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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

2983 results found.

  1. Fermi GRB 230723A: Global MASTER-Net observations report
  2. IPN triangulation of GRB 230715D
  3. GRB 230709C: Fermi GBM Final Localization
  4. IceCube Alert 230707.71: Global MASTER-Net observations report
  5. LIGO/Virgo/KAGRA S230707ai: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230701z: one counterpart neutrino candidate from IceCube neutrino searches
  7. IPN triangulation of GRB 230625B (ultra-long)
  8. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  9. GRB 230625B: AstroSat CZTI detection
  10. Fermi GRB 230628D: Global MASTER-Net observations report
  11. LIGO/Virgo/KAGRA S230628ax: Identification of a GW compact binary merger candidate
  12. GRB 230628E: LCOGT Optical Upper Limit
  13. Swift GRB230628.93: Global MASTER-Net observations report
  14. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  15. GRB 230628D: Fermi GBM Final Real-time Localization
  16. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230628aj: one counterpart neutrino candidate from IceCube neutrino searches
  17. GRB 230628C: Fermi GBM Final Real-time Localization
  18. GRB 230628A: Fermi GBM Final Localization
  19. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  20. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  21. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  22. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  23. LIGO/Virgo S230620ad: Global MASTER-Net observations report
  24. LIGO/Virgo S230620au: Global MASTER-Net observations report
  25. LIGO/Virgo S230620al: Global MASTER-Net observations report
  26. LIGO/Virgo S230619bg: Global MASTER-Net observations report
  27. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  28. LIGO/Virgo S230618y: Global MASTER-Net observations report
  29. LIGO/Virgo S230618r: Global MASTER-Net observations report
  30. LIGO/Virgo S230616aa: Global MASTER-Net observations report
  31. LIGO/Virgo S230618k: Global MASTER-Net observations report
  32. LIGO/Virgo S230617aj: Global MASTER-Net observations report
  33. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  34. Fermi GRB 230603A: Global MASTER-Net observations report
  35. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  36. LIGO/Virgo S230525a: Global MASTER-Net observations report
  37. LIGO/Virgo/KAGRA S230518h: No transient candidates in CALET observations
  38. Fermi trigger No 706536788: Global MASTER-Net observations report
  39. LIGO/Virgo S230522a: Global MASTER-Net observations report
  40. LIGO/Virgo S230521k: Global MASTER-Net observations report
  41. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  42. IPN triangulation of GRB 230518A (short)
  43. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  44. GRB 230520A: MAXI/GSC detection
  45. LIGO/Virgo S230518h: Global MASTER-Net observations report
  46. GRB 230510B: Fermi GBM detection
  47. GRB 230512A: Kitab possible afterglow candidate
  48. GRB 230512A: Swift-XRT observations
  49. GRB 230512A: GIT optical follow-up ZTF candidates
  50. GRB 230511C: Fermi GBM Final Localization
  51. GRB 230510B: MAXI/GSC detection
  52. Fermi trigger No 705413051: Global MASTER-Net observations report
  53. GRB 230510A: Swift detection of a burst
  54. GRB 230506C: Swift-BAT refined analysis
  55. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  56. Fermi trigger No 704365743: Global MASTER-Net observations report
  57. GRB 230428A: Fermi GBM Final Real-time Localization
  58. GRB 230427A: GMG upper limit
  59. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  60. GRB 230426A: Fermi GBM Detection
  61. GRB 230426A: Fermi GBM Final Real-time Localization
  62. GRB 230420A: MITSuME Akeno optical observation
  63. GRB 230420A: LCOGT Optical Upper Limit
  64. IPN triangulation of GRB 230418A (short)
  65. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  66. Fermi GRB 230414A: Global MASTER-Net observations report
  67. Fermi trigger No 702745263: Global MASTER-Net observations report
  68. IceCube-230405A: Upper limits from a search for additional neutrino events in IceCube
  69. GRB 230307A: short mininum variability timescale compatible with a merger origin
  70. GRB 230328B: Multa observatory optical afterglow observation
  71. Fermi GRB 230402A: Global MASTER-Net observations report
  72. IceCube-Cascade 230329A: Upper limits from a search for additional neutrino events in IceCube
  73. GRB 230328B: 3.6m DOT multiband optical observation
  74. GRB 230328B: GRBAlpha detection
  75. GRB 230328B NUTTelA-TAO / BSTI Early Measurements
  76. GRB 230328B: OHP/T120 optical observations
  77. GRB 230328B: GIT optical follow-up
  78. GRB 230328B: Nanshan/NEXT optical upper limit
  79. GRB 230328B: AstroSat CZTI detection
  80. GRB 230328B: Fermi GBM observation
  81. GRB 230328B: Mondy, AbAO and Kitab optical observations
  82. GRB 230328B: Mondy optical afterglow confirmation
  83. GRB 230328B: Fermi GBM Final Real-time Localization
  84. Fermi GRB 230328A: Global MASTER-Net observations report
  85. GRB 230328A: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 701313046: Global MASTER-Net observations report
  87. Konus-Wind detection of GRB 230304B
  88. Fermi trigger No 701071944: Global MASTER-Net observations report
  89. GRB 230314A: TURBO Optical Upper Limit
  90. Fermi GRB 230314A: Global MASTER-Net observations report
  91. Further improved IPN localization for GRB 230307A
  92. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  93. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  94. Fermi GRB 230307A: Global MASTER-Net observations report
  95. Konus-Wind detection of GRB 230307A
  96. GRB 230228A: VIRT Optical Upper Limit
  97. GRB 230307A: VZLUSAT-2 detection
  98. GRB 230304B: Detection by GRBAlpha
  99. GRB 230301B: Fermi GBM Final Real-time Localization
  100. GRB 230228A: Fermi GBM Observation

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