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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"

16273 results found.

  1. IPN triangulation of GRB 201103B (consistent with ZTF20acozryr/AT2020yxz)
  2. ZTF20acozryr/AT2020yxz: Zwicky Transient Facility discovery of a fast optical transient with no associated GRB
  3. GRB 201104B: VLT/X-shooter redshift
  4. GRB 201104B: MASTER optical observation
  5. GRB 201029A: Swift/UVOT Upper Limits
  6. GRB 201029A: BOOTES-1 optical upper limit
  7. GRB 201029A: FRAM-ORM optical limit
  8. GRB 201027A: MITSuME Akeno optical upper limits
  9. GRB 201027A: Swift/UVOT Upper Limits
  10. GRB 201027A: 1.5m OSN optical upper limit
  11. GRB 201026A: Swift/UVOT Upper Limits
  12. GRB 201026A: FRAM-ORM optical detection limit
  13. GRB 201020A: 1.3m DFOT, optical upper limits
  14. GRB 201026A: NanShan/NEXT-0.6m optical upper limit
  15. GRB 201026A: NOT optical upper limits
  16. GRB 201024A: 1.3m DFOT optical observations
  17. GRB 201020B: 1.3m DFOT continued optical follow-up observations
  18. GRB 201024A: MITSuME Akeno optical upper limits
  19. GRB 201020B: HCT and GIT continued optical follow-up observations
  20. GRB 201020B: 1.3m DFOT optical observations
  21. GRB 201024A: VIRT optical observations
  22. GRB 201020B: follow-up observations at Konkoly
  23. GRB 201020B: continued Mondy optical observations
  24. GRB 200901A: FRAM-Auger optical limit
  25. GRB 201024A: BOOTES-2/TELMA early optical observation and 1.5m OSN follow-up
  26. GRB 201024A: Swift detection of a burst with an optical afterglow
  27. Swift GRB201024A: Global MASTER-Net OT detection
  28. IceCube-201021A: One candidate counterpart from the Zwicky Transient Facility
  29. IceCube-201021A: Optical counterpart of WISEA J172314.13+142101.5
  30. GRB 201020B: GROWTH-India Telescope optical observations
  31. GRB 201020B: Konkoly Obs. optical detection
  32. GRB 201020A: GROWTH-India Telescope late-time optical upper limit
  33. GRB 201020B: Swift-XRT afterglow detection
  34. GRB 201021C: VLT/X-shooter redshift
  35. GRB 201020A: VIRT optical observations
  36. GRB 201021C: MASTER optical synchronously observation
  37. GRB 201021C: Swift detection of a burst with an optical counterpart
  38. GRB 201020B: Mondy optical observations
  39. GRB 201015A: SAO RAS optical observations
  40. GRB 201020B: Nanshan/NEXT optical afterglow confirmation
  41. GRB 201020B: MASTER bright optical afterglow detection
  42. GRB 201020A: DOAO optical afterglow observations
  43. GRB 201020A: GROWTH-India Telescope optical observations
  44. GRB 201020A: CrAO/ZTSH optical observations
  45. GRB 201020A: Assy optical observations
  46. GRB 201020A: Nanshan/NEXT optical observations
  47. GRB 201014A: SAO RAS optical observations
  48. GRB 201020A: MITSuME Akeno optical observation
  49. GRB 201020A: Swift detection of a burst with an optical counterpart.
  50. GRB 201017A iTelescope observation
  51. GRB 201017A: SAO RAS optical observations
  52. GRB 201017A: GROWTH-India optical upper limit
  53. GRB 201014A: 3.6m DOT Optical Observations
  54. GRB 201015A: 6 GHz VLA radio afterglow candidate detection
  55. GRB 201013A: 3.6m DOT Optical Observations
  56. GRB 201014A: MMT afterglow detection
  57. GRB 201017A: MITSuME Akeno optical upper limits
  58. GRB 201015A: HCT optical photometric follow-up
  59. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection
  60. GRB 201015A: Xinglong-2.16m optical observations
  61. GRB 201015A: MMT afterglow imaging
  62. GRB 201015A NUTTelA-TAO / BSTI Early Measurements (Preliminary)
  63. GRB 201015A: Assy and Mondy optical observations
  64. GRB 201015A: classification as long GRB
  65. GRB 201015A: Swift/UVOT Detection
  66. GRB 201015A: redshift confirmation
  67. GRB 201015A: Swift-BAT refined analysis (a soft short pulse with a tail emission)
  68. GRB 201015A: CrAO/ZTSH optical observations
  69. GRB 201014A: Nanshan/NEXT optical observations
  70. GRB 201014A: Lowell Discovery Telescope afterglow imaging
  71. GRB201015A: Nanshan/NEXT early optical observations
  72. GRB 201015A: BOOTES-1 early optical afterglow detection
  73. GRB 201014A: Swift/UVOT Upper Limits
  74. GRB 201015A: GOTO confirmation of afterglow detection
  75. GRB 201015A: NOT optical afterglow confirmation
  76. Swift GRB201015.95: Global MASTER-Net OT detection
  77. GRB 201014A: BOOTES-1 and -2 early optical upper limits
  78. GRB 201014A (Swift trigger =1000255): CrAO/ZTSH optical afterglow discovery
  79. GRB 201013A: TSHAO and AbAO optical observations, afterglow confirmation
  80. GRB 201013A: FRAM-ORM possible afterglow candidate
  81. GRB 201013A: Swift/UVOT Upper Limits
  82. SGR 1830-0645: Swift/UVOT Upper Limits
  83. SGR 1830-0645 / GRB 201010A: 1.5m OSN optical upper limit
  84. SGR 1830-0645 / GRB 201010A: Kitab optical non-detection
  85. GRB 201006A: GROWTH-India Telescope optical upper limit
  86. GRB 201006A: MITSuME Akeno optical upper limits
  87. GRB 201006A: Swift/UVOT Upper Limits
  88. GRB 201001A: Swift/UVOT Upper Limits
  89. GRB 201001A: TSHAO optical upper limit
  90. GRB 201001A: Xinglong-2.16m optical upper limit
  91. GRB 201001A: MITSuME Akeno optical upper limits
  92. GRB 200925B: Swift/UVOT Detection
  93. GRB 200922A: Chilescope optical observations
  94. Swift GRB 200925B: Global MASTER-Net OT detection
  95. GRB 200922A: chance superposition between optical afterglow and archival star
  96. GRB 200917A: Swift/UVOT Upper Limits
  97. GRB 200922A: Swift detection of a burst with possible optical counterpart
  98. GRB 200919A: CrAO/ZTSh early optical upper limit
  99. GRB 200916B: MASTER optical observation
  100. IceCube-200916A: AbAO observations of optical candidates ZTF20acaapwk/AT2020tno, ZTF20acaapwo/AT2020tnp

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