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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"

32550 results found.

  1. IPN triangulation of GRB 230511D (short)
  2. IPN triangulation of GRB 230512A
  3. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  4. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  5. GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate
  6. GRB 230512A: Liverpool Telescope observations
  7. GRB 230512A: GIT non detection of afterglow candidate
  8. GRB 230512A: Kitab possible afterglow candidate
  9. GRB 230512A: GRBAlpha detection
  10. GRB 230510A: GRBAlpha detection
  11. Fermi-LAT gamma-ray observations of IceCube-230511A
  12. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  13. IceCube-230511A: Upper limits from a search for additional neutrino events in IceCube
  14. GRB 230512A: GIT optical follow-up ZTF candidates
  15. GRB 230512A: Fermi GBM detection
  16. GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670)
  17. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  18. GRB 230512A: Tiled Swift observations
  19. GRB 230512A: Fermi-LAT detection
  20. GRB 230512A: AstroSat CZTI detection
  21. GRB 230510A: GIT optical upper limits
  22. GRB 230510A: LCOGT Optical Upper Limit
  23. GRB 230510A: Swift/UVOT Observations
  24. GRB 230510B: AstroSat CZTI detection
  25. GRB 230510A: Fermi GBM detection
  26. GRB 230510A: Gaoyazi/GOT optical upper limit
  27. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  28. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  29. GRB 230510A: Nanshan/NEXT optical afterglow detection
  30. GRB 230510B: MAXI/GSC detection
  31. GRB 230506B: Fermi GBM detection
  32. GRB 230506C: Fermi GBM detection
  33. GRB 230506C: T193-OHP MISTRAL tentative redshift
  34. GRB 230506C: SAO RAS optical observations
  35. GRB 230307A: JWST second-epoch observations
  36. IceCube-230506A: Upper limits from a search for additional neutrino events in IceCube
  37. Fermi-LAT gamma-ray observations of IceCube-230506A
  38. GRB 230506C: Swift-BAT refined analysis
  39. GRB 230506B: Swift-BAT refined analysis
  40. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  41. GRB 230506B: LCOGT Optical Upper Limits
  42. GRB 230506C: Swift/UVOT Upper Limits
  43. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  44. GRB 230506C: TSHAO possible afterglow candidate
  45. GRB 230506B: Swift/UVOT Detection
  46. GRB 230506B: Swift detection of a burst
  47. GRB 230506B: MASTER optical observations
  48. GRB 230506B: Swift detection of a burst
  49. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  50. GRB 230427A: Swift-BAT refined analysis
  51. Konus-Wind detection of GRB 230430A
  52. IPN triangulation of GRB 230430A (short)
  53. GRB 230420A: AROMA-N Optical Upper Limit
  54. GRB 230430A: Fermi GBM observation
  55. GRB 230430A: AstroSat CZTI detection
  56. GRB 230427A: NOT optical upper limit
  57. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  58. GRB 230427A: Swift/UVOT Detection
  59. Duplicate of GCN 33369
  60. GRB 230427A: Gaoyazi/GOT optical upper limit
  61. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  62. GRB 230427A: Nanshan/HMT optical upper limit
  63. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  64. GRB 230427A: OSIRIS+/GTC observations
  65. GRB 230426A: VZLUSAT-2 detection
  66. GRB 230427A: GIT optical upper limit
  67. GRB 230427A: Bassano Bresciano Observatory upper limit
  68. GRB 230427A: GMG upper limit
  69. GRB 230427A : OHP/T193 optical upper limit
  70. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  71. GRB 230427A: AKO Upper Limit
  72. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  73. GRB 230427A: MITSuME Akeno optical upper limits
  74. GRB 230426A: Fermi GBM Detection
  75. GRB 230426A: AstroSat CZTI detection
  76. GRB 230423A: Swift/UVOT Upper Limits
  77. GRB 230420A: Lowell Discovery Telescope Optical Detection
  78. GRB 230423A: Swift-XRT afterglow detection
  79. Erroneous submission
  80. GRB 221009A: Late-time JWST Observations and Detection of Supernova Emission
  81. GRB 230421A: Fermi GBM observation
  82. Konus-Wind detection of GRB 230418A
  83. GRB 230420A: Swift/UVOT Upper Limits
  84. GRB 230421: Swift/BAT-GUANO arcminute localization
  85. GRB230420A: VLT optical observation
  86. GRB 230420A: Swift-BAT refined analysis
  87. Duplicate of GCN 33668
  88. GRB 230420A: MITSuME Akeno optical observation
  89. GRB 230420A: NOT optical afterglow confirmation
  90. GRB 230420A: Gaoyazi/GOT optical upper limit
  91. GRB 230420A: LCOGT Optical Upper Limit
  92. GRB230414B: VIRT Optical Upper Limit
  93. IPN triangulation of GRB 230418A (short)
  94. GRB 230418A: AstroSat CZTI detection
  95. GRB 230402A: Fermi GBM detection
  96. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  97. GRB 230402A: Fermi-LAT detection
  98. Fermi-LAT gamma-ray observations of IceCube-230416A
  99. GRB 230414B: Nickel and KAIT telescope optical observations
  100. Duplicate of GCN 33640

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