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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"

28117 results found.

  1. Fermi GRB 260310B: Global MASTER-Net observations report
  2. Fermi GRB 260310A: Global MASTER-Net observations report
  3. GRB 260208A: radio detection with the VLA
  4. GRB 260307A: Glowbug gamma-ray detection
  5. Fermi GBM Sub-Threshold Detection of GRB 260307B
  6. GRB 260307B: Mephisto optical upper limits
  7. GRB 260307B: possible NOT optical counterpart
  8. GRB 260307B: SVOM/VT upper limit with X band data analysis
  9. Fermi GRB 260307A: Global MASTER-Net observations report
  10. GRB260307B: GROWTH-India Telescope optical upper limit
  11. GRB 260307B: SVOM/VT optical candidate
  12. GRB 260307B: SVOM/C-GFT upper limit
  13. GRB 260307B: SVOM detection of a burst
  14. EP260306a: refined analysis of the EP-WXT and EP-FXT observations
  15. GRB 260207A: TESS Detection and Possible VLA Counterpart
  16. EP260302a: SVOM/VT optical observation
  17. EP260306a: Gemini-North redshift z = 4.773
  18. EP260306a: SVOM/VT optical observation
  19. EP260302a: Gemini-South redshift z = 1.535
  20. EP260306a: COLIBRÍ optical observations of the fading and red counterpart
  21. EP260306a: Einstein Probe detection of an X-ray transient
  22. EP260302a: Optical afterglow rebrightening
  23. GRB 260228A: further EP-FXT observations and X-ray afterglow confirmation
  24. GRB 260303A: 1.3m DFOT optical upper limit
  25. Fermi GRB 260305A: Global MASTER-Net observations report
  26. GRB 260303B: AstroSat CZTI detection
  27. GRB 260303A: SVOM/VT optical observations
  28. GRB 260303A: J-band observations with WINTER
  29. GRB 260303B: NuSTAR detection of prompt emission
  30. EP260302a: Global MASTER-Net observations report
  31. Fermi GRB 260303B: Global MASTER-Net observations report
  32. GRB 260303B: BALROG localization (Fermi Trigger 794237065 / GRB 260303559)
  33. EP260302a: analysis of the follow-up EP-FXT observation
  34. EP260302a: LCO observations
  35. EP260302a: BOOTES-7 optical counterpart detection at early times
  36. GRB 260303A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  37. GRB 260303A: SVOM detection of a burst
  38. GRB 260228A: EP-FXT follow-up observation
  39. EP260302a: Einstein Probe detection of an X-ray transient
  40. The EP-WXT trigger 01709258736: Las Cumbres discovery of the optical counterpart
  41. GRB 251130B: TERI Gamma-ray detection
  42. GRB 260208A: TERI Gamma-ray detection
  43. EP260227a: Mondy optical observations
  44. GRB 260228A: CAHA 2.2m telescope optical upper limit
  45. GRB 260228A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  46. EP260227a: Mephisto optical detection
  47. EP-WXT trigger 01709258652: 50cm Telescope multi-band observations
  48. EP260227a: SVOM/VT optical observation
  49. GRB 260228A: SVOM/VT optical upper limits
  50. GRB 260225D: SVOM/GRM observation
  51. EP260227A: 3.6m DOT optical afterglow detection
  52. GRB 260225B: SVOM/GRM observation
  53. EP260227a: Liverpool Telescope optical observations
  54. EP260227a: LCOGT Optical Observations
  55. GRB 260226A: Asiago r-band upper limit
  56. EP260227a: Liverpool Telescope observations
  57. EP260227a: COLIBRÍ optical observations
  58. EP260227a: NOT optical observations
  59. EP260227a: Global MASTER-Net observations report
  60. EP260227a: Einstein Probe detection of an X-ray transient and refined analysis
  61. The EP-WXT trigger 01709258681 (EP260227a?): Las Cumbres follow-up observation of the optical counterpart
  62. EP/WXT trigger 01709258681 (EP260227a?): LCO candidate afterglow
  63. GRB 260223A: 7DT detection and Medium-band SED of Afterglow
  64. EP260214a: VLT/FORS2 optical observations
  65. GRB 260225A: WINTER J-band upper limit
  66. GRB 260226A: COLIBRÍ optical upper limits
  67. GRB 260226A: LCOGT Optical Upper Limit
  68. EP-WXT trigger 01709258652: SVOM/C-GFT confirmation of a stellar flare
  69. GRB 260225D: Glowbug gamma-ray detection of a likely short burst
  70. GRB 260226A: Glowbug gamma-ray detection
  71. GRB 260226A: NuSTAR detection of bright prompt emission
  72. GRB 260226A : GROWTH-India Telescope optical observations
  73. GRB 260226A: LAST optical upper limit
  74. GRB 260226A: Fermi GBM observation
  75. LAT GRB260226.44: Global MASTER-Net observations report
  76. Fermi GRB 260226A: Global MASTER-Net observations report
  77. GRB 260226A: AstroSat CZTI detection of bright long burst
  78. GRB 260226A???: BALROG localization (Fermi Trigger 793795080 / GRB 260226443)
  79. EP260224a: LCO optical upper limits
  80. GRB 260225A: EP-FXT follow-up observation
  81. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) Detection of an Optical Counterpart Candidate
  82. GRB 260223A: Fermi GBM Observation
  83. GRB 260225A: SVOM/VT optical upper limits
  84. EP260223a: Liverpool Telescope upper limits
  85. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  86. EP260224a: Einstein Probe detection of an X-ray transient
  87. EP 260225.148: COLIBRÍ Confirmation of flaring star
  88. EP260223a: Xinglong optical upper limit
  89. GRB 260223A: Glowbug gamma-ray detection
  90. EP260213a: Mephisto optical upper limits
  91. GRB 260223A: COLIBRÍ optical afterglow decay confirmation
  92. sb26021801: SVOM/C-GFT upper limit
  93. EP260223a: COLIBRÍ optical upper limits
  94. EP260223a: Einstein Probe detection of an X-ray transient
  95. GRB 260223A: SVOM/GRM observation
  96. GRB 260223A: COLIBRÍ further optical observations and a brightening
  97. EP260221a: Optical upper limit with Kinder observations
  98. GRB 260223A: COLIBRÍ optical observations
  99. GRB 260223A: DDOTI Optical Candidate
  100. GRB 260223A: BALROG localization (Fermi Trigger 793512674 / GRB 260223174)

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