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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"

16272 results found.

  1. GRB 220107A: AbAO and Terskol optical observations
  2. GRB 220107B: MITSuME Akeno optical upper limits
  3. GRB 220107B: Nanshan/NEXT optical upper limits and host galaxy candidate
  4. GRB 220107A: Nanshan/NEXT optical observations
  5. GRB 220107A: Swift/UVOT Detection
  6. GRB 220107A: MITSuME Akeno optical observation
  7. GRB 220101A: Tautenburg observations
  8. GRB 220101A: Continued Mondy optical observations
  9. GRB 220101A: continued 1.3m DFOT Optical Observations
  10. GRB 220101A: Mondy optical observations
  11. GRB 220101A: 3rd LCO Optical Observation
  12. GRB 220101A: 2.2m CAHA (+CAFOS) first day optical detection
  13. GRB 220101A: iTelescope optical observations
  14. GRB 211227A: Lijiang 2.4m Telescope Optical Observations
  15. GRB 220101A: VLA detection
  16. GRB 220101A: 1.3m DFOT observations
  17. GRB 220101A: LCO Continued Optical Observations
  18. GRB 211227A: Gemini South Optical Observations
  19. GRB 220101A: TNG NIR afterglow detection
  20. GRB 220101A: ALMA detection
  21. GRB 220101A: LCO Optical Observations
  22. GRB 220101A: Tautenburg observations
  23. GRB 220101A: GMG observation (2nd epoch)
  24. GRB 220101A: OASDG optical observations
  25. GRB 220101A: GMG observation
  26. GRB 220101A: Asiago spectroscopic and photometric detection
  27. GRB220101A: optical afterglow detection from Konkoly Observatory
  28. GRB 220101A: NOT redshift confirmation
  29. GRB 220101A: Liverpool telescope imaging of a high-redshift afterglow
  30. GRB 220101A: THO optical observations
  31. GRB 220101A: Xinglong-2.16m photometry and spectroscopy
  32. GRB 220101A: Swift detection of a burst with a bright optical counterpart
  33. GRB 211229A: Swift-XRT and UVOT observations
  34. GRB 211227A: Swift/UVOT Upper Limits
  35. GRB 211227A: LCO Optical Observations
  36. GRB 211227A: Nanshan/NEXT optical observations and host galaxy candidate
  37. GRB 211227A: BOOTES-2/TELMA optical upper limit
  38. GRB 211221A: Swift/UVOT Upper Limits
  39. IceCube-20211216B: observations of SN2021gpw in the errorbox of the neutrino trigger
  40. GRB 211225A: MITSuME Akeno optical upper limits
  41. GRB 211211A: observations with the 3.6m Devasthal Optical Telescope
  42. GRB 211223C: BOOTES-4/MET optical upper limit
  43. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  44. GRB 211221A: BOOTES-4/MET optical upper limit
  45. GRB 211218A: MITSuME Akeno optical upper limits
  46. GRB 211221A: MeerLICHT optical limits
  47. GRB 211221A: NOT optical limits
  48. GRB 211211A: MMT/MMIRS Observations Indicate Fading of K-band Source
  49. GRB 211211A: TNG NIR observations
  50. GRB 211211A - Gemini K-band detection
  51. GRB 211211A: SAO RAS optical observations
  52. GRB 211211A: AbAO optical observations
  53. GRB 211211A: GMG upper limit
  54. GRB 211211A: Further observations from CAFOS/2.2m CAHA
  55. GRB 211211A: HCT and GIT optical follow up observations
  56. GRB 211211A: Swift/UVOT detection
  57. GRB 211211A: NOT optical spectroscopy
  58. GRB 211211A: Afterglow detection from CAFOS/2.2m CAHA
  59. GRB 211211A: MITSuME Akeno optical observation
  60. GRB 211211A: LCO Optical Observations
  61. GRB 211211A: Nanshan/NEXT optical observations
  62. GRB 211211A: KAIT Optical Afterglow Candidate
  63. GRB 211130A: MeerLICHT identification of possible afterglow candidate
  64. Fermi-LAT Gamma-ray Observations of IceCube-211208A
  65. GRB 211207A: VLT/X-shooter redshift
  66. GRB 211207A: Swift detection of a burst with an optical counterpart
  67. GRB 211129A: Swift/UVOT Upper Limits
  68. GRB 211106A: HST Observations
  69. GRB 211106A: Chandra Observations
  70. GRB 211129A: Nanshan/NEXT optical upper limit
  71. GRB 211129A: MITSuME Akeno optical upper limits
  72. GRB 211023A: Xinglong 2.16m optical observations
  73. GRB 211023A: Xinglong 2.16m optical observations
  74. GRB 211023A: optical observations and photometric evidence of supernova
  75. GRB 211106A: VLT/FORS2 optical observations
  76. GRB 211023A: SAO RAS optical observations
  77. MeerLICHT follow-up of GRB 211106A
  78. GRB 211023A: A BdHN of type I
  79. GRB 211105A: MASTER optical inspection
  80. GRB 211023A: optical detection by SBT in Ondrejov
  81. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  82. GRB 211023B: Subaru optical observation
  83. GRB 211024A: MITSuME Akeno optical observation
  84. GRB 211023B: MITSuME Akeno optical upper limits
  85. GRB 211024B: Optical afterglow observation by Ondrejov D50
  86. GRB 211024A: 1.3m DFOT observations
  87. GRB 211023A: 1.3m DFOT Optical Observations
  88. GRB 2121023B: 6 GHz VLA radio upper limit
  89. GRB 211023A: Terskol optical observations
  90. GRB 211023A: continued Mondy optical observations
  91. GRB 211024A: Swift-XRT source 4 is not an afterglow.
  92. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  93. GRB 211025A: Optical Afterglow Detection
  94. GRB211023A: optical afterglow detection from Konkoly Observatory
  95. GRB 211023A: Mondy optical observations
  96. GRB 211023B: Mondy optical afterglow confirmation
  97. GRB 211023B: Gemini-North Optical Observations
  98. GRB 211023B: LDT Optical Afterglow Detection
  99. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  100. Possible Short GRB 211023B: CAHA 2.2m Detection

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