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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"

19701 results found.

  1. GRB 211023A: optical detection by SBT in Ondrejov
  2. GRB 211023B: Subaru optical observation
  3. GRB 211024A: MITSuME Akeno optical observation
  4. GRB 211023B: MITSuME Akeno optical upper limits
  5. GRB 211024B: Optical afterglow observation by Ondrejov D50
  6. IPN triangulation of GRB 211022A
  7. AMON NuEm-211020A: No Candidate Counterparts from Swift-XRT follow up observations
  8. GRB 211024A: Swift-XRT source 4 is not an afterglow.
  9. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  10. GRB 211024A: Possible afterglow candidate from GIT
  11. GRB211023A: optical afterglow detection from Konkoly Observatory
  12. GRB 211024A: Swift ToO observations
  13. GRB 211023B: Mondy optical afterglow confirmation
  14. GRB 211023B: LDT Optical Afterglow Detection
  15. GRB 211024B: Swift-XRT refined Analysis
  16. GRB 211025A: Swift/UVOT Detection
  17. GRB 211024B: Swift-BAT refined analysis
  18. GRB 210610B: Sintesz-Newton/CrAO optical observations
  19. GRB 211025A: Enhanced Swift-XRT position
  20. GRB 211025A: Swift detection of a burst
  21. GRB 211024B: Nanshan/NEXT optical afterglow detection
  22. GRB 210919A: FORS2/VLT observations
  23. Fermi-LAT Gamma-ray Observations of IceCube-211023A
  24. GRB 211023B: Swift/UVOT Detection
  25. GRB 211023B: RATIR Optical and NIR Upper Limits
  26. GRB 211023B: TSHAO optical observation
  27. GRB 211023B: Swift-XRT refined Analysis
  28. GRB 211023B: Enhanced Swift-XRT position
  29. GRB 211023B: Swift detection of a possibly short burst with an optical counterpart
  30. IPN Triangulation of GRB 210927B
  31. AMON IC_HAWC NuEm-211020A: No neutrino counterpart detected with ANTARES
  32. GRB 211018A: Swift ToO observations
  33. BepiColombo MGNS joins the IPN
  34. IceCube-210922A: Hard X-ray flux limit for JCMT/SCUBA2 source from NuSTAR observations
  35. Swift trigger 1078701: MITSuME Akeno optical upper limits
  36. GRB 210919A: LDT optical observations and candidate host galaxies
  37. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  38. Swift Trigger 1078701 is probably not a GRB
  39. IceCube-20210922A: DESNU Optical counterpart candidate from 5 nights of DECam observations
  40. GRB 210928A: MeerKAT detection
  41. IceCube-210922A: DESI Observations
  42. GRB 210928A: Kinder SLT-40cm optical limits
  43. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  44. GRB 210928A: Swift-XRT refined Analysis
  45. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  46. Swift Trigger 1076121 is not a GRB
  47. GRB 210930A: Swift/UVOT Upper Limits
  48. GRB 210930A: Enhanced Swift-XRT position
  49. GRB 210930A: Swift detection of a burst
  50. Fermi-LAT Gamma-ray Observations of IceCubeCascade-210926A
  51. IPN triangulation of GRB 210925B
  52. GRB 210919A: iTelescope T-11 upper limits
  53. IceCube-210922A: JCMT/SCUBA2 observations
  54. GRB 210919A: Chandra rapid ToO upper limit
  55. IceCube-210922A: No significant detection in HAWC
  56. GRB 210919A: DECam Upper Limits
  57. Fermi-LAT Gamma-ray Observations of IceCube-210922A
  58. GRB 210912A: LBT optical observations
  59. GRB 210919A: Lowell Discovery Telescope upper limits (correction to GCN 30859)
  60. GRB 210919A: Swift/UVOT Upper Limits
  61. GRB 210919A: LOAO and LSGT optical upper limits
  62. GRB 210919A: MITSuME Akeno optical upper limits
  63. GRB 210919A: NOT upper limits
  64. GRB 210919A: AbAO optical upper limit
  65. GRB 210919A: Enhanced Swift-XRT position
  66. GRB 210919A: Swift detection of a short burst
  67. Swift trigger 1073821: detection of IGR J16418-4532
  68. GRB 210912A: BOOTES-5/JGT optical afterglow candidate (Correction to GCNC 30823)
  69. GRB 210812A is not a compelling example of a lensed GRB
  70. GRB 210912A: Tautenburg observations
  71. GRB 210912A: Swift/UVOT Detection
  72. GRB 210912A: Enhanced Swift-XRT position
  73. GRB 210912A: Mondy optical afterglow confirmation
  74. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  75. GRB 210912A: Swift detection of a burst
  76. Fermi trigger No 653084584: Global MASTER-Net observations report
  77. IPN triangulation of a bright burst from SGR 1935+2154
  78. GRB 210826A: further Swift-XRT observations
  79. Swift detection of a burst from SGR Swift J1555.2-5402
  80. Fermi trigger No 652927551: Global MASTER-Net observations report
  81. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  82. GRB 210905A: Swift/UVOT Upper Limits
  83. GRB 210905A, GROND observations
  84. GRB 210905A: Swift-XRT refined Analysis
  85. GRB 210610A: Maidanak and AbAO optical observations
  86. GRB 210905A: REM NIR afterglow detection
  87. GRB 210905A: Enhanced Swift-XRT position
  88. GRB 210901A: Swift/UVOT Upper Limits
  89. GRB 210905A: Swift detection of a burst
  90. GRB 210820A: TSHAO optical upper limit
  91. GRB 210901A: GROND observations
  92. Fermi GBM observation of a burst from SGR J1555.2-5402
  93. GRB 210901A: Enhanced Swift-XRT position
  94. GRB 210901A: Swift detection of a burst
  95. GRB 210827A: BOOTES-5/JGT optical upper limit
  96. GRB 210826A: AstroSat CZTI detection
  97. GRB 210827A: Swift ToO observations
  98. GRB 210820A: CAHA 2.2m Optical Detection
  99. GRB 210824A: Swift/UVOT Upper Limits
  100. GRB 210826A: Swift/UVOT Upper Limits

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