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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"

16254 results found.

  1. GRB 210610B: NOT optical observations and tentative redshift
  2. GRB 210610B: iTelescope optical afterglow observations
  3. GRB210610B: MeerLICHT multi-colour photometry
  4. GRB 210610B: CrAO/ZTSh optical afterglow photometry
  5. GRB 210610B: BOOTES-2/TELMA optical observation
  6. GRB 210610B: CrAO/ZTSh optical observations
  7. GRB 210610B: GIT optical detection
  8. Swift GRB210610.83: Global MASTER-Net OT detection
  9. GRB 210610B: Swift detection of a burst with bright optical afterglow
  10. GRB 210610A: MITSuME Ishigaki optical observation
  11. GRB210610A: MeerLICHT multi-colour photometry
  12. Swift GRB 210610A: MASTER optical counterpart observation
  13. GRB 210610A: Xinglong-2.16m redshift
  14. GRB 210610A: GIT optical detection
  15. GRB 210610A: Xinglong-2.16m optical afterglow observations
  16. GRB 210610A: MITSuME Akeno optical observation
  17. GRB 210610A: Swift detection of a burst with an optical counterpart
  18. GRB 210606A: 1.5m OSN optical upper limit
  19. GRB 210528B: MITSuME Akeno optical upper limits
  20. GRB 210527A: Swift/UVOT Observations
  21. GRB 210527A: GIT optical upper limit
  22. GRB 210527A: MITSuME Akeno optical upper limits
  23. GRB 210527A: RATIR Optical and NIR Observations
  24. GRB 210306A: LBT observations of the likely host galaxy
  25. ZTF21aayokph (AT2021lfa): LBT optical observations
  26. ZTF21aayokph (AT2021lfa): continued Assy optical observations
  27. GRB 210517A: KCT optical upper limit
  28. GRB 210517A: Swift/UVOT Upper Limits
  29. GRB 210515C: Swift/UVOT Upper Limits
  30. GRB 210517A: VLT/X-shooter optical afterglow and redshift
  31. GRB 210515C: LCO Optical Upper Limit
  32. GRB 210504A: LCO Optical Afterglow Detection
  33. GRB 210514A: Swift/UVOT Upper Limits
  34. GRB 210514A: Swift-BAT refined analysis
  35. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  36. Short GRB 210323A: likely host galaxy detection
  37. GRB 210509A: RATIR Optical and NIR Upper Limits
  38. GRB 210509A: Swift/UVOT Upper Limits
  39. GRB 210509A: BOOTES-4/MET optical upper limit
  40. ZTF21aayokph (AT2021lfa): continued Mondy optical observations
  41. ZTF21aayokph (AT2021lfa): MASTER OT detection 3h befor ZTF
  42. GRB 210506A: Nanshan/NEXT optical upper limit
  43. ZTF21aayokph (AT2021lfa): Mondy and Koshka observatory optical observations
  44. ZTF21aayokph (AT2021lfa): Assy optical observations
  45. ZTF21aayokph (AT2021lfa): Nanshan/NEXT optical upper limit
  46. GRB 210504A: Lowell Discovery Telescope optical observations
  47. GRB 210504A: VLT X-shooter redshift
  48. GRB 210504A: NOT optical afterglow detection
  49. GRB 210504A: MITSuME Akeno optical upper limits
  50. GRB 210504A: AST3-3 YaoAn Optical Upper Limit
  51. GRB 210504A: BOOTES-4/MET optical upper limit
  52. Swift Detection of MAXI J1803-298 including an optical counterpart
  53. GRB 210430A: BOOTES-1 optical limit
  54. GRB 210424B: MITSuME Akeno optical upper limits
  55. GRB 210420B: Assy optical observations
  56. GRB 210420B: follow-up photometry of optical afterglow at INASAN/Simeiz
  57. GRB 210420B: Zeiss-1000 of Koshka optical observations
  58. GRB 210420B: continued Tautenburg observations
  59. GRB 210421A: Swift/UVOT Upper Limits
  60. GRB 210420B: follow-up photometry of the optical afterglow at Konkoly
  61. GRB 210421A: MITSuME Akeno optical upper limits
  62. GRB 210419C: Swift/UVOT Upper Limits
  63. GRB 210420B: Ondrejov D50 optical afterglow detection
  64. GRB 210420B: RATIR Optical and NIR Observations
  65. GRB 210420B: Swift/UVOT Detection
  66. GRB 210420B: KAIT Optical Observations
  67. GRB 210413B: MITSuME Okayama optical upper limits
  68. GRB 210419C: MITSuME Akeno optical upper limits
  69. GRB 210420B: Multiband photometry from NOT
  70. GRB 210420B: Montarrenti Observatory optical afterglow detection
  71. GRB 210420B: AST3-3 YaoAn Optical Observation
  72. GRB 210420B: BOOTES-4/MET optical afterglow detection
  73. GRB 210420B: Optical observations
  74. GRB 210420B: MASTER optical counterpart detection
  75. GRB 210419C: RATIR Optical and NIR Upper Limits
  76. GRB 210419C: Montarrenti Observatory Upper Limit
  77. GRB 210419A: Swift/UVOT Upper Limits
  78. GRB 210419C: KAIT Optical Upper Limit
  79. GRB 210419A: LCO Optical Upper Limit
  80. GRB 210413B: LOAO optical upper limit
  81. IceCubeCascade-210416a: Kanata Optical Imaging of 3C 279
  82. GRB 210411C: Chilescope optical observations
  83. GRB 210411C: ePESSTO+ NTT optical observations
  84. GRB 210411C: VLT/X-shooter redshift
  85. GRB 210410A: MITSuME Akeno optical upper limits
  86. GRB 210411C: BOOTES-4/MET optical upper limit
  87. GRB 210411C: LCO Optical Afterglow Candidate
  88. GRB 210406A: 10.4m GTC follow-up observation
  89. GRB 210411C: Swift detection of a burst with an optical counterpart
  90. GRB 210410A: Swift/UVOT Upper Limits
  91. GRB210410A: Joint inspection of RATIR and D50 data
  92. GRB 210406A: Swift-XRT observations
  93. GRB 210410A: RATIR Optical and NIR Observations
  94. GRB210410A: Candidate optical afterglow by Ondrejov D50
  95. GRB 210406A: Mondy optical afterglow candidate
  96. GRB 210406A: Mondy optical upper limit
  97. GRB 210406A: Konkoly Obs. optical upper limit
  98. GRB 210406A: BOOTES-4/MET optical upper limit
  99. GRB 210402A: MASTER prompt and follow up optical observation
  100. GRB 210402A: Swift/UVOT Upper Limits

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