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 S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  2. LIGO/Virgo S190814bv: Not observable by CALET
  3. LIGO/Virgo S190814bv: Pan-STARRS imaging indicates DG19sevhc (AT2019npy) is a proper motion star
  4. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  5. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  6. LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
  7. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  8. LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
  9. LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
  10. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  11. S190814bv: MASTER analysis of DECam-GROWTH candidates
  12. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  13. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  14. LIGO/Virgo S190814bv: No candidates identified in DECam data by visual inspection
  15. LIGO/Virgo S190814bv: des-gw190814b is a moving object
  16. LIGO/Virgo S190814bv: ATLAS forced photometry non-detections of DESGW candidates
  17. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  18. LIGO/Virgo S190814bv: KMTNet observation
  19. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  20. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  21. LIGO/Virgo S190814bv: Upper limits from AGILE-GRID observations
  22. LIGO/Virgo S190814bv: Update on Sky-Localization and Source-Classification
  23. LIGO/Virgo S190814bv: no candidates from WHT imaging of candidate galaxies
  24. LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
  25. LIGO/Virgo S190814bv : no neutrino counterpart candidate in ANTARES search
  26. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  27. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  28. LIGO/Virgo S190814bv: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo S190814bv: Upper limits from IceCube neutrino searches
  30. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  31. HAWC-190806A: Swift-XRT observations
  32. Trigger_11505: Tiled Swift observations
  33. LIGO/Virgo S190728q: New optical candidates from the DESGW program
  34. LIGO/Virgo S190808ae: Retraction of GW compact binary merger candidate
  35. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  36. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  37. LIGO/Virgo S190808ae: One Coincident Neutrino Candidate from IceCube Search
  38. LIGO/Virgo S190808ae: Identification of a GW compact binary merger candidate
  39. GRB 190805B: Tiled Swift observations
  40. GRB 190804B: Tiled Swift observations
  41. IceCube 190730A: No counterpart candidates or blazar activity in GOTO observations
  42. GRB 190719C: VLT/X-shooter spectroscopic redshift of the host galaxy
  43. LIGO/Virgo S190727h: Updated sky localization
  44. GRB 190731A: Swift ToO observations
  45. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  46. IceCube 190730A: not observable by Fermi-GBM
  47. LIGO/Virgo S190707q: AstroSat CZTI upper limits
  48. LIGO/Virgo S190718y: AstroSat CZTI upper limits
  49. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  50. LIGO/Virgo S190720a: AstroSat CZTI upper limits
  51. IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
  52. LIGO/Virgo S190727h: Gaia Photometric Alerts transient candidate
  53. LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
  54. LIGO/VIRGO S190728q: No candidate counterparts from ATLAS observations
  55. LIGO/Virgo S190728q: Third update on neutrino search with IceCube
  56. LIGO/Virgo S190728q: Update on Sky-Localization and Source-Classification
  57. LIGO/Virgo S190728q: ZTF19abjethn is inconsistent with new GW localization
  58. LIGO/Virgo S190728q: Identification of a Faint Blue Static Source at the Location of ZTF19abjethn
  59. LIGO/Virgo S190728q: Photometric Redshift and Stellar Mass Estimates for the Potential Host Galaxy of Optical Counterpart Candidate ZTF19abjethn
  60. LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
  61. LIGO/Virgo S190728q: Second update on neutrino search with IceCube
  62. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  63. LIGO/Virgo S190728q: no counterpart candidates in AGILE-GRID observations
  64. LIGO/Virgo S190728q : no neutrino counterpart candidate in ANTARES search
  65. LIGO/Virgo S190728q: One neutrino candidate from IceCube search
  66. LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
  67. LIGO/Virgo S190728q: Identification of a GW compact binary merger candidate
  68. LIGO/Virgo S190728q: Upper limits from IceCube neutrino searches
  69. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  70. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  71. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  72. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  73. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  74. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  75. LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches
  76. LIGO/Virgo S190718y: Gaia Photometric Alerts transient candidates
  77. LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
  78. LIGO/Virgo S190720a: Upper limits from CALET observations
  79. GRB 190719C: Swift/UVOT Upper Limits
  80. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  81. LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
  82. LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
  83. LIGO/Virgo S190720a: AGILE-MCAL observations
  84. LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
  85. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
  86. LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches
  87. GRB 190719C: NOT candidate optical afterglow and host
  88. LIGO/Virgo S190718y: ZTF pre-detection of MASTER candidate AT2019lly
  89. LIGO/Virgo S190718y: Analysis update
  90. GRB 190719C: Swift detection of a burst
  91. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  92. LIGO/Virgo S190630ag: Updated sky localization
  93. LIGO/Virgo S190718y : no neutrino counterpart candidate in ANTARES search
  94. LIGO/Virgo S190718y: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo S190718y: Upper limits from IceCube neutrino searches
  96. GRB 190718A: Swift detection of a burst
  97. GRB 190714A: Tiled Swift observations
  98. IceCube-190712A: No neutrino counterpart candidates in ANTARES search
  99. IceCube-190712A: Upper limits from Fermi-GBM Observations
  100. IceCube-190712A - IceCube observation of a high-energy neutrino candidate event

Advanced

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