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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"

28301 results found.

  1. GRB 240527B: BALROG localization (Fermi Trigger 738511436 / GRB 240527586)
  2. GRB 240523A: Swift-BAT refined analysis
  3. LIGO/Virgo/KAGRA S240525p: Updated Sky localization
  4. LIGO/Virgo/KAGRA S240525p: Identification of a GW compact binary merger candidate
  5. GRB 240523A: Swift-XRT refined Analysis
  6. GRB 240523A: Enhanced Swift-XRT position
  7. GRB 240523A: Swift detection of a burst
  8. GRB 240521B: Fermi GBM Observation
  9. Fermi GBM Sub-Threshold Detection of GRB 240516B
  10. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  11. LIGO/Virgo/KAGRA S240520cv: Updated Sky localization and EM Bright Classification
  12. EP240518a: GSP optical upper limit
  13. GRB 240521A: GECAM-B detection of a long burst
  14. GRB 240516B: AstroSat CZTI detection
  15. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  16. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  18. LIGO/Virgo/KAGRA S240520cv: Identification of a GW compact binary merger candidate
  19. IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
  20. GRB 240514B: VZLUSAT-2 detection
  21. GRB 240504A: VZLUSAT-2 detection
  22. GRB 240502A: VZLUSAT-2 detection
  23. GRB 240516A: Swift/UVOT Upper Limits
  24. EP240518a: possibly identified with a flare star by EP-FXT
  25. GRB 240519A: BALROG localization (Fermi Trigger 737788024 / GRB 240519213)
  26. EP240518a: EP-WXT detection of a new X-ray transient
  27. LIGO/Virgo/KAGRA S240514c: Updated Sky localization
  28. GRB 240516A: Swift-BAT refined analysis
  29. IPN triangulation of GRB 240514B (short)
  30. GRB 240516A: Swift-XRT refined Analysis
  31. GRB 240516A: Fermi GBM Observation
  32. GRB 240511A: Observations from GTC/OSIRIS+
  33. GRB 240516A: Swift detection of a burst
  34. GRB 240511A: radio detection of afterglow candidate
  35. MAXI GRB240514.78: Global MASTER-Net observations report
  36. GRB 240514E: MAXI/GSC detection of a probable afterglow
  37. LIGO/Virgo/KAGRA S240514x: Updated Sky localization
  38. LIGO/Virgo/KAGRA S240515m: Identification of a GW compact binary merger candidate
  39. GRB 240513A: Fermi GBM observation
  40. GRB 240513A: Swift-XRT observations
  41. LIGO/Virgo/KAGRA S240513ei: Updated Sky localization
  42. LIGO/Virgo/KAGRA S240514x: Identification of a GW compact binary merger candidate
  43. LIGO/Virgo/KAGRA S240514c: Identification of a GW compact binary merger candidate
  44. transient: Xinglong Nearby Galaxy Supernova Survey detection of AT2024iss
  45. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  47. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  48. LIGO/Virgo/KAGRA S240513ei: Identification of a GW compact binary merger candidate
  49. GRB 240511A: Fermi GBM Observation
  50. GRB 240511A: Swift-BAT refined analysis
  51. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  52. GRB 240511A: J-band observations with WINTER
  53. Fermi trigger No 737247400: Global MASTER-Net observations report
  54. Fermi trigger No 737168073: Global MASTER-Net observations report
  55. GRB 240511A: Enhanced Swift-XRT position
  56. GRB 240511A : MITSuME Akeno optical upper limits
  57. LIGO/Virgo/KAGRA S240512r: Updated Sky localization and EM Bright Classification
  58. GRB 240511A: Swift-XRT refined Analysis
  59. LIGO/Virgo/KAGRA S240512r: Identification of a GW compact binary merger candidate
  60. GRB 240511A: Swift detection of a burst
  61. LIGO/Virgo/KAGRA S240511i: Updated Sky localization
  62. Fermi trigger No 737111207: Global MASTER-Net observations report
  63. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  65. LIGO/Virgo/KAGRA S240422ed: P200 observations of AT2024hit
  66. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  67. EP240506a: Xinglong optical upper limit
  68. GRB 240504A: Fermi GBM Observation
  69. EP240506a: Archival radio searching
  70. EP240506a: TRT optical upper limit
  71. LIGO/Virgo/KAGRA S240507p: Updated Sky localization and EM Bright Classification
  72. LIGO/Virgo/KAGRA S240422ed: Upper limits from a two-week IceCube neutrino search
  73. EP240506a: Optical upper limit with Kinder observations
  74. IPN triangulation of GRB 240504A
  75. GRB 240502A: 1.3m DFOT Optical upper limit
  76. EP240506a: EP-WXT detection of a new fast X-ray transient
  77. LIGO/Virgo/KAGRA S240507p: Identification of a GW compact binary merger candidate
  78. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  79. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  80. LIGO/Virgo/KAGRA S240505av: Updated Sky localization and EM Bright Classification
  81. LIGO/Virgo/KAGRA S240505av: Identification of a GW compact binary merger candidate
  82. Fermi trigger No 736461232: Global MASTER-Net observations report
  83. GW170817: VLA observations at ~5.5 yrs since merger
  84. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  85. GRB 240502A: Fermi GBM Observation
  86. GRB 240415A 1.3m DFOT Optical upper limit
  87. LIGO/Virgo/KAGRA S240501an: Updated Sky localization and EM Bright Classification
  88. LIGO/Virgo/KAGRA S240430ca: Updated Sky localization and EM Bright Classification
  89. GRB 240426A: VZLUSAT-2 detection
  90. GRB 240425A: VZLUSAT-2 detection
  91. MeerKAT Discovery of a Probable Radio Counterpart to EP240414a
  92. GRB 240501B: AstroSat CZTI detection
  93. GRB 240501A: Fermi GBM Final Real-time Localization
  94. GRB 240408B: VZLUSAT-2 detection
  95. GRB 240407A: VZLUSAT-2 detection
  96. LIGO/Virgo/KAGRA S240501an: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S240430ca: Updated Sky localization and EM Bright Classification
  98. LIGO/Virgo/KAGRA S240430ca: Identification of a GW compact binary merger candidate
  99. LIGO/Virgo/KAGRA S240422ed: GECKO/7DT ToO observations
  100. Additional DECam GW-MMADS Candidates from three nights of observations

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