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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').
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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"

2722 results found.

  1. GRB 240115B: Fermi GBM Final Real-time Localization
  2. Fermi trigger No 726774492: Global MASTER-Net observations report
  3. Fermi GRB 240112B: Global MASTER-Net observations report
  4. IceCube-240105A: Three candidates from the Zwicky Transient Facility
  5. GRB 240107A: MAXI/GSC detection
  6. Fermi trigger No 726194053: Global MASTER-Net observations report
  7. GRB 231230A: GOTO optical upper limits
  8. Fermi trigger No 725592555: Global MASTER-Net observations report
  9. LAT GRB231222.31: Global MASTER-Net observations report
  10. GRID detection of GRB 231215A
  11. Fermi trigger No 724781422: Global MASTER-Net observations report
  12. GRB 231215A: GRBAlpha detection
  13. Swift GRB231216.77: Global MASTER-Net observations report
  14. Konus-Wind detection of GRB 231215A
  15. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  16. GRB 231215A: Fermi GBM observation
  17. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  18. GRB 231215A: AGILE detection
  19. GRB 231215A: AstroSat CZTI detection
  20. GRB 231215B: Fermi GBM Final Real-time Localization
  21. GRB 231215A: Swift detection of a burst
  22. Fermi trigger No 724278269: Global MASTER-Net observations report
  23. IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
  24. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 2047+098, located inside the IceCube-231211A error region
  25. IceCube-231211A - IceCube observation of a high-energy neutrino candidate track-like event
  26. IceCube-231202A: No candidates from the Zwicky Transient Facility
  27. IPN triangulation of GRB 231129C
  28. GRB 231208A: AstroSat CZTI detection of a faint burst
  29. GRB 231205B: Swift detection of a burst
  30. Fermi trigger No 723435916: Global MASTER-Net observations report
  31. Fermi trigger No 723326169: Global MASTER-Net observations report
  32. Fermi trigger No 723412808: Global MASTER-Net observations report
  33. GRB 231203A: Fermi GBM Final Real-time Localization
  34. GRB 231129A : MITSuME Akeno optical upper limits
  35. GRB 231129C: MAXI/GSC detection
  36. GRB 231117A: MeerKAT 1.3GHz detection
  37. GRB 231125A: GRBAlpha detection
  38. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  39. GRB 231125A (short): Glowbug gamma-ray detection
  40. GRB 231125A: AstroSat CZTI detection of a short burst
  41. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  42. Fermi trigger No 722462310: Global MASTER-Net observations report
  43. GRB 231115A: JinShan optical upper limits
  44. GRB 231116A: Fermi GBM Final Real-time Localization
  45. GRB 231115A: MASTER optical observations
  46. Integral GRB231115.65: Global MASTER-Net observations report
  47. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  48. Fermi GRB 231115A: Global MASTER-Net observations report
  49. GRB 231104A: VZLUSAT-2 detection
  50. GRB231111A: YAHPT Observations
  51. Swift GRB231110.89: Global MASTER-Net observations report
  52. IceCube-231103A: No candidates from the Zwicky Transient Facility
  53. Fermi GRB 231108A: Global MASTER-Net observations report
  54. GRB 231104A: Swift-BAT refined analysis
  55. Fermi trigger No 721006392: Global MASTER-Net observations report
  56. Fermi GRB 231106A: Global MASTER-Net observations report
  57. GRB 231104A: NuSTAR Observation of the prompt emission
  58. GRB 231104A: Fermi GBM Observation
  59. GRB 231104B: Fermi GBM Final Real-time Localization
  60. Fermi GRB 231103A: Global MASTER-Net observations report
  61. GRB 231104A: AstroSat CZTI detection
  62. GRB 231104A: Fermi-LAT detection
  63. GRB 231104A: Enhanced Swift-XRT position
  64. GRB 231104A: Swift detection of a bright burst
  65. GRB 231104A: Fermi GBM Final Real-time Localization
  66. LIGO/Virgo/KAGRA S231102i: Global MASTER-Net observations report
  67. Fermi GRB 231030B: Global MASTER-Net observations report
  68. IceCube Alert 231027.18: Global MASTER-Net observations report
  69. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  70. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  71. Fermi trigger No 719846439: Global MASTER-Net observations report
  72. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  73. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  74. Fermi GRB 231019A: Global MASTER-Net observations report
  75. GRB 231017A: JinShan optical upper limit
  76. GRB 231015A: Glowbug gamma-ray detection
  77. IceCube-231004A: One Candidate Counterpart from the Zwicky Transient Facility
  78. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  79. GRB 230906A: optical counterpart
  80. Fermi trigger No 716449174: Global MASTER-Net observations report
  81. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  82. GRB 230911A: GOTO optical counterpart candidate
  83. GRB 230906A: Chandra detection of the X-ray afterglow
  84. GRB 230911C: Swift detection of a burst
  85. GRB 230906A: Swift-XRT observations
  86. IPN triangulation of GRB 230906A (short)
  87. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  88. Fermi trigger No 715429986: Global MASTER-Net observations report
  89. Fermi GRB 230904A: Global MASTER-Net observations report
  90. GRB 230828A: AstroSat CZTI detection
  91. Fermi GRB 230827A: Global MASTER-Net observations report
  92. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  93. GRB 230826A: Swift detection of a burst
  94. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  95. Swift GRB230825.75: Global MASTER-Net observations report
  96. GRB 230812B: radio detection with the VLA
  97. Fermi trigger No 714618399: Global MASTER-Net observations report
  98. GRB 230812B: Assy optical observations, possible SN rise
  99. Swift GRB230820.81: Global MASTER-Net observations report
  100. Fermi GRB 230818A: Global MASTER-Net observations report

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