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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"

7455 results found.

  1. GRB 201020B: Swift ToO observations
  2. IceCube-201021A: IceCube observation of a high-energy neutrino candidate event
  3. GRB 201020A: Swift detection of a burst with an optical counterpart.
  4. GRB 201015A: 6 GHz VLA radio afterglow candidate detection
  5. GRB 201013A: 3.6m DOT Optical Observations
  6. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection
  7. GRB 201017A: Swift detection of a burst
  8. GRB 201015A: NOT optical afterglow confirmation
  9. IceCube-201014A: No neutrino counterpart candidates in ANTARES search
  10. Swift Trigger 1000255 is probably not a GRB
  11. IceCube-201014A: Not observable by GBM
  12. IceCube-201014A - IceCube observation of a high-energy neutrino candidate track-like event
  13. GRB 201013A: FRAM-ORM possible afterglow candidate
  14. GRB 201013A: Swift/UVOT Upper Limits
  15. IceCube-201007A: No candidate counterparts from the Zwicky Transient Facility
  16. GRB 201013A: Swift detection of a burst
  17. Swift detection of a new SGR 1830-0645 or a short GRB 201010A
  18. GRB 201008A: Swift ToO observations
  19. IceCube-201007A: Upper limits from Fermi-GBM Observations
  20. IceCube-201007A - IceCube observation of a high-energy neutrino candidate track-like event
  21. GRB 201006A: Swift detection of a burst
  22. IceCube-200926A: No candidate counterparts from the Zwicky Transient Facility
  23. GRB 201001A: Swift detection of a burst
  24. IceCube-200929A: Upper limits from Fermi-GBM Observations
  25. IceCube-200929A: No neutrino counterpart candidates in ANTARES search
  26. IceCube-200929A: IceCube observation of a high-energy neutrino candidate event
  27. IceCube-200926B: Upper limits from Fermi-GBM Observations
  28. IceCube-200926A: Upper limits from Fermi-GBM Observations
  29. IceCube-200926A: No Candidate Counterparts from the Zwicky Transient Facility
  30. IceCube-200926B: No neutrino counterpart candidates in ANTARES search
  31. IceCube-200926B: IceCube observation of a high-energy neutrino candidate event
  32. IceCube-200926A: IceCube observation of a high-energy neutrino candidate event
  33. Swift GRB 200925B: Global MASTER-Net OT detection
  34. GRB 200925B: OSN Afterglow Candidate Discovery
  35. GRB 200925B: Swift detection of a burst
  36. IceCube-200921A: Upper limits from Fermi-GBM Observations
  37. IceCube-200921A: IceCube observation of a high-energy neutrino candidate event
  38. IceCube-200916A - ZTF20acaapwk/SN2020tno classified as SN Ia
  39. IceCube-200916A: AbAO observations of optical candidates ZTF20acaapwk/AT2020tno, ZTF20acaapwo/AT2020tnp
  40. IceCube-200916A: No neutrino counterpart candidates in ANTARES search
  41. IceCube-200916A: Two Candidate Counterparts from the Zwicky Transient Facility
  42. IceCube-200916A: Upper limits from Fermi-GBM Observations
  43. GRB 200917A: Swift detection of a burst
  44. IceCube-200916A - IceCube observation of a high-energy neutrino candidate track-like event
  45. GRB 200914A: Swift ToO observations
  46. IceCube-200911A: No neutrino counterpart candidates in ANTARES search
  47. IceCube-200911A: not observable by Fermi-GBM
  48. IceCube-200911A: IceCube observation of a high-energy neutrino candidate event
  49. GRB 200907B: Swift detection of a short burst
  50. GRB 200906A: Swift detection of a burst
  51. ZTF20abtxwfx/AT2020sev : AstroSat CZTI non-detection of a transient
  52. GRB 200901B: Swift detection of a burst
  53. GRB 200826A: Lowell Discovery Telescope observations of ZTF20abwysqy
  54. GRB 200829A: Swift detection of a burst with an optical afterglow
  55. Zwicky Transient Facility discovery of ZTF20abtxwfx/AT2020sev, a fast optical transient and candidate afterglow
  56. GRB 200826A: VLA Detection at 6 GHz
  57. GRB200826A: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi Short GRB (Trigger 620108997)
  58. GRB200826A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 620108997)
  59. GRB 200826A: Tiled Swift observations
  60. Swift Trigger 992444: a possible GRB 200821A
  61. GRB 200819A: Swift detection of a burst
  62. Swift trigger 990358 is not an astrophysical source
  63. Swift trigger 989458 is likely not an astrophysical source
  64. GRB 200809B: Swift ToO observations
  65. IceCube-200806A: Upper limits from Fermi-GBM Observations
  66. GRB 200806A: Swift detection of a burst
  67. IceCube-200806A: IceCube observation of a high-energy neutrino candidate event
  68. GRB 200803A: Fermi GBM detection
  69. GRB 200803A: Tiled Swift observations
  70. Konus-Wind detection of GRB 200729A
  71. Fermi-GBM Sub-Threshold candidate for GRB 200729A
  72. GRB 200729A: NOT optical upper limits
  73. GRB 200729A: Swift detection of a burst
  74. GRB 200723A: ATLAS observations of GOTO candidate AT2020qer
  75. GRB 200723A: Swift ToO observations
  76. GRB 200723A: GOTO candidate afterglow and host galaxy
  77. AMON IC_HAWC 170720: No Neutrino Counterpart detected with ANTARES
  78. GRB 200716C: Optical observations from HCT
  79. GRB 200522A: HST NIR counterpart confirmation
  80. GRB 200716C: Swift detection of a burst with an optical counterpart
  81. GRB 200715A: Swift ToO observations
  82. GRB 200714E: Swift ToO observations
  83. GRB 200522A: Candidate Optical/nIR Counterpart from Gemini and HST Imaging
  84. GRB 200713A: Swift detection of a burst
  85. GRB 200711A: KAIT Optical Upper Limit
  86. GRB 200711A: Swift detection of a burst
  87. GRB 200709B/HAWC-200907A: Swift-XRT further observations
  88. HAWC-200907A: No Neutrino Counterpart detected with ANTARES
  89. GRB 200709B: Tiled Swift observations
  90. Trigger 980513: Swift detection of SGR Swift J1818.0-1607
  91. GRB 200630A: Swift detection of a burst
  92. GRB 200623A: Further MMTCam Observations of XRT Source #3
  93. GRB 200623A: LBT optical observations
  94. GRB 200625A: Swift ToO observations
  95. GRB 200623A: Swift/UVOT Upper Limits
  96. GRB 200623A: OAJ deep multi-color imaging, XRT #2 is pre-detected
  97. GRB 200623A: TNG optical observations
  98. GRB 200623A: AbAO afterglow candidate within XRT #2
  99. GRB 200623A: Swift ToO observations
  100. IceCube-200620A: MASTER previous detection of ZTF20abgvabi/AT2020ncr

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