Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

11105 results found.

  1. GRB 200212A: Fermi GBM Final Localization Correction
  2. Fermi trigger No 603197394: Global MASTER-Net observations report
  3. GRB 200212A: Fermi GBM Final Real-time Localization
  4. GRB 200211A: BALROG localization (Fermi Trigger 603098793 / GRB 200211310)
  5. GRB 200211A: Fermi GBM Final Real-time Localization
  6. GRB 200207A: AstroSat CZTI detection
  7. LIGO/Virgo S200208q: No counterpart candidates in Fermi-LAT observations
  8. GRB 200120A: Fermi GBM observation
  9. LIGO/Virgo S200208q: Upper limits from Fermi-GBM Observations
  10. Fermi trigger No 602817262: Global MASTER-Net observations report
  11. GRB 200208A: Fermi GBM Final Real-time Localization
  12. Fermi trigger No 602731380: Global MASTER-Net observations report
  13. GRB 200207A: Fermi GBM Final Real-time Localization
  14. GRB 200206A: Fermi GBM Final Real-time Localization
  15. Fermi trigger No 602626648: Global MASTER-Net observations report
  16. GRB 200205C: Fermi GBM Final Real-time Localization
  17. GRB200120A: SRG/eROSITA discovery of X-ray afterglow
  18. Fermi trigger No 602455182: Global MASTER-Net observations report
  19. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  20. GRB200120A: SRG/ART-XC Upper Limit
  21. Fermi trigger No 602392636: Global MASTER-Net observations report
  22. ZTF20aajnksq: Occulted by Earth at the time of GRB 200128A
  23. GRB 200203A: Fermi GBM Final Real-time Localization
  24. ZTF Discovery of ZTF20aajnksq: a Rapidly Fading Luminous Transient in the GRB 200128A Localiziation Region
  25. GRB 200201A: Fermi GBM Final Real-time Localization
  26. Konus-Wind observation of GRB 200125B
  27. Konus-Wind observation of GRB 200130B
  28. IPN triangulation of GRB 200130B
  29. Fermi trigger No 602071201: Global MASTER-Net observations report
  30. GRB 200130B: BALROG localization (Fermi Trigger 602071201 / GRB 200130417)
  31. GRB 200130B: Fermi GBM Final Real-time Localization
  32. Fermi trigger No 602056641: Global MASTER-Net observations report
  33. GRB 200130A: Fermi GBM Final Real-time Localization
  34. LIGO/Virgo S200129m: No counterpart candidates in Fermi-LAT observations
  35. LIGO/Virgo S200129m: Not observable by Fermi-GBM
  36. GRB 200129A: Fermi GBM Final Real-time Localization
  37. LIGO/Virgo S200128d: No counterpart candidates in Fermi-LAT observations
  38. Fermi-LAT ANTARES coincidence: IceCube neutrino search
  39. Fermi-LAT ANTARES 200127.79 coincidence: MASTER alert observation and presence of young pulsar close to error-box
  40. IPN triangulation of GRB 200125B
  41. LIGO/Virgo S200128d: Upper limits from Fermi-GBM Observations
  42. Fermi-LAT-ANTARES coincidence
  43. GRB 200125B: DDOTI/OAN optical observations report
  44. GRB 200128A: Fermi GBM Final Real-time Localization
  45. Fermi trigger No 601841483: Global MASTER-Net observations report
  46. GRB 200127B: Fermi GBM Final Real-time Localization
  47. GRB 200125B: Fermi GBM observations
  48. Fermi trigger No 601729856: Global MASTER-Net observations report
  49. GRB 200125B: Insight-HXMT/HE detection
  50. Fermi trigger No 601677816: Global MASTER-Net observations report
  51. GRB 200125B: BALROG localization (Fermi Trigger 601677816 / GRB 200125864)
  52. GRB 200125B: Fermi GBM Final Real-time Localization
  53. GRB 200122B: Insight-HXMT/HE detection
  54. Fermi trigger No 601363105: Global MASTER-Net observations report
  55. Konus-Wind observation of GRB 200120A
  56. IPN Triangulation of GRB 200120A
  57. GRB 200120A: AstroSat CZTI detection
  58. Fermi-LAT Gamma-ray Observations of IceCube-200120A
  59. Fermi trigger No 601254300: Global MASTER-Net observations report
  60. GRB 191031D: XMM-Newton upper limit
  61. GRB 200120A: Insight-HXMT/HE detection
  62. IceCube-200120A: not observable by Fermi-GBM
  63. GRB 200120A: Fermi GBM Final Real-time Localization
  64. Fermi-LAT Gamma-ray Observations of IceCube-200117A
  65. IceCube-200117A: Upper limits from Fermi-GBM Observations
  66. GRB 200117A: Fermi GBM Final Real-time Localization
  67. GRB 200111A: CALET Gamma-Ray Burst Monitor detection
  68. GRB 200111A: AstroSat CZTI detection
  69. IPN triangulation of GRB 200111A
  70. LIGO/Virgo S200115j: No counterpart candidates in Fermi-LAT observations
  71. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  72. GRB 200114A: Insight-HXMT/HE detection
  73. GRB 200114A: DDOTI/OAN optical observations report
  74. GRB 200114A: AstroSat CZTI detection
  75. LIGO/Virgo S200114f: No counterpart candidates in Fermi-LAT observations
  76. LIGO/Virgo S200114f: Upper limits from Fermi-GBM Observations
  77. Fermi trigger No 600666048: Global MASTER-Net observations report
  78. GRB 200114A: BALROG localization (Fermi Trigger 600666048 / GRB 200114153)
  79. GRB 200114A: Fermi GBM Final Real-time Localization
  80. GRB 200112A: AstroSat CZTI detection
  81. Fermi-LAT Gamma-ray Observations of IceCube-200109A and detection of a possible new gamma-ray source, Fermi J1055.8+1034
  82. LIGO/Virgo 200112r: No counterpart candidates in Fermi-LAT observations
  83. LIGO/Virgo S200112r: not observable by Fermi-GBM
  84. LIGO/Virgo S200112r: not observable by Fermi-GBM
  85. GRB 200111A: Insight-HXMT/HE detection
  86. GRB 200112A: BALROG localization (Fermi Trigger 600525396 / GRB 200112525)
  87. Fermi trigger No 600525396: Global MASTER-Net observations report
  88. GRB 200112A: Fermi GBM Final Real-time Localization
  89. GRB 200109A: Insight-HXMT/HE detection
  90. Fermi-LAT ANTARES coincidence: No significant detection in HAWC
  91. Fermi trigger No 600448273: Global MASTER-Net observations report
  92. GRB 200111A: Fermi GBM Final Real-time Localization
  93. ANTARES 200108A: No detection by Swift-XRT
  94. IceCube-200109A: Upper limits from Fermi-GBM Observations
  95. IceCube-200109A: IceCube observation of a high-energy neutrino candidate event
  96. Swift follow-up observations of IceCube-200107A: Identification of X-ray high state for 4FGL J0955.1+3551
  97. GRB 200109A: Fermi GBM observation
  98. Fermi-LAT ANTARES coincidence /ANTARES alert 200108.39: MASTER alert and inspect observation
  99. Fermi-LAT ANTARES coincidence: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  100. Fermi trigger No 600227156: Global MASTER-Net observations report

Advanced

Download all Circulars as a .tar.gz archive:
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