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"

11854 results found.

  1. Konus-Wind observation of GRB 200219C
  2. Konus-Wind observation of GRB 200219A
  3. LIGO/Virgo S200219ac: Upper limits from Konus-Wind observations
  4. LIGO/Virgo S200213t: Upper limits from Konus-Wind observations
  5. LIGO/Virgo S200208q: Upper limits from Konus-Wind observations
  6. LIGO/Virgo S200225q: no counterpart candidate in SVOM/GWAC observations
  7. LIGO/Virgo S200224ca: No counterpart candidates in KAIT observations
  8. LIGO/Virgo S200224ca: GRAWITA-Campo Imperatore observations.
  9. Fermi trigger No 604231129: Global MASTER-Net observations report
  10. LIGO/Virgo S200225q: No counterpart candidates in Fermi-LAT observations
  11. LIGO/Virgo S200225q: No counterpart candidates in HAWC observations
  12. LIGO/Virgo S200225q: Global MASTER-Net observations report
  13. LIGO/Virgo S200224ca: No counterpart candidates in Fermi-LAT observations
  14. LIGO/Virgo S200225q: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S200224ca: Coverage and upper limits from MAXI/GSC observations
  16. GRB 200224A: Swift-XRT refined Analysis
  17. Fermi trigger No 604213554: Global MASTER-Net observations report
  18. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  19. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC observations
  20. LIGO/Virgo S200219ac : No significant candidates in TAROT - FRAM - GRANDMA observations.
  21. GRB 200219A: FRAM-Auger optical limit
  22. GRB 200219C: Mondy and TSHAO optical observations
  23. GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS
  24. LIGO/Virgo S200219ac: No counterpart candidates in KAIT observations
  25. GRB 200219C: DDOTI Observations
  26. LIGO/Virgo S200213t: AT2020clw/ZTF20aanaoyz, AT2020crd/ZTF20aanakge and AT2020cly/ZTF20aanakes 10.4m GTC spectroscopy
  27. LIGO/Virgo S200213t: Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
  28. GRB 200219C: Fermi-LAT detection
  29. GRB 200219A, Swift-BAT refined analysis
  30. Fermi trigger No 603849435: Global MASTER-Net observations report
  31. LIGO/Virgo S200219ac: No counterpart candidates in Fermi-LAT observations
  32. GRB 200219A: Swift-XRT refined Analysis correction
  33. LIGO/Virgo S200219ac: No counterpart candidates in HAWC observations
  34. LIGO/Virgo S200219ac: Coverage and upper limits from MAXI/GSC observations
  35. GRB 200219A: Swift detection of a short burst
  36. Swift GRB200219.32: Global MASTER-Net observations report
  37. GRB 200216B: Mondy and AbAO optical upper limits
  38. GRB 200216B: Swift-XRT refined Analysis
  39. LIGO/Virgo S200213t : No significant candidates in FRAM - OAJ - TAROT - GRANDMA observations
  40. LIGO/Virgo S200213t: AstroSat CZTI upper limits
  41. GRB 200216B: Swift detection of a burst
  42. Swift GRB200216.56: Global MASTER-Net observations report
  43. LIGO/Virgo S200213t: Updated coverage and candidate list for the Zwicky Transient Facility
  44. LIGO/Virgo S200213t: CLU/NED Galaxies in the 4-Update Localization Volume
  45. LIGO/Virgo S200213t: Possible host galaxies in the bilby skymap
  46. GRB 200215A: Liverpool Telescope upper limits
  47. Swift GRB200215.61: Global MASTER-Net observations report
  48. GRB 200215A: Swift detection of a burst
  49. LIGO/Virgo S200213t: MASTER possible Kilonova candidate in PGC315337
  50. LIGO/Virgo S200213t: No counterpart candidates from Nanshan-0.6m observations
  51. LIGO/Virgo S200213t: More Candidates from the Zwicky Transient Facility
  52. LIGO/Virgo S200213t: No counterpart candidates in KAIT observations
  53. LIGO/Virgo S200213t: AT2020ciz/ZTF20aamvnat, AT2020cjb/ZTF20aamvnth and 2020cjf/ZTF20aamvodd 10.4m GTC spectroscopy
  54. LIGO/Virgo S200213t: No counterpart candidates in Fermi-LAT observations
  55. LIGO/Virgo S200213t: No Counterparts in DDOTI/OAN Optical Observations
  56. LIGO/Virgo S200213t: AT2020ciy/ZTF20aamvqxl, AT2020cjg/ZTF20aamvoxx and AT2020cje/ZTF20aamvtip 10.4m GTC spectroscopy
  57. LIGO/Virgo S200213t: MANGROVE catalog galaxy ranking
  58. LIGO/Virgo S191213g: AT2019wxt Wendelstein optical observations
  59. LIGO/Virgo S200208q : No significant candidates in TAROT - FRAM - GRANDMA observations
  60. LIGO/Virgo S200213t: Coverage and upper limits from MAXI/GSC observations
  61. LIGO/Virgo trigger S200213t: Possible host galaxies
  62. LIGO/Virgo S200213t: NED Galaxies in the 90% Localization Volume
  63. ZTF20aajnksq: Upper limits from Konus-Wind observations
  64. GRB 200131A: Tautenburg observations
  65. Konus-Wind observation of GRB 200205B
  66. LIGO/Virgo S200208q: No counterpart candidates in KAIT observations
  67. LIGO/Virgo S200208q: No counterpart candidates in Fermi-LAT observations
  68. GRB 200120A: Fermi GBM observation
  69. LIGO/Virgo S200208q: Coverage and upper limits from MAXI/GSC observations
  70. LIGO/Virgo S200208q: No counterpart candidates in HAWC observations
  71. Fermi trigger No 602817262: Global MASTER-Net observations report
  72. GRB 200205B: Swift-BAT refined analysis
  73. Fermi trigger No 602731380: Global MASTER-Net observations report
  74. GRB 200205B: Swift-XRT refined Analysis
  75. GRB 200205B: LCO Optical Detection
  76. GRB 200205C: Fermi GBM Final Real-time Localization
  77. GRB 200205B: Swift detection of a burst with optical counterpart
  78. Swift GRB200205.81: Global MASTER-Net observations report
  79. MeerKAT observation of GRB 191221B
  80. GRB 200205A: MAXI/GSC detection
  81. MAXI GRB200205.29: Global MASTER-Net observations report
  82. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  83. LIGO/Virgo S200129m: Upper limits from Konus-Wind observations
  84. LIGO/Virgo S200128d: Upper limits from Konus-Wind observations
  85. Konus-Wind observation of GRB 200131A
  86. GRB 200131A: VIRT optical transient detection
  87. GRB 200201A: Fermi GBM Final Real-time Localization
  88. Swift GRB200131.95: Global MASTER-Net observations report
  89. Konus-Wind observation of GRB 200125B
  90. Konus-Wind observation of GRB 200130B
  91. IPN triangulation of GRB 200130B
  92. LIGO/Virgo S200128d: no counterpart candidate in SVOM/GWAC observations
  93. LIGO/Virgo S200128d : No significant candidates in FRAM - TAROT - GRANDMA observations
  94. LIGO/Virgo S200129m: NED Galaxies in the 50% Localization Volume
  95. LIGO/Virgo S200129m: No counterpart candidates in Fermi-LAT observations
  96. Konus-Wind observation of GRB 200125A
  97. LIGO/Virgo S200128d: upper limits from AGILE/GRID observations
  98. LIGO/Virgo S200129m: Coverage and upper limits from MAXI/GSC observations
  99. LIGO/Virgo S200128d: No counterpart candidates in Fermi-LAT observations
  100. LIGO/Virgo S200128d: Upper limits from CALET observations

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