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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 221028A: GRANDMA observations
  2. GRB 221027B: GRANDMA observations
  3. GRB 221028A: 1.3m DFOT Optical upper limit
  4. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  5. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  6. GRB 221028A: AKO Optical Upper Limit
  7. GRB 221028A: CrAO/ZTSh optical upper limit
  8. GRB 221028A: HCT optical upper limit
  9. GRB 221028A: MITSuME Okayama optical upper limits
  10. GRB 221028A: LCOGT Optical Upper Limits
  11. GRB 221028A: BOOTES-4/MET optical upper limit
  12. GRB 221028A: GIT optical upper limit
  13. GRB 221027B: Swift/UVOT Upper Limits
  14. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  15. GRB 221027B: BOOTES-1 optical upper limit
  16. GRB 221024A: Mondy optical observations
  17. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  18. GRB 221009A: spectroscopic confirmation of SN in LBT spectra
  19. GRB 221024A: GIT confirmation of the optical afterglow
  20. GRB 221009A: James Webb Space Telescope Observations
  21. GRB 221009A: optical observations, SN photometric evidence
  22. GRB 221009A: 1.3m DFOT Optical Observations
  23. GRB221009A: LBT optical imaging
  24. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  25. GRB 221009A: BOAO NIR detections
  26. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  27. GRB 221009A: Medicina Radio Telescope observations
  28. GRB 221009A: A type I BdHN of exceptional energetics
  29. GRB 221016A: z-band upper limit, possible afterglow brightening
  30. GRB 221016A: LCOGT Optical Afterglow Detection
  31. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  32. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  33. GRB 221009A: VLT spectroscopic detection of the host galaxy
  34. GRB 221009A: ATCA detection
  35. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  36. GRB 221009A: Pan-STARRS optical photometry
  37. GRB 221009A: VLA detection
  38. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  39. GRB 221009A: OHP optical observations
  40. GRB221009A: RTT-150 optical observations
  41. GRB 221009A: Gemini-South Infrared Afterglow Detection
  42. GRB221009A: Gemini-South Optical Afterglow Detection
  43. GRB221009A: RTT-150 optical observations
  44. GRB 221009A: MeerKAT detection
  45. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  46. GRB 221009A: MITSuME Okayama optical observation
  47. GRB 221009A: Sayan observatory 1.6-m telescope observations
  48. GRB 221009A: GMG observation
  49. GRB221009A: optical afterglow measurements from Konkoly Observatory
  50. GRB 221009A: LCOGT Optical Afterglow Detection
  51. GRB 221009A: 10.4m GTC spectroscopic redshift confirmation
  52. GRB 221009A: Sintez-Newton/CrAO optical observations
  53. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  54. GRB 221009A: BlackGEM optical observations
  55. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  56. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  57. GRB 221009A: Lulin SLT-40cm optical observations
  58. Swift J1913.1+1946: New Photometry
  59. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  60. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  61. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  62. ​GRB 221009A: Multi-color detection of the optical
  63. GRB 221009A: Fermi-LAT refined analysis
  64. GRB 221009: Swift/UVOT Detection
  65. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  66. GRB 221009A: REM optical and NIR detection of the afterglow
  67. Swift J1913.1+1946: Early Optical Photometry
  68. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  69. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  70. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  71. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  72. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  73. Swift J1913.1+1946: Optical photometry
  74. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  75. Swift GRB221009.59: Global MASTER-Net OT detection
  76. Swift J1913.1+1946 a new bright hard X-ray and optical transient
  77. GRB 220930A: MITSuME Akeno optical upper limits
  78. GRB 220921A: ATCA detection of radio counterpart
  79. GRB 220930A: AbAO Optical Upper Limit
  80. GRB 220930A: LCOGT Optical Upper Limits
  81. GRB 220930A: Swift/UVOT Upper Limits
  82. GRB 220930A: BOOTES-5/JGT early optical upper limit
  83. GRB 220921A: LCOGT Optical Observations
  84. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  85. GRB 220921A: ALMA detection
  86. IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
  87. GRB 220921A: Swift-XRT Observations
  88. GRB 220831A: DECam optical counterpart follow-up
  89. GRB 220831A: Gemini-South Infrared Observations
  90. GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
  91. GRB 220907A: Nanshan/NEXT optical upper limits
  92. GRB 220907A: Swift/UVOT Upper Limits
  93. GRB 220831A: Swift-UVOT Upper Limits
  94. GRB 220831A: DECam detection of a possible optical counterpart
  95. IceCube-220822A: Classification of AT2022saw as a Type Ia supernova
  96. GRB 220826A: Lesedi optical afterglow detection
  97. GRB 220826A: iTelescope optical afterglow observations
  98. GRB 220826A: Swift detection of a burst with an optical counterpart
  99. GRB 220813A: VLT optical observations and possible host galaxy
  100. GRB 220810A: Further Swift-XRT observations

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