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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"

32706 results found.

  1. EP260526a: LCO optical upper limits
  2. EP260526a: Einstein Probe detection of a fast X-ray transient
  3. GRB 260525A: AstroSat CZTI detection
  4. The EP-WXT trigger 01709266106 is not a real source
  5. Fermi GRB 260526A: Global MASTER-Net observations report
  6. Fermi GRB 260525A: Global MASTER-Net observations report
  7. GRB 260523B: AstroSat CZTI detection
  8. GRB 260523B: GECAM-B observation
  9. Fermi GRB 260523A: Global MASTER-Net observations report
  10. GRB 260522A: Fermi GBM Observation
  11. GRB 260522B: NuSTAR detection of prompt emission
  12. EP260518a (AT2026ndp): LCO observations and Gemini-South Redshift z = 2.28
  13. GRB 260522A: GOTO optical upper limit
  14. Fermi GRB 260522A: Global MASTER-Net observations report
  15. GRB 260522A: Fermi-LAT detection
  16. GRB 260519C: SVOM/GRM observation
  17. GRB 260511A: iTelescope T-75 optical detection
  18. GRB 260520B: SVOM/GRM observation
  19. GRB 260411B: TERI Gamma-ray detection
  20. GRB 260407A: TERI Gamma-ray detection
  21. GRB 260307A: TERI Gamma-ray detection
  22. GRB 260225D: TERI Gamma-ray detection
  23. GRB 251118A: TERI Gamma-ray detection
  24. GRB 251113A: TERI Gamma-ray detection
  25. GRB 260428A: TERI Gamma-ray detection
  26. Konus-Wind detection of GRB 260519C
  27. GRB 260509A: SVOM/ECLAIRs refined analysis
  28. GRB 260519C: NuSTAR detection of prompt emission
  29. Konus-Wind detection of GRB 260518A
  30. GRB 260516D: SVOM/ECLAIRs refined analysis
  31. GRB 260515A: SVOM/ECLAIRs refined analysis
  32. GRB 260421B: radio detection with the VLA
  33. GRID detection of GRB 260511A
  34. GRB 260509A: CrAO ZTSh optical upper limit (Duplicate Submission)
  35. GRB 260509A: CrAO ZTSh optical upper limit
  36. GRB 260516D: EP-FXT follow-up observation
  37. GRB 260516D: GOTO optical counterpart detection
  38. GRB 260516D: LCO optical observations
  39. GRB 260515A: further Liverpool Telescope observations
  40. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  41. GRB 260516D: GTC/OSIRIS+ spectroscopic redshift z = 1.801
  42. GRB 260516D: GROWTH-India Telescope optical detection
  43. GRB 260516D: SVOM/VT optical bright candidate
  44. GRB 260515A: CrAO ZTSh BVRI optical observations
  45. Fermi GRB 260516C: Global MASTER-Net observations report
  46. Konus-Wind detection of GRB 260515A
  47. GRB 260515A: Liverpool Telescope optical detection
  48. GRB 260515A: LCO optical counterpart detection
  49. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  50. GRB 260515A: EP-FXT follow-up observation
  51. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  52. EP260514a: NOT optical counterpart confirmation
  53. EP260514a: TRT optical counterpart candidate
  54. EP260514a: SVOM/VT optical candidate
  55. Fermi GRB 260516B: Global MASTER-Net observations report
  56. GRB 260515A: SVOM/VT optical observations
  57. GRB 260515A: OHP/T193 optical observations
  58. EP260514a: COLIBRÍ optical upper limits
  59. GRID detection of GRB 260507A
  60. GRB 260515A: GTC/OSIRIS+ spectroscopic redshift z = 0.764
  61. GRB 260515A: LCO optical observations
  62. SVOM GRB 260515A: Global MASTER-Net observations report
  63. GRB 260515A: NOT optical observations.
  64. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  65. GRB 260515A: SVOM/VT optical candidate from VHF data
  66. GRB 260515A: JinShan optical counterpart candidate
  67. GRB 260510C: Glowbug gamma-ray detection
  68. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  69. EP260514a: GROWTH-India Telescope optical upper limit
  70. GRB 260511B: NOT optical observations
  71. Konus-Wind detection of GRB 260512A
  72. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  73. GRB 260511B: GMG Optical Upper Limit
  74. EP260514a: Global MASTER-Net observations report
  75. EP260512a: LCO optical upper limits
  76. IPN triangulation of GRB 260512A
  77. GRB 260511B: Mephisto multi-band optical followup
  78. Fermi GRB 260514A: Global MASTER-Net observations report
  79. GRB 260512A: AstroSat CZTI detection
  80. EP260512a: EP-FXT follow-up observation
  81. EP260507a: Xinglong Schmidt optical counterpart detection
  82. EP260512a: Global MASTER-Net observations report
  83. Fermi GRB 260513A: Global MASTER-Net observations report
  84. Fermi GRB 260512A: Global MASTER-Net observations report
  85. GRB 260511B: further SAO RAS optical observations
  86. GRB 260509A: SVOM/VT optical observations
  87. Konus-Wind detection of GRB 260511B
  88. EP260512a: COLIBRÍ optical upper limits
  89. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  90. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  91. GRB 260512A: NuSTAR detection of prompt emission
  92. GRB 260509A: Infrared J and Hs observations with MDM/MIRAGE
  93. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  94. EP260507a: Infrared J and Hs upper limits with MDM/MIRAGE
  95. GRB 260511A: Glowbug gamma-ray detection
  96. Konus-Wind detection of GRB 260511A
  97. MASS-Cube (GRID 2.0) detection of GRB 260511A
  98. MASS-Cube (GRID 2.0) detection of GRB 260507A
  99. GRB 260511B: SAO RAS optical observations
  100. GRB 260510D: Glowbug gamma-ray detection of a likely short burst

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