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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"

16180 results found.

  1. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  2. GRB 221009A: Pan-STARRS optical photometry
  3. GRB 221009A: VLA detection
  4. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  5. GRB 221009A: OHP optical observations
  6. GRB221009A: RTT-150 optical observations
  7. GRB 221009A: Gemini-South Infrared Afterglow Detection
  8. GRB221009A: Gemini-South Optical Afterglow Detection
  9. GRB221009A: RTT-150 optical observations
  10. GRB 221009A: MeerKAT detection
  11. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  12. GRB 221009A: MITSuME Okayama optical observation
  13. GRB 221009A: Sayan observatory 1.6-m telescope observations
  14. GRB 221009A: GMG observation
  15. GRB221009A: optical afterglow measurements from Konkoly Observatory
  16. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  17. GRB 221009A: LCOGT Optical Afterglow Detection
  18. GRB 221009A: 10.4m GTC spectroscopic redshift confirmation
  19. GRB 221009A: Sintez-Newton/CrAO optical observations
  20. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  21. GRB 221009A: BlackGEM optical observations
  22. GRB 221009A: Continued Swift/XRT observations
  23. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  24. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  25. GRB 221009A: Lulin SLT-40cm optical observations
  26. Swift J1913.1+1946: New Photometry
  27. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  28. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  29. ​GRB 221009A: Multi-color detection of the optical
  30. GRB 221009A: Fermi-LAT refined analysis
  31. GRB 221009: Swift/UVOT Detection
  32. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  33. GRB 221009A: REM optical and NIR detection of the afterglow
  34. Swift J1913.1+1946: Early Optical Photometry
  35. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  36. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  37. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  38. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  39. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  40. Swift J1913.1+1946: Optical photometry
  41. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  42. Swift GRB221009.59: Global MASTER-Net OT detection
  43. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  44. GRB 220930A: MITSuME Akeno optical upper limits
  45. GRB 220921A: ATCA detection of radio counterpart
  46. GRB 220930A: AbAO Optical Upper Limit
  47. GRB 220930A: LCOGT Optical Upper Limits
  48. GRB 220930A: Swift/UVOT Upper Limits
  49. GRB 220930A: BOOTES-5/JGT early optical upper limit
  50. GRB 220921A: LCOGT Optical Observations
  51. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  52. GRB 220921A: ALMA detection
  53. GRB 220921A: DDOTI Detection of the Afterglow
  54. IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
  55. GRB 220921A: MeerLICHT afterglow observations
  56. GRB 220921A: Swift-XRT Observations
  57. GRB 220831A: DECam optical counterpart follow-up
  58. GRB 220831A: Gemini-South Infrared Observations
  59. GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
  60. GRB 220907A: Nanshan/NEXT optical upper limits
  61. GRB 220907A: Swift/UVOT Upper Limits
  62. GRB 220831A: Swift-UVOT Upper Limits
  63. GRB 220831A: DECam detection of a possible optical counterpart
  64. IceCube-220822A: Classification of AT2022saw as a Type Ia supernova
  65. GRB 220826A: Lesedi optical afterglow detection
  66. GRB 220826A: iTelescope optical afterglow observations
  67. GRB 220826A: Swift detection of a burst with an optical counterpart
  68. GRB 220813A: VLT optical observations and possible host galaxy
  69. GRB 220810A: Further Swift-XRT observations
  70. GRB 220813A: Swift detection of a burst with an optical counterpart
  71. GRB 220810A: Swift-XRT observations
  72. GRB 220810A: MeerLICHT detection of two afterglow candidates
  73. GRB 220730A: Swift/UVOT Upper Limits
  74. GRB 220715B: VIRT Optical Upper Limit
  75. GRB 220715B: Swift/UVOT Upper Limits
  76. GRB 220715B: BOOTES-network optical upper limits
  77. GRB 220714B: LCO Optical Observations
  78. GRB 220710A: Swift/UVOT Upper Limits
  79. GRB 220711B, GROND observations
  80. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  81. GRB 220711B: GIT optical upper limits
  82. GRB 220712B: NOT optical afterglow confirmation
  83. GRB 220711B: Swift/UVOT Upper Limits
  84. GRB 220711B: NOT optical observations
  85. GRB 220711B: LCO Optical Upper Limits
  86. GRB 220708B: GIT optical upper limits
  87. GRB 220708B: T193-OHP optical upper limit
  88. IceCube-220624A: Classification of AT2022nit as a type Ia supernova and AT2021bei as an AGN
  89. GRB 220708B: Nanshan/NEXT optical upper limits
  90. GRB 220708A: Swift/UVOT Upper Limits
  91. GRB 220706A: Swift/UVOT Upper Limits
  92. GRB 220708A: BOOTES-5/JGT early optical upper limit
  93. GRB 220706A: LCO Optical Upper Limits
  94. GRB 220627A: ATCA detection of radio counterpart
  95. GRB 220706A, GROND observations
  96. GRB 220706A: Optical observations from NOT
  97. GRB 220706A: Nanshan/NEXT optical upper limits
  98. GRB 220706A: Zadko observatory - Gingin optical observations
  99. GRB220408A: VIRT Optical Upper Limit
  100. GRB220412A: VIRT Optical Upper Limit

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