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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"

5546 results found.

  1. GRB 230815A: ATCA detection of radio counterpart
  2. GRB 230818A: Tautenburg observations
  3. GRB 230818A: Bassano Bresciano Observatory optical observations
  4. GRB 230818A: KGO RC-25 optical observations
  5. GRB 230818A: Swift/UVOT Detection
  6. GRB 230818A: SAO RAS Zeiss-1000 observations
  7. Fermi GRB 230818A: Global MASTER-Net observations report
  8. GRB 230817A: AstroSat CZTI detection
  9. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  10. GRB 230815A: SOAR/Goodman follow-up imaging
  11. GRB 230815A: Swift-BAT refined analysis
  12. GRB 230815A: Enhanced Swift-XRT position
  13. GRB 230815A: Swift detection of a burst
  14. GRB 230812B: further SAO RAS optical observations
  15. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  16. LAT GRB230812.79: Global MASTER-Net observations report
  17. Fermi GRB 230812B: Global MASTER-Net observations report
  18. LIGO/Virgo/KAGRA S230811n: Identification of a GW compact binary merger candidate
  19. Fermi trigger No 713136868: Global MASTER-Net observations report
  20. Fermi trigger No 713205976: Global MASTER-Net observations report
  21. LIGO/Virgo/KAGRA S230808i: Identification of a GW unmodeled transient candidate
  22. Fermi trigger No 712927418: Global MASTER-Net observations report
  23. LIGO/Virgo/KAGRA S230805x: Identification of a GW compact binary merger candidate
  24. Fermi trigger No 712798043: Global MASTER-Net observations report
  25. GRB 230803A: AstroSat CZTI detection
  26. Fermi trigger No 712718833: Global MASTER-Net observations report
  27. Fermi trigger No 712713532: Global MASTER-Net observations report
  28. Fermi trigger No 712651827: Global MASTER-Net observations report
  29. Swift GRB 230802A: Global MASTER-Net observations report
  30. LIGO/Virgo/KAGRA S230731an: Coverage and upper limits from MAXI/GSC observations
  31. GRB 230728A: LCOGT Optical Upper Limit
  32. GRB 230727A: AstroSat CZTI detection
  33. GRB 230728A: Swift detection of a burst
  34. GRB 230727A: Swift/BAT-GUANO detection of a burst
  35. GRB 230727A: Fermi GBM Final Real-time Localization
  36. IBAS trigger number 10337: not a real GRB
  37. IPN triangulation of GRB 230723A (short)
  38. IceCube Alert 230724.08: Global MASTER-Net observations report
  39. Fermi trigger No 711805358: Global MASTER-Net observations report
  40. GRB 230703A detected with multiple GRID detectors
  41. GRB 230707A: Fermi GBM Detection
  42. Fermi GRB 230707A: Global MASTER-Net observations report
  43. GRB 230707A: Fermi GBM Final Real-time Localization
  44. LVK S230619bd/GBM-230619: Upper limits from a two-week IceCube neutrino search
  45. LIGO/Virgo/KAGRA S230627c: GRANDMA observations of galaxies and ZTF counterpart candidates
  46. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): ALMA 100 GHz Detection
  47. ZTF23aaoohpy /AT2023lcr: TNG NIR detection
  48. LIGO/Virgo/Kagra S230627c: NED Galaxies in the Localization Volume
  49. LIGO/Virgo/KAGRA S230627c: Coverage and upper limits from MAXI/GSC observations
  50. LIGO/Virgo S230622e: Global MASTER-Net observations report
  51. LIGO/Virgo S230621bq: Global MASTER-Net observations report
  52. LIGO/Virgo S230621ad: Global MASTER-Net observations report
  53. LIGO/Virgo S230620ad: Global MASTER-Net observations report
  54. LIGO/Virgo S230620au: Global MASTER-Net observations report
  55. LIGO/Virgo S230620z: Global MASTER-Net observations report
  56. LIGO/Virgo S230620w: Global MASTER-Net observations report
  57. LIGO/Virgo S230619bg: Global MASTER-Net observations report
  58. LIGO/Virgo S230618s: Global MASTER-Net observations report
  59. GRB 230618A: Swift-XRT refined Analysis
  60. LIGO/Virgo S230616aa: Global MASTER-Net observations report
  61. LIGO/Virgo S230615ak: Global MASTER-Net observations report
  62. LIGO/Virgo S230618k: Global MASTER-Net observations report
  63. LIGO/Virgo S230618d: Global MASTER-Net observations report
  64. LIGO/Virgo S230617bc: Global MASTER-Net observations report
  65. LIGO/Virgo S230617aq: Global MASTER-Net observations report
  66. LIGO/Virgo S230617ab: Global MASTER-Net observations report
  67. Swift GRB 230618A: Global MASTER-Net observations report
  68. LIGO/Virgo S230617aj: Global MASTER-Net observations report
  69. GRB230618A: LCOGT Optical Observations
  70. GRB 230618A: Prompt enhanced Swift-XRT position
  71. GRB 230618A: Swift detection of a burst
  72. LIGO/Virgo/KAGRA S230615az: Non-Detections of GROWTH-India Candidates from GECKO Optical Observations
  73. LIGO/Virgo S230615be: Global MASTER-Net observations report
  74. LIGO/Virgo/KAGRA S230615az: GROWTH-India candidates
  75. GRB 230606A: LCOGT Optical Observations
  76. LIGO/Virgo S230608aw: Global MASTER-Net observations report
  77. LIGO/Virgo S230609a: Global MASTER-Net observations report
  78. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  79. LIGO/Virgo S230608q: Global MASTER-Net observations report
  80. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  81. Fermi trigger No 707039690: Global MASTER-Net observations report
  82. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  83. LIGO/Virgo S230606d: Global MASTER-Net observations report
  84. Fermi-LAT gamma-ray observations of IceCube-230603A
  85. IceCube-230603A: Upper limits from a search for additional neutrino events in IceCube
  86. IceCube-230603A - IceCube observation of a high-energy neutrino candidate track-like event
  87. LIGO/Virgo S230603aa: Global MASTER-Net observations report
  88. LIGO/Virgo S230602ap: Global MASTER-Net observations report
  89. GRB 230522A: GRBAlpha and VZLUSAT-2 joint detection
  90. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  91. LIGO/Virgo S230525a: Global MASTER-Net observations report
  92. Fermi trigger No 706610076: Global MASTER-Net observations report
  93. Fermi Gamma-ray Burst Monitor trigger 706536788/230523509 is not a GRB
  94. LIGO/Virgo S230522a: Global MASTER-Net observations report
  95. LIGO/Virgo S230521k: Global MASTER-Net observations report
  96. Fermi Gamma-ray Burst Monitor trigger 706338208/230521211 is not a GRB
  97. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  98. Fermi trigger No 706331483: Global MASTER-Net observations report
  99. Fermi trigger No 706317104: Global MASTER-Net observations report
  100. GRB 230520A: CALET Gamma-Ray Burst Monitor detection

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