Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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.

Advanced Search Examples (click to copy):

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

900 results found.

  1. IceCube-260919A: Upper limits from a search for additional neutrino events in IceCube
  2. IceCube-260916A: Upper limits from a search for additional neutrino events in IceCube
  3. IceCube-260827A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube-260821A: Upper limits from a search for additional neutrino events in IceCube
  5. GRB 260317A: SVOM/ECLAIRs detection through offline targeted search and its possible association to magnetar 1E 1841-04.5
  6. IceCube-Cascade 260801A: Upper limits from a search for additional neutrino events in IceCube
  7. GRB 260802A / EP J223759.5+531421: SVOM/VT optical upper limit
  8. IceCube-260708A: Upper limits from a search for additional neutrino events in IceCube
  9. Konus-Wind detection of a burst from SGR 1E1841-045 on 2026 May 2
  10. GRB 260504B: SVOM/MXT refined analysis and potential detection
  11. SVOM/GRM observation of a bright burst from SGR 1E1841-045
  12. IPN triangulation of a bright burst from SGR 1E1841-045
  13. The EP-WXT trigger 01709259621 is likely a flaring star
  14. The EP-WXT trigger 01709259615 is likely a flaring star
  15. IceCube-260217A: Upper limits from a search for additional neutrino events in IceCube
  16. IceCube-260125A: Upper limits from a search for additional neutrino events in IceCube
  17. IceCube-260115A: Upper limits from a search for additional neutrino events in IceCube
  18. GRB 251219A: GECAM-B detection of a possible magnetar X-ray burst from SGR 1830-0645
  19. The EP-WXT trigger 01709248783 is likely a flaring star
  20. LIGO/Virgo/KAGRA S251112cm: Upper limits from Glowbug gamma-ray observations
  21. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 4-Update Localization Volume
  22. IceCube-251025A: Upper limits from a search for additional neutrino events in IceCube
  23. Upper limits from a search for additional neutrino events in IceCube
  24. IceCube-250926A: Upper limits from a search for additional neutrino events in IceCube
  25. IceCube-250831A: Upper limits from a search for additional neutrino events in IceCube
  26. GRB 250815A: Fermi GBM Final Localization
  27. IceCube-250813A: Upper limits from a search for additional neutrino events in IceCube
  28. The EP-WXT trigger 01709198251 is likely a flaring star
  29. Swift detection of the Soft Gamma Repeater PSR J1647-4552
  30. EP250702a/ GRB 250702B: NuSTAR X-ray Observations
  31. GRB 250706B: refined SVOM/MXT data analysis
  32. Fermi Gamma-ray Burst Monitor trigger 772838080/250628885 is not a GRB
  33. GRB 250621B: SVOM/GRM detection of a possible magnetar X-ray burst
  34. The EP-WXT trigger 01709179071 is likely a flaring star
  35. The EP-WXT trigger 01709178975 is likely a flaring star
  36. GRB 250507A: refined SVOM/MXT data analysis
  37. IceCube-250416A: Upper limits from a search for additional neutrino events in IceCube
  38. GRB 250331C: Swift/UVOT Upper Limits
  39. IceCube-250330A: Upper limits from a search for additional neutrino events in IceCube
  40. IceCube-250309A: Upper limits from a search for additional neutrino events in IceCube
  41. IceCube-250302A: Upper limits from a search for additional neutrino events in IceCube
  42. IceCube-Cascade 250215A: Upper limits from a search for additional neutrino events in IceCube
  43. LIGO/Virgo/KAGRA S250206dm: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  44. GECAM-A detection of a bright burst from SGR 1E1841-045
  45. Konus-Wind detection of a bright burst from SGR 1E1841-045 on 2025 January 23
  46. IPN triangulation of a bright burst from SGR 1E1841-045
  47. GRB 250116A: GECAM-B detection of a long burst
  48. IceCube-250102A: Upper limits from a search for additional neutrino events in IceCube
  49. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  50. GRB 241130A: EIRSAT-1 GMOD Detection
  51. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  52. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  53. SVOM/GRM detection of a short burst from SGR 1830
  54. GECAM detection of a short burst from SGR 1830
  55. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  56. EP241113a: Swift XRT weak detection
  57. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  58. SVOM/GRM detection of a short burst from SGR 1E1841-045
  59. INTEGRAL detection of a burst from 1E 1841-045
  60. EP241107a: EP on-board trigger and autonomous follow-up observation
  61. EP241025a (GRB 241025A): EP observations update
  62. GRB241017A: TOO Observations by SVOM/MXT
  63. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  64. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  65. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  66. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  67. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  68. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  69. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  70. GRB 240824A: Swift/UVOT Upper Limits
  71. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  72. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  73. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  74. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  75. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  76. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  77. IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
  78. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  79. IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
  80. IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
  81. IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
  82. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  83. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  84. IceCube-240123A: Upper limits from a search for additional neutrino events in IceCube
  85. IPN triangulation of GRB 240112A (long)
  86. GRB 240112A: GECAM detection of a burst
  87. GRB 240106A: Glowbug gamma-ray detection
  88. IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
  89. IceCube-231211A: Upper limits from a search for additional neutrino events in IceCube
  90. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  91. GECAM-B observation of a short burst from SGR J1555-5402
  92. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  93. Fermi GRB 231108A: Global MASTER-Net observations report
  94. LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  96. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  97. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  98. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  99. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  100. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov