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"

11523 results found.

  1. GRB 190829A: LCO Optical Afterglow Detection
  2. Fermi trigger No 589223981 Global MASTER-Net observations report
  3. GRB 190903A: Fermi GBM detection
  4. GRB 190903A: Fermi GBM Final Real-time Localization
  5. LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
  6. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  7. Fermi GBM trigger 589060361/190901828 is not a GRB
  8. Fermi trigger No 589065714 Global MASTER-Net observations report
  9. GRB 190901A: BALROG localization (Fermi Trigger 589065714 / GRB 190901890)
  10. GRB 190901A: Fermi GBM Final Real-time Localization
  11. Fermi trigger No 589060361 Global MASTER-Net observations report
  12. GRB 190829A: Liverpool Telescope observations
  13. Fermi trigger No 588962322 Global MASTER-Net observations report
  14. GRB 190829A: NOEMA detection of the mm afterglow
  15. Fermi trigger No 588931056 Global MASTER-Net observations report
  16. GRB 190831A: Fermi GBM Final Real-time Localization
  17. GRB 190829A: UKIRT detection of the NIR Afterglow
  18. GRB 190829A: MMT detection of the optical afterglow
  19. GRB 190829A: No Neutrino Counterpart detected with ANTARES
  20. GRB 190829A, Swift-BAT refined analysis
  21. GRB 190829A: AGILE-GRID upper limits
  22. GRB 190829A: AGILE ratemeters detection and MCAL upper limits
  23. GRB 190829A: Fermi GBM detection
  24. GRB 190829A: Fermi-LAT Upper Limits
  25. GRB 190829A:: Global MASTER-net optical clear and polarization observations scheduler and some spiculations
  26. Fermi trigger No 588838851 Global MASTER-Net observations report
  27. GRB 190829A: 10.4m GTC spectroscopy
  28. GRB 190830B: Fermi GBM Final Real-time Localization
  29. GRB 190830A: Fermi GBM Final Real-time Localization
  30. GRB 190829A: GROWTH India detection of afterglow
  31. Fermi trigger No 588801358 Global MASTER-Net observations report
  32. GRB 190829A: Swift detection of a burst consistent with a galaxy at z=0.08
  33. GRB 190829A: Fermi GBM Final Real-time Localization
  34. GRB 190828B: VLT/X-shooter optical afterglow candidate
  35. LIGO/Virgo S190828l: No counterpart candidates in Fermi-LAT observations
  36. GRB 190828B: Fermi GBM observation
  37. LIGO/Virgo S190828j: No counterpart candidates in Fermi-LAT observations
  38. LIGO/Virgo S190828l: Upper limits from Fermi-GBM Observations
  39. LIGO/Virgo S190828j: Upper limits from Fermi-GBM Observations
  40. GRB 190828C: BALROG localization (Fermi Trigger 588696271 / GRB 190828614)
  41. GRB 190828C: Fermi GBM Final Real-time Localization
  42. GRB 190828B: Fermi GBM Final Real-time Localization
  43. LIGO/Virgo S190814bv: DESGW non-detection of AT2019osy/ASKAP 005547-270433
  44. Fermi trigger No 588597173 Global MASTER-Net observations report
  45. Fermi GBM-190816: Eight additional candidates from the Zwicky Transient Facility
  46. GRB 190827A: BALROG localization (Fermi Trigger 588597173 / GRB 190827467)
  47. GRB 190827A: Fermi GBM Final Real-time Localization
  48. LIGO/Virgo S190814bv: Final list of candidates from the DESGW coadd analysis from the week long search campaign
  49. Fermi trigger No 588398821 Global MASTER-Net observations report
  50. GRB 190825A: Fermi GBM Final Real-time Localization
  51. GRB 190824A: Fermi GBM observation
  52. Fermi trigger No 588350802 Global MASTER-Net observations report
  53. Fermi GBM-190816: Updated localization of subthreshold GRB-GW candidate
  54. GRB 190824A: Fermi GBM Final Real-time Localization
  55. Fermi trigger No 588185734 Global MASTER-Net observations report
  56. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  57. Fermi trigger No 588115134 Global MASTER-Net observations report
  58. Fermi GBM-190816: MASTER-Net optical observation report
  59. LIGO/Virgo S190814bv: new candidate from DESGW
  60. GRB 190821A: Fermi GBM observation
  61. Fermi GBM-190816: Upper Limits from Swift/BAT Observations
  62. Fermi GBM-190816: Correction from the Zwicky Transient Facility
  63. Fermi GBM-190816: Four additional candidates from the Zwicky Transient Facility
  64. Fermi trigger No 588100239 Global MASTER-Net observations report
  65. Fermi GBM-190816: No counterpart candidates in Fermi-LAT observations
  66. LIGO/Virgo S190814bv: further candidates from DESGW
  67. Fermi GBM-190816: AGILE in SAA at T0
  68. Fermi GBM-190816: ZTF19abqanpy 10.4m GTC spectroscopy
  69. Fermi-LAT Gamma-ray Observations of IceCube-190819A
  70. Fermi GBM-190816: One candidate counterpart from the Zwicky Transient Facility
  71. LIGO/Virgo GBM-190816: no counterpart candidates in the Swift/BAT Observations
  72. Fermi GBM-190816: Upper limits from IceCube neutrino searches
  73. IceCube-190819A: MASTER analysis
  74. Fermi GBM-190816: No counterpart candidates in HAWC observations
  75. Fermi GBM-190816+LIGO/Virgo : no neutrino counterpart candidate in ANTARES search
  76. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  77. Fermi GBM-190816: A subthreshold GRB candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  78. IceCube-190819A: Upper limits from Fermi-GBM Observations
  79. IceCube-190819A - IceCube observation of a high-energy neutrino candidate event
  80. LIGO/Virgo S190814bv: DESGW candidate update
  81. Fermi trigger No 587775150 Global MASTER-Net observations report
  82. GRB 190817A: Fermi GBM Final Real-time Localization
  83. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  84. LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
  85. GRB 190813A: Insight-HXMT/HE detection
  86. GRB 190814A: Insight-HXMT/HE detection
  87. LIGO/Virgo S190814bv: No candidates identified in DECam data by visual inspection
  88. Fermi trigger No 587505927 Global MASTER-Net observations report
  89. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  90. IPN triangulation of GRB 190813A (short)
  91. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  92. GRB 190814A: Fermi GBM Final Real-time Localization
  93. Fermi trigger No 587392154 Global MASTER-Net observations report
  94. GRB 190813A: Fermi GBM Final Real-time Localization
  95. IPN triangulation of GRB 190805B
  96. IPN triangulation of GRB 190810A (short)
  97. Fermi trigger No 587084236 Global MASTER-Net observations report
  98. GRB 190810A: Fermi GBM Final Real-time Localization
  99. HAWC-190806A: Upper limits from Fermi-GBM Observations
  100. GRB 190726A: Insight-HXMT/HE detection

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov