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"

41700 results found.

  1. GRB 150910A: Chuguev observatory optical observations
  2. GRB 150911A: MITSuME Okayama upper limits
  3. GRB 150910A: VLA Detection
  4. GRB 150910A: continued SAO RAS optical observations
  5. GRB150911A MITSuME Okayama Ks-band upper-limit
  6. GRB 150910A: TSHAO optical observations
  7. GRB 150911A: Swift detection of a burst
  8. GRB 150910A: NOT observations of the afterglow
  9. GRB 150910A: MITSuME Okayama Ks-band Observation
  10. GRB 150910A: GROND observation of the afterglow
  11. GRB 150910A: MITSuME Ishigakijima Optical Observation
  12. GRB 150910A: SAO RAS optical photometry
  13. GRB 150910A: Redshift from 10.4m GTC+OSIRIS
  14. GRB 150910A: Kast spectroscopy from 3m Shane telescope
  15. GRB 150910A: Swift-XRT refined Analysis
  16. GRB 150910A: Swift/UVOT Detection of a Brightening Afterglow
  17. GRB 150910A: Nanshan optical observations
  18. GRB 150910A: Swift-BAT refined analysis
  19. GRB 150910A: MITSuME Okayama Optical Observation
  20. GRB 150910A: LCOGT FTN afterglow observations
  21. GRB 150910A: KAIT Optical Afterglow Detection
  22. GRB 150910A: Swift detection of a burst with an optical afterglow
  23. Short GRB 150906B: proximity to NGC 3313 galaxy group
  24. Swift Trigger 654954 is not an astrophysical event
  25. Fermi GBM trigger 463422723/150908689 is not a GRB
  26. GRB 150907B: Swift-XRT refined Analysis
  27. Konus-Wind observation of GRB 150906B
  28. IPN Triangulation of GRB 150906B (short/intense)
  29. GRB 150907B: Swift-BAT refined analysis
  30. GRB150907A: Swift/UVOT observations
  31. GRB 150907B: MASTER-SAAO early optical observations
  32. GRB 150907B: GROND Upper Limits
  33. GRB 150907A: Swift-XRT observations
  34. GRB 150907B: Swift detection of a burst
  35. Fermi GBM trigger 150907763 is not a GRB
  36. GRB 150907A: Tiled Swift observations
  37. GRB 150907A: MAXI/GSC detection
  38. GRB 150906A: Fermi GBM detection
  39. GRB 150818A: TSHAO and SAO RAS optical observations
  40. GRB 150902A: Swift-XRT afterglow detection
  41. ANTARES neutrino detection: ANU 2.3m and Kepler K2 Observations of the Swift x-ray source
  42. ANTARES neutrino detection: CAHA photometry & spectroscopy of the Swift source
  43. ANTARES neutrino Alert150901.32 alert and Swift XRT counterpart: MASTER optical observations and new possible candidate
  44. ANTARES neutrino detection and Swift/XRT counterpart: GMG observation
  45. GRB 150902A: Swift/UVOT Upper Limits
  46. GRB 150902A: Swift-XRT observations
  47. ANTARES neutrino detection: Optical/NIR spectroscopy of the Swift/XRT counterpart candidate from NOT
  48. GRB 150831A: 9.8 GHz VLA upper limits
  49. GRB 150902A: MASTER-SAAO optical observations
  50. Konus-Wind observation of GRB 150902A
  51. GRB 150901A, Swift-BAT refined analysis
  52. ANTARES neutrino detection and possible Swift X-ray counterpart
  53. GRB 150902A: Swift ToO observations
  54. GRB 150902A: Fermi GBM detection
  55. GRB 150902A: Fermi-LAT detection
  56. GRB 150831B: Swift/UVOT Upper Limits
  57. Konus-Wind observation of GRB 150831A
  58. GRB 150901A: Swift detection of a burst
  59. GRB 150821A: Flattening in the UVOT light curve
  60. GRB 150831B: Swift-BAT refined analysis
  61. GRB 150831B: Swift-XRT refined Analysis
  62. GRB 150831B: MASTER-IAC early optical observations
  63. GRB 150831B: Fermi GBM detection
  64. GRB 150831A: GROND Upper Limits
  65. GRB 150831A: Swift/UVOT Upper Limits
  66. GRB 150831A: Swift-XRT refined Analysis
  67. GRB 150831B: Swift detection of a probable burst
  68. GRB 150831A: Swift-BAT refined analysis
  69. GRB 150818A: Spectroscopic confirmation of the SN from GTC
  70. GRB 150831A: optical upper limit ISON-SSO
  71. INTEGRAL detection of GRB 150831A
  72. GRB 150831A: Swift detection of a short burst
  73. Fermi GBM trigger 150829183 is not a GRB
  74. Fermi GBM trigger 150828520 is not a GRB
  75. Fermi GBM trigger 150827524 is not a GRB
  76. GRB 150818A: possible SN rise in light curve of Mondy observations
  77. Fermi GBM trigger 150826536 is not a GRB
  78. Konus-Wind observation of GRB 150824A
  79. IPN Triangulation of GRB 150824A
  80. GRB 150824A: Fermi GBM detection
  81. Konus-Wind observation of GRB 150821A
  82. GRB 150821A: LCOGT Siding Springs early observations
  83. Konus-Wind observation of GRB 150818A
  84. GRB 150821A: LCOGT Sutherland observations
  85. GRB 150821A, Swift-BAT refined analysis
  86. GRB 150821A: GROND afterglow observations
  87. GRB 150821A: Swift-XRT refined Analysis
  88. GRB 150819A: Mondy and TSHAO optical upper limits
  89. GRB 150821A: Swift/UVOT Detection
  90. GRB 150821A: Fermi GBM detection
  91. GRB 150818A: continued Mondy optical observations
  92. Swift Trigger 652824 is due to noise
  93. GRB 150821A: VLT/X-shooter redshift
  94. GRB 150821A: Swift detection of a burst with an optical afterglow
  95. Swift Trigger 652824: Is most likely a noise fluctuation in the direction of M31
  96. GRB 120729A: KAIT Optical Observations
  97. KAIT Optical Upper Limits for GRB 120422A, 120724A, 120803B, 120911A, and 120923A
  98. GRB 150818A: Mondy optical observations
  99. GRB150819A: NOT imaging
  100. Konus-Wind observation of GRB 150819B

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