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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').
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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"

16152 results found.

  1. ZTF22aaajecp/AT2022cmc: VLA radio detection
  2. ZTF22aaajecp/AT2022cmc: Zwicky Transient Facility discovery of a fast and red optical transient
  3. GRB 220210A: Mondy, AbAO and Terskol optical upper limits
  4. GRB 220210A: 1.5m OSN optical upper limit
  5. GRB 220210A: BOOTES-5/JGT optical afterglow candidate discarded
  6. GRB 220210A: BOOTES-5/JGT optical afterglow candidate
  7. GRB 210919A: Maidanak optical observations
  8. IceCube-211208A: the optical observation of the candidate PKS0735+178
  9. GRB 220117A, GROND observations
  10. GRB 220117A: Terskol and AbAO optical upper limits
  11. GRB 220118A: TARGET optical upper limit
  12. GRB 220117B: TARGET optical upper limit
  13. GRB 220118A: COATLI Optical Observations
  14. GRB 220101A: KAO optical-R observation
  15. GRB 211221A: No V & R detection, KAO telescope
  16. GRB 220118A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  17. GRB 220118A: GIT optical observations
  18. GRB 220118A: MITSuME Akeno optical observation
  19. GRB 220118A: Swift detection of a burst with an optical counterpart
  20. GRB 220117A: MITSuME Akeno optical upper limits
  21. GRB 220117B: Swift/UVOT Upper Limits
  22. GRB 220117A: Swift/UVOT Upper Limits
  23. GRB 220117A: LCO Optical Observations
  24. GRB 220117A: VLT/X-shooter optical afterglow and redshift
  25. GRB 220117B: Nanshan/NEXT optical upper limit
  26. GRB 220117B: MITSuME Akeno optical upper limits
  27. GRB 220101A: TSHAO optical observation, Terskol, AbAO upper limits
  28. GRB 220117A: Nanshan/NEXT optical observations and a nearby PanSTARRS source
  29. GRB 220101A: The most powerful GRB and BDHN I in 26 years
  30. GRB 220101A: continued 1.3m DFOT optical observations of a high-redshift afterglow
  31. GRB 220107A: SAO RAS optical observations
  32. GRB 220107A: further SAO RAS optical observations
  33. GRB 220101A: Additional Liverpool telescope photometry
  34. GRB 220107A: 6m BTA spectroscopic redshift
  35. GRB 220107A: SAO RAS optical observations
  36. GRB 220101A: SAO RAS optical observations
  37. GRB 220107A: AbAO and Terskol optical observations
  38. GRB 220107B: MITSuME Akeno optical upper limits
  39. GRB 220107B: Nanshan/NEXT optical upper limits and host galaxy candidate
  40. GRB 220107A: Nanshan/NEXT optical observations
  41. GRB 220107A: Swift/UVOT Detection
  42. GRB 220107A: MITSuME Akeno optical observation
  43. GRB 220101A: Tautenburg observations
  44. GRB 220101A: Continued Mondy optical observations
  45. GRB 220101A: continued 1.3m DFOT Optical Observations
  46. GRB 220101A: Mondy optical observations
  47. GRB 220101A: 3rd LCO Optical Observation
  48. GRB 220101A: 2.2m CAHA (+CAFOS) first day optical detection
  49. GRB 220101A: iTelescope optical observations
  50. GRB 211227A: Lijiang 2.4m Telescope Optical Observations
  51. GRB 220101A: VLA detection
  52. GRB 220101A: 1.3m DFOT observations
  53. GRB 220101A: LCO Continued Optical Observations
  54. GRB 211227A: Gemini South Optical Observations
  55. GRB 220101A: TNG NIR afterglow detection
  56. GRB 220101A: ALMA detection
  57. GRB 220101A: LCO Optical Observations
  58. GRB 220101A: Tautenburg observations
  59. GRB 220101A: GMG observation (2nd epoch)
  60. GRB 220101A: OASDG optical observations
  61. GRB 220101A: GMG observation
  62. GRB 220101A: Asiago spectroscopic and photometric detection
  63. GRB220101A: optical afterglow detection from Konkoly Observatory
  64. GRB 220101A: NOT redshift confirmation
  65. GRB 220101A: Liverpool telescope imaging of a high-redshift afterglow
  66. GRB 220101A: THO optical observations
  67. GRB 220101A: Xinglong-2.16m photometry and spectroscopy
  68. GRB 220101A: Swift detection of a burst with a bright optical counterpart
  69. GRB 211229A: Swift-XRT and UVOT observations
  70. GRB 211227A: Swift/UVOT Upper Limits
  71. GRB 211227A: LCO Optical Observations
  72. GRB 211227A: Nanshan/NEXT optical observations and host galaxy candidate
  73. GRB 211227A: BOOTES-2/TELMA optical upper limit
  74. GRB 211221A: Swift/UVOT Upper Limits
  75. IceCube-20211216B: observations of SN2021gpw in the errorbox of the neutrino trigger
  76. GRB 211225A: MITSuME Akeno optical upper limits
  77. GRB 211211A: observations with the 3.6m Devasthal Optical Telescope
  78. GRB 211223C: BOOTES-4/MET optical upper limit
  79. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  80. GRB 211221A: BOOTES-4/MET optical upper limit
  81. GRB 211218A: MITSuME Akeno optical upper limits
  82. GRB 211221A: MeerLICHT optical limits
  83. GRB 211221A: NOT optical limits
  84. GRB 211211A: MMT/MMIRS Observations Indicate Fading of K-band Source
  85. GRB 211211A: TNG NIR observations
  86. GRB 211211A - Gemini K-band detection
  87. GRB 211211A: SAO RAS optical observations
  88. GRB 211211A: AbAO optical observations
  89. GRB 211211A: GMG upper limit
  90. GRB 211211A: Further observations from CAFOS/2.2m CAHA
  91. GRB 211211A: HCT and GIT optical follow up observations
  92. GRB 211211A: Swift/UVOT detection
  93. GRB 211211A: NOT optical spectroscopy
  94. GRB 211211A: Afterglow detection from CAFOS/2.2m CAHA
  95. GRB 211211A: MITSuME Akeno optical observation
  96. GRB 211211A: LCO Optical Observations
  97. GRB 211211A: Nanshan/NEXT optical observations
  98. GRB 211211A: KAIT Optical Afterglow Candidate
  99. GRB 211130A: MeerLICHT identification of possible afterglow candidate
  100. Fermi-LAT Gamma-ray Observations of IceCube-211208A

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