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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"

11848 results found.

  1. GRB 210730A: Swift-XRT refined Analysis
  2. GRB 210727A: AstroSat CZTI detection
  3. GRB 210726A: Deep CAHA 2.2m limit
  4. GRB 210714A: Fermi GBM observation
  5. GRB 210726A: Swift-XRT refined Analysis
  6. GRB 210727A: AGILE/MCAL detection
  7. GRB 210726A: CAHA 2.2m telescope optical limit
  8. GRB 210726A: Swift detection of a burst
  9. Swift GRB210726.80: Global MASTER-Net observations report
  10. Fermi trigger No 648959581: Global MASTER-Net observations report
  11. GRB 210725B: Swift-XRT refined Analysis
  12. GRB 210724A: Zeiss-1000 of Koshka observatory, optical upper limit
  13. GRB 210725A: Swift-XRT refined Analysis
  14. GRB 210724A: Swift-XRT refined Analysis
  15. GRB 210722A: continued Assy optical observations
  16. GRB 210722A: Nanshan/NEXT further optical observations
  17. Fermi trigger No 648868114: Global MASTER-Net observations report
  18. GRB 210725A: Swift detection of a burst
  19. GRB210724A: MeerLICHT upper limits
  20. GRB 210724A: Swift detection of a burst
  21. Swift GRB210724.84: Global MASTER-Net observations report
  22. GRB 210722A: continued Assy optical observations
  23. GRB 210722A: D50 optical detection
  24. GRB 210722A: Fermi GBM observation
  25. GRB 210722A: Swift-BAT refined analysis
  26. GRB 210722A: Kitab optical observations, light curve
  27. GRB 210723A: Swift detection of a burst
  28. GRB 210722A: Swift-XRT refined Analysis
  29. GRB 210722A: Swift/UVOT Detection
  30. GRB 210722A: GIT optical detection and preliminary analysis
  31. GRB 210702A: ALMA detection of mm-band rebrightening
  32. GRB 210722A: Assy optical detection
  33. GRB 210722A: Nanshan/NEXT optical afterglow observations
  34. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  35. Fermi trigger No 648602917: Global MASTER-Net observations report
  36. Fermi-LAT Gamma-ray Observations of IceCube-210717A
  37. Fermi trigger No 648278666: Global MASTER-Net observations report
  38. Konus-Wind detection of GRB 210714A
  39. Fermi trigger No 648033323: Global MASTER-Net observations report
  40. Fermi trigger No 648024201: Global MASTER-Net observations report
  41. GRB 210712A: Swift-BAT refined analysis
  42. GECAM detection of a short burst from SGR J1935+2154
  43. Recent activity of SGR 1935+2154 as observed by CGBM
  44. GRB 210712A: Swift-XRT refined Analysis
  45. Fermi trigger No 647805873: Global MASTER-Net observations report
  46. GRB 210704A: classification as long GRB and redshift estimating
  47. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  48. GECAM detection of a short burst from SGR J1935+2154
  49. GRB 210712A: Swift detection of a burst
  50. GRB 210709A: AstroSat CZTI detection
  51. Fermi trigger No 647653174: Global MASTER-Net observations report
  52. GRB 210704A: Assy optical afterglow upper limit
  53. Fermi trigger No 647641569: Global MASTER-Net observations report
  54. Fermi trigger No 647624281: Global MASTER-Net observations report
  55. GECAM detection of a short burst from SGR J1935+2154
  56. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  57. GRB 210707A: A long GRB detected by INTEGRAL
  58. GRB 210704A: CAHA 2.2m telescope optical limit
  59. Fermi trigger No 647365516: Global MASTER-Net observations report
  60. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  61. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  62. Konus-Wind detection of GRB 210706A
  63. Integral GRB210707.02: Global MASTER-Net observations report
  64. INTEGRAL detection of a burst from SGR 1935+2154
  65. Konus-Wind detection of GRB 210704A
  66. GRB 210704B: AstroSat CZTI detection
  67. GRB 210704A: Assy optical afterglow candidate
  68. GRB 210704A: AstroSat CZTI detection
  69. IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  70. GRB 210704A: Fermi-LAT detection
  71. Fermi trigger No 647108723: Global MASTER-Net observations report
  72. Fermi trigger No 647120009: Global MASTER-Net observations report
  73. Konus-Wind detection of GRB 210702A
  74. GRB 210702A: AGILE detection
  75. GRB 210619B: JCMT SCUBA-2 sub-mm observations
  76. GRB 210702A: VLT/X-shooter redshift
  77. Swift GRB 210702A: Global MASTER-Net observations report
  78. Swift GRB210702.80: Global MASTER-Net OT detection
  79. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  80. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  81. GRB 210627B: GECAM detection
  82. IceCube Alert 210629.76: Global MASTER-Net observations report
  83. GRB 210619B: Sayan observatory 1.6-m telescope observations
  84. GRB 210626A: CAHA 2.2m telescope optical limit
  85. GRB 210619B: Deep CAHA 2.2m detection and late-time light curve behavior
  86. Fermi GRB 210627B: Global MASTER-Net observations report
  87. GRB 210627B: BALROG localization (Fermi Trigger 646509445/ GRB 210627748)
  88. GRB 210627B: Fermi GBM Final Real-time Localization
  89. Fermi GRB 210627A: Global MASTER-Net observations report
  90. Fermi GRB 210626A: Global MASTER-Net observations report
  91. GRB 210626A: Swift/BAT-GUANO detection and arcminute localization
  92. Fermi trigger No 646189108: Global MASTER-Net observations report
  93. GRB 210619B: Mini-MegaTORTORA early optical observations
  94. GRB 210619B: possibility of lensed visible afterglow?
  95. Swift GRB210621.71: Global MASTER-Net observations report
  96. GRB 210619B: 1.5m OSN optical observation
  97. GRB 210619B: iTelescope optical afterglow observation
  98. GRB 210619B: SAO RAS optical observations
  99. GRB 210619B: REM optical/NIR afterglow detection
  100. GRB 210619B: Liverpool Telescope First Hour Observations

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