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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"

45452 results found.

  1. GRB 260520A: Fermi GBM Final Localization
  2. GRB 260519D: Fermi GBM Final Localization Correction
  3. GRB 260519C: NuSTAR detection of prompt emission
  4. Konus-Wind detection of GRB 260518A
  5. GRB 260519B: Fermi GBM Final Localization
  6. GRB 260519A: Fermi GBM Final Localization
  7. GRB 260518A: AstroSat CZTI detection of a long burst
  8. GRB 260516D: SVOM/ECLAIRs refined analysis
  9. GRB 260515A: SVOM/ECLAIRs refined analysis
  10. GRB 260421B: radio detection with the VLA
  11. GRID detection of GRB 260511A
  12. GRB 260509A: CrAO ZTSh optical upper limit (Duplicate Submission)
  13. GRB 260509A: CrAO ZTSh optical upper limit
  14. GRB 260516D: EP-FXT follow-up observation
  15. GRB 260516D: GOTO optical counterpart detection
  16. GRB 260516D: LCO optical observations
  17. GRB 260515A: further Liverpool Telescope observations
  18. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  19. GRB 260516D: GTC/OSIRIS+ spectroscopic redshift z = 1.801
  20. GRB 260516D: GROWTH-India Telescope optical detection
  21. GRB 260516D: SVOM/VT optical bright candidate
  22. GRB 260516D: FRAM-ORM optical limit
  23. GRB 260515A: CrAO ZTSh BVRI optical observations
  24. Fermi GRB 260516C: Global MASTER-Net observations report
  25. SVOM GRB260516D: Global MASTER-Net observations report
  26. GRB 260516D: SVOM possible detection of a burst
  27. GRB 260516C: Fermi GBM Final Real-time Localization
  28. Konus-Wind detection of GRB 260515A
  29. GRB 260515A: Liverpool Telescope optical detection
  30. GRB 260515A: LCO optical counterpart detection
  31. Fermi Gamma-ray Burst Monitor trigger 800627191/260516518 is not a GRB
  32. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  33. GRB 260515A: EP-FXT follow-up observation
  34. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  35. EP260514a: NOT optical counterpart confirmation
  36. EP260514a: TRT optical counterpart candidate
  37. EP260514a: SVOM/VT optical candidate
  38. Fermi GRB 260516B: Global MASTER-Net observations report
  39. GRB 260516B: Fermi GBM Final Real-time Localization
  40. Fermi Gamma-ray Burst Monitor trigger 800592653/260516119 is not a GRB
  41. GRB 260515A: SVOM/VT optical observations
  42. GRB 260515A: OHP/T193 optical observations
  43. EP260514a: COLIBRÍ optical upper limits
  44. GRB 260516A: Fermi GBM Final Real-time Localization
  45. GRID detection of GRB 260507A
  46. GRB 260515A: GTC/OSIRIS+ spectroscopic redshift z = 0.764
  47. GRB 260515A: LCO optical observations
  48. SVOM GRB 260515A: Global MASTER-Net observations report
  49. GRB 260515A: NOT optical observations.
  50. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  51. GRB 260515A: SVOM/VT optical candidate from VHF data
  52. GRB 260515A: JinShan optical counterpart candidate
  53. GRB 260515A: SVOM detection of a burst
  54. GRB 260510C: Glowbug gamma-ray detection
  55. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  56. EP260514a: GROWTH-India Telescope optical upper limit
  57. GRB 260511B: NOT optical observations
  58. Konus-Wind detection of GRB 260512A
  59. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  60. GRB 260511B: GMG Optical Upper Limit
  61. EP260514a: Global MASTER-Net observations report
  62. EP260514a: Einstein Probe detection of a fast X-ray transient
  63. EP260512a: LCO optical upper limits
  64. IPN triangulation of GRB 260512A
  65. GRB 260511B: Mephisto multi-band optical followup
  66. Fermi GRB 260514A: Global MASTER-Net observations report
  67. GRB 260512A: AstroSat CZTI detection
  68. The EP-WXT trigger 01709262077 is likely a flaring star
  69. EP260512a: EP-FXT follow-up observation
  70. EP260507a: Xinglong Schmidt optical counterpart detection
  71. GRB 260514A: Fermi GBM Final Real-time Localization
  72. EP260512a: Global MASTER-Net observations report
  73. Fermi GRB 260513A: Global MASTER-Net observations report
  74. Fermi GRB 260512A: Global MASTER-Net observations report
  75. GRB 260511B: further SAO RAS optical observations
  76. GRB 260513A: Fermi GBM Final Real-time Localization
  77. GRB 260509A: SVOM/VT optical observations
  78. Konus-Wind detection of GRB 260511B
  79. The EP-WXT trigger 01709262036 is likely a flaring star
  80. EP260512a: COLIBRÍ optical upper limits
  81. EP260512a: Einstein Probe detection of an X-ray transient
  82. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  83. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  84. GRB 260512A: NuSTAR detection of prompt emission
  85. GRB 260509A: Infrared J and Hs observations with MDM/MIRAGE
  86. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  87. EP260507a: Infrared J and Hs upper limits with MDM/MIRAGE
  88. GRB 260512A: Fermi GBM Final Real-time Localization
  89. GRB 260511A: Glowbug gamma-ray detection
  90. Konus-Wind detection of GRB 260511A
  91. MASS-Cube (GRID 2.0) detection of GRB 260511A
  92. MASS-Cube (GRID 2.0) detection of GRB 260507A
  93. GRB 260511B: SAO RAS optical observations
  94. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  95. GRB 260511B: FRAM-ORM optical detection
  96. GRB 260511A: EP-FXT follow-up observation
  97. GRB 260511B: EP-FXT follow-up observation
  98. GRB 260511B: LCO optical counterpart detection
  99. GRB260511B: MAO/AZT-22 optical observations
  100. GRB 260511A: SVOM/VT optical observations

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