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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"

36384 results found.

  1. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  2. Fermi GRB 230707A: Global MASTER-Net observations report
  3. GRB 230707A: Fermi GBM Final Real-time Localization
  4. IBAS trigger number 10311: not a real GRB
  5. GRB 230625A: Detection by GRID
  6. LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
  7. GRB 230626A: VZLUSAT-2 detection
  8. LVK S230619bd/GBM-230619: Upper limits from a two-week IceCube neutrino search
  9. GRB 230328B: LBT detection of the likely host galaxy
  10. Konus-Wind detection of GRB 220623A
  11. GRB 230701B: AstroSat CZTI detection
  12. GRB 230628E: Swift/UVOT Detection
  13. GRB 230628E: Swift-BAT refined analysis
  14. GRB 230702A: Fermi GBM Final Real-time Localization
  15. GRB 230628E: ATCA rapid radio follow-up
  16. GRB 230701A: Fermi GBM Final Real-time Localization
  17. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  18. IPN triangulation of GRB 230625B (ultra-long)
  19. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  20. GRB 230628E - VLT spectroscopic observations
  21. Fermi GRB 230628C: Global MASTER-Net observations report
  22. GRB 230625B: AstroSat CZTI detection
  23. GRB230628E: VLT optical identification of afterglow candidate
  24. GRB 230628E: Swift-XRT refined Analysis
  25. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  26. GRB 230628A: Enhanced Swift-XRT position
  27. Fermi GRB 230628D: Global MASTER-Net observations report
  28. GRB 230628E: LCOGT Optical Upper Limit
  29. GRB 230628E: Swift detection of a burst
  30. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  31. GRB 230628D: Fermi GBM Final Real-time Localization
  32. GRB 230628C: Fermi GBM Final Real-time Localization
  33. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  34. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  35. GRB 230628A: Fermi GBM Final Localization
  36. GRB 230626A: GRBAlpha detection
  37. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  38. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  39. GRB230626A: Fermi GBM Detection
  40. Konus-Wind detection of GRB 230616A
  41. GRB 230618A: Swift-BAT refined analysis
  42. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  43. GRB 230622A: Swift-BAT refined analysis
  44. GRB 230623A: Swift-XRT observations
  45. GRB 230625A: Fermi GBM Final Real-time Localization
  46. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  47. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  48. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  49. GRB 230623A: Tiled Swift observations
  50. MAXI GRB 230623A: MASTER optical observations
  51. GRB 230623A: Tiled Swift observations
  52. GRB 230622A: ATCA rapid radio follow-up
  53. GRB 230622A: Swift-XRT refined Analysis
  54. GRB 230623A: MAXI/GSC detection
  55. Swift GRB 230622A: Global MASTER-Net observations report
  56. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  57. GRB 230622A: Swift detection of a burst
  58. GRB 230621A: Fermi GBM Final Localization Correction
  59. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  60. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  61. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  62. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  63. IPN triangulation of GRB 230616A (short)
  64. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): Kinder observations with Lulin observatory and a probable plateau in the g-band light curve
  65. ZTF23aaoohpy/AT2023lcr: Keck/LRIS spectroscopy and redshift
  66. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  67. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  68. GRB 230618A: Enhanced Swift-XRT position
  69. GRB 230618A: Swift/UVOT Upper Limits
  70. GRB 230618A: Swift-XRT refined Analysis
  71. GRB 230616A: Swift-XRT observations
  72. GRB 230618A: KAIT Optical Observations
  73. Swift GRB 230618A: Global MASTER-Net observations report
  74. GRB230618A: LCOGT Optical Observations
  75. GRB 230618B: Fermi GBM Final Real-time Localization
  76. GRB 230618A: Prompt enhanced Swift-XRT position
  77. GRB 230618A: Swift detection of a burst
  78. GRB 230616A: Swift ToO observations
  79. GRB 230617A: Fermi GBM Final Real-time Localization
  80. GRB 230614C: GRBAlpha detection
  81. GRB 230616A: AstroSat CZTI detection
  82. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  83. GRB 230614C: AstroSat CZTI detection
  84. GRB 230614B: Fermi GBM Observation
  85. GRB 230614C: Fermi GBM Detection
  86. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  87. GRB 230614B: Fermi GBM Final Real-time Localization
  88. GRB 230614A: Fermi GBM Final Real-time Localization
  89. GRB 230606A: LCOGT Optical Observations
  90. GRB 230608A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 230608A: AstroSat CZTI detection
  92. GRB 230608A: AGILE detection
  93. Fermi GRB 230603A: Global MASTER-Net observations report
  94. GRB 230506B: Chandra localization of the X-ray afterglow
  95. GRB 230606A: Swift-BAT refined analysis
  96. GRB 230606A: Gaoyazi/GOT optical upper limit
  97. GRB 230606A: Fermi GBM Observation
  98. GRB 230606A: BOOTES-5/JGT optical upper limit
  99. GRB 230606A: Swift-XRT refined Analysis
  100. GRB 230604A: GRBAlpha detection

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