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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').

453 results found.

  1. The EP-WXT trigger 01709135179: Kinder optical counterpart candidate
  2. Fermi trigger No 766173972: Global MASTER-Net observations report
  3. EP250402a: Optical upper limit with Kinder observations
  4. GRB 250403A: SVOM/C-GFT optical observations
  5. GRB 250331D: Swift-XRT observations
  6. EP-WXT trigger 01709133021: Optical upper limit through Kinder observations
  7. GRB 250317C: AstroSat CZTI detection
  8. Fermi GRB 250226A: Global MASTER-Net observations report
  9. GRB 250217C: Fermi GBM Observation
  10. GRB 250211A: SVOM trigger sb25021103 is not a GRB
  11. GRB 250206A: Swift-XRT observations
  12. LIGO/Virgo/KAGRA S250206dm: Identification of a GW compact binary merger candidate
  13. Konus-Wind detection of GRB 250117A
  14. Konus-Wind detection of GRB 241204A (short/hard)
  15. GRB 241209D: AstroSat CZTI detection
  16. GRB 241201A: AstroSat CZTI detection
  17. GRB 241117A: Fermi GBM Detection
  18. Fermi trigger No 752878030: Global MASTER-Net observations report
  19. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  20. GRB 241104A: Fermi GBM Observation
  21. Fermi GRB 241104A: Global MASTER-Net observations report
  22. GRB 240912A: radio detection with the VLA
  23. Fermi trigger No 751861204: Global MASTER-Net observations report
  24. Fermi trigger No 750211959: Global MASTER-Net observations report
  25. EP240913A / GRB 240913C: AstroSat CZTI detection
  26. Fermi trigger No 746587425: Global MASTER-Net observations report
  27. LAT GRB240828.62: Global MASTER-Net observations report
  28. GRB 240801B: AstroSat CZTI detection of a bright long burst
  29. Konus-Wind detection of GRB 240718A
  30. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  31. Fermi trigger No 741211696: Global MASTER-Net observations report
  32. Fermi trigger No 739632045: Global MASTER-Net observations report
  33. Konus-Wind detection of GRB 240606B
  34. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  35. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  36. MAXI GRB240514.78: Global MASTER-Net observations report
  37. GRB 240502C: GOTO possible optical counterpart candidates
  38. Fermi GRB 240502A: Global MASTER-Net observations report
  39. GRB240430A: Fermi GBM Final Localization
  40. IceCube Alert 240424.08: Global MASTER-Net observations report
  41. Swift Trigger 1220736: detection of 4U 1543-62.
  42. GRB 240403A: Fermi GBM Detection
  43. Fermi trigger No 733097506: Global MASTER-Net observations report
  44. GRB 231215A: further radio observations with the VLA
  45. Konus-Wind detection of GRB 240205B (long / very soft)
  46. IPN triangulation of GRB 240119A (short)
  47. Swift GRB240109.17: Global MASTER-Net observations report
  48. Fermi trigger No 724698747: Global MASTER-Net observations report
  49. IPN triangulation of GRB 231205A
  50. Fermi GRB 231103A: Global MASTER-Net observations report
  51. GRB 231104A: Swift-XRT refined Analysis
  52. GRB 230808A: Fermi GBM Detection
  53. LIGO/Virgo/KAGRA S230802aq: Updated Sky localization and EM Bright Classification
  54. Fermi trigger No 712713532: Global MASTER-Net observations report
  55. LIGO/Virgo/KAGRA S230802aq: Coverage and upper limits from MAXI/GSC observations
  56. LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
  57. LIGO/Virgo S230621bq: Global MASTER-Net observations report
  58. LIGO/Virgo S230621ad: Global MASTER-Net observations report
  59. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  60. LIGO/Virgo S230620al: Global MASTER-Net observations report
  61. LIGO/Virgo S230620g: Global MASTER-Net observations report
  62. LIGO/Virgo S230604z: Global MASTER-Net observations report
  63. LIGO/Virgo/KAGRA S230529ay: Identification of a GW compact binary merger candidate
  64. IceCube Alert 230524.47: Global MASTER-Net observations report
  65. Fermi trigger No 705503315: Global MASTER-Net observations report
  66. GRB 230307A: JWST second-epoch observations
  67. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  68. TESS Detection of the Optical Afterglow of GRB230307A
  69. Konus-Wind detection of GRB 230307A
  70. GRB 221120A: Fermi GBM observation
  71. GRB 221120A: GIT upper limits on optical afterglow
  72. GRB 221025A: AstroSat CZTI detection
  73. Fermi trigger No 687345829: Global MASTER-Net observations report
  74. Fermi trigger No 687344475: Global MASTER-Net observations report
  75. Integral GRB221013.04: Global MASTER-Net observations report
  76. Fermi trigger No 687014224: Global MASTER-Net observations report
  77. Fermi trigger No 681998863: Global MASTER-Net observations report
  78. Fermi GRB 220610A: Global MASTER-Net observations report
  79. Konus-Wind detection of GRB 220601A
  80. GRB 220521A: classification and detection by SPI-ACS/INTEGRAL
  81. GRB 220430A: AstroSat CZTI detection
  82. GRB 220427A: Swift-BAT refined analysis
  83. GRB 220421B: Detection by VZLUSAT-2
  84. IPN triangulation of GRB 220403C
  85. Fermi GRB 220411A: Global MASTER-Net observations report
  86. GRB 220319A: MASTER Global Robotic Net optical observations
  87. Fermi trigger No 663899819: Global MASTER-Net observations report
  88. Fermi trigger No 663710289: Global MASTER-Net observations report
  89. Swift GRB211227.98: Global MASTER-Net observations report
  90. Fermi GRB 211216B: Global MASTER-Net observations report
  91. Fermi GRB 211211B: Global MASTER-Net observations report
  92. GRB 211207A: Swift-BAT refined analysis
  93. Fermi GRB 211204A: Global MASTER-Net observations report
  94. GRB 211129A: Swift-XRT refined Analysis
  95. GRB 211120548: Fermi GBM observation
  96. GRB 211120A: AGILE detection
  97. Swift GRB211010.45: Global MASTER-Net observations report
  98. Fermi trigger No 655401471: Global MASTER-Net observations report
  99. Fermi trigger No 652911693: Global MASTER-Net observations report
  100. Fermi trigger No 652906639: Global MASTER-Net observations report

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