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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').

276 results found.

  1. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  2. IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
  3. IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
  5. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  6. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  7. IceCube-240123A: Upper limits from a search for additional neutrino events in IceCube
  8. GRB 240106A: Glowbug gamma-ray detection
  9. IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
  10. IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
  11. LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
  12. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  13. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  14. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  15. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  16. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  17. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. IceCube-Cascade 230610A: Upper limits from a search for additional neutrino events in IceCube
  19. LIGO/Virgo/KAGRA S230609u: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  21. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  22. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  23. IceCube-Cascade 230511A: Upper limits from a search for additional neutrino events in IceCube
  24. IceCube-Cascade 230430A: Upper limits from a search for additional neutrino events in IceCube
  25. IceCube-230416A: Upper limits from a search for additional neutrino events in IceCube
  26. IceCube-230405A: Upper limits from a search for additional neutrino events in IceCube
  27. INTEGRAL detection of a burst from SGR 1806-200
  28. GRB 230307A: soft X-ray detection with LEIA
  29. GRB 230307A: GECAM detection of an extremely bright burst
  30. IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
  31. IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube
  32. IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube
  33. Fermi-LAT gamma-ray observations of IceCube-230112A
  34. IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube
  35. Fermi-LAT gamma-ray observations of IceCube-221223A
  36. IceCube-221216A: Upper limits from a search for additional neutrino events in IceCube
  37. IceCube-221124A: Upper limits from a search for additional neutrino events in IceCube
  38. IceCube-221104A: Upper limits from a search for additional neutrino events in IceCube
  39. Konus-Wind observation of the recent SGR 1935+2154 activity
  40. INTEGRAL detection of a burst from SGR J1935+2154
  41. IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
  42. IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
  43. IceCube-220629A: Upper limits from a search for additional neutrino events in IceCube
  44. IceCube-220627A: Upper limits from a search for additional neutrino events in IceCube
  45. IceCube-Cascade 220625A: Upper limits from a search for additional neutrino events in IceCube
  46. IceCube-220509A: Upper limits from a search for additional neutrino events in IceCube
  47. IceCube-220425A: Upper limits from a search for additional neutrino events in IceCube
  48. IceCube-220424A: Upper limits from a search for additional neutrino events in IceCube
  49. IceCube-220421A: Upper limits from a search for additional neutrino events in IceCube
  50. IceCube-220317A: Upper limits from a search for additional neutrino events in IceCube
  51. IceCube-220306A: Upper limits from a search for additional neutrino events in IceCube
  52. IceCube-220303A: Upper limits from a search for additional neutrino events in IceCube
  53. GRB 220228A: Fermi-LAT detection
  54. GRB 220101A: The first example of a Petanova
  55. IceCube-220205A: Upper limits from a search for additional neutrino events in IceCube
  56. IceCube-211216A: Upper limits from a search for additional neutrino events in IceCube
  57. IceCube-211216A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  58. IceCube-211208A: Upper limits from a search for additional neutrino events in IceCube
  59. IceCube-211208A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  60. IceCube-Cascade 211128A: Upper limits from a search for additional neutrino events in IceCube
  61. IceCube-211125A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  62. IceCube-211123A: Upper limits from a search for additional neutrino events in IceCube
  63. HAWC-211123A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  64. Konus-Wind observation of the recent SGR 1935+2154 activity
  65. IceCube-210730A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  66. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  67. INTEGRAL detection of a burst from SGR 1935+2154
  68. IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  69. IceCube-210510A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  70. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  71. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  72. GRB 210402A: MASTER prompt and follow up optical observation
  73. Fermi-LAT Gamma-ray Observations of IceCube-210210A
  74. IceCube-210210A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  75. Konus-Wind detection of two bright bursts from SGR 1935+2154
  76. NuEm-210111A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  77. IceCube-201222A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  78. IceCube-201221A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  79. IceCube-201209A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  80. IceCube-201130A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  81. IceCube-201120A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  82. IceCube-201115A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  83. IceCube-201114A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  84. VLASS identifies possible radio counterparts to IceCube-201115A, including a bright BL Lac candidate
  85. IceCube-201021A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  86. IceCube-201014A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  87. IceCube-201007A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  88. IceCube-200926B: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  89. IceCube-200929A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  90. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  91. IceCube-200921A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  92. IceCube-200916A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  93. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  94. IceCube-200911A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  95. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  96. Fermi-LAT Gamma-ray Observations of IceCube-200806A
  97. IceCube-200615A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  98. IceCube-200614A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  99. Fermi-LAT Gamma-ray Observations of IceCube-200530A
  100. IceCube-200530A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation

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