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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"

11854 results found.

  1. GRB210731A: Enhanced Swift-XRT position
  2. Swift GRB210731.93: Global MASTER-Net observations report
  3. Fermi-LAT Gamma-ray Observations of IceCube-210730A
  4. GRB 210730A: BOOTES-5/JGT and 2.2m CAHA telescopes optical limit
  5. Fermi trigger No 649390368: Global MASTER-Net observations report
  6. GRB 210730A: AstroSat CZTI detection
  7. GRB 210730A: Swift-XRT refined Analysis
  8. GRB 210727A: AstroSat CZTI detection
  9. GRB 210726A: Deep CAHA 2.2m limit
  10. GRB 210714A: Fermi GBM observation
  11. GRB 210726A: Swift-XRT refined Analysis
  12. GRB 210727A: AGILE/MCAL detection
  13. GRB 210726A: CAHA 2.2m telescope optical limit
  14. GRB 210726A: Swift detection of a burst
  15. Swift GRB210726.80: Global MASTER-Net observations report
  16. Fermi trigger No 648959581: Global MASTER-Net observations report
  17. GRB 210725B: Swift-XRT refined Analysis
  18. GRB 210724A: Zeiss-1000 of Koshka observatory, optical upper limit
  19. GRB 210725A: Swift-XRT refined Analysis
  20. GRB 210724A: Swift-XRT refined Analysis
  21. GRB 210722A: continued Assy optical observations
  22. GRB 210722A: Nanshan/NEXT further optical observations
  23. Fermi trigger No 648868114: Global MASTER-Net observations report
  24. GRB 210725A: Swift detection of a burst
  25. GRB210724A: MeerLICHT upper limits
  26. GRB 210724A: Swift detection of a burst
  27. Swift GRB210724.84: Global MASTER-Net observations report
  28. GRB 210722A: continued Assy optical observations
  29. GRB 210722A: D50 optical detection
  30. GRB 210722A: Fermi GBM observation
  31. GRB 210722A: Swift-BAT refined analysis
  32. GRB 210722A: Kitab optical observations, light curve
  33. GRB 210723A: Swift detection of a burst
  34. GRB 210722A: Swift-XRT refined Analysis
  35. GRB 210722A: Swift/UVOT Detection
  36. GRB 210722A: GIT optical detection and preliminary analysis
  37. GRB 210702A: ALMA detection of mm-band rebrightening
  38. GRB 210722A: Assy optical detection
  39. GRB 210722A: Nanshan/NEXT optical afterglow observations
  40. GRB 210722A: Swift detection of a burst with a bright optical counterpart
  41. Fermi trigger No 648602917: Global MASTER-Net observations report
  42. Fermi-LAT Gamma-ray Observations of IceCube-210717A
  43. Fermi trigger No 648278666: Global MASTER-Net observations report
  44. Konus-Wind detection of GRB 210714A
  45. Fermi trigger No 648033323: Global MASTER-Net observations report
  46. Fermi trigger No 648024201: Global MASTER-Net observations report
  47. GRB 210712A: Swift-BAT refined analysis
  48. GECAM detection of a short burst from SGR J1935+2154
  49. Recent activity of SGR 1935+2154 as observed by CGBM
  50. GRB 210712A: Swift-XRT refined Analysis
  51. Fermi trigger No 647805873: Global MASTER-Net observations report
  52. GRB 210704A: classification as long GRB and redshift estimating
  53. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  54. GECAM detection of a short burst from SGR J1935+2154
  55. GRB 210712A: Swift detection of a burst
  56. GRB 210709A: AstroSat CZTI detection
  57. Fermi trigger No 647653174: Global MASTER-Net observations report
  58. GRB 210704A: Assy optical afterglow upper limit
  59. Fermi trigger No 647641569: Global MASTER-Net observations report
  60. Fermi trigger No 647624281: Global MASTER-Net observations report
  61. GECAM detection of a short burst from SGR J1935+2154
  62. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  63. GRB 210707A: A long GRB detected by INTEGRAL
  64. GRB 210704A: CAHA 2.2m telescope optical limit
  65. Fermi trigger No 647365516: Global MASTER-Net observations report
  66. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  67. GRB 210706A: optical upper limit of Sintesz-Newton/CrAO and AS-32/AbAO
  68. Konus-Wind detection of GRB 210706A
  69. Integral GRB210707.02: Global MASTER-Net observations report
  70. INTEGRAL detection of a burst from SGR 1935+2154
  71. Konus-Wind detection of GRB 210704A
  72. GRB 210704B: AstroSat CZTI detection
  73. GRB 210704A: Assy optical afterglow candidate
  74. GRB 210704A: AstroSat CZTI detection
  75. IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  76. GRB 210704A: Fermi-LAT detection
  77. Fermi trigger No 647108723: Global MASTER-Net observations report
  78. Fermi trigger No 647120009: Global MASTER-Net observations report
  79. Konus-Wind detection of GRB 210702A
  80. GRB 210702A: AGILE detection
  81. GRB 210619B: JCMT SCUBA-2 sub-mm observations
  82. GRB 210702A: VLT/X-shooter redshift
  83. Swift GRB 210702A: Global MASTER-Net observations report
  84. Swift GRB210702.80: Global MASTER-Net OT detection
  85. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  86. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  87. GRB 210627B: GECAM detection
  88. IceCube Alert 210629.76: Global MASTER-Net observations report
  89. GRB 210619B: Sayan observatory 1.6-m telescope observations
  90. GRB 210626A: CAHA 2.2m telescope optical limit
  91. GRB 210619B: Deep CAHA 2.2m detection and late-time light curve behavior
  92. Fermi GRB 210627B: Global MASTER-Net observations report
  93. GRB 210627B: BALROG localization (Fermi Trigger 646509445/ GRB 210627748)
  94. GRB 210627B: Fermi GBM Final Real-time Localization
  95. Fermi GRB 210627A: Global MASTER-Net observations report
  96. Fermi GRB 210626A: Global MASTER-Net observations report
  97. GRB 210626A: Swift/BAT-GUANO detection and arcminute localization
  98. Fermi trigger No 646189108: Global MASTER-Net observations report
  99. GRB 210619B: Mini-MegaTORTORA early optical observations
  100. GRB 210619B: possibility of lensed visible afterglow?

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