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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"

5543 results found.

  1. GRB 240123A: further SAO RAS optical observations
  2. GRB 240123A: SAO RAS optical observations
  3. GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
  4. GRB 240123B: Fermi GBM Final Real-time Localization
  5. GRB 240122A: MAXI/GSC detection
  6. GRB 240115A: Fermi GBM Observation
  7. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  8. Fermi GRB 240115A: Global MASTER-Net observations report
  9. GRB 240115A: Fermi GBM Final Real-time Localization
  10. GRB 240112C: SAO RAS optical observations
  11. GRB 231215A: radio detection with the VLA
  12. GRB 240107A: MAXI/GSC detection
  13. Fermi trigger No 726347794: Global MASTER-Net observations report
  14. GRB 240102C: AstroSat CZTI detection
  15. Fermi trigger No 725806648: Global MASTER-Net observations report
  16. GRB 231222B: GRBAlpha detection
  17. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  18. Fermi trigger No 724781422: Global MASTER-Net observations report
  19. Fermi trigger No 724278269: Global MASTER-Net observations report
  20. IceCube Alert 231211.03: Global MASTER-Net observations report
  21. Fermi trigger No 723581802: Global MASTER-Net observations report
  22. Fermi trigger No 723435916: Global MASTER-Net observations report
  23. Fermi trigger No 723326169: Global MASTER-Net observations report
  24. IceCube-231202A: Upper limits from a search for additional neutrino events in IceCube
  25. Fermi trigger No 723412808: Global MASTER-Net observations report
  26. GRB 231203A: Fermi GBM Observation
  27. GRB 231204A: Fermi GBM Final Real-time Localization
  28. Fermi trigger No 723279695: Global MASTER-Net observations report
  29. GRB 231129B: MAXI/GSC detection
  30. Fermi trigger No 722507896: Global MASTER-Net observations report
  31. Fermi trigger No 722462310: Global MASTER-Net observations report
  32. Fermi trigger No 722400249: Global MASTER-Net observations report
  33. GRB 231117A: CALET Gamma-Ray Burst Monitor detection
  34. LIGO/Virgo/KAGRA S231119ab: Coverage and upper limits from MAXI/GSC observations
  35. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  36. GRB 231117A: GECAM-C detection
  37. GRB 231117A: GRBAlpha detection
  38. GRB 231117A: REM optical and NIR early-time observations
  39. GRB 231117A (short): Glowbug gamma-ray detection
  40. GRB 231117A: ATLAS non-detection of an optical counterpart
  41. Konus-Wind detection of GRB 231117A (short/hard)
  42. GRB 231115A: optical observations from INAF observatories
  43. GRB 231117A: AGILE detection of a bright short burst
  44. GRB 231117A: AstroSat CZTI detection of a bright short burst
  45. GRB 231117A: Swift detection of a bright short burst
  46. GRB231115A: Liverpool Telescope imaging
  47. GRB 231115A: archival HST observations
  48. Fermi GRB 231115A: Global MASTER-Net observations report
  49. GRB 231111A: GMG observation (correction)
  50. GRB 231111A: GMG observation upper limit
  51. LIGO/Virgo/KAGRA S231110g: Identification of a GW compact binary merger candidate
  52. IceCube-231103A: No candidates from the Zwicky Transient Facility
  53. Fermi trigger No 721204446: Global MASTER-Net observations report
  54. Fermi GRB 231108A: Global MASTER-Net observations report
  55. GRB 231108A: Fermi GBM Final Real-time Localization
  56. Fermi GRB 231106A: Global MASTER-Net observations report
  57. IceCube-231103A: Upper limits from a search for additional neutrino events in IceCube
  58. Fermi-LAT gamma-ray observations of IceCube-231103A
  59. Fermi GRB 231103A: Global MASTER-Net observations report
  60. GRB231104A: LCOGT Optical Upper Limits
  61. IceCube Alert 231103.39: Global MASTER-Net observations report
  62. IceCube-231103A - IceCube observation of a high-energy neutrino candidate track-like event
  63. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  64. Fermi trigger No 720498201: Global MASTER-Net observations report
  65. Fermi GRB 231030B: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  67. Fermi trigger No 720224759: Global MASTER-Net observations report
  68. IceCube Alert 231027.18: Global MASTER-Net observations report
  69. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  70. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  71. LIGO/Virgo/KAGRA S231025a: two counterpart neutrino candidates from IceCube neutrino searches
  72. IceCube-231004A: Upper limits from a search for additional neutrino events in IceCube
  73. IceCube-231004A: No significant detection in HAWC
  74. GRB 231003A is not a GRB
  75. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  76. LIGO/Virgo/KAGRA S230922g: Identification of a GW compact binary merger candidate
  77. Fermi GBM Statement for Trigger 716527670/230916144
  78. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  79. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  80. GRB 230911A: Fermi GBM Observation
  81. Swift GRB230916.13: Global MASTER-Net observations report
  82. GRB 230911A: Swift-XRT afterglow detection
  83. Fermi trigger No 716449174: Global MASTER-Net observations report
  84. GRB 230911A: GOTO optical counterpart candidate
  85. IPN triangulation of GRB 230911D (long)
  86. GRB 230911A: Fermi GBM Final Real-time Localization
  87. GRB 230910A: Fermi GBM Final Real-time Localization
  88. LIGO/Virgo/KAGRA S230908b: one counterpart neutrino candidate from IceCube neutrino searches
  89. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  90. Fermi GRB 230906A: Global MASTER-Net observations report
  91. Fermi trigger No 715429986: Global MASTER-Net observations report
  92. Swift GRB230903.72: Global MASTER-Net observations report
  93. Fermi GRB 230827A: Global MASTER-Net observations report
  94. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  95. Fermi trigger No 714618399: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S230824r: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S230822bm: Identification of a GW compact binary merger candidate
  98. GRB 230815A: ATCA detection of radio counterpart
  99. GRB 230818A: Tautenburg observations
  100. GRB 230818A: Bassano Bresciano Observatory optical observations

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