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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"

2722 results found.

  1. Fermi trigger No 737168073: Global MASTER-Net observations report
  2. Fermi trigger No 737105243: Global MASTER-Net observations report
  3. GRB 240511A: Fermi GBM Final Real-time Localization
  4. Fermi trigger No 737111207: Global MASTER-Net observations report
  5. IPN triangulation of GRB 240504A
  6. Fermi trigger No 736564880: Global MASTER-Net observations report
  7. GRB 240503A: AstroSat CZTI detection
  8. Fermi trigger No 736387941: Global MASTER-Net observations report
  9. Fermi GRB 240501A: Global MASTER-Net observations report
  10. Fermi trigger No 736197684: Global MASTER-Net observations report
  11. GRB 240501B: AstroSat CZTI detection
  12. GRB 240426A: AstroSat CZTI detection
  13. EP240426a: YAHPT optical upper limit
  14. LIGO/Virgo/KAGRA S240422ed: Continued Magellan Observations
  15. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility contuinued observations of S240422ed and candidate analysis
  16. LIGO/Virgo/KAGRA S240422ed: Further near-infrared observations with Subaru/MOIRCS by J-GEM Collaboration
  17. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA and Kilonova-Catcher galaxy targeting observations
  18. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  19. LIGO/Virgo/KAGRA S240422ed: Subaru/MOIRCS near-infrared observations by J-GEM Collaboration
  20. LIGO/Virgo/KAGRA S240422ed: GOTO counterpart search
  21. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility observations and candidates
  22. LIGO/Virgo/KAGRA S240422ed: Magellan Observations
  23. Fermi GRB 240422A: Global MASTER-Net observations report
  24. Fermi GRB 240421B: Global MASTER-Net observations report
  25. Fermi trigger No 735280430: Global MASTER-Net observations report
  26. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  27. Fermi GRB 240417A: Global MASTER-Net observations report
  28. Improved IPN triangulation of GRB 240411A
  29. EP240416A: MASTER optical observations
  30. Fermi GRB 240415A: Global MASTER-Net observations report
  31. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  32. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  33. GRB 240411B: CrAO/ZTSh optical observations
  34. IceCube Alert 240412.23: Global MASTER-Net observations report
  35. Swift Trigger 1220736: detection of 4U 1543-62.
  36. Fermi GRB 240407A: Global MASTER-Net observations report
  37. GRB 240405B: Fermi GBM Final Real-time Localization
  38. GRB 240405A: Fermi GBM Final Real-time Localization
  39. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  40. Konus-Wind detection of LXT 240402A/GRB 240402B
  41. LXT 240402A: MASTER optical observations with AGN in error-box
  42. GRB 240402B: GECAM-C detection
  43. X-ray transient LXT 240402A: LEIA detection
  44. EP240331A: MASTER optical observations
  45. Fermi trigger No 733366352: Global MASTER-Net observations report
  46. Fermi GRB 240329A: Global MASTER-Net observations report
  47. GRB 240329A: Fermi GBM Final Real-time Localization
  48. Fermi GRB 240328B: Global MASTER-Net observations report
  49. Fermi GRB 240328A: Global MASTER-Net observations report
  50. IceCube-240327B: No candidates from the Zwicky Transient Facility
  51. GRB 240328A: Fermi GBM Final Real-time Localization
  52. IceCube Alert 240327.68: Global MASTER-Net observations report
  53. Fermi trigger No 733097506: Global MASTER-Net observations report
  54. Fermi trigger No 733092476: Global MASTER-Net observations report
  55. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  56. GRB 240320A: Fermi GBM Final Real-time Localization
  57. Fermi GRB 240318A: Global MASTER-Net observations report
  58. GRB 240317A: AstroSat CZTI detection
  59. Fermi GRB 240317B: Global MASTER-Net observations report
  60. Fermi trigger No 732299243: Global MASTER-Net observations report
  61. Fermi trigger No 731839490: Global MASTER-Net observations report
  62. Fermi GRB 240310A: Global MASTER-Net observations report
  63. Fermi GRB 240306A: Global MASTER-Net observations report
  64. Fermi GRB 240305A: Global MASTER-Net observations report
  65. GRB 240218A: ALMA detection
  66. IPN triangulation of GRB 240229A
  67. GRB240218A: ATCA observation of the radio counterpart
  68. Swift Trigger 1218645: Another detection of Swift J151857.0-572147
  69. Konus-Wind detection of GRB 240225B (long)
  70. Fermi GRB 240227A: Global MASTER-Net observations report
  71. GRB 240218A: CMO SAI NIR upper limit
  72. Fermi trigger No 730618809: Global MASTER-Net observations report
  73. GRB 240218A: VLA detection
  74. Transient EPW20240219aa: 7DT Optical Upper Limits
  75. GRB 240215B: GRBAlpha detection
  76. Fermi trigger No 729914426: Global MASTER-Net observations report
  77. GRB 240218A: REM detection of a NIR afterglow candidate
  78. Swift GRB240218.08: Global MASTER-Net observations report
  79. Fermi trigger No 729703985: Global MASTER-Net observations report
  80. GRB 240214A/1H 0451-560: MAXI/GSC detection
  81. Fermi GRB 240213A: Global MASTER-Net observations report
  82. GRB 240209A: GOTO optical counterpart candidate
  83. Fermi trigger No 729152364: Global MASTER-Net observations report
  84. Fermi trigger No 729012023: Global MASTER-Net observations report
  85. GRB 240205B: Fermi GBM Observation
  86. Fermi trigger No 728749569: Global MASTER-Net observations report
  87. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  88. Swift GRB240205.93: Global MASTER-Net observations report
  89. Fermi Gamma-ray Burst Monitor trigger 728740048/240204491 is not a GRB
  90. Fermi trigger No 728796365: Global MASTER-Net observations report
  91. IceCube Alert 240204.38: Global MASTER-Net observations report
  92. GRB 240127A: Fermi GBM Final Real-time Localization
  93. GRB 240123A: GRBAlpha detection
  94. GRB 240118A: Mondy optical observations
  95. GRB 240118A: Swift-XRT afterglow detection
  96. GRB 240118A: AbAO optical upper limit
  97. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240118A
  98. IPN triangulation of GRB 240112A (long)
  99. GRB 240115B: AstroSat CZTI detection
  100. GRB 240107A: VZLUSAT-2 detection

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