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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"

5173 results found.

  1. GRB 230625A: Fermi GBM Final Real-time Localization
  2. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  3. LIGO/Virgo/KAGRA S230624av: Identification of a GW compact binary merger candidate
  4. GRB 230623A: MAXI/GSC detection
  5. LIGO/Virgo S230622e: Global MASTER-Net observations report
  6. LIGO/Virgo S230621ad: Global MASTER-Net observations report
  7. Fermi trigger No 709083929: Global MASTER-Net observations report
  8. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  9. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  10. LIGO/Virgo S230618ba: Global MASTER-Net observations report
  11. GRB 230618A: Swift-XRT refined Analysis
  12. LIGO/Virgo S230616aa: Global MASTER-Net observations report
  13. LIGO/Virgo S230618d: Global MASTER-Net observations report
  14. LIGO/Virgo S230617bc: Global MASTER-Net observations report
  15. LIGO/Virgo S230617aq: Global MASTER-Net observations report
  16. LIGO/Virgo/KAGRA S230615az: T80S Search and Candidate Counterpart Identification
  17. LIGO/Virgo S230616s: Global MASTER-Net observations report
  18. LIGO/Virgo S230615be: Global MASTER-Net observations report
  19. LIGO/Virgo S230615i: Global MASTER-Net observations report
  20. LIGO/Virgo S230609u: Global MASTER-Net observations report
  21. LIGO/Virgo S230608aw: Global MASTER-Net observations report
  22. LIGO/Virgo S230609a: Global MASTER-Net observations report
  23. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  24. LIGO/Virgo S230608q: Global MASTER-Net observations report
  25. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  26. LIGO/Virgo/KAGRA S230608as: Identification of a GW compact binary merger candidate
  27. Fermi GRB 230603A: Global MASTER-Net observations report
  28. Fermi trigger No 707039690: Global MASTER-Net observations report
  29. GRB 230606A: Swift-XRT refined Analysis
  30. LIGO/Virgo/KAGRA S230606d: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo S230604z: Global MASTER-Net observations report
  32. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  33. LIGO/Virgo S230525a: Global MASTER-Net observations report
  34. Fermi-LAT gamma-ray observations of IceCube-230524A
  35. IceCube-230524A: Upper limits from a search for additional neutrino events in IceCube
  36. GRB 230524A: Fermi GBM Observation
  37. IceCube Alert 230524.47: Global MASTER-Net observations report
  38. IceCube-230524A - IceCube observation of a high-energy neutrino candidate track-like event
  39. GRB 230524B: AstroSat CZTI detection
  40. GRB 230524A: AstroSat CZTI detection
  41. GRB 230524A: AGILE detection
  42. Fermi trigger No 706610076: Global MASTER-Net observations report
  43. LIGO/Virgo S230524b: Global MASTER-Net observations report
  44. GRB 230524A: Fermi GBM Final Real-time Localization
  45. Fermi trigger No 706599831: Global MASTER-Net observations report
  46. Fermi trigger No 706536788: Global MASTER-Net observations report
  47. LIGO/Virgo S230522a: Global MASTER-Net observations report
  48. LIGO/Virgo S230521k: Global MASTER-Net observations report
  49. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  50. Fermi trigger No 706317104: Global MASTER-Net observations report
  51. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  52. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  53. GRB 230520A: MAXI/GSC detection
  54. LIGO/Virgo/KAGRA S230518h: Swope Search and Candidate Counterpart Identification
  55. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  56. LIGO/Virgo S230518h: Global MASTER-Net observations report
  57. GRB 230510A: GRBAlpha detection
  58. Fermi trigger No 705565670: Global MASTER-Net observations report
  59. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  60. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  61. GRB 230510A: Swift-XRT refined Analysis
  62. Fermi trigger No 705413051: Global MASTER-Net observations report
  63. GRB 230506B: Swift-XRT refined Analysis
  64. GRB 230506C: Swift-XRT analysis
  65. GRB 230506C: TSHAO possible afterglow candidate
  66. GRB 230427A: Nanshan/HMT optical upper limit
  67. Fermi trigger No 704365743: Global MASTER-Net observations report
  68. GRB 230427A: MITSuME Akeno optical upper limits
  69. GRB 230426A: Fermi GBM Detection
  70. Fermi trigger No 704233744: Global MASTER-Net observations report
  71. GRB 230426A: Fermi GBM Final Real-time Localization
  72. Konus-Wind detection of GRB 230418A
  73. GRB 230420A: MITSuME Akeno optical observation
  74. GRB 230402A: Fermi GBM detection
  75. GRB 230402A: Fermi-LAT detection
  76. Fermi GRB 230414A: Global MASTER-Net observations report
  77. Fermi GRB 230409A: Global MASTER-Net observations report
  78. GRB 230409B: Swift-XRT refined Analysis
  79. MAXI GRB230408.82: Global MASTER-Net observations report
  80. IceCube Alert 230405.56: Global MASTER-Net observations report
  81. GRB 230307A: further analysis of the Konus-Wind detection and rest-frame energetics
  82. GRB 230328B: Swift/UVOT Detection
  83. Fermi trigger No 701883729: Global MASTER-Net observations report
  84. Konus-Wind detection of GRB 230328B
  85. GRB 230328B: Swift-XRT refined Analysis
  86. GRB 230328B: Mondy optical afterglow confirmation
  87. GRB 230328B: Swift detection of a burst with an optical afterglow
  88. GRB 230328A: Fermi GBM Final Real-time Localization
  89. GRB 230325A: Swift-XRT refined Analysis
  90. Fermi trigger No 701313046: Global MASTER-Net observations report
  91. Fermi trigger No 701321709: Global MASTER-Net observations report
  92. GRB 230322B: Swift-XRT refined Analysis
  93. Fermi trigger No 701071944: Global MASTER-Net observations report
  94. Fermi trigger No 701058254: Global MASTER-Net observations report
  95. GRB 230321B: AstroSat CZTI detection
  96. GRB 230314A: TURBO Optical Upper Limit
  97. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  98. IPN triangulation of GRB 230304B
  99. GRB 230314A: Fermi GBM Final Real-time Localization
  100. Further improved IPN localization for GRB 230307A

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