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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16270 results found.

  1. GRB 210724A: Afterglow candidate from OSIRIS/GTC
  2. GRB 210725A: MITSuME Akeno optical upper limits
  3. GRB 210722A: continued Assy optical observations
  4. GRB 210722A: Nanshan/NEXT further optical observations
  5. GRB 210725A: KAIT Optical Upper Limit
  6. GRB210724A: MeerLICHT upper limits
  7. GRB 210722A: continued Assy optical observations
  8. GRB 210722A: D50 optical detection
  9. GRB 210722A: Kitab optical observations, light curve
  10. GRB 210722A: RATIR Optical Observations
  11. GRB 210722A: GIT optical detection and preliminary analysis
  12. GRB 210722A: Assy optical detection
  13. GRB 210722A: Nanshan/NEXT optical afterglow observations
  14. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  15. Konus-Wind detection of GRB 210714A
  16. Fermi trigger No 647942198: MASTER optical afterglow detection
  17. GRB 210704A: Zeiss-1000/SAO-RAS optical observations
  18. GRB 210712A: Swift/UVOT Upper Limits
  19. GRB 210712A: BOOTES-3/YA optical upper limit
  20. GRB 210704A: Lowell Discovery Telescope Optical Observations
  21. GRB 210704A: Continued Gemini-North NIR K-band Detections
  22. GRB 210704A: NOT optical observations and color change
  23. GRB210704A: Gemini near-infrared upper limits
  24. GRB 210704A: Assy optical afterglow upper limit
  25. GRB 210704A: OSIRIS/GTC Observations and Archival Detection of the Possible Host Galaxy
  26. GRB 210704A: Gemini-North Infrared Source Detection
  27. GRB 210704A: further TNG optical observations
  28. GRB 210708A: Swift/UVOT Upper Limits
  29. GRB 210702A: ATCA detection
  30. GRB 210702A: ALMA detection
  31. GRB 210704A: CAHA 2.2m telescope optical limit
  32. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  33. GRB 210706A: GIT optical upper limits
  34. GRB 210704A: OSIRIS/GTC spectroscopy
  35. GRB 210704A: CAHA 2.2m Afterglow Detection
  36. GRB 210704A: RATIR optical upper limits
  37. GRB 210704A: Swift/UVOT Upper Limits
  38. GRB 210619B: ALMA detection
  39. GRB 210704A: TNG detection of the optical afterglow candidate
  40. GRB 210704A: Assy optical afterglow candidate
  41. GRB 210704A: possible local hosts
  42. GRB 210702A: BOOTES-3/YA optical counterpart observations
  43. GRB 210702A: Chilescope optical observations
  44. GRB 210702A: iTelescope optical afterglow observations
  45. GRB 210702A: VLT/X-shooter redshift
  46. GRB210702A: MeerLICHT multi-colour photometry
  47. Swift GRB210702.80: Global MASTER-Net OT detection
  48. GRB 210702A: Swift detection of a burst with a bright optical counterpart
  49. IceCube-210629A: One Candidate Counterpart from the Zwicky Transient Facility
  50. GRB 210626A: CAHA 2.2m telescope optical limit
  51. GRB 210619B: Deep CAHA 2.2m detection and late-time light curve behavior
  52. GRB 210626A: Ondrejov D50 optical limit
  53. GRB 210626A: GIT optical upper limit
  54. GRB 210618A: 1.5m OSN optical upper limit
  55. GRB210619B: optical afterglow detection from Konkoly Observatory
  56. GRB 210610B: T-CAT optical observations
  57. GRB 210619B: Even further SAO RAS optical observations
  58. GRB 210619B: Mini-MegaTORTORA early optical observations
  59. GRB 210619B: Abbey Ridge Observatory optical afterglow observation
  60. GRB 210619B: Further SAO RAS optical observations
  61. GRB 210619B: possibility of lensed visible afterglow?
  62. GRB 210619B: AbAO optical observations
  63. GRB 210619B: NOT optical observations
  64. GRB 210619B: 1.5m OSN optical observation
  65. GRB 210619B: iTelescope optical afterglow observation
  66. GRB 210619B: SAO RAS optical observations
  67. GRB 210619B: SEDM Optical Observations
  68. GRB 210619B: REM optical/NIR afterglow detection
  69. GRB 210619B: GIT optical follow-up and confirmation of jet-break
  70. GRB 210619B: steepening of the decay observed at the D50
  71. GRB 210619B: Liverpool Telescope First Hour Observations
  72. GRB 210619B: Xinglong TNT optical observations
  73. GRB 210619B: KAIT Optical Detection
  74. GRB 210619B: Liverpool telescope imaging of a red afterglow
  75. GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
  76. GRB 210619B: iTelescope T18 detection
  77. GRB 210619B: Ondrejov D50 detection
  78. Swift GRB210619.99: Global MASTER-Net OT detection
  79. GRB 210619B: Swift detection of a bright burst and optical counterpart
  80. Swift GRB210619.99: Global MASTER-Net OT detection
  81. GRB 210618A: Swift/UVOT Upper Limits
  82. GRB 210618A: BOOTES-2/TELMA optical upper limit
  83. GRB 210618A: DDOTI upper limit for the optical afterglow
  84. GRB 210610B: Swift/UVOT Detection
  85. GRB 210610A: Swift/UVOT Detection
  86. GRB 210610B: CrAO/ZTSH continued optical observations and light curve
  87. GRB 210610B: AbAO optical observations
  88. GRB 210610B: REM optical/NIR observations of the afterglow
  89. Swift-BAT Trigger 1055000/GRB210612.54: MASTER optical source observation
  90. GRB 210610B: iTelescope optical afterglow observations
  91. GRB 210610B: Further SAO RAS optical observations
  92. GRB 210610A: SAO RAS optical observations
  93. GRB 210610B: optical observations from Burke-Gaffney Observatory and Abbey Ridge Observatory
  94. GRB 210610B: Continued KAIT Optical Detection
  95. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  96. GRB210610B: SARA-KP 0.9m Optical Afterglow Detection
  97. GRB 210610B: MITSuME Akeno optical observation
  98. GRB 210610B: VLA detection
  99. GRB 210610B: ALMA detection
  100. GRB 210610B: Liverpool Telescope optical photometry

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