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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"

36002 results found.

  1. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  2. GRB 230628E - VLT spectroscopic observations
  3. Fermi GRB 230628C: Global MASTER-Net observations report
  4. GRB 230625B: AstroSat CZTI detection
  5. GRB230628E: VLT optical identification of afterglow candidate
  6. GRB 230628E: Swift-XRT refined Analysis
  7. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  8. GRB 230628A: Enhanced Swift-XRT position
  9. Fermi GRB 230628D: Global MASTER-Net observations report
  10. GRB 230628E: LCOGT Optical Upper Limit
  11. GRB 230628E: Swift detection of a burst
  12. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  13. GRB 230628D: Fermi GBM Final Real-time Localization
  14. GRB 230628C: Fermi GBM Final Real-time Localization
  15. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  16. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  17. GRB 230628A: Fermi GBM Final Localization
  18. GRB 230626A: GRBAlpha detection
  19. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  20. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  21. GRB230626A: Fermi GBM Detection
  22. Konus-Wind detection of GRB 230616A
  23. GRB 230618A: Swift-BAT refined analysis
  24. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  25. GRB 230622A: Swift-BAT refined analysis
  26. GRB 230623A: Swift-XRT observations
  27. GRB 230625A: Fermi GBM Final Real-time Localization
  28. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  29. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  30. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  31. GRB 230623A: Tiled Swift observations
  32. MAXI GRB 230623A: MASTER optical observations
  33. GRB 230623A: Tiled Swift observations
  34. GRB 230622A: ATCA rapid radio follow-up
  35. GRB 230622A: Swift-XRT refined Analysis
  36. GRB 230623A: MAXI/GSC detection
  37. Swift GRB 230622A: Global MASTER-Net observations report
  38. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  39. GRB 230622A: Swift detection of a burst
  40. GRB 230621A: Fermi GBM Final Localization Correction
  41. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  42. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  43. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  44. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  45. IPN triangulation of GRB 230616A (short)
  46. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): Kinder observations with Lulin observatory and a probable plateau in the g-band light curve
  47. ZTF23aaoohpy/AT2023lcr: Keck/LRIS spectroscopy and redshift
  48. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  49. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  50. GRB 230618A: Enhanced Swift-XRT position
  51. GRB 230618A: Swift/UVOT Upper Limits
  52. GRB 230618A: Swift-XRT refined Analysis
  53. GRB 230616A: Swift-XRT observations
  54. GRB 230618A: KAIT Optical Observations
  55. Swift GRB 230618A: Global MASTER-Net observations report
  56. GRB230618A: LCOGT Optical Observations
  57. GRB 230618B: Fermi GBM Final Real-time Localization
  58. GRB 230618A: Prompt enhanced Swift-XRT position
  59. GRB 230618A: Swift detection of a burst
  60. GRB 230616A: Swift ToO observations
  61. GRB 230617A: Fermi GBM Final Real-time Localization
  62. GRB 230614C: GRBAlpha detection
  63. GRB 230616A: AstroSat CZTI detection
  64. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  65. GRB 230614C: AstroSat CZTI detection
  66. GRB 230614B: Fermi GBM Observation
  67. GRB 230614C: Fermi GBM Detection
  68. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  69. GRB 230614B: Fermi GBM Final Real-time Localization
  70. GRB 230614A: Fermi GBM Final Real-time Localization
  71. GRB 230606A: LCOGT Optical Observations
  72. GRB 230608A: CALET Gamma-Ray Burst Monitor detection
  73. GRB 230608A: AstroSat CZTI detection
  74. GRB 230608A: AGILE detection
  75. Fermi GRB 230603A: Global MASTER-Net observations report
  76. GRB 230506B: Chandra localization of the X-ray afterglow
  77. GRB 230606A: Swift-BAT refined analysis
  78. GRB 230606A: Gaoyazi/GOT optical upper limit
  79. GRB 230606A: Fermi GBM Observation
  80. GRB 230606A: BOOTES-5/JGT optical upper limit
  81. GRB 230606A: Swift-XRT refined Analysis
  82. GRB 230604A: GRBAlpha detection
  83. GRB 230606A: Swift/UVOT Upper Limits
  84. GRB 230606A: Enhanced Swift-XRT position
  85. GRB 230606A: Swift detection of a burst
  86. GRB 230604A: AstroSat CZTI detection of a short GRB
  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: Upper limits from Fermi-GBM Observations
  92. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  93. GRB 230529A: Fermi GBM Final Real-time Localization
  94. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  95. GRB 230510A: Swift-BAT refined analysis
  96. GRB 230525A: Fermi GBM Detection
  97. GRB 230525A: Fermi GBM Final Localization
  98. GRB 230523B: GRBAlpha detection
  99. GRB 230524A: Fermi GBM Observation
  100. GRB 230524B: AstroSat CZTI detection

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