Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

5557 results found.

  1. GRB 190515A: Fermi GBM Final Real-time Localization
  2. LIGO/Virgo S190513bm : TAROT-Calern and TAROT-Chile (TCA/TCH)/GRANDMA observation report.
  3. LIGO/Virgo S190513bm: Lick/KAIT Follow-Up Observations
  4. LIGO/Virgo S190510g: Further KMTNet observation of DECam-GROWTH and DESGW candidates
  5. LIGO/Virgo S190513bm Global MASTER-Net observations report
  6. LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
  7. LIGO/Virgo S190512at Global MASTER-Net observations report
  8. LIGO/Virgo S190512at: INTEGRAL inactive at the time of the event
  9. Fermi GRB190512.62 Global MASTER-Net observations report
  10. Fermi GRB190512.61 Global MASTER-Net observations report
  11. LIGO/Virgo S190510g: DOAO Observation
  12. LIGO/Virgo S190510g: MASTER OT detection inside low surface brightness galaxy
  13. LIGO/Virgo S190510g: GRAWITA VST-ESO PARANAL optical observations
  14. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  15. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  16. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  17. LIGO/Virgo S190510g: Lulin Optical Follow-up Observations
  18. LIGO/Virgo S190425z: CAHA-GRANDMA Observation of the Swift UVOT Source
  19. LIGO/Virgo S190510g: HSC Y-band follow-up observation
  20. LIGO/Virgo S190510g: MAXI/GSC Observations
  21. Fermi GRB190510.12 Global MASTER-Net observations report
  22. LIGO/Virgo S190510g: IceCube Neutrino Search
  23. LIGO/Virgo S190503bf: TAROT-GRANDMA observation report
  24. GRB 190507B: GOTO optical counterpart search
  25. Fermi GRB190508.11 Global MASTER-Net observations report
  26. Fermi GRB190507.27 Global MASTER-Net observations report
  27. IceCube-190504A: MASTER optical monitoring analysis
  28. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  29. Search for additional neutrino events from the direction of IceCube-190504A with IceCube
  30. Search for additional neutrino events from the direction of IceCube-190503A with IceCube
  31. LIGO/Virgo S190503bf: CALET Observations
  32. IceCube-190503A: Insight-HXMT/HE observation
  33. Fermi GRB190505.05 Global MASTER-Net observations report
  34. Fermi GRB190504.68 Global MASTER-Net observations report
  35. LIGO/Virgo S190503bf Global MASTER-Net observations report
  36. IceCube-190503A: Lick/KAIT Follow-Up Observations
  37. LIGO/Virgo S190503bf: Fermi-LAT search for a high-energy gamma-ray counterpart
  38. LIGO/Virgo S190503bf: Insight-HXMT/HE observation
  39. IceCube-190503A: Insight-HXMT/HE observation
  40. LIGO/Virgo S190503bf: ANTARES neutrino search
  41. Fermi-LAT Gamma-ray Observations of IceCube-190503A
  42. LIGO/Virgo S190503bf: MAXI/GSC Observations
  43. LIGO/Virgo S190503bf: AGILE-GRID Observations
  44. IceCube-190503A: INTEGRAL prompt observation
  45. LIGO/Virgo S190503bf: INTEGRAL prompt observation
  46. LIGO/Virgo S190503bf: AGILE MCAL observations
  47. IceCube-190503A - IceCube observation of a high-energy neutrino candidate event
  48. LIGO/Virgo S190503bf: Identification of a GW compact binary merger candidate
  49. LIGO/Virgo S190503bf: IceCube Neutrino Search
  50. Fermi GRB190429.74 Global MASTER-Net observations report
  51. LIGO/Virgo S190426c: YAHPT Optical Observation
  52. LIGO/Virgo S190426c: Continued infrared wide-field search with Palomar Gattini-IR
  53. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  54. LIGO/Virgo S190425z: 1.5m OSN and 10.4m imaging of the UVOT source field
  55. LIGO/Virgo S190425z: SVOM/GWAC-F60A observations
  56. LIGO/Virgo S190425z: Liverpool Telescope imaging of ZTF19aasckkq
  57. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  58. LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
  59. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  60. LIGO/Virgo S190426c: MMT Follow-Up Observations
  61. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  62. LIGO/Virgo S190426c: Infrared Wide-field Search with Palomar Gattini-IR
  63. LIGO/Virgo S190426c: Swift-XRT sources
  64. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  65. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  66. LIGO/Virgo S190426c: Nemo is Unrelated
  67. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  68. LIGO/Virgo S190425z: RATIR Observations of Galaxies
  69. LIGO/Virgo S190425z: YAHPT Optical Observation
  70. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  71. LIGO/Virgo S190425z: KMTNet Observation
  72. LIGO/Virgo S190425z: ZTF19aarzaod 1.5m OSN imaging and 10.4m GTC spectroscopy
  73. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  74. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  75. Fermi GRB190425.09 Global MASTER-Net observations report
  76. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  77. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  78. Fermi GRB190422.96 Global MASTER-Net observations report
  79. Fermi GRB190422.67 Global MASTER-Net observations report
  80. LIGO/Virgo S190421ar Global MASTER-Net observations report
  81. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  82. Fermi GRB190419.41 Global MASTER-Net observations report
  83. Fermi GRB190418.92 Global MASTER-Net observations report
  84. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  85. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  86. LIGO/Virgo S190412m: MAXI/GSC Observations
  87. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  88. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  89. LIGO/Virgo S190408an: MASTER 3 OT's more detection
  90. LIGO/Virgo S190408an: MASTER OT is 27 day old ATLAS SN candidate and unrelated
  91. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  92. GRB 140408A: MAXI/GSC detection
  93. GRB 140404B: MAXI/GSC detection
  94. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  95. GRB 190331B: Swift observations of a ground-detected burst
  96. Fermi-LAT Gamma-ray Observations of IceCube-190331A
  97. Search for additional neutrino events from the direction of IceCube-190331A with IceCube
  98. GRB 190331C: Insight-HXMT/HE detection
  99. GRB 190331A: Insight-HXMT/HE detection
  100. GRB 190330A: 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