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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"

27974 results found.

  1. GRB 210205A: BOOTES-4/MET optical upper limit
  2. GRB 210205A: Enhanced Swift-XRT position
  3. GRB 210205A: Swift detection of a burst
  4. GRB 210204B: Fermi GBM Final Real-time Localization
  5. GRB 210204A: GECAM detection
  6. GRB 210204A: Fermi GBM Final Real-time Localization
  7. GRB 210202A: AGILE/MCAL detection
  8. GRB 210202A: Fermi GBM detection
  9. GRB 210202A: Fermi-LAT detection
  10. INTEGRAL detection of a short burst from SGR 1935+2154
  11. GRB 210202A: Fermi GBM Final Real-time Localization
  12. GRB 210131A: GECAM detection
  13. GRB 210129A: Insight-HXMT/HE detection
  14. Fermi GBM Observations of SGR J1935+2154
  15. Konus-Wind detection of two bright bursts from SGR 1935+2154
  16. GRB 140330A: Swift-XRT refined Analysis
  17. GRB 140320B: Swift-XRT refined Analysis
  18. GRB 140402A: Swift-XRT refined Analysis
  19. GRB 140104B: Swift-XRT refined Analysis
  20. GRB 210126A: AstroSat CZTI detection
  21. GRB 210124B: AstroSat CZTI detection
  22. GRB 210123A: AstroSat CZTI detection
  23. IPN triangulation of a bright burst from SGR 1935+2154
  24. GECAM detection of a short burst probably from SGR 1935+2154
  25. GRB 210127A: Fermi GBM Final Real-time Localization
  26. GRB 210120A: Fermi GBM detection
  27. Konus-Wind detection of GRB 210121A
  28. Konus-Wind detection of GRB 210124B
  29. GRB 210126A: GECAM detection
  30. IPN triangulation of GRB 210124B (short)
  31. GRB 210124B: Insight-HXMT/HE detection
  32. GRB 210123A: Fermi GBM Final Localization
  33. GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A
  34. GRB 210123A: Insight-HXMT/HE detection
  35. IPN triangulation of GRB 210121A
  36. GRB 210121A: GECAM detection
  37. GRB 210121A: Insight-HXMT/HE detection
  38. ZTF21aaeyldq: GROND and CAHA jet break confirmation
  39. ZTF20aaeyldq: VLA radio detection
  40. GRB 210116A: AstroSat CZTI detection
  41. GRB 210116: AstroSat LAXPC detection
  42. GRB 210120A: MASTER OT (possibly) discovery
  43. GRB 210120A: Fermi GBM Final Real-time Localization
  44. GRB 210112A: 3.6m DOT optical detection
  45. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  46. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  47. GRB 210119A: Insight-HXMT/HE detection
  48. GRB 210119A: Fermi GBM observation
  49. ZTF21aaeyldq: LBT near-infrared observations
  50. GRB 210112A: Insight-HXMT/HE detection
  51. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  52. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  53. GRB 210119A: Fermi GBM Final Real-time Localization
  54. ZTF21aaeyldq CAHA 2.2m detection and power-law decay
  55. GRB 200613A: Host galaxy redshift from OSIRIS/GTC
  56. GRB 210112A: Deep CAHA 2.2m detection
  57. GRB 210104A: Late-time CAHA 2.2m detection
  58. Konus-Wind detection of GRB 210112A
  59. ZTF21aaeyldq (AT2021any): Detection of X-ray Emission with Swift/XRT
  60. ZTF21aaeyldq: 2.2m CAHA BVRI optical observations
  61. ZTF21aaeyldq: NOT optical observations
  62. ZTF21aaeyldq: observations with the 3.6m Devasthal Optical Telescope
  63. ZTF21aaeyldq: GTC Redshift and GRB afterglow nature confirmation
  64. ZTF Discovery of ZTF21aaeyldq (AT2021any): a Hostless, Young, and Rapidly Fading Transient
  65. GRB 210104A: JCMT SCUBA-2 sub-mm observations
  66. GRB 210112A: Swift/UVOT Detection
  67. GRB 210112A: Mondy optical observations
  68. GRB 210112A: 1.3m DFOT Optical upper limit
  69. GRB 210112A: OSN second epoch, decay
  70. GRB 210104A: AstroSat CZTI detection
  71. NuEm-210111A: MAXI/GSC upper limit
  72. GRB 210112A: Swift-BAT refined analysis
  73. GRB 210112A: OSN Reddened Afterglow Detection
  74. GRB 210112A: Swift-XRT refined Analysis
  75. NuEm-210111A : No neutrino counterpart in ANTARES
  76. GRB 210112A: AGILE detection
  77. GRB 210112A: Kitab a optical upper limit
  78. GRB 210104A: AROMA-N Optical Afterglow Detection
  79. GRB 210112A: Enhanced Swift-XRT position
  80. GRB 210112A: Swift detection of a burst with an optical counterpart
  81. GRB 210110A: MAXI/GSC detection
  82. GRB 210109A: MAXI/GSC detection
  83. Correction to GCN 29278: GRB 201216C XRT refined analysis
  84. GRB 201216C: Swift-XRT refined Analysis
  85. GRB 201227A: ASIM observation
  86. GRB210104A: VIRT optical transient detection.
  87. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  88. GRB 210102B: further Swift-XRT observations
  89. GRB 210104A: CALET Gamma-Ray Burst Monitor detection
  90. GRB 210104B: Swift-BAT refined analysis
  91. GW170817: HST observations at 3.4 years from merger
  92. GRB 210104A: early ATLAS detections of the bright afterglow
  93. GRB 210105A: Fermi GBM Final Real-time Localization
  94. GRB 210104A: Swift-XRT refined Analysis
  95. GRB 210104B: Swift/UVOT Upper Limits
  96. Konus-Wind detection of GRB 210104A
  97. GRB 210104A: 1.3m DFOT Optical Afterglow Detection
  98. GRB 210104B: Swift-XRT refined Analysis
  99. GRB 210104B: Enhanced Swift-XRT position
  100. GRB 210104A: Swift-BAT refined analysis

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