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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').
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"

15361 results found.

  1. GRB 260909A: SVOM/ECLAIRs refined analysis
  2. GRB 260910B: GOTO tentative optical counterpart candidates
  3. GRB 260909A: Swift ToO observations
  4. EP260806a: VLA+ALMA radio detections
  5. GRB 260909A: OHP/T193 z-band upper limit
  6. GRB 260909A: VLT optical and near-infrared upper limits
  7. GRB 260909A: SVOM/GRM observation
  8. GRB 260909A: SVOM detection of a burst
  9. GRB 260903A: Swift ToO observations
  10. GRB 260903A: SVOM/ECLAIRs refined analysis
  11. GRB260903A: Liverpool Telescope optical observations
  12. GRB 260830A: GECAM-B detection of a burst
  13. GRB 260830A: Insight-HXMT/HE detection
  14. GRB 260903A: OHP/T193 optical afterglow detection
  15. GRB 260903A: NOT optical observations and afterglow fading
  16. NuSTAR Transient 260828: SOAR Optical Upper Limits
  17. GRB 260903A: Retraction of optical counterpart of GCN 45501
  18. GRB 260831A: GECAM-B observation
  19. GRB 260827A: Insight-HXMT/HE detection
  20. GRB 260903A: SVOM detection of a soft faint burst
  21. Konus-Wind detection of GRB 260829A
  22. GRB 260829A: SVOM/GRM observation
  23. GRB 260818A: ATCA detection of a candidate radio counterpart
  24. IceCube-260827A: No transient candidates from the Zwicky Transient Facility
  25. GRB 260831B / sb26083106: SVOM/GWAC-F60A/B confirmation of optical variation of nova V* GK Per
  26. SVOM trigger sb26083106 is not a GRB
  27. GRB 260829A: AstroSat CZTI detection
  28. GRB 260827A: SVOM/GRM observation
  29. NuSTAR 260828: a 1100s hard X-ray transient
  30. GRB 260831B: SVOM detection of a possible burst
  31. Fermi-LAT Gamma-ray Observations of IceCube-260827A
  32. Fermi-LAT Gamma-ray Observations of IceCube-260825A
  33. GRB 260829A: GECAM-B observation of a long burst
  34. GRB 260825A: SVOM/GRM observation of a long burst
  35. GRB 260825A: GECAM-B observation
  36. GRB 260829A: Fermi GBM Detection
  37. GRB 260825A: AstroSat CZTI detection
  38. IceCube-260827A: Upper limits from a search for additional neutrino events in IceCube
  39. IceCube-260825A: Upper limits from a search for additional neutrino events in IceCube
  40. IceCube-260825A: Upper limits from a search for additional neutrino events in IceCube
  41. GRB 260818B: VLT optical and nIR observations
  42. IceCube-260827A - IceCube observation of a high-energy neutrino candidate track-like event
  43. GRB 260818B: 6 GHz VLA observations
  44. GRB 260818B: SVOM/VT optical upper limit and continuous observations
  45. GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  46. GRB 260808B: SAO RAS observations of the optical rebrightening
  47. IceCube-260825A: No transient candidates from the Zwicky Transient Facility
  48. GRB 260809A: SVOM/ECLAIRs refined analysis
  49. IceCube-Cascade 260824A: Upper limits from a search for additional neutrino events in IceCube
  50. IceCube-260825A - IceCube observation of a high-energy neutrino candidate track-like event
  51. GRB 260822A: PRIME near-infrared upper limits from multiple epochs
  52. GRB 260818A: further EP-FXT observations and X-ray afterglow confirmation
  53. GRB 260822A: Retraction of GOTO optical counterpart detection GCN 45431
  54. GRB 260822A: SVOM/VT optical detection of COLIBRÍ candidate
  55. GRB 260822A: GROWTH-India Telescope Upper Limits
  56. GRB 260822A: SVOM detection of a short burst
  57. Fermi-LAT Gamma-ray Observations of IceCube-260821A
  58. Fermi-LAT Gamma-ray Observations of IceCube-260807A
  59. IceCube-260821A: Upper limits from a search for additional neutrino events in IceCube
  60. GRB 260818B: SVOM/C-GFT optical upper limit
  61. EP260731a: SVOM/ECLAIRs detection through offline targeted search
  62. GRB 260820A: Insight-HXMT/HE detection
  63. IceCube-260821A - IceCube observation of a high-energy neutrino candidate track-like event
  64. GRB 260818B: SVOM/GRM observation
  65. GRB 260818B: Insight-HXMT detection
  66. GRB 260818A: J-band observations with WINTER
  67. GRB 260818B: SVOM/ECLAIRs refined analysis
  68. GRB 260818A: SVOM/ECLAIRs refined analysis
  69. GRB 260810A: SVOM/GRM observation
  70. GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  71. GRB 260818B: SVOM detection of a short burst
  72. GRB 260818A: LCO optical upper limits
  73. EP260812a: AbAO optical upper limit
  74. GRB 260810A: Insight-HXMT/HE detection
  75. GRB 260818A: SVOM possible detection of a long and faint GRB
  76. EP260806a: SVOM/ECLAIRs detection through targeted search
  77. EP260812b: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.034
  78. EP260806a: WFST optical observations
  79. EP260812b: Optical upper limit with Kinder
  80. GRB 260805D: SVOM/GRM detection of a possible magnetar burst
  81. GRB 260808B: Liverpool Telescope further optical observations
  82. GRB 260808B: GTC/OSIRIS+ spectroscopic redshift z = 1.295
  83. EP260812a: NOT and Liverpool Telescope upper limits:
  84. EP260812b: COLIBRÍ optical observations
  85. GRB 260808A: SVOM/GRM observation
  86. GRB 260808B: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical rebrightening
  87. GRB 260810A: AstroSat CZTI detection of a long burst
  88. GRB 260317A: SVOM/ECLAIRs detection through offline targeted search and its possible association to magnetar 1E 1841-04.5
  89. GRB 260806A: CALET Gamma-Ray Burst Monitor detection
  90. GRB 260808A: GECAM-B observation
  91. GRB 260807A: SVOM/ECLAIRs refined analysis
  92. IceCube-260807A: Upper limits from a search for additional neutrino events in IceCube
  93. GRB260808B: MAO/AZT-22 optical observations
  94. GRB 250607A: SVOM/ECLAIRs detection through offline targeted search
  95. GRB 260808A: CALET Gamma-Ray Burst Monitor detection
  96. GRB 260805C: CALET Gamma-Ray Burst Monitor detection
  97. GRB 260804A: CALET Gamma-Ray Burst Monitor detection
  98. GRB260809A/EPF_J234751.2+210212: EP-FXT follow-up observation
  99. GRB260809A: MAO/AZT-22 optical observations
  100. IceCube-260805A: Upper limits from a search for additional neutrino events in IceCube

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