GRB241127.91: Global MASTER-Net OT detection
  23. Konus-Wind detection of GRB 241115D / EP 241115a
  24. GRB 241026A: radio detection with the VLA
  25. EP241125a: EP detection of an X-ray transient
  26. GRB 241113B: SVOM/VT optical afterglow observations
  27. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  28. GRB 241026A: VIRT Optical Upper Limit
  29. EP241119a: Global MASTER-Net observations report
  30. Fermi GRB 241118A: Global MASTER-Net observations report
  31. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  32. GRB 241115A: LCOGT Optical Upper Limits
  33. GRB 241115A: Fermi GBM Final Real-time Localization
  34. GRB 241113B: KAIT Optical Afterglow Candidate
  35. EP241113a: Global MASTER-Net observations report
  36. EP241113b: Global MASTER-Net observations report
  37. GRB 241113A: Swift-XRT refined Analysis
  38. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  39. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  40. Fermi trigger No 752990530: Global MASTER-Net observations report
  41. Fermi trigger No 752878030: Global MASTER-Net observations report
  42. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  43. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  44. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  45. EP241107A: MASTER optical observations of xray transient
  46. GRB 241105A: Swift/UVOT Detection
  47. GRB 241105A: Swift-XRT afterglow detection
  48. GRB 241105A: GOTO tentative optical counterpart candidate
  49. Fermi GRB 241105A: Global MASTER-Net observations report
  50. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  51. GRB 240821A: further radio observations with the VLA
  52. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  53. EP241103a: an X-ray transient detected by Einstein Probe
  54. Fermi trigger No 752083996: Global MASTER-Net observations report
  55. EP EP241030a: Global MASTER-Net observations report
  56. Fermi trigger No 752006065: Global MASTER-Net observations report
  57. GRB 241030A: Swift-XRT refined Analysis
  58. GRB 241030B: AKO Optical Afterglow Detection
  59. Fermi trigger No 751861204: Global MASTER-Net observations report
  60. Konus-Wind detection of GRB 241025A
  61. GRB 241026A: BTA and Zeiss-1000 optical observations
  62. GRB 241026A: Swift-XRT refined Analysis
  63. EP241021a: e-MERLIN radio observation
  64. Fermi trigger No 751616906: Global MASTER-Net observations report
  65. EP241021a: optical follow-up observations with the Liverpool Telescope
  66. EP241021a: Liverpool Telescope optical follow-up observations
  67. GRB 241025A: TRT optical afterglow observation
  68. Fermi GRB 241024B: Global MASTER-Net observations report
  69. GRB 241024B: Fermi GBM Final Localization
  70. GRB 241024A: Fermi GBM Final Localisation
  71. Fermi trigger No 751449953: Global MASTER-Net observations report
  72. EP241021a: Optical upper limits with Kinder observations
  73. Fermi trigger No 750788395: Global MASTER-Net observations report
  74. GRB 241006A: Swift-XRT refined Analysis
  75. IceCube Alert 241006.94: Global MASTER-Net observations report
  76. GRB 241002A: Swift-XRT refined Analysis
  77. EP trigger ID 01709064214: GOTO confirms detection as a flare star
  78. Fermi GRB 241002B: Global MASTER-Net observations report
  79. EP EP240930a: Global MASTER-Net observations report
  80. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  81. Fermi GRB 240929A: Global MASTER-Net observations report
  82. IPN triangulation of GRB 240918B
  83. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  84. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  85. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  86. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  87. Fermi GRB 240918A: Global MASTER-Net observations report
  88. EP EP240918a: Global MASTER-Net observations report
  89. EP240918a: JinShan optical upper limits
  90. EP240918a: GMG Optical Upper Limit
  91. EP240918a: an X-ray transient detected by Einstein Probe
  92. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  93. GRB 240912A: Swift-XRT refined Analysis
  94. IPN triangulation of GRB 240905B (short)
  95. EP240908a: Mondy and AbAO follow-up observations
  96. EP240908a: Updates on the WXT detection result around the trigger time
  97. EP240908a: optical afterglow candidate
  98. GRB 240905E: Swift-XRT refined Analysis
  99. GRB 240828B: GRANDMA Optical Upper Limit
  100. GRB 240828A: Swift-XRT afterglow detection

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