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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"

19663 results found.

  1. Konus-Wind detection of GRB 261017A
  2. GRB 261017A: Possible Swift/UVOT Detection
  3. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  4. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  5. GRB 261017A: Swift-BAT refined analysis
  6. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  7. GRB 261017A : MITSuME Akeno optical upper limits
  8. GRB 261017A: Swift-XRT refined Analysis
  9. GRB 261017A: Nanshan/NEXT optical upper limit
  10. GRB 261017A: Enhanced Swift-XRT position
  11. GRB 261017A: Fermi GBM Observation
  12. GRB 261017A: Swift detection of a burst
  13. GRB 261011A: 1.3m DFOT optical upper limit
  14. GRB 261010A: Pan-STARRS z-band imaging and upper limit
  15. GRB 261010A: LBT tentative near-infrared detection
  16. GRB 261010A: Glowbug gamma-ray detection
  17. GRB 261011A: Later-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  18. GRID detection of GRB 261010A
  19. GRB 261011A: GECAM-B observation
  20. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope
  21. GRB 261010A: Swift-XRT refined Analysis
  22. GRB 261011A: Swift-XRT refined Analysis
  23. GRB 261011A: Enhanced Swift-XRT position
  24. GRB 261011A: 10.4m GTC spectroscopic redshift (z = 2.407)
  25. GRB 261011A: Swift-BAT refined analysis
  26. GRB 261010A: 10.4m GTC spectroscopy of the galaxy 2" from the afterglow
  27. GRB 261011A: REM optical/NIR observations
  28. Konus-Wind detection of GRB 261010A
  29. Konus-Wind detection of GRB 261011A
  30. GRB 261011A: SOAR optical afterglow observations at ~17 hours
  31. GRB 261010A: Swift-BAT refined analysis
  32. GRB 261011A : MITSuME Akeno optical afterglow candidate detection
  33. GRB 261011A: Optical followup from Sichuan South Observatory
  34. GRB 261011A: GMG Optical Observation
  35. GRB 261011A: Liverpool Telescope optical observations
  36. GRB 261011A: J-band observations by the SYSU 80cm infrared telescope
  37. GRB 261010A: NOT confirmation of the optical afterglow
  38. GRB 261010A: Fermi GBM Observation
  39. GRB 261011A: continued LCO optical observations
  40. GRB 261011A: GROWTH-India Telescope optical observations
  41. GRB 261011A: Luminance-band upper limit from a 28cm telescope in Chengde
  42. Swift GRB 261011A: Global MASTER-Net observations report
  43. GRB 261011A: Optical follow-up observations with Kinder
  44. GRB 261011A: SVOM/VT optical observation from VHF data
  45. GRB 261011A: LCO optical observations
  46. GRB 261011A: TRT optical afterglow detection
  47. GRB 261011A: GOTO optical counterpart detection
  48. GRB 261011A: Swift detection of an unusual burst
  49. GRB 261010A: Enhanced Swift-XRT position
  50. GRB 261010A: possible optical afterglow detected with the 1.5m OSN
  51. GRB 261010A: NOT possible optical counterpart
  52. GRB 261010A: Swift detection of a burst
  53. EP261006a: Swift/XRT detection of the fading X-ray counterpart
  54. GRB 261007A: Swift-XRT afterglow detection
  55. GRB 261007A: Swift ToO observations
  56. GRB 261005B: Swift-BAT refined analysis
  57. GRB 261005B: Swift-XRT refined Analysis
  58. GRB 261005B: Swift/UVOT Upper Limits
  59. GRB 261005B: J-band upper limit with WINTER
  60. GRB 261005B: Fermi GBM Observation
  61. GRB 261005B: Enhanced Swift-XRT position
  62. GRB 261005B: Swift detection of a burst
  63. EP#01709320865: Swift-XRT observations
  64. Trigger_21915: Swift ToO observations (retracted)
  65. GRB 260924A: Swift/UVOT UV grism spectrum results
  66. GRB 260925A: Swift-BAT refined analysis
  67. Swift Trigger 1513439: consistent with noise and not astrophysical
  68. GRB 260924A: COLIBRÍ optical observations
  69. GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  70. GRB 260925A: Swift-XRT refined Analysis
  71. Swift Trigger 1513439 is probably not a GRB
  72. GRB 260925A: Swift/UVOT Upper Limits
  73. Konus-Wind detection of GRB 260924A
  74. GRB 260922A: Glowbug gamma-ray detection
  75. GRB 260925A: Enhanced Swift-XRT position
  76. GRB 260925A: COLIBRÍ optical upper limits
  77. GRB 260925A: FRAM-Auger optical limit
  78. GRB 260924A: Ondrejov D50 optical afterglow detection
  79. GRB 260924A: SVOM/GRM observation
  80. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  81. GRB 260925A: Swift detection of a burst
  82. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  83. GRB 260924A: Swift/UVOT Detection
  84. GRB 260924A: Swift-BAT refined analysis
  85. GRB 260924A: NuSTAR detection of prompt emission
  86. GRB 260924A: Swift/UVOT Upper Limits
  87. GRB 260924A: Swift-XRT refined Analysis
  88. Konus-Wind detection of GRB 260922A
  89. GRB 260922A: NuSTAR detection of prompt emission
  90. GRB 260921A: NuSTAR detection of prompt emission
  91. GRB 260921A: SVOM/GRM observation
  92. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  93. GRB 260924A: Fermi GRB Observation
  94. Konus-Wind detection of GRB 260921A (possible merger-origin)
  95. GRB 260924A: Fermi-LAT detection of a bright burst
  96. GRB 260924A: AstroSat CZTI detection
  97. GRB 260924A: NOT optical counterpart confirmation
  98. GRB 260924A: detection of a bright optical afterglow by the 1.5m OSN telescope
  99. GRB 260922A: CALET Gamma-Ray Burst Monitor detection
  100. GRB 260924A: Enhanced Swift-XRT position

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