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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"

14992 results found.

  1. GRB 210120A: Fermi GBM detection
  2. Konus-Wind detection of GRB 210121A
  3. Konus-Wind detection of GRB 210124B
  4. GRB 210126A: GECAM detection
  5. IPN triangulation of GRB 210124B (short)
  6. GRB 210124B: Insight-HXMT/HE detection
  7. GRB 210123A: Fermi GBM Final Localization
  8. GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A
  9. GRB 210123A: Insight-HXMT/HE detection
  10. IPN triangulation of GRB 210121A
  11. GRB 210121A: GECAM detection
  12. GRB 210121A: Insight-HXMT/HE detection
  13. ZTF21aaeyldq: GROND and CAHA jet break confirmation
  14. ZTF20aaeyldq: VLA radio detection
  15. GRB 210116A: AstroSat CZTI detection
  16. GRB 210116: AstroSat LAXPC detection
  17. GRB 210120A: MASTER OT (possibly) discovery
  18. GECAM In-Flight Trigger of GRB 210120A
  19. GRB 210120A: Fermi GBM Final Real-time Localization
  20. GRB 210112A: 3.6m DOT optical detection
  21. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  22. GRB 210119A: Insight-HXMT/HE detection
  23. ZTF21aaeyldq: LBT near-infrared observations
  24. GRB 210112A: Insight-HXMT/HE detection
  25. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  26. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  27. GRB 210119A: Fermi GBM Final Real-time Localization
  28. ZTF21aaeyldq CAHA 2.2m detection and power-law decay
  29. GRB 200613A: Host galaxy redshift from OSIRIS/GTC
  30. GRB 210112A: Deep CAHA 2.2m detection
  31. GRB 210104A: Late-time CAHA 2.2m detection
  32. ZTF21aaeyldq: KPED observations
  33. Konus-Wind detection of GRB 210112A
  34. ZTF21aaeyldq (AT2021any): Detection of X-ray Emission with Swift/XRT
  35. ZTF21aaeyldq: 2.2m CAHA BVRI optical observations
  36. ZTF21aaeyldq: NOT optical observations
  37. ZTF21aaeyldq: Lowell Discovery Telescope observations
  38. ZTF21aaeyldq: observations with the 3.6m Devasthal Optical Telescope
  39. ZTF21aaeyldq: GTC Redshift and GRB afterglow nature confirmation
  40. ZTF Discovery of ZTF21aaeyldq (AT2021any): a Hostless, Young, and Rapidly Fading Transient
  41. GRB 210112A: Swift/UVOT Detection
  42. GRB 210112A: Mondy optical observations
  43. GRB 210112A: OSN second epoch, decay
  44. GRB 210104A: AstroSat CZTI detection
  45. NuEm-210111A: MAXI/GSC upper limit
  46. GRB 210112A: OSN Reddened Afterglow Detection
  47. NuEm-210111A : No neutrino counterpart in ANTARES
  48. GRB 210112A: AGILE detection
  49. GRB 210104A: AROMA-N Optical Afterglow Detection
  50. GRB 210112A: Swift detection of a burst with an optical counterpart
  51. GRB 210110A: MAXI/GSC detection
  52. GRB 210109A: MAXI/GSC detection
  53. GRB 201227A: ASIM observation
  54. GRB210104A: VIRT optical transient detection.
  55. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  56. GRB 210102B: further Swift-XRT observations
  57. GRB 210104A: CALET Gamma-Ray Burst Monitor detection
  58. GW170817: HST observations at 3.4 years from merger
  59. GRB 210105A: Fermi GBM Final Real-time Localization
  60. Konus-Wind detection of GRB 210104A
  61. GRB 210104A: 1.3m DFOT Optical Afterglow Detection
  62. GRB 210104A: MASTER OT rebrightening detection
  63. GRB 210104A: Swift/UVOT Detection
  64. GRB 210104A: Fermi GBM detection
  65. GRB 210104B: Swift detection of a burst
  66. GRB 210104A: BOOTES-4/MET early optical afterglow detection
  67. GRB 210104A: Swift detection of a burst with a bright optical counterpart
  68. GRB 210104A: Fermi GBM Final Real-time Localization
  69. GRB 210102C: Fermi GBM detection
  70. GRB 210102C: Swift detection of a burst
  71. GRB 210102B: MAXI/GSC detection
  72. Swift Trigger 1015615 is not a GRB
  73. GRB 210101A: Fermi GBM Final Real-time Localization
  74. GRB 201229A: Swift/UVOT Detection
  75. GRB 201227A: Fermi GBM observation
  76. GRB 201229A: AbAO optical afterglow detection, TSHAO optical upper limit
  77. Konus-Wind observation of GRB 201227A
  78. GRB 201229B: Fermi GBM Final Real-time Localization
  79. GRB 201229A: Swift detection of a burst with a possible optical counterpart
  80. GRB 201228B: Fermi GBM Final Real-time Localization
  81. GRB 201227A: Insight-HXMT/HE detection
  82. GRB 201226A: Insight-HXMT/HE detection
  83. GRB 201228A: Fermi GBM Final Real-time Localization
  84. IPN triangulation of GRB 201227A (short)
  85. GRB 201227A: AGILE detection of a burst
  86. GRB 201223A: Swift/UVOT Detection
  87. GRB 201223A: Fermi GBM Detection
  88. GRB 201223A: BOOTES-4/MET early optical observation
  89. GRB 201223A: Nanshan/NEXT early optical afterglow detection
  90. GRB 201223A: Swift detection of a burst with a bright optical counterpart
  91. Swift GRB201223.75: Global MASTER-Net OT detection
  92. IceCube-201222A: No significant detection in HAWC
  93. IceCube-201221A: No significant detection in HAWC
  94. GRB 201221A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  95. GRB 201221A: REM early-time afterglow detection
  96. GRB 201221B: Insight-HXMT/HE detection
  97. IceCube-201221A: Upper limits from Insight-HXMT/HE observations
  98. GRB 201221D: MMT MMIRS detection of marginally extended source
  99. GRB 201221D: Fermi GBM detection
  100. GRB 201221D: Archival PS1 Imaging of the Putative Host Galaxy

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