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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"

16156 results found.

  1. GRB 210306A: continued Mondy optical observations
  2. GRB 210308A: Mondy and AbAO optical observations
  3. GRB 210307A: Swift/UVOT Upper Limits
  4. GRB 210308A: Nanshan/NEXT optical upper limits
  5. GRB 210308A: MITSuME Okayama optical upper limits
  6. GRB 210306A: continued Mondy optical observations
  7. GRB 210308A: Swift detection of a burst with an optical counterpart
  8. GRB 210306A: 1.3m DFOT observations
  9. GRB 210306A: Mondy optical observations
  10. GRB 210305A: Swift/UVOT Upper Limits
  11. GRB 210307A: LCO Optical Upper Limits
  12. GRB 210306A: MITSuME Akeno optical observation
  13. GRB 210306A: NEXT optical observations
  14. GRB 210306A: iTelescope T24 optical observations
  15. GRB 210306A: LCO Optical Afterglow Detection
  16. GRB 210306A: iTelescope optical afterglow observations
  17. GRB 210306A: Swift detection of a burst with a bright optical counterpart
  18. GRB 210217A: 3.6m DOT optical observations
  19. GRB 210226A: Swift/UVOT Upper Limits
  20. Integral GRB210227.19: MASTER OT retraction
  21. Integral GRB210227.19: Global MASTER-Net OT detection
  22. GRB 210217A: Mondy optical observations
  23. GRB 210226A: KAIT Optical Upper Limit
  24. GRB 210226A: Burke-Gaffney Observatory optical upper limit
  25. GRB 210226A: Ondrejov BART/SBT optical limit
  26. GRB 210222B: 1.3m DFOT Optical upper limit
  27. GRB 210222B: REM observations of the optical/NIR afterglow
  28. GRB 210222B: MITSuME Akeno optical upper limits
  29. GRB 210222B: Zeiss-1000 of Koshka observatory, optical observations
  30. GRB 210222B: VIRT optical detection
  31. GRB 210222B: Swift/UVOT Detection
  32. GRB 210222B: KAIT Optical Upper Limit
  33. GRB 210218A: Swift/UVOT observations
  34. GRB 210222B: MASTER OT observation
  35. GRB 210222B: NEXT early optical afterglow observations
  36. GRB 210222B: Liverpool Telescope optical detection
  37. GRB 210222B: GOTO confirmation of afterglow detection
  38. GRB210222B: LCO Optical Afterglow Detection
  39. GRB210222B: BOOTES-1 optical afterglow detection
  40. GRB 210222B: Swift detection of a burst with an optical counterpart
  41. GRB 210217A: 1.3m DFOT optical detection
  42. GRB 210217A: Liverpool Telescope First Hour Observations
  43. GRB 210217A: KAIT Optical Observations
  44. GRB 210218A: MITSuME Akeno optical upper limits
  45. GRB 210218A： GWAC-F60A optical upper limit
  46. GRB 210218A: NEXT optical upper limit
  47. ZTF21aakruew/AT2021cwd: GROND observations
  48. GRB 210212A: REM early-time optical/NIR upper limits
  49. GRB 210205A: observations with the 3.6m DOT, a potential dark burst?
  50. GRB 210217A: NEXT early optical afterglow observations
  51. GRB 210212A: Mondy optical observations
  52. GRB 210217A: Swift detection of a burst with an optical counterpart
  53. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Assy and Mondy optical observations
  54. IceCube-210210A: Two Additional Optical Candidate Counterparts Found by DECam
  55. GRB 210208A: 1.3m DFOT Optical upper limit
  56. GRB 210211A: ePESSTO+ NTT optical observations
  57. GRB 210212B (TF21aakruew/AT2021cwd): Assy optical observations
  58. IPN triangulation of GRB 210212B (consistent with ZTF21aakruew/AT2021cwd)
  59. GRB 210212A: 1.3m DFOT Optical upper limit
  60. ZTF21aakruew/AT2021cwd: ZTF and LT discovery of a hostless, red, and rapidly fading optical transient
  61. GRB 210212A: Gemini South optical observations
  62. GRB 210210A: CAHA 2nd epoch and jet break confirmation
  63. IceCube-210210A: Four Candidate Optical Counterparts from DECam Observations
  64. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued CrAO and AbAO optical observations
  65. GRB 210212A: Possible host galaxy counterpart with the NOT
  66. GRB 210212A: MITSuME Akeno optical upper limits
  67. GRB 210212A: BOOTES-4/MET optical upper limit
  68. GRB 210212A: Swift/UVOT Upper Limits
  69. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  70. GRB 210210A : 1.3m DFOT optical observations
  71. GRB 210210A as a BdHN II
  72. Swift-XRT observations of IceCube-210210A
  73. GRB 210211A: MASTER optical observation of REM OT
  74. GRB 210210A: CAHA detection and likely jet break
  75. GRB 210211A: REM optical/NIR afterglow detection
  76. GRB 210210A: FRAM-ORM afterglow detection
  77. GRB 210209A: BOOTES-4/MET optical upper limit
  78. GRB 210210A: LCO Optical Afterglow Detection
  79. GRB 210209A: MITSuME Akeno optical upper limits
  80. GRB 210209A: Swift/UVOT Upper Limits
  81. GRB 210208A: GIT optical upper limit
  82. GRB 210210A: MASTER afterglow observation
  83. ZTF21aahifke/AT2021clk: ZTF discovery of an optical fast transient (possible afterglow)
  84. GRB 210210A: Swift detection of a burst with an optical counterpart
  85. GRB 210207B: Continued LCO Observations
  86. GRB 210208A: BOOTES-2/TELMA optical upper limit
  87. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Mondy optical observations
  88. GRB 210207B: LCO Optical Afterglow Detection
  89. GRB 210207B: KAIT Optical Observations
  90. GRB 210207B: AbAO optical upper limit
  91. GRB 210207B: optical detection with 3.6m Devasthal Optical Telescope
  92. GRB 210207B: Swift detection of a burst with a bright optical counterpart
  93. GRB 210204A (ZTF21aagwbjr/AT2021buv): Mondy and AbAO optical observations
  94. Konus-Wind detection of GRB 210204A / ZTF21aagwbjr
  95. GRB 210204A: Optical Observations from HCT
  96. VLT/X-shooter redshift of 1.466 for ZTF21aagwbjr/AT2021buv, strengthening its association with GRB 210204A
  97. IPN triangulation of GRB 210204A
  98. GRB 210205A: MITSuME Ishigaki optical observation
  99. ZTF21aagwbjr/AT2021buv: ZTF discovery of a fast optical transient likely associated with GRB 210104A
  100. GRB 210205A: Swift/UVOT Upper Limits

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