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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"

16152 results found.

  1. GRB 210824A: Nanshan/NEXT optical upper limit
  2. GRB 210822A: Abbey Ridge Observatory optical afterglow observation
  3. GRB 210822A: NOT photometry and spectroscopy
  4. GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  5. GRB 210822A: Nanshan/NEXT optical observations
  6. GRB 210822A: RATIR Optical Detections
  7. GRB 210822A: KAIT Optical Afterglow Confirmation
  8. GRB 210822A: Swift detection of a burst with an optical afterglow
  9. GRB 210820A: LT optical upper limit
  10. GRB 210820A: LCO Optical Upper Limit
  11. GRB 210820A: RATIR Optical Detections
  12. GRB 210820A: NOT optical upper limit
  13. GRB 210820A: Nanshan/NEXT optical upper limit
  14. GRB 210820A: Swift detection of a burst with an optical counterpart
  15. GRB 210818A: Swift detection of a burst with an optical counterpart
  16. Fermi-LAT Gamma-ray Observations of IceCube-210811A
  17. GRB 210807A: continued Assy, AbAO and Mondy observations
  18. GRB 210807A: Tautenburg observations
  19. GRB 210807C: Swift/UVOT Upper Limits
  20. GRB 210807A: correction to the GCN Circ. #30614 Assy optical observations
  21. GRB 210610B: Assy optical observations
  22. GRB 210807A: BOOTES-5/JGT optical afterglow detection
  23. GRB 210807A: Swift detection of a burst with an optical counterpart
  24. GRB 210802A: MITSuME Okayama optical upper limits
  25. GRB 210802A: BOOTES-2/TELMA optical upper limit
  26. GRB 210731A: continued GROND observations
  27. GRB 210731A: KAIT Optical Detection
  28. GRB 210731A: MASTER optical afterglow detection
  29. GRB 210731A: GROND observations
  30. GRB 210731A: Swift/UVOT Detection of an optical afterglow
  31. GRB 210731A: MeerLICHT optical afterglow detection
  32. Fermi-LAT Gamma-ray Observations of IceCube-210730A
  33. GRB 210730A: Campo Imperatore optical observations
  34. GRB 210730A: BOOTES-5/JGT and 2.2m CAHA telescopes optical limit
  35. GRB 210730A: TNG optical observations
  36. GRB 210730A: Swift/UVOT Upper Limits
  37. GRB 210724A: Corrected Swift-XRT enhanced position
  38. GRB 210702A: MeerKAT radio detection
  39. GRB 210726A: RATIR Optical Upper Limits and Candidate Host Galaxy
  40. GRB 210725A: AbAO optical upper limit
  41. GRB 210724A: Swift/UVOT Upper Limits
  42. GRB 210723A: Swift/UVOT Upper Limits
  43. GRB 210725A: Swift/UVOT Upper Limits
  44. GRB 210725B: Swift/UVOT Upper Limits
  45. GRB 210726A: CAHA 2.2m telescope optical limit
  46. GRB 210724A: Zeiss-1000 of Koshka observatory, optical upper limit
  47. GRB 210724A: Afterglow candidate from OSIRIS/GTC
  48. GRB 210725A: MITSuME Akeno optical upper limits
  49. GRB 210722A: continued Assy optical observations
  50. GRB 210722A: Nanshan/NEXT further optical observations
  51. GRB 210725A: KAIT Optical Upper Limit
  52. GRB210724A: MeerLICHT upper limits
  53. GRB 210722A: continued Assy optical observations
  54. GRB 210722A: D50 optical detection
  55. GRB 210722A: Kitab optical observations, light curve
  56. GRB 210722A: RATIR Optical Observations
  57. GRB 210722A: GIT optical detection and preliminary analysis
  58. GRB 210722A: Assy optical detection
  59. GRB 210722A: Nanshan/NEXT optical afterglow observations
  60. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  61. Fermi-LAT Gamma-ray Observations of IceCube-210717A
  62. Konus-Wind detection of GRB 210714A
  63. Fermi trigger No 647942198: MASTER optical afterglow detection
  64. GRB 210704A: Zeiss-1000/SAO-RAS optical observations
  65. GRB 210712A: Swift/UVOT Upper Limits
  66. GRB 210712A: BOOTES-3/YA optical upper limit
  67. GRB 210704A: Lowell Discovery Telescope Optical Observations
  68. GRB 210704A: Continued Gemini-North NIR K-band Detections
  69. GRB 210704A: NOT optical observations and color change
  70. GRB210704A: Gemini near-infrared upper limits
  71. GRB 210704A: Assy optical afterglow upper limit
  72. GRB 210704A: OSIRIS/GTC Observations and Archival Detection of the Possible Host Galaxy
  73. GRB 210704A: Gemini-North Infrared Source Detection
  74. GRB 210704A: further TNG optical observations
  75. GRB 210708A: Swift/UVOT Upper Limits
  76. GRB 210702A: ATCA detection
  77. GRB 210702A: ALMA detection
  78. GRB 210704A: CAHA 2.2m telescope optical limit
  79. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  80. GRB 210706A: GIT optical upper limits
  81. GRB 210704A: OSIRIS/GTC spectroscopy
  82. GRB 210704A: CAHA 2.2m Afterglow Detection
  83. GRB 210704A: RATIR optical upper limits
  84. GRB 210704A: Swift/UVOT Upper Limits
  85. GRB 210619B: ALMA detection
  86. GRB 210704A: TNG detection of the optical afterglow candidate
  87. GRB 210704A: Assy optical afterglow candidate
  88. GRB 210704A: possible local hosts
  89. GRB 210702A: BOOTES-3/YA optical counterpart observations
  90. GRB 210702A: Chilescope optical observations
  91. GRB 210702A: iTelescope optical afterglow observations
  92. GRB 210702A: VLT/X-shooter redshift
  93. GRB210702A: MeerLICHT multi-colour photometry
  94. Swift GRB210702.80: Global MASTER-Net OT detection
  95. GRB 210702A: Swift detection of a burst with a bright optical counterpart
  96. IceCube-210629A: One Candidate Counterpart from the Zwicky Transient Facility
  97. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  98. GRB 210619B: Sayan observatory 1.6-m telescope observations
  99. GRB 210626A: CAHA 2.2m telescope optical limit
  100. GRB 210619B: Deep CAHA 2.2m detection and late-time light curve behavior

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