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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"

28255 results found.

  1. GRB 230707A: Swift-XRT observations
  2. IceCube-230707B - IceCube observation of a high-energy neutrino candidate track-like event
  3. GRB 230707B: Fermi GBM Final Real-time Localization
  4. IceCube-230707A - IceCube observation of a high-energy neutrino candidate track-like event
  5. GRB 230707A: Fermi GBM Detection
  6. GRB 230707A: Swift ToO observations
  7. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  8. GRB 230707A: Fermi GBM Final Real-time Localization
  9. GRB 230625A: Detection by GRID
  10. ZTF23aaoohpy/AT2023lcr: AMI-LA radio detection
  11. GRB 230626A: VZLUSAT-2 detection
  12. GRB 230328B: LBT detection of the likely host galaxy
  13. Konus-Wind detection of GRB 220623A
  14. GRB 230701B: AstroSat CZTI detection
  15. GRB 230628E: Swift/UVOT Detection
  16. GRB 230702A: Fermi GBM Final Real-time Localization
  17. GRB 230628E: ATCA rapid radio follow-up
  18. GRB 230701A: Fermi GBM Final Real-time Localization
  19. IPN triangulation of GRB 230625B (ultra-long)
  20. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): ALMA 100 GHz Detection
  21. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  22. GRB 230628E - VLT spectroscopic observations
  23. GRB 230625B: AstroSat CZTI detection
  24. GRB230628E: VLT optical identification of afterglow candidate
  25. GRB 230628E: Swift-XRT refined Analysis
  26. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  27. GRB 230628A: Enhanced Swift-XRT position
  28. GRB 230628E: LCOGT Optical Upper Limit
  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 230623A: Swift-XRT observations
  44. GRB 230625A: Fermi GBM Final Real-time Localization
  45. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  46. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  47. GRB 230623A: Tiled Swift observations
  48. MAXI GRB 230623A: MASTER optical observations
  49. GRB 230623A: Tiled Swift observations
  50. GRB 230622A: ATCA rapid radio follow-up
  51. GRB 230622A: Swift-XRT refined Analysis
  52. GRB 230623A: MAXI/GSC detection
  53. ZTF23aaoohpy/AT2023lcr: SAO RAS observations
  54. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  55. GRB 230622A: Swift detection of a burst
  56. GRB 230621A: Fermi GBM Final Localization Correction
  57. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  58. AT2023lcr: VLA radio detection
  59. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  60. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  61. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  62. IPN triangulation of GRB 230616A (short)
  63. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
  64. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  65. ZTF23aaoohpy/AT2023lcr: OHP/T193 and OHP/T120 optical follow-up observations
  66. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  67. ZTF23aaoohpy/AT2023lcr: GOTO early optical observations and constraint
  68. ZTF23aaoohpy/AT2023lcr: Zwicky Transient Facility discovery of a fast fading red transient
  69. LIGO/Virgo/KAGRA S230615az: GRANDMA observations of GOTO and GIT candidates
  70. GRB 230618A: Enhanced Swift-XRT position
  71. GRB 230618A: Swift/UVOT Upper Limits
  72. GRB 230618A: Swift-XRT refined Analysis
  73. GRB 230616A: Swift-XRT observations
  74. GRB 230618A: KAIT Optical Observations
  75. GRB230618A: LCOGT Optical Observations
  76. GRB 230618B: Fermi GBM Final Real-time Localization
  77. GRB 230618A: Prompt enhanced Swift-XRT position
  78. GRB 230618A: Swift detection of a burst
  79. GRB 230616A: Swift ToO observations
  80. GRB 230617A: Fermi GBM Final Real-time Localization
  81. LIGO/Virgo/KAGRA S230615az: Non-Detections of GROWTH-India Candidates from GECKO Optical Observations
  82. GRB 230614C: GRBAlpha detection
  83. GRB 230616A: AstroSat CZTI detection
  84. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  85. GRB 230614C: AstroSat CZTI detection
  86. GRB 230614C: Fermi GBM Detection
  87. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  88. GRB 230614B: Fermi GBM Final Real-time Localization
  89. GRB 230614A: Fermi GBM Final Real-time Localization
  90. GRB 230606A: LCOGT Optical Observations
  91. GRB 230608A: CALET Gamma-Ray Burst Monitor detection
  92. GRB 230608A: AstroSat CZTI detection
  93. GRB 230608A: AGILE detection
  94. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  95. GRB 230506B: Chandra localization of the X-ray afterglow
  96. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  97. GRB 230606A: Gaoyazi/GOT optical upper limit
  98. GRB 230606A: BOOTES-5/JGT optical upper limit
  99. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  100. GRB 230606A: Swift-XRT refined Analysis

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