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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"

11559 results found.

  1. GRB 210228A: GECAM detection
  2. Fermi trigger No 636168178: Global MASTER-Net observations report
  3. GRB 210225A: Insight-HXMT/HE detection
  4. GRB 210226A: Fermi GBM detection
  5. Fermi trigger No 635922820: Global MASTER-Net observations report
  6. Fermi GBM Sub-Threshold Detection of GRB 210217A
  7. Fermi/GBM observation of a burst from SGR 1830-0645
  8. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Assy and Mondy optical observations
  9. GRB 210211A: ePESSTO+ NTT optical observations
  10. Fermi GRB 210213A: Global MASTER-Net observations report
  11. GRB 210213A: Fermi GBM Final Real-time Localization
  12. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued CrAO and AbAO optical observations
  13. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  14. GRB 210211A: Fermi GBM observation
  15. GRB 210210A as a BdHN II
  16. Fermi-LAT Gamma-ray Observations of IceCube-210210A
  17. GRB 210211A: Fermi GBM Final Real-time Localization
  18. Fermi trigger No 634659312: Global MASTER-Net observations report
  19. Fermi GRB 210210B: Global MASTER-Net observations report
  20. IceCube-210210A: Upper limits from Fermi-GBM Observations
  21. GRB 210210B: Fermi GBM Final Real-time Localization
  22. IceCube-210210A: IceCube observation of a high-energy neutrino candidate event
  23. ZTF21aahifke/AT2021clk: ZTF discovery of an optical fast transient (possible afterglow)
  24. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Mondy optical observations
  25. GRB 210204A: LBT observations and jet break
  26. GRB 210204A: redshift revision of ZTF21aagwbjr/AT2021buv (correction to GCN 29411)
  27. Fermi GRB 210207A: Global MASTER-Net observations report
  28. GRB 210207A: BALROG localization (Fermi Trigger / GRB 210207603)
  29. GRB 210204A (ZTF21aagwbjr/AT2021buv): Mondy and AbAO optical observations
  30. GRB 210207A: Fermi GBM Final Real-time Localization
  31. Konus-Wind detection of GRB 210204A / ZTF21aagwbjr
  32. GRB 210204A: Optical Observations from HCT
  33. GRB 210204A / ZTF21aagwbjr: Swift-XRT observations
  34. GRB 210204A: Swift ToO observations
  35. VLT/X-shooter redshift of 1.466 for ZTF21aagwbjr/AT2021buv, strengthening its association with GRB 210204A
  36. GRB 210204A: AstroSat CZTI Detection
  37. IPN triangulation of GRB 210204A
  38. ZTF21aagwbjr/AT2021buv: ZTF discovery of a fast optical transient likely associated with GRB 210104A
  39. Fermi GRB 210204B: Global MASTER-Net observations report
  40. Fermi GRB 210204A: Global MASTER-Net observations report
  41. GRB 210204B: Fermi GBM Final Real-time Localization
  42. GRB 210204: Fermi GBM observation
  43. GRB 210204A: GECAM detection
  44. GRB 210204A: BALROG localization (Fermi Trigger 634112970 / GRB 210204270)
  45. GRB 210204A: Fermi GBM Final Real-time Localization
  46. GRB 210202A: AGILE/MCAL detection
  47. Fermi GBM Observations of a bright burst from SGR J1935+2154
  48. GRB 210202A: Fermi GBM detection
  49. GRB 210202A: Fermi-LAT detection
  50. Fermi GRB 210202A: Global MASTER-Net observations report
  51. Fermi trigger No 633963272: Global MASTER-Net observations report
  52. Recent activity of SGR 1935+2154 as observed by CGBM
  53. GRB 210202A: BALROG localization (Fermi Trigger / GRB 210202841)
  54. GRB 210202A: Fermi GBM Final Real-time Localization
  55. Fermi trigger No 633879387: Global MASTER-Net observations report
  56. Fermi GBM Observations of SGR J1935+2154
  57. GRB 140330A: Swift-XRT refined Analysis
  58. GRB 140402A: Swift-XRT refined Analysis
  59. GRB 140104B: Swift-XRT refined Analysis
  60. GRB 210126A: AstroSat CZTI detection
  61. GRB 210123A: AstroSat CZTI detection
  62. GRB 210127A: Fermi GBM Final Real-time Localization
  63. GRB 210120A: Fermi GBM detection
  64. Fermi trigger No 633348010: Global MASTER-Net observations report
  65. GRB 210126A: GECAM detection
  66. GRB 210126A: BALROG localization (Fermi Trigger / GRB 210126417)
  67. Fermi trigger No 633257525: Global MASTER-Net observations report
  68. GRB 210123A: Fermi GBM Final Localization
  69. GRB 210120A : 1.3m DFOT optical observations
  70. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  71. GRB 210120A: MASTER OT (possibly) discovery
  72. GECAM In-Flight Trigger of GRB 210120A
  73. Fermi GRB 210120A: Global MASTER-Net observations report
  74. GRB 210120A: BALROG localization (Fermi Trigger 632819449 / GRB 210120299)
  75. GRB 210120A: Fermi GBM Final Real-time Localization
  76. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  77. GRB 210119A: Insight-HXMT/HE detection
  78. GRB 210119A: Fermi GBM observation
  79. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  80. Fermi GRB 210119A: Global MASTER-Net observations report
  81. GRB 210119A: Fermi GBM Final Real-time Localization
  82. GRB 200613A: Host galaxy redshift from OSIRIS/GTC
  83. GRB 210104A: Late-time CAHA 2.2m detection
  84. Fermi trigger No 632573937: Global MASTER-Net observations report
  85. GRB 210104A: AstroSat CZTI detection
  86. GRB 210104A: Mondy optical observations, light curve
  87. GRB 210104A: Assy continued optical observations, correction to GCN circ. 29265
  88. GRB 210108A: BALROG localization (Fermi Trigger 631793415 / GRB 210108424)
  89. GRB 210104A: SAO RAS optical observations
  90. GRB 201227A: ASIM observation
  91. GRB210104A: VIRT optical transient detection.
  92. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  93. Fermi trigger No 631602681: Global MASTER-Net observations report
  94. GRB 210104A: CALET Gamma-Ray Burst Monitor detection
  95. Fermi trigger No 631584650: Global MASTER-Net observations report
  96. GRB 210104A: Assy continued optical observations
  97. Fermi GRB 210105A: Global MASTER-Net observations report
  98. GRB 210105A: Fermi GBM Final Real-time Localization
  99. Konus-Wind detection of GRB 210104A
  100. GRB 210104A: 1.3m DFOT Optical Afterglow Detection

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