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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"

19692 results found.

  1. NuEm-210111A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  2. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  3. GRB 210104A: SAO RAS optical observations
  4. GRB 210104A: GMG observations
  5. GRB210104A: VIRT optical transient detection.
  6. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  7. GRB 210102B: further Swift-XRT observations
  8. GRB 210102B: Assy optical afterglow identification
  9. GRB 210104A: iTelescope optical upper limit
  10. GW170817: HST observations at 3.4 years from merger
  11. GRB 210104A: early ATLAS detections of the bright afterglow
  12. GRB 210104B: Swift/UVOT Upper Limits
  13. GRB 210104B: Assy optical upper limit
  14. GRB 210104B: Enhanced Swift-XRT position
  15. GRB 210104A: Nanshan/NEXT optical powerlaw decay
  16. GRB 210104B: Nanshan/NEXT optical upper limit
  17. GRB 210104A: Swift/UVOT Detection
  18. GRB 210104A: Enhanced Swift-XRT position
  19. GRB 210102B: Tiled Swift observations
  20. GRB 210104B: Swift detection of a burst
  21. GRB 210104A: MITSuME Ishigaki optical observation
  22. GRB 210104A: MITSuME Akeno optical observation
  23. GRB 210104A: Swift detection of a burst with a bright optical counterpart
  24. GRB 210102C: Swift-BAT refined analysis
  25. GRB 210102B: Tiled Swift observations
  26. INTEGRAL Weak #8913: AROMA-N Optical Observation
  27. Swift Trigger 1015615 is not a GRB
  28. GRB 201229A: Swift/UVOT Detection
  29. GRB 201216C: TSHAO, Terskol, Mondy optical upper limits
  30. GRB 201227A: Chilescope optical observations, possible optical counterpart
  31. GRB 201227A: GRAWITA VST-ESO PARANAL observations
  32. GRB 201229A: AbAO optical afterglow detection, TSHAO optical upper limit
  33. GRB 201229A: SAO RAS optical observations
  34. GRB 201229A: Nanshan/NEXT optical upper limit
  35. GRB 201229A: Enhanced Swift-XRT position
  36. GRB 201229A: Swift detection of a burst with a possible optical counterpart
  37. GRB 201227A: Tiled Swift observations
  38. GRB 201227A: Swift ToO observations
  39. IPN triangulation of GRB 201227A (short)
  40. ZTF20acozryr/AT2020yxz (GRB 201103B): Maidanak optical observations
  41. GRB 201223A: AROMA-N Optical Observation
  42. GRB 201223A: Swift/UVOT Detection
  43. GRB 201223A: AbAO optical observations
  44. GRB 201223A: Enhanced Swift-XRT position
  45. GRB 201223A: NOT optical upper limit and NEXT powerlaw decay
  46. GRB 201223A: GROWTH-India Telescope (GIT) photometric follow-up.
  47. GRB 201223A: Mondy and Kitab optical observations
  48. GRB 201223A: iTelescope optical afterglow observations
  49. GRB 201223A: MITSuME Akeno optical observation
  50. GRB 201223A: Swift-BAT refined analysis
  51. GRB 201223A: Fermi GBM Detection
  52. GRB 201223A: Nanshan/NEXT early optical afterglow detection
  53. GRB 201223A: Swift detection of a burst with a bright optical counterpart
  54. Swift-XRT observations of Icecube 201222A
  55. IceCube-201222A: No significant detection in HAWC
  56. IceCube-201221A: No significant detection in HAWC
  57. GRB 201221A: REM early-time afterglow detection
  58. GRB 201221D: 3.6m DOT optical observations
  59. GRB 201221D: SMA submm observation
  60. GRB 201221D: Fermi GBM detection
  61. GRB 201216A - further Swift-XRT observations
  62. Fermi-LAT Gamma-ray Observations of IceCube-201221A
  63. IceCube-201222A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  64. GRB 201221D: Swift/UVOT Upper Limits
  65. GRB 201221D: FRAM-ORM optical limit
  66. GRB 201221D: Enhanced Swift-XRT position
  67. GRB 201221D: Nanshan/NEXT early optical upper limit
  68. GRB 201221D: candidate optical counterpart from the NOT
  69. GRB 201221D: Swift detection of a bright short burst
  70. GRB 201221A: Swift/UVOT Upper Limits
  71. Swift Trigger 1014012: possible GRB 201221C
  72. GRB 201221A: Enhanced Swift-XRT position
  73. IceCube-201221A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  74. GRB 201221A: VLT/X-shooter afterglow discovery and spectroscopic redshift z = 5.7
  75. GRB 201221A: Swift detection of a burst
  76. GRB 201209A: Mondy optical observations, afterglow confirmation
  77. GRB 201214A: TSHAO optical upper limit
  78. GRB 201214A: Swift-XRT afterglow detection
  79. GRB 201214A: 1.3m DFOT, optical upper limits
  80. IPN triangulation of GRB 201218A
  81. GRB201216C: No significant detection in HAWC
  82. GRB 201216C: Liverpool Telescope First Hour Observations
  83. GRB 201216C: Fermi-LAT upper limit
  84. GRB 201216C: AstroSat CZTI detection
  85. GRB 201216C: Swift/UVOT Upper Limits
  86. GRB 201216A: Swift-XRT observations
  87. GRB 201216C: Enhanced Swift-XRT position
  88. GRB 201216C: VLT afterglow candidate discovery
  89. GRB 201216A: Swift ToO observations
  90. GRB 201216C: Swift-XRT observations
  91. GRB 201214B: MITSuME Akeno optical upper limits
  92. Chandra observations of GW170817 at ~3.3 years since merger (Full report)
  93. GRB 201214B: Lowell Discovery Telescope optical observations
  94. GRB 201214B: Swift ToO observations
  95. IceCube-201209: No significant detection in HAWC
  96. Potential X-ray KN afterglow from Chandra observations of GW170817 ~3.3 years since merger (3 Epochs of 4)
  97. GRB 201214A: Swift ToO observations
  98. GRB 201203A: Zeiss-1000 (Koshka observatory) optical upper limit
  99. GRB 201203A: 1.3m DFOT, optical upper limits
  100. GRB 200826A: GMOS-N detected source magnitude (Correction)

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