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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16152 results found.

  1. GRB 220813A: Swift detection of a burst with an optical counterpart
  2. GRB 220810A: Swift-XRT observations
  3. GRB 220810A: MeerLICHT detection of two afterglow candidates
  4. GRB 220730A: Swift/UVOT Upper Limits
  5. GRB 220715B: VIRT Optical Upper Limit
  6. GRB 220715B: Swift/UVOT Upper Limits
  7. GRB 220715B: BOOTES-network optical upper limits
  8. GRB 220714B: LCO Optical Observations
  9. GRB 220710A: Swift/UVOT Upper Limits
  10. GRB 220711B, GROND observations
  11. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  12. GRB 220711B: GIT optical upper limits
  13. GRB 220712B: NOT optical afterglow confirmation
  14. GRB 220711B: Swift/UVOT Upper Limits
  15. GRB 220711B: NOT optical observations
  16. GRB 220711B: LCO Optical Upper Limits
  17. GRB 220708B: GIT optical upper limits
  18. GRB 220708B: T193-OHP optical upper limit
  19. IceCube-220624A: Classification of AT2022nit as a type Ia supernova and AT2021bei as an AGN
  20. GRB 220708B: Nanshan/NEXT optical upper limits
  21. GRB 220708A: Swift/UVOT Upper Limits
  22. GRB 220706A: Swift/UVOT Upper Limits
  23. GRB 220708A: BOOTES-5/JGT early optical upper limit
  24. GRB 220706A: LCO Optical Upper Limits
  25. GRB 220627A: ATCA detection of radio counterpart
  26. GRB 220706A, GROND observations
  27. GRB 220706A: Optical observations from NOT
  28. GRB 220706A: Nanshan/NEXT optical upper limits
  29. GRB 220706A: Zadko observatory - Gingin optical observations
  30. GRB220408A: VIRT Optical Upper Limit
  31. GRB220412A: VIRT Optical Upper Limit
  32. GRB220701A: VIRT Optical Upper Limit
  33. GRB 220701A: MITSuME Akeno optical upper limits
  34. GRB 220701A: COATLI Optical Upper Limit
  35. GRB 220701A: AbAO optical upper limit
  36. GRB 220701A: Keck/LRIS Optical Upper Limit
  37. GRB 220701A: LCO Optical Upper Limits
  38. GRB 220701A: BOOTES-5/JGT early optical upper limit
  39. GRB 220701A: Swift/UVOT Upper Limits
  40. GRB 220701A: Lowell Discovery Telescope Optical Observations
  41. GRB 200701A: KAIT Optical Upper Limit
  42. GRB 220627A, GROND observations
  43. GRB 220627A: Swift/UVOT Upper Limits
  44. GRB 220627A: VLT MUSE redshift
  45. GRB 220627A: MeerLICHT candidate optical afterglow
  46. GRB 220627A: MeerLICHT detection of two afterglow candidates
  47. GRB 220623A: GIT optical upper limits.
  48. GRB 220623A: T193-OHP optical upper limit
  49. GRB 220611A: X-ray afterglow Chandra sub-arcsecond localization
  50. GRB 220623A: AbAO optical upper limit
  51. GRB 220623A: NOT optical observations
  52. GRB 220623A: Swift/UVOT Upper Limits
  53. GRB 220623A: BOOTES-5/JGT optical afterglow detection
  54. GRB 220623A: iTelescope optical upper limit
  55. GRB 220618A: iTelescope T-19 upper limit
  56. GRB 220617A: TNG optical observations
  57. GRB 220611A optical counterpart
  58. GRB 220618A: BOOTES-5/JGT early optical upper limit
  59. GRB 220618A: Swift/UVOT Upper Limits
  60. GRB220611A: Gemini Optical Afterglow Confirmation
  61. GRB 220611A: Gemini Ks counterpart detection
  62. GRB 220611A: Swift/UVOT Upper Limits
  63. GRB 220606B: Gemini South Optical Observations
  64. GRB 220606B: Swift follow-up observations
  65. GRB 220527A: A BdHN I with a clear UPE phase
  66. GRB 220527A: MITSuME Akeno continued optical observation
  67. GRB 220527A: Lick 3m Optical Observations
  68. GRB 220527A: AST3-3 Yaoan Optical Observation
  69. GRB 220527A: REM optical/NIR observations
  70. GRB 220527A: NOT optical photometry and spectroscopic redshift
  71. GRB 220527A: MITSuME Akeno optical observation
  72. GRB 220521A: ATCA detection
  73. GRB 220521A: ALMA detection
  74. GRB 220521A: BOOTES-2/TELMA and CAHA 2.2m telescope optical upper limit
  75. GRB 220521A: ISON-Castelgrande observatory optical observations
  76. GRB 220521A: MITSuME Akeno optical upper limits
  77. GRB 220521A: Gemini Observations
  78. GRB 220521A: REM optical/NIR upper limits
  79. GRB 220521A: LCO Optical Detection
  80. GRB 220521A: Sintesz-Newton/CrAO optical upper limit
  81. GRB 220521A: RATIR Optical and NIR Observations
  82. GRB 220521A: Swift/UVOT Upper Limits
  83. GRB 220521A: SAO RAS optical observations
  84. GRB 220521A: NOT spectroscopic redshift
  85. GRB 220521A: NOT optical afterglow detection
  86. GRB 220514A: MITSuME Akeno optical observation
  87. GRB 220514A: GRANDMA Optical Afterglow Observations
  88. GRB 220514A: KAIT Optical Afterglow Confirmation
  89. GRB 220514A: MeerLICHT optical afterglow candidate
  90. GRB 220427A: MeerLICHT afterglow observations
  91. GRB 220511A: BOOTES-2/TELMA optical upper limit
  92. GRB 220506A: MITSuME Akeno optical upper limits
  93. GRB 220506A: GIT optical upper limit.
  94. GRB 220506A: BOOTES-5/JGT optical upper limit
  95. IceCube-220405B - ZTF19aavnpjv unrelated
  96. GRB 220430A: Nanshan/NEXT optical upper limit
  97. GRB 220430A: Nanshan/HMT optical upper limit
  98. GRB 220430A: GIT optical upper limits
  99. GRB 220427A: LCO Optical Observations
  100. GRB 220427A: GRANDMA Early Optical Afterglow Detection

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