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"

27297 results found.

  1. LIGO/Virgo S190425z - ePESSTO+ spectrum of PS19qp shows red featureless source at z=0.037
  2. LIGO/Virgo S190425z - ePESSTO+ NTT spectrum of candidate PS19qo
  3. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  4. LIGO/Virgo S190425z - ePESSTO+ NTT observations
  5. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  6. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  7. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  8. LIGO/Virgo S190425z: Palomar Gattini-IR wide-field infrared follow-up
  9. LIGO/Virgo S190425z: Fermi GBM Observations
  10. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  11. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  12. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  13. LIGO/Virgo S190425z: MAXI/GSC Observations
  14. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  15. LIGO/VirgoS190425z: HAWC follow-up
  16. LIGO/Virgo S190425z: SAGUARO follow-up observations
  17. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  18. LIGO/Virgo S190425z: INTEGRAL prompt observation
  19. LIGO/Virgo S190425z Global MASTER-Net observations report
  20. Fermi GRB190425.09 Global MASTER-Net observations report
  21. GRB 190424A: Swift-BAT refined analysis
  22. GRB 190424A: Swift detection of a burst
  23. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  24. GRB 190422A: Fermi GBM detection
  25. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  26. GRB 190422A: Swift/UVOT Upper Limits
  27. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  28. GRB 190422A: Swift-BAT refined analysis
  29. GRB 190422A: Swift-XRT refined Analysis
  30. LIGO/Virgo S190421ar: MAXI/GSC Observations
  31. Swift GRB190422.96 Global MASTER-Net observations report
  32. Fermi GRB190422.96 Global MASTER-Net observations report
  33. Fermi GRB190422.67 Global MASTER-Net observations report
  34. GRB 190422A: Swift detection of a burst
  35. LIGO/Virgo S190421ar: Fermi-GBM Observations
  36. LIGO/Virgo S190421ar Global MASTER-Net observations report
  37. LIGO/Virgo S190421ar: HAWC follow-up
  38. Fermi GRB190420.98 Global MASTER-Net observations report
  39. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  40. Fermi GRB190419.41 Global MASTER-Net observations report
  41. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  42. Fermi Trigger 577360542 / GRB 190419414 / GRB190419A: BALROG localization
  43. Fermi GRB190418.92 Global MASTER-Net observations report
  44. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  45. IPN Triangulation of GRB 190415A
  46. Fermi GRB190417.46 Global MASTER-Net observations report
  47. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  48. GRB 190415A: Insight-HXMT/HE detection
  49. Fermi Trigger 576994194 / GRB 190415173 / : BALROG localization
  50. Fermi GRB190415.17 Global MASTER-Net observations report
  51. GRB 190411A: Insight-HXMT/HE detection
  52. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  53. LIGO/Virgo S190412m: Swift/BAT data search
  54. LIGO/Virgo S190412m: Fermi-GBM Observations
  55. LIGO/Virgo S190412m: MAXI/GSC Observations
  56. LIGO/Virgo S190405ar: Retraction of a GW binary merger candidate
  57. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  58. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  59. LIGO/Virgo S190412m: HAWC follow-up
  60. LIGO/Virgo S190412m: MASTER early alert observation
  61. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  62. IPN triangulation of GRB 190409B (short)
  63. GRB 190409A: ground analysis reveals a likely spurious event
  64. LIGO/Virgo S190408an: MAXI/GSC Observations
  65. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  66. LIGO/Virgo S190408an: CALET Observations
  67. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  68. Konus-Wind observation of GRB 190404B
  69. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  70. GRB 190409A: Swift detection of a possible burst
  71. LIGO-Virgo S190408an: further AGILE GRID observations after T0
  72. LIGO/Virgo S190408an: SAGUARO follow-up observations
  73. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  74. LIGO/Virgo S190408an: Swift/BAT data search
  75. LIGO-Virgo S190408an: AGILE GRID observations
  76. LIGO-Virgo S190408an: HAWC follow-up
  77. LIGO/Virgo S190408an: Fermi GBM Observation
  78. Fermi Gamma-ray Burst Monitor trigger 576420743/190408536 is not a GRB
  79. Fermi Trigger 576356086 / GRB 190407788 / : BALROG localization
  80. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  81. Fermi Trigger 576346051 / GRB 190407672 / GRB 190407A: BALROG localization
  82. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  83. Swift GRB 190331B: Further Swift-XRT observations
  84. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  85. Trigger 896552: Swift detection of PSR B1055-52
  86. GRB 190401A: Insight-HXMT/HE detection
  87. GRB 190331C: Insight-HXMT/HE detection
  88. GRB 190331A: Insight-HXMT/HE detection
  89. GRB 190330A: Insight-HXMT/HE detection
  90. GRB 190329A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 190331A: Fermi GBM detection
  92. GRB 190331A, Swift-BAT refined analysis
  93. IPN Triangulation of GRB 190329A (long/bright)
  94. GRB 190331A: Swift detection of a burst
  95. Fermi Trigger 575656777 / GRB 190330694 / GRB 190330A: BALROG localization
  96. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  97. GRB 190326A: 2.2m CAHA telescope optical limit
  98. Swift Trigger 895503 is not a GRB
  99. Swift Trigger 895479: Detection of GRO J2058+42
  100. GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR

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