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"

7447 results found.

  1. LIGO/Virgo S190706ai: Updated sky localization
  2. LIGO/Virgo S190707q: Updated sky localization
  3. GRB 190708B: Tiled Swift observations
  4. LIGO/Virgo S190706ai: No transient candidates from CALET observations
  5. LIGO/Virgo S190707q: Upper limits from Fermi-GBM Observations
  6. LIGO/Virgo S190707q: Upper limits from AGILE-GRID observations
  7. LIGO/Virgo S190707q: No counterpart candidates in HAWC observations
  8. LIGO/Virgo S190706ai: Upper limits from Fermi-GBM Observations
  9. LIGO/Virgo S190707q : No neutrino counterpart candidates in ANTARES search
  10. LIGO/Virgo S190707q: Identification of a GW compact binary merger candidate
  11. LIGO/Virgo S190707q: Upper limits from IceCube neutrino searches
  12. LIGO/Virgo S190706ai: No neutrino counterpart candidates in ANTARES search
  13. LIGO/Virgo S190706ai: No counterpart candidates in HAWC observations
  14. LIGO/Virgo S190706ai: Identification of a GW compact binary merger candidate
  15. LIGO/Virgo S190706ai: Upper limits from IceCube neutrino searches
  16. GRB 190706B: Swift detection of a burst
  17. Fermi-LAT Gamma-ray Observations of IceCube-190704A and detection of the new gamma-ray source 1WHSP J104516.2+275133
  18. LIGO/Virgo S190701ah: Updated sky localization
  19. IceCube-190704A: not observable by Fermi-GBM
  20. IceCube-190704A - IceCube observation of a high-energy neutrino candidate event
  21. LIGO/Virgo S190630ag: Gaia Photometric Alerts transient candidate
  22. LIGO/Virgo S190630ag: no counterpart candidate in the SVOM/GWAC observations
  23. LIGO/Virgo S190701ah: KMTNet Observation
  24. IPN triangulation of GRB 190630A (short)
  25. LIGO/Virgo S190701ah: Upper limits from Fermi-GBM Observations
  26. LIGO/Virgo S190630ag: Upper limits from CALET observations
  27. LIGO/Virgo S190701ah: No neutrino counterpart candidates in ANTARES search
  28. LIGO/Virgo S190701ah: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo S190701ah: Upper limits from IceCube neutrino searches
  30. GRB 190630C: KAIT Optical Upper Limit
  31. LIGO/Virgo S190630ag: No counterpart candidates in AGILE-GRID observations
  32. GRB 190701A: Swift detection of a burst
  33. GRB 190630B: KAIT Optical Afterglow Confirmation
  34. LIGO/Virgo S190630ag: Upper limits from Fermi-GBM Observations
  35. GRB 190630C: Swift detection of a burst
  36. LIGO/Virgo S190630ag: No neutrino counterpart candidates in ANTARES search
  37. LIGO/Virgo S190630ag: No counterpart candidates in HAWC observations
  38. LIGO/Virgo S190630ag: Identification of a GW compact binary merger candidate
  39. LIGO/Virgo S190630ag: Upper limits from IceCube neutrino searches
  40. IceCube-190629A: Upper limits from Fermi-GBM Observations
  41. GRB Swift Trigger 912102: KAIT Optical Afterglow Candidate
  42. Swift Trigger 912102: possible GRB 190630B
  43. IceCube-190629A - IceCube observation of a high-energy neutrino candidate event
  44. IceCube-190619A: prompt emission upper limits from AstroSat-CZTI
  45. IceCube-190619A: No counterpart candidates in ANTARES data
  46. LIGO/Virgo S190426c: Swift UVOT - no new counterpart candidates identified
  47. LIGO/Virgo S190510g: Swift UVOT - no new counterpart candidates identified
  48. IceCube-190619A - IceCube observation of a high-energy neutrino candidate event
  49. GRB 190610A: Swift/UVOT Upper Limits
  50. GRB 190610A: Swift-XRT observations
  51. GRB 190610A: Swift ToO observations
  52. GRB 190613B: Swift detection of a burst with an optical counterpart
  53. GRB 190613A: Swift detection of a burst with an optical counterpart
  54. GRB 190611A: Swift detection of a burst
  55. LIGO/Virgo S190425z: Swift UVOT - no new sources identified, and a summary of the Swift UVOT processing of GW triggers.
  56. LIGO/Virgo S190521r: Gaia Photometric Alerts transient candidate
  57. GRB 190604B: Swift detection of a burst
  58. LIGO/Virgo S190602aq: AstroSat CZTI upper limits
  59. LIGO/Virgo S190602aq: upper limit in INTEGRAL SPI-ACS prompt observations
  60. LIGO/Virgo S190602aq: Upper limits from Fermi-GBM Observations
  61. LIGO/Virgo S190602aq: No counterpart candidate in AGILE-MCAL observations
  62. LIGO/Virgo S190602aq: No neutrino counterpart candidates in ANTARES search
  63. LIGO/Virgo S190602aq: No counterpart candidates in HAWC observations
  64. LIGO/Virgo S190602aq: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo S190602aq: Upper limits from IceCube neutrino searches
  66. GRB 190531B: Swift ToO observations
  67. GRB 190530A: Swift-XRT afterglow detection
  68. LIGO/Virgo S190503bf: Gaia Photometric Alerts transient candidate
  69. GRB 190530A: Swift ToO observations
  70. LIGO/Virgo S190425z: No counterpart candidate in Zadko-GRANDMA observations.
  71. LIGO/Virgo S190521r : Gaia Photometric Alerts transient candidate
  72. LIGO/Virgo S190518bb: AstroSat CZTI upper limits
  73. LIGO/Virgo S190521g: AstroSat CZTI upper limits
  74. LIGO/Virgo S190517h: AstroSat CZTI upper limits
  75. LIGO/Virgo S190519bj: AstroSat CZTI upper limits
  76. LIGO/Virgo S190521r: No optical counterpart from SVOM/GWAC-F30 observations.
  77. LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC-F30 observations.
  78. LIGO/Virgo S190524q: Retraction of GW compact binary merger candidate
  79. LIGO/Virgo S190517h: Gaia Photometric Alerts transient candidate
  80. LIGO/Virgo S190521r: No candidate counterparts from ATLAS observations of the skymap
  81. LIGO/Virgo S190521r: No transient candidates from CALET observations
  82. LIGO/Virgo S190521g: Upper limits from CALET observations
  83. LIGO/Virgo S190521r: Upper limits from Fermi-GBM observations
  84. LIGO/Virgo S190521g : Upper limits from Fermi-GBM observations
  85. LIGO/Virgo S190521g: Updated sky localization
  86. LIGO/Virgo S190521g: No candidate counterpart in Fermi-LAT observations
  87. LIGO/Virgo S190521r: No counterpart candidate in AGILE-MCAL observations
  88. LIGO/Virgo S190521r: No neutrino counterpart candidates in ANTARES search
  89. LIGO/Virgo S190521r: Identification of a GW compact binary merger candidate
  90. LIGO/Virgo S190517h : No counterpart candidate in TAROT-GRANDMA observations.
  91. LIGO/Virgo S190521r: No counterpart candidates in HAWC observations
  92. LIGO/Virgo S190521g: No neutrino counterpart candidates in ANTARES search
  93. LIGO/Virgo S190521g: No counterpart candidates in HAWC observations
  94. LIGO/Virgo S190521g: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo S190519bj: Fermi GBM Observations
  96. LIGO/Virgo S190519bj: ANTARES neutrino search
  97. LIGO/Virgo S190519bj: HAWC follow-up
  98. LIGO/Virgo S190519bj: Identification of a GW compact binary merger candidate
  99. GRB 190519A: Swift detection of a burst
  100. LIGO/Virgo S190518bb: Retraction of GW compact binary merger candidate

Advanced

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