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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"

27211 results found.

  1. GRB 261017A: SVOM/GRM observation
  2. GRB 261021A: Fermi GBM Final Real-time Localization
  3. EP261015a: AZT-20 Assy-Turgen optical observations
  4. GRB 261020A: Fermi GBM Observation
  5. EP261015a: Wendelstein 43 cm optical observations
  6. EP261007b: Further EP-FXT follow-up observations
  7. GRB 261017A: COLIBRÍ optical upper limit
  8. GRB 261020A: MAXI GSC detection
  9. GRB 261020A: Fermi GBM Final Real-time Localization
  10. EP261015a: COLIBRÍ optical observations of a rebrightening
  11. GRB 261019A: Fermi GBM Final Localization
  12. GRB 261017A: Possible Swift/UVOT Detection
  13. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  14. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  15. GRB 261017A: Swift-BAT refined analysis
  16. EP261015b: NOT Optical Observations
  17. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  18. EP261015c: refined analysis of the EP-FXT observation favors a stellar flare interpretation
  19. GRB 261017A : MITSuME Akeno optical upper limits
  20. GRB 261017A: Swift-XRT refined Analysis
  21. GRB 261017A: Fermi GBM Observation
  22. GRB 261017A: Swift detection of a burst
  23. GRB 261017A: Fermi GBM Final Real-time Localization
  24. EP261015b: Refined analysis of EP-FXT observations
  25. EP261015a: refined analysis of EP-FXT observations
  26. GRB 261011A: 1.3m DFOT optical upper limit
  27. EP261015a: SVOM/VT optical observation
  28. EP241111a and EP250125a: Upper limits from SVOM/GRM Observations
  29. EP261015a: COLIBRÍ optical observations
  30. EP261015c: Einstein Probe detection of a fast X-ray transient
  31. EP261015b: Einstein Probe detection of an X-ray transient
  32. EP261015a: Einstein Probe detection of a fast X-ray transient
  33. EP261015a (WXT 11900947714): Possible optical counterpart from NOT and LCO
  34. The EP-WXT trigger 01709321333 is likely a flaring star
  35. GRB 261010A: LBT tentative near-infrared detection
  36. GRB 261008A: SVOM/GRM observation
  37. GRB 261009A: GECAM-B detection of a burst
  38. GRB 261013A: Fermi GBM Final Real-time Localization
  39. GRB 261011A: Later-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  40. GRID detection of GRB 261010A
  41. GRB 261011A: GECAM-B observation
  42. GRB 261011B: GECAM-B observation
  43. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope
  44. GRB 261010A: Swift-XRT refined Analysis
  45. GRB 261011A: Swift-XRT refined Analysis
  46. GRB 261011A: Swift-BAT refined analysis
  47. MAXI GRB261012.23: Global MASTER-Net observations report
  48. GRB 261011A: REM optical/NIR observations
  49. Konus-Wind detection of GRB 261010A
  50. GRB 261011A: SOAR optical afterglow observations at ~17 hours
  51. EP261006a: 10 GHz VLA observations
  52. GRB 261010A: Swift-BAT refined analysis
  53. GRB 261011A : MITSuME Akeno optical afterglow candidate detection
  54. GRB 261011A: Optical followup from Sichuan South Observatory
  55. GRB 261011A: GMG Optical Observation
  56. GRB 261011A: Liverpool Telescope optical observations
  57. GRB 261011A: J-band observations by the SYSU 80cm infrared telescope
  58. GRB 261010A: NOT confirmation of the optical afterglow
  59. GRB 261010A: Fermi GBM Observation
  60. GRB 261011B: Fermi GBM Final Localization
  61. GRB 261011A: continued LCO optical observations
  62. EP261007b: Global MASTER-Net observations report
  63. GRB 261011A: GROWTH-India Telescope optical observations
  64. GRB 261011A: Luminance-band upper limit from a 28cm telescope in Chengde
  65. Swift GRB 261011A: Global MASTER-Net observations report
  66. GRB 261011A: Optical follow-up observations with Kinder
  67. GRB 261011A: SVOM/C-GFT optical observations
  68. EP261007b: Second EP-FXT follow-up observation and a possible X-ray counterpart to the optical transient
  69. GRB 261011A: LCO optical observations
  70. GRB 261011A: SVOM/VT optical observation from VHF data
  71. GRB 261011A: LCO optical observations
  72. GRB 261011A: TRT optical afterglow detection
  73. GRB 261011A: GOTO optical counterpart detection
  74. GRB 261011A: Swift detection of an unusual burst
  75. GRB 261011A: SVOM detection of a long bright burst
  76. EP261010a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  77. GRB 261010A: possible optical afterglow detected with the 1.5m OSN
  78. GRB 261010A: NOT possible optical counterpart
  79. GRB 261010A: Swift detection of a burst
  80. GRB 261010A: Fermi GBM Final Real-time Localization
  81. EP261006a: Kilonova-Catcher optical follow-up and detection
  82. GRB 261001A: SVOM/GRM observation
  83. EP261010a: SVOM/VT optical upper limits
  84. EP261006a: Liverpool Telescope optical follow-up
  85. EP261010a: NOT optical upper limits
  86. EP261010a: Global MASTER-Net observations report
  87. EP261010a Einstein Probe detection of an X-ray transient
  88. GRB 261009A: Fermi GBM Final Real-time Localization
  89. GRB261007A: Lesedi optical afterglow detection
  90. EP261006a: Xinglong 2.16m/BFOSC optical follow-up observations
  91. EP261007b: SVOM/ECLAIRs Upper Limit
  92. GRB 261008A: GECAM-B observation
  93. EP261007b: J-band upper limit by SYSU 80cm infrared telescope
  94. EP261007b: Refined analysis of the EP-WXT and autonomous EP-FXT observations
  95. GRB 261007A: SVOM/ECLAIRs refined analysis
  96. EP261007b: SVOM/VT optical detection of the NOT transient
  97. GRB 261007A / EP261007a: SVOM/GWAC-F60A/B observations
  98. EP261006a / AT 2026aetp: VLT/X-shooter spectroscopic redshift z = 0.1853
  99. GRB 261008A: Fermi GBM Final Real-time Localization
  100. GRB 261007A: NOT optical observations

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