Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. 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"

23690 results found.

  1. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  2. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  3. GRB 241127A: Swift detection of a burst with an optical counterpart
  4. Swift GRB241127.91: Global MASTER-Net OT detection
  5. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  6. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  7. EP241126a: Optical Upper limits with Kinder observations
  8. EP241126a: EP-FXT follow-up observation update
  9. EP241126a: GSP detects optical counterpart
  10. EP241126a: TRT optical counterpart detection
  11. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  12. EP241126a: EP detection of a fast X-ray transient
  13. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  14. GRB 241113B: EP-FXT afterglow detection
  15. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  16. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  17. Konus-Wind detection of GRB 241115D / EP 241115a
  18. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  19. GRB 241026A: radio detection with the VLA
  20. EP241125a: Optical upper limit with Kinder observations
  21. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  22. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  23. GRB 241120A: GRBAlpha detection
  24. GRB 241113B: SVOM/VT optical afterglow observations
  25. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  26. Konus-Wind detection of GRB 241117A
  27. IPN triangulation of GRB 241117A
  28. Konus-Wind detection of GRB 241120A
  29. GRB241120A: OHP/T193 optical observations
  30. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  31. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  32. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  33. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  34. EP241119a: Optical upper limits with Kinder observations
  35. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  36. EP241119a : J-band observations with WINTER
  37. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 241115A: Swift-XRT afterglow detection
  39. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  40. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  41. GRB 241113B: Mephisto upper limits
  42. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  43. The EP-WXT trigger 01709120856 is likely a flaring star
  44. GRB 241115A: Fermi GBM Observation
  45. EP241115a: EP detection of a fast X-ray transient
  46. EP241113a: No Detection in Fermi-GBM Observations
  47. Swift GRB 241115A: Global MASTER-Net observations report
  48. GRB 241115A: Swift detection of a burst
  49. GRB 241113B: KAIT Optical Afterglow Candidate
  50. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  51. GRB 241113A: Swift-BAT refined analysis
  52. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  53. GRB 241113B: J-band upper limit from WINTER
  54. GRB 241113A: J-band observations with WINTER
  55. EP241113a : J-band observations with WINTER
  56. GRB 241030A: LCO optical observation
  57. GRB 241113B: Swift-XRT observations
  58. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  59. GRB 241113A: KAIT optical observations
  60. EP241113b: Global MASTER-Net observations report
  61. EP241113b/GRB 241113B: EP detection of GRB 241113B
  62. Fermi-LAT gamma-ray observations of IceCube-241113A
  63. EP241113a: EP on-board trigger and autonomous follow-up observation
  64. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  65. GRB 241113A: Swift-XRT refined Analysis
  66. GRB 241113A: Swift/UVOT Detection
  67. GRB 241113A: REM detection of the optical/NIR afterglow
  68. Konus-Wind detection of GRB 241107A (short/hard)
  69. GRB 241113A: LCO optical observations
  70. GRB 241112B: GMG Optical Upper Limit
  71. GRB241113A: LCOGT (40-cm) optical counterpart detection
  72. GRB 241113A: Swift detection of a burst with an optical counterpart
  73. GRB 241112B: Swift-XRT afterglow detection
  74. GRB 241112B: SVOM/VT afterglow detection
  75. GRB 241112B: Mephisto optical upper limits
  76. GRB 241112B: GOTO optical upper limits
  77. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  78. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  79. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  80. IPN triangulation of GRB 241107A (short/hard)
  81. GRB 241025C: VZLUSAT-2 detection
  82. GRB 241025A: VZLUSAT-2 detection
  83. GRB 241018A: cubesat Avion detection
  84. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  85. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  86. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  87. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  88. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  89. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  90. EP241109a: confirmation of a stellar flare by BOOTES-7
  91. GRB 241108A: Swift-XRT observations
  92. EP241107a: KAIT optical observations
  93. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  94. EP241107a: Kinder optical follow-up observations
  95. GRB 241025A: radio detection with the VLA
  96. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  97. EP241107a: GSP detects optical counterpart
  98. EP241107a: OHP/T193 photometric and spectroscopic observations
  99. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  100. GRB 241105A: Swift/UVOT 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