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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').
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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

308 results found.

  1. IceCube-250416A: Upper limits from a search for additional neutrino events in IceCube
  2. IceCube-250330A: Upper limits from a search for additional neutrino events in IceCube
  3. IceCube-250309A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube-250302A: Upper limits from a search for additional neutrino events in IceCube
  5. IceCube-Cascade 250215A: Upper limits from a search for additional neutrino events in IceCube
  6. LIGO/Virgo/KAGRA S250206dm: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  7. IceCube-250102A: Upper limits from a search for additional neutrino events in IceCube
  8. Fermi GRB 241209A: Global MASTER-Net observations report
  9. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  10. GRB 241130A: EIRSAT-1 GMOD Detection
  11. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  12. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  13. EP241113a: Swift XRT weak detection
  14. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  15. SVOM/GRM detection of a short burst from SGR 1E1841-045
  16. INTEGRAL detection of a burst from 1E 1841-045
  17. EP241107a: EP on-board trigger and autonomous follow-up observation
  18. EP241025a (GRB 241025A): EP observations update
  19. GRB241017A: TOO Observations by SVOM/MXT
  20. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  21. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  22. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  23. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  24. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  25. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  26. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  27. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  28. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  29. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  30. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  31. Fermi trigger No 738348224: Global MASTER-Net observations report
  32. IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
  33. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  34. IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
  35. IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
  36. IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
  37. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  38. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  39. IceCube-240123A: Upper limits from a search for additional neutrino events in IceCube
  40. GRB 240106A: Glowbug gamma-ray detection
  41. IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
  42. IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
  43. LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
  44. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  45. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  46. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  47. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  48. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  49. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  50. IceCube-Cascade 230610A: Upper limits from a search for additional neutrino events in IceCube
  51. LIGO/Virgo/KAGRA S230609u: Identification of a GW compact binary merger candidate
  52. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  53. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  54. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  55. IceCube-Cascade 230511A: Upper limits from a search for additional neutrino events in IceCube
  56. IceCube-Cascade 230430A: Upper limits from a search for additional neutrino events in IceCube
  57. IceCube-230416A: Upper limits from a search for additional neutrino events in IceCube
  58. IceCube-230405A: Upper limits from a search for additional neutrino events in IceCube
  59. INTEGRAL detection of a burst from SGR 1806-200
  60. GRB 230307A: soft X-ray detection with LEIA
  61. GRB 230307A: GECAM detection of an extremely bright burst
  62. IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube
  63. IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube
  64. IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube
  65. Fermi-LAT gamma-ray observations of IceCube-230112A
  66. IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube
  67. Fermi-LAT gamma-ray observations of IceCube-221223A
  68. IceCube-221216A: Upper limits from a search for additional neutrino events in IceCube
  69. IceCube-221124A: Upper limits from a search for additional neutrino events in IceCube
  70. IceCube-221104A: Upper limits from a search for additional neutrino events in IceCube
  71. Konus-Wind observation of the recent SGR 1935+2154 activity
  72. INTEGRAL detection of a burst from SGR J1935+2154
  73. IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
  74. IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
  75. IceCube-220629A: Upper limits from a search for additional neutrino events in IceCube
  76. IceCube-220627A: Upper limits from a search for additional neutrino events in IceCube
  77. IceCube-Cascade 220625A: Upper limits from a search for additional neutrino events in IceCube
  78. IceCube-220509A: Upper limits from a search for additional neutrino events in IceCube
  79. IceCube-220425A: Upper limits from a search for additional neutrino events in IceCube
  80. IceCube-220424A: Upper limits from a search for additional neutrino events in IceCube
  81. IceCube-220421A: Upper limits from a search for additional neutrino events in IceCube
  82. IceCube-220317A: Upper limits from a search for additional neutrino events in IceCube
  83. IceCube-220306A: Upper limits from a search for additional neutrino events in IceCube
  84. IceCube-220303A: Upper limits from a search for additional neutrino events in IceCube
  85. GRB 220228A: Fermi-LAT detection
  86. GRB 220101A: The first example of a Petanova
  87. IceCube-220205A: Upper limits from a search for additional neutrino events in IceCube
  88. IceCube-211216A: Upper limits from a search for additional neutrino events in IceCube
  89. IceCube-211216A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  90. IceCube-211208A: Upper limits from a search for additional neutrino events in IceCube
  91. IceCube-211208A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  92. IceCube-Cascade 211128A: Upper limits from a search for additional neutrino events in IceCube
  93. IceCube-211125A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  94. IceCube-211123A: Upper limits from a search for additional neutrino events in IceCube
  95. HAWC-211123A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  96. Konus-Wind observation of the recent SGR 1935+2154 activity
  97. IceCube-210730A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  98. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  99. INTEGRAL detection of a burst from SGR 1935+2154
  100. IceCube-210516A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation

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