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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"

16233 results found.

  1. GRB 211225A: MITSuME Akeno optical upper limits
  2. GRB 211211A: observations with the 3.6m Devasthal Optical Telescope
  3. GRB 211223C: BOOTES-4/MET optical upper limit
  4. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  5. GRB 211221A: BOOTES-4/MET optical upper limit
  6. GRB 211218A: MITSuME Akeno optical upper limits
  7. GRB 211221A: MeerLICHT optical limits
  8. GRB 211221A: NOT optical limits
  9. GRB 211211A: MMT/MMIRS Observations Indicate Fading of K-band Source
  10. GRB 211211A: TNG NIR observations
  11. GRB 211211A - Gemini K-band detection
  12. GRB 211211A: SAO RAS optical observations
  13. GRB 211211A: AbAO optical observations
  14. GRB 211211A: GMG upper limit
  15. GRB 211211A: Further observations from CAFOS/2.2m CAHA
  16. GRB 211211A: HCT and GIT optical follow up observations
  17. GRB 211211A: Swift/UVOT detection
  18. GRB 211211A: NOT optical spectroscopy
  19. GRB 211211A: Afterglow detection from CAFOS/2.2m CAHA
  20. GRB 211211A: MITSuME Akeno optical observation
  21. GRB 211211A: LCO Optical Observations
  22. GRB 211211A: Nanshan/NEXT optical observations
  23. GRB 211211A: KAIT Optical Afterglow Candidate
  24. GRB 211130A: MeerLICHT identification of possible afterglow candidate
  25. Fermi-LAT Gamma-ray Observations of IceCube-211208A
  26. GRB 211207A: VLT/X-shooter redshift
  27. GRB 211207A: Swift detection of a burst with an optical counterpart
  28. GRB 211129A: Swift/UVOT Upper Limits
  29. GRB 211106A: HST Observations
  30. GRB 211106A: Chandra Observations
  31. GRB 211129A: Nanshan/NEXT optical upper limit
  32. GRB 211129A: MITSuME Akeno optical upper limits
  33. GRB 211023A: Xinglong 2.16m optical observations
  34. GRB 211023A: Xinglong 2.16m optical observations
  35. GRB 211023A: optical observations and photometric evidence of supernova
  36. GRB 211106A: VLT/FORS2 optical observations
  37. GRB 211023A: SAO RAS optical observations
  38. MeerLICHT follow-up of GRB 211106A
  39. GRB 211023A: A BdHN of type I
  40. GRB 211105A: MASTER optical inspection
  41. GRB 211023A: optical detection by SBT in Ondrejov
  42. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  43. GRB 211023B: Subaru optical observation
  44. GRB 211024A: MITSuME Akeno optical observation
  45. GRB 211023B: MITSuME Akeno optical upper limits
  46. GRB 211024B: Optical afterglow observation by Ondrejov D50
  47. GRB 211024A: 1.3m DFOT observations
  48. GRB 211023A: 1.3m DFOT Optical Observations
  49. GRB 2121023B: 6 GHz VLA radio upper limit
  50. GRB 211023A: Terskol optical observations
  51. GRB 211023A: continued Mondy optical observations
  52. GRB 211024A: Swift-XRT source 4 is not an afterglow.
  53. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  54. GRB 211025A: Optical Afterglow Detection
  55. GRB211023A: optical afterglow detection from Konkoly Observatory
  56. GRB 211023A: Mondy optical observations
  57. GRB 211023B: Mondy optical afterglow confirmation
  58. GRB 211023B: Gemini-North Optical Observations
  59. GRB 211023B: LDT Optical Afterglow Detection
  60. GRB 211024B: CAHA 2.2m Detection; ultra-long GRB?
  61. Possible Short GRB 211023B: CAHA 2.2m Detection
  62. GRB 211023A: 1.5m OSN optical observation
  63. GRB 210610B: Sintesz-Newton/CrAO optical observations
  64. GRB 211024B: Nanshan/NEXT optical afterglow detection
  65. GRB 211023A: MASTER OT J045237.07+851925.2 - optical counterpart discovery
  66. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  67. GRB 211023B: RATIR Optical and NIR Upper Limits
  68. GRB 211023B: TSHAO optical observation
  69. GRB 211023B: Swift detection of a possibly short burst with an optical counterpart
  70. BepiColombo MGNS joins the IPN
  71. Swift trigger 1078701: MITSuME Akeno optical upper limits
  72. GRB 210919A: LDT optical observations and candidate host galaxies
  73. IceCube-20210922A: No optical counterparts found by MITSuME observations
  74. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  75. IceCube-20210922A: DESNU Optical counterpart candidate from 5 nights of DECam observations
  76. IceCube-210922A: DESI Observations
  77. GRB 210928A: Kinder SLT-40cm optical limits
  78. Swift GRB211001.03 / trigger 1076121 : MASTER OT retraction
  79. GRB 210930A: CAHA 2.2m telescope optical limit
  80. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  81. Swift GRB211001.03: Global MASTER-Net OT detection
  82. GRB 210930A: Swift/UVOT Upper Limits
  83. GRB 210919A: iTelescope T-11 upper limits
  84. IceCube-210922A: JCMT/SCUBA2 observations
  85. GRB 210912A: LBT optical observations
  86. GRB 210919A: Swift/UVOT Upper Limits
  87. GRB 210919A: LOAO and LSGT optical upper limits
  88. GRB 210919A: MITSuME Akeno optical upper limits
  89. GRB 210919A: NOT upper limits
  90. GRB 210919A: AbAO optical upper limit
  91. GRB 210919A: LCO Optical Upper Limit
  92. GRB 210919A: BOOTES-2/TELMA optical upper limit
  93. GRB 210912A: BOOTES-5/JGT optical afterglow candidate (Correction to GCNC 30823)
  94. GRB 210912A: Tautenburg observations
  95. GRB 210912A: Swift/UVOT Detection
  96. GRB 210912A: Mondy optical afterglow confirmation
  97. GRB 210912A: BOOTES-5/JGT optical afterglow candidate
  98. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  99. GRB 210905A: Swift/UVOT Upper Limits
  100. GRB 210905A: ATCA detection

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