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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"

36192 results found.

  1. GRB 210722A: Swift-BAT refined analysis
  2. GRB 210722A: Kitab optical observations, light curve
  3. GRB 210722A: Redshift from OSIRIS/GTC
  4. GRB 210723A: Prompt enhanced Swift-XRT position
  5. GRB 210723A: Swift detection of a burst
  6. GRB 210722A: RATIR Optical Observations
  7. GRB 210722A: Swift-XRT refined Analysis
  8. GRB 210722A: Swift/UVOT Detection
  9. GRB 210722A: GIT optical detection and preliminary analysis
  10. Swift GRB 210722A: Global MASTER-Net observations report
  11. GRB 210702A: ALMA detection of mm-band rebrightening
  12. GRB 210722A: Assy optical detection
  13. GRB 210702A: ATCA detection of radio rebrightening
  14. GRB 210722A: Nanshan/NEXT optical afterglow observations
  15. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  16. GRB 210719A: GECAM detection
  17. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  18. Konus-Wind detection of GRB 210714A
  19. GRB 210704A: Zeiss-1000/SAO-RAS optical observations
  20. GRB 210715B: DDOTI Upper Limits on the Afterglow
  21. GRB 210712A: Swift-BAT refined analysis
  22. GRB 210712A: Swift-XRT refined Analysis
  23. GRB 210712A: Swift/UVOT Upper Limits
  24. GRB 210712A: BOOTES-3/YA optical upper limit
  25. GRB 210712A: Enhanced Swift-XRT position
  26. GRB 210704A: classification as long GRB and redshift estimating
  27. GRB 210704A: Lowell Discovery Telescope Optical Observations
  28. GRB 210712A: Swift detection of a burst
  29. GRB 210709A: AstroSat CZTI detection
  30. GRB 210704A: Continued Gemini-North NIR K-band Detections
  31. GRB 210704A: INTEGRAL observations
  32. GRB 210704A: NOT optical observations and color change
  33. GRB210704A: Gemini near-infrared upper limits
  34. GRB 210704A: Assy optical afterglow upper limit
  35. GRB 210704A: OSIRIS/GTC Observations and Archival Detection of the Possible Host Galaxy
  36. GRB 210704A: Gemini-North Infrared Source Detection
  37. GRB 210704A: further TNG optical observations
  38. GRB 210706A: Swift/XRT afterglow confirmation
  39. GRB 210708B: Swift-BAT refined analysis
  40. Fermi GRB 210709A: Global MASTER-Net observations report
  41. GRB 210709A: Fermi GBM Final Real-time Localization
  42. Swift GRB 210708B: Global MASTER-Net observations report
  43. GRB 210708A: Swift/UVOT Upper Limits
  44. GRB 210702A: ATCA detection
  45. GRB 210702A: ALMA detection
  46. GRB 210708A: Swift-BAT refined analysis
  47. Fermi GBM Sub-Threshold Detection of GRB 210708A
  48. Fermi GBM Sub-Threshold Detection of GRB 210707A
  49. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  50. GRB 210708B: Swift detection of a possible burst
  51. GRB 210708A: Swift-XRT refined Analysis
  52. GRB 210707A: A long GRB detected by INTEGRAL
  53. GRB 210708A: Swift detection of a burst
  54. GRB 210704A: CAHA 2.2m telescope optical limit
  55. GRB 210706A: Fermi GBM observation
  56. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  57. Konus-Wind detection of GRB 210706A
  58. GRB 210706A: GIT optical upper limits
  59. GRB 210704A: OAJ T80 multi-color detections
  60. GRB 210706A: Swift-XRT afterglow detection
  61. GRB 210706A: Swift ToO observations
  62. GRB 210706A: Swift/BAT-GUANO detection and arcminute localization
  63. GRB 210704A: OSIRIS/GTC spectroscopy
  64. GRB 210704A: CAHA 2.2m Afterglow Detection
  65. GRB 210704A: RATIR optical upper limits
  66. GRB 210704A: Swift/UVOT Upper Limits
  67. Konus-Wind detection of GRB 210704A
  68. GRB 210704B: AstroSat CZTI detection
  69. GRB 210619B: ALMA detection
  70. GRB 210704A: TNG detection of the optical afterglow candidate
  71. GRB 210704A: Assy optical afterglow candidate
  72. GRB 210704A: DDOTI upper limit
  73. GRB 210704B: Fermi GBM detection
  74. GRB 210704A: possible local hosts
  75. GRB 210704A: Fermi GBM detection
  76. GRB 210704A: Swift-XRT afterglow detection
  77. GRB 210704A: AstroSat CZTI detection
  78. IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  79. IceCube-210510A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  80. GRB 210704A: Fermi-LAT detection
  81. GRB 210704A: Swift ToO observations
  82. GRB 210705A: AGILE/MCAL detection of a burst
  83. GRB 210704A: AGILE/MCAL detection
  84. GRB 210704A: BALROG localization (Fermi Trigger 647120009 / GRB 210704815)
  85. GRB 210702A, Swift-BAT refined analysis
  86. GRB 210702A: BOOTES-3/YA optical counterpart observations
  87. Konus-Wind detection of GRB 210702A
  88. GRB 210702A: Chilescope optical observations
  89. GRB 210702A: iTelescope optical afterglow observations
  90. GRB 210702A: AGILE detection
  91. GRB 210702A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 210619B: JCMT SCUBA-2 sub-mm observations
  93. GRB 210610B: JCMT SCUBA-2 sub-mm observations
  94. GRB 210610A: JCMT SCUBA-2 sub-mm observations
  95. GRB 210702A: Swift-XRT refined Analysis
  96. GRB 210702A: VLT/X-shooter redshift
  97. GRB 210702A: preliminary Swift/UVOT photometry
  98. GRB 210702A: Swift/UVOT redshift
  99. Swift GRB 210702A: Global MASTER-Net observations report
  100. GRB 210702A: Swift detection of a burst with a bright optical counterpart

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