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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"

14950 results found.

  1. GRB 230709C: Fermi GBM Detection
  2. GRB 230709C: Fermi GBM Final Localization
  3. GRB 230710A: Fermi GBM Final Real-time Localization
  4. IceCube-230707A: No candidates detected by Swift-XRT
  5. GRB 230709C: AstroSat CZTI detection
  6. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  7. GRB 230628C: GRID Detection
  8. IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
  9. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  10. IceCube-230707B - IceCube observation of a high-energy neutrino candidate track-like event
  11. GRB 230707B: Fermi GBM Final Real-time Localization
  12. IceCube-230707A - IceCube observation of a high-energy neutrino candidate track-like event
  13. GRB 230707A: Fermi GBM Detection
  14. GRB 230707A: Fermi GBM Final Real-time Localization
  15. GRB 230625A: Detection by GRID
  16. ZTF23aaoohpy/AT2023lcr: AMI-LA radio detection
  17. GRB 230626A: VZLUSAT-2 detection
  18. GRB 230328B: LBT detection of the likely host galaxy
  19. Konus-Wind detection of GRB 220623A
  20. GRB 230701B: AstroSat CZTI detection
  21. GRB 230628E: Swift/UVOT Detection
  22. GRB 230702A: Fermi GBM Final Real-time Localization
  23. GRB 230701A: Fermi GBM Final Real-time Localization
  24. IPN triangulation of GRB 230625B (ultra-long)
  25. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): ALMA 100 GHz Detection
  26. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  27. GRB 230625B: AstroSat CZTI detection
  28. GRB230628E: VLT optical identification of afterglow candidate
  29. GRB 230628E: Swift detection of a burst
  30. GRB 230628D: Fermi GBM Final Real-time Localization
  31. GRB 230628C: Fermi GBM Final Real-time Localization
  32. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  33. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  34. ZTF23aaoohpy /AT2023lcr: TNG NIR detection
  35. GRB 230628A: Fermi GBM Final Localization
  36. LIGO/Virgo/KAGRA S230627c: Additional observations from the Zwicky Transient Facility
  37. GRB 230626A: GRBAlpha detection
  38. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  39. GRB230626A: Fermi GBM Detection
  40. Konus-Wind detection of GRB 230616A
  41. LIGO/Virgo/KAGRA S230627c: Zwicky Transient Facility observations and candidates
  42. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  43. GRB 230625A: Fermi GBM Final Real-time Localization
  44. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  45. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  46. MAXI GRB 230623A: MASTER optical observations
  47. GRB 230623A: MAXI/GSC detection
  48. ZTF23aaoohpy/AT2023lcr: SAO RAS observations
  49. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  50. GRB 230622A: Swift detection of a burst
  51. GRB 230621A: Fermi GBM Final Localization Correction
  52. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  53. AT2023lcr: VLA radio detection
  54. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  55. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  56. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  57. IPN triangulation of GRB 230616A (short)
  58. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
  59. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  60. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  61. ZTF23aaoohpy/AT2023lcr: GOTO early optical observations and constraint
  62. ZTF23aaoohpy/AT2023lcr: Zwicky Transient Facility discovery of a fast fading red transient
  63. LIGO/Virgo/KAGRA S230615az: GRANDMA observations of GOTO and GIT candidates
  64. GRB 230618B: Fermi GBM Final Real-time Localization
  65. GRB 230618A: Swift detection of a burst
  66. GRB 230617A: Fermi GBM Final Real-time Localization
  67. LIGO/Virgo/KAGRA S230615az: Non-Detections of GROWTH-India Candidates from GECKO Optical Observations
  68. GRB 230614C: GRBAlpha detection
  69. GRB 230616A: AstroSat CZTI detection
  70. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  71. GRB 230614C: AstroSat CZTI detection
  72. GRB 230614C: Fermi GBM Detection
  73. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  74. GRB 230614B: Fermi GBM Final Real-time Localization
  75. GRB 230614A: Fermi GBM Final Real-time Localization
  76. GRB 230608A: CALET Gamma-Ray Burst Monitor detection
  77. GRB 230608A: AstroSat CZTI detection
  78. GRB 230608A: AGILE detection
  79. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  80. GRB 230606A: BOOTES-5/JGT optical upper limit
  81. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  82. GRB 230604A: GRBAlpha detection
  83. GRB 230606A: Swift detection of a burst
  84. Super-Kamiokande: Neutrino search for SN2023ixf
  85. GRB 230604A: AstroSat CZTI detection of a short GRB
  86. IceCube-230603A - IceCube observation of a high-energy neutrino candidate track-like event
  87. GRB 230603A: Fermi GBM Final Real-time Localization
  88. GRB 230521A: VZLUSAT-2 detection
  89. GRB 230522A: GRBAlpha and VZLUSAT-2 joint detection
  90. GRB 230525A: CALET Gamma-Ray Burst Monitor detection
  91. LIGO/Virgo/KAGRA S230529ay: Zwicky Transient Facility observations
  92. LIGO/Virgo/KAGRA S230528a: Zwicky Transient Facility observations
  93. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  94. LIGO/Virgo/KAGRA S230529ay: AstroSat CZTI non-detection and upper limits
  95. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  96. GRB 230529A: Fermi GBM Final Real-time Localization
  97. GRB 230525A: Fermi GBM Detection
  98. GRB 230525A: Fermi GBM Final Localization
  99. GRB 230523B: GRBAlpha detection
  100. LIGO/Virgo/KAGRA S230524x: Retraction of GW compact binary merger candidate

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