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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"

3115 results found.

  1. Konus-Wind detection of GRB 231215A
  2. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  3. GRB 231215A: Fermi GBM observation
  4. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  5. GRB 231215A: AGILE detection
  6. GRB 231215A: AstroSat CZTI detection
  7. GRB 231215B: Fermi GBM Final Real-time Localization
  8. GRB 231215A: Swift detection of a burst
  9. Fermi trigger No 724278269: Global MASTER-Net observations report
  10. IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
  11. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 2047+098, located inside the IceCube-231211A error region
  12. IceCube-231211A - IceCube observation of a high-energy neutrino candidate track-like event
  13. IceCube-231202A: No candidates from the Zwicky Transient Facility
  14. IPN triangulation of GRB 231129C
  15. GRB 231208A: AstroSat CZTI detection of a faint burst
  16. GRB 231205B: Swift detection of a burst
  17. Fermi trigger No 723435916: Global MASTER-Net observations report
  18. Fermi trigger No 723326169: Global MASTER-Net observations report
  19. Fermi trigger No 723412808: Global MASTER-Net observations report
  20. GRB 231203A: Fermi GBM Final Real-time Localization
  21. GRB 231129A : MITSuME Akeno optical upper limits
  22. GRB 231129C: MAXI/GSC detection
  23. GRB 231117A: MeerKAT 1.3GHz detection
  24. GRB 231125A: GRBAlpha detection
  25. GRB 231125A: CALET Gamma-Ray Burst Monitor detection
  26. GRB 231125A (short): Glowbug gamma-ray detection
  27. GRB 231125A: AstroSat CZTI detection of a short burst
  28. GRB 231111A: Optical follow-up observations at Terskol, AbAO, Maidanak, Mondy, Assy
  29. Fermi trigger No 722462310: Global MASTER-Net observations report
  30. GRB 231115A: JinShan optical upper limits
  31. GRB 231116A: Fermi GBM Final Real-time Localization
  32. GRB 231115A: MASTER optical observations
  33. Integral GRB231115.65: Global MASTER-Net observations report
  34. GRB 231115A: GROWTH-India discovery of a potential optical counterpart
  35. Fermi GRB 231115A: Global MASTER-Net observations report
  36. GRB 231104A: VZLUSAT-2 detection
  37. GRB231111A: YAHPT Observations
  38. Swift GRB231110.89: Global MASTER-Net observations report
  39. IceCube-231103A: No candidates from the Zwicky Transient Facility
  40. Fermi GRB 231108A: Global MASTER-Net observations report
  41. GRB 231104A: Swift-BAT refined analysis
  42. Fermi trigger No 721006392: Global MASTER-Net observations report
  43. Fermi GRB 231106A: Global MASTER-Net observations report
  44. GRB 231104A: NuSTAR Observation of the prompt emission
  45. GRB 231104A: Fermi GBM Observation
  46. GRB 231104B: Fermi GBM Final Real-time Localization
  47. Fermi GRB 231103A: Global MASTER-Net observations report
  48. GRB 231104A: AstroSat CZTI detection
  49. GRB 231104A: Fermi-LAT detection
  50. GRB 231104A: Enhanced Swift-XRT position
  51. GRB 231104A: Swift detection of a bright burst
  52. GRB 231104A: Fermi GBM Final Real-time Localization
  53. LIGO/Virgo/KAGRA S231102i: Global MASTER-Net observations report
  54. Fermi GRB 231030B: Global MASTER-Net observations report
  55. IceCube Alert 231027.18: Global MASTER-Net observations report
  56. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  57. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  58. Fermi trigger No 719846439: Global MASTER-Net observations report
  59. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  60. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  61. Fermi GRB 231019A: Global MASTER-Net observations report
  62. GRB 231017A: JinShan optical upper limit
  63. GRB 231015A: Glowbug gamma-ray detection
  64. IceCube-231004A: One Candidate Counterpart from the Zwicky Transient Facility
  65. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  66. GRB 230906A: optical counterpart
  67. Fermi trigger No 716449174: Global MASTER-Net observations report
  68. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  69. GRB 230911A: GOTO optical counterpart candidate
  70. GRB 230906A: Chandra detection of the X-ray afterglow
  71. GRB 230911C: Swift detection of a burst
  72. GRB 230906A: Swift-XRT observations
  73. IPN triangulation of GRB 230906A (short)
  74. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  75. Fermi trigger No 715429986: Global MASTER-Net observations report
  76. Fermi GRB 230904A: Global MASTER-Net observations report
  77. GRB 230828A: AstroSat CZTI detection
  78. Fermi GRB 230827A: Global MASTER-Net observations report
  79. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  80. GRB 230826A: Swift detection of a burst
  81. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  82. Swift GRB230825.75: Global MASTER-Net observations report
  83. GRB 230812B: radio detection with the VLA
  84. Fermi trigger No 714618399: Global MASTER-Net observations report
  85. GRB 230812B: Assy optical observations, possible SN rise
  86. Swift GRB230820.81: Global MASTER-Net observations report
  87. Fermi GRB 230818A: Global MASTER-Net observations report
  88. Swift GRB230818.98: Global MASTER-Net observations report
  89. IPN triangulation of GRB 230815B
  90. Fermi GRB 230814A: Global MASTER-Net observations report
  91. GRB 230812B: continued AbAO optical afterglow observations
  92. GRB 230812B: Optical observaions from Rozhen Observatory
  93. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  94. GRB 230812B: CrAO ZTSh optical observations
  95. GRB 230812B: Koshka Zeiss-1000 optical observations
  96. GRB 230812B: Leavitt Observatory optical observations
  97. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  98. GRB 230812B: AbAO optical observations
  99. GRB 230812B: Montarrenti Observatory optical observations
  100. GRB 230812B: Detected Optical Afterglow Candidate

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