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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"

39466 results found.

  1. GRB 210723A: Swift-BAT refined analysis
  2. GRB 210722A: continued Assy optical observations
  3. GRB 210723A: Swift-XRT refined Analysis
  4. GRB 210722A: D50 optical detection
  5. Swift GRB 210723A: Global MASTER-Net observations report
  6. GRB 210722A: Fermi GBM observation
  7. GRB 210722A: Swift-BAT refined analysis
  8. GRB 210722A: Kitab optical observations, light curve
  9. GRB 210722A: Redshift from OSIRIS/GTC
  10. GRB 210723A: Prompt enhanced Swift-XRT position
  11. GRB 210723A: Swift detection of a burst
  12. GRB 210722A: RATIR Optical Observations
  13. GRB 210722A: Swift-XRT refined Analysis
  14. GRB 210722A: Swift/UVOT Detection
  15. GRB 210722A: GIT optical detection and preliminary analysis
  16. Swift GRB 210722A: Global MASTER-Net observations report
  17. GRB 210702A: ALMA detection of mm-band rebrightening
  18. GRB 210722A: Assy optical detection
  19. GRB 210702A: ATCA detection of radio rebrightening
  20. GRB 210722A: Nanshan/NEXT optical afterglow observations
  21. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  22. Fermi trigger No 648602917: Global MASTER-Net observations report
  23. Fermi-LAT Gamma-ray Observations of IceCube-210717A
  24. GRB 210719A: GECAM detection
  25. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  26. Fermi trigger No 648359752: Global MASTER-Net observations report
  27. Fermi trigger No 648278666: Global MASTER-Net observations report
  28. IceCube-210717A: IceCube observation of a high-energy neutrino candidate track-like event
  29. Konus-Wind detection of GRB 210714A
  30. Fermi trigger No 647942198: MASTER optical afterglow detection
  31. GRB 210704A: Zeiss-1000/SAO-RAS optical observations
  32. GRB 210715B: DDOTI Upper Limits on the Afterglow
  33. Fermi trigger No 648033323: Global MASTER-Net observations report
  34. Fermi trigger No 648024201: Global MASTER-Net observations report
  35. Fermi trigger No 647942198: Global MASTER-Net observations report
  36. GRB 210712A: Swift-BAT refined analysis
  37. Recent activity of SGR 1935+2154 as observed by CGBM
  38. GRB 210712A: Swift-XRT refined Analysis
  39. GRB 210712A: Swift/UVOT Upper Limits
  40. GRB 210712A: BOOTES-3/YA optical upper limit
  41. Fermi trigger No 647805873: Global MASTER-Net observations report
  42. GRB 210712A: Enhanced Swift-XRT position
  43. GRB 210704A: classification as long GRB and redshift estimating
  44. GRB 210704A: Lowell Discovery Telescope Optical Observations
  45. Fermi trigger No 647775795: Global MASTER-Net observations report
  46. GRB 210712A: Swift detection of a burst
  47. GRB 210709A: AstroSat CZTI detection
  48. GRB 210704A: Continued Gemini-North NIR K-band Detections
  49. GRB 210704A: INTEGRAL observations
  50. GRB 210704A: NOT optical observations and color change
  51. GRB210704A: Gemini near-infrared upper limits
  52. Fermi trigger No 647653174: Global MASTER-Net observations report
  53. GRB 210704A: Assy optical afterglow upper limit
  54. Fermi trigger No 647641569: Global MASTER-Net observations report
  55. Fermi trigger No 647624281: Global MASTER-Net observations report
  56. GRB 210704A: OSIRIS/GTC Observations and Archival Detection of the Possible Host Galaxy
  57. MAXI GRB210709.93: Global MASTER-Net observations report
  58. Fermi trigger No 647522278: Global MASTER-Net observations report
  59. GRB 210704A: Gemini-North Infrared Source Detection
  60. GRB 210704A: further TNG optical observations
  61. GRB 210706A: Swift/XRT afterglow confirmation
  62. GRB 210708B: Swift-BAT refined analysis
  63. Fermi GRB 210709A: Global MASTER-Net observations report
  64. GRB 210709A: Fermi GBM Final Real-time Localization
  65. Swift GRB 210708B: Global MASTER-Net observations report
  66. GRB 210708A: Swift/UVOT Upper Limits
  67. GRB 210702A: ATCA detection
  68. GRB 210702A: ALMA detection
  69. GRB 210708A: Swift-BAT refined analysis
  70. Fermi GBM Sub-Threshold Detection of GRB 210708A
  71. Fermi GBM Sub-Threshold Detection of GRB 210707A
  72. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  73. GRB 210708B: Swift detection of a possible burst
  74. GRB 210708A: Swift-XRT refined Analysis
  75. GRB 210707A: A long GRB detected by INTEGRAL
  76. GRB 210708A: Swift detection of a burst
  77. Swift GRB210708.10: Global MASTER-Net observations report
  78. GRB 210704A: CAHA 2.2m telescope optical limit
  79. Fermi trigger No 647365516: Global MASTER-Net observations report
  80. Fermi trigger No 647271699: Global MASTER-Net observations report
  81. Fermi GBM Observations of SGR J1935+2154
  82. GRB 210706A: Fermi GBM observation
  83. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  84. Konus-Wind detection of GRB 210706A
  85. GRB 210706A: GIT optical upper limits
  86. GRB 210704A: OAJ T80 multi-color detections
  87. GRB 210706A: Swift-XRT afterglow detection
  88. Integral GRB210707.02: Global MASTER-Net observations report
  89. GRB 210706A: Swift ToO observations
  90. Fermi trigger No 647252274: Global MASTER-Net observations report
  91. Integral GRB210706.72: Global MASTER-Net observations report
  92. GRB 210706A: Swift/BAT-GUANO detection and arcminute localization
  93. GRB 210704A: OSIRIS/GTC spectroscopy
  94. GRB 210704A: CAHA 2.2m Afterglow Detection
  95. GRB 210704A: RATIR optical upper limits
  96. GRB 210704A: Swift/UVOT Upper Limits
  97. Konus-Wind detection of GRB 210704A
  98. GRB 210704B: AstroSat CZTI detection
  99. GRB 210619B: ALMA detection
  100. GRB 210704A: TNG detection of the optical afterglow candidate

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