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"

24511 results found.

  1. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  2. GRB 241002C : MITSuME Akeno optical upper limits
  3. LIGO/Virgo/KAGRA S240925n: Updated Sky localization
  4. NuEm-240926A: Upper limits from a search for coincident neutrino events in IceCube
  5. GRB241001A: REM optical/NIR upper limits
  6. LIGO/Virgo/KAGRA S241002e: Updated Sky localization
  7. GRB 241002A: LCOGT Optical Upper Limits
  8. GRB 241001A: VLT/X-shooter redshift
  9. GRB 241002B: GOTO optical counterpart candidate
  10. EP trigger ID 01709064214: GOTO confirms detection as a flare star
  11. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  12. GRB 240929A: Liverpool Telescope prompt followup observations
  13. Fermi GRB 241002B: Global MASTER-Net observations report
  14. GRB 241001A: Swift-XRT observations
  15. GRB 241002B: Fermi GBM Final Real-time Localization
  16. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  17. GRB 241002A: Swift detection of a burst
  18. LIGO/Virgo/KAGRA S240930du: Updated Sky localization
  19. GRB 240930B: Fermi GBM Observation
  20. GRB 240930B: GRBAlpha detection
  21. GRB 240929A: GRBAlpha detection
  22. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  23. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  24. EP240930a: EP-FXT follow-up observation update
  25. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  26. EP240930a: GOTO optical upper limits
  27. GRB 240929A: SVOM/GRM observation
  28. EP EP240930a: Global MASTER-Net observations report
  29. EP240930a: EP-WXT detection of a fast X-ray transient
  30. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  31. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  32. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  33. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  34. AMON NuEM 240926A: Swift XRT Follow-up
  35. Fermi GRB 240930B: Global MASTER-Net observations report
  36. GRB 240930B: Fermi GBM Final Real-time Localization
  37. IPN triangulation of GRB 240926A
  38. GRB 240825A: LBT optical observations
  39. GRB 240928A: SVOM/GRM observation
  40. Fermi GRB 240930A: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  42. GRB 240930A: Fermi GBM Final Real-time Localization
  43. Fermi trigger No 749339671: Global MASTER-Net observations report
  44. GRB 240929A long GRB detected by INTEGRAL
  45. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  46. Fermi GRB 240929A: Global MASTER-Net observations report
  47. GRB 240929A: Fermi GBM Final Real-time Localization
  48. Integral GRB240929.83: Global MASTER-Net observations report
  49. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  50. Konus-Wind detection of GRB 240912A
  51. Swift Trigger 1256950 is probably not a GRB
  52. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  53. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  54. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  55. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  56. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  57. GRB 240926A: SVOM/GRM observation
  58. EP trigger ID 01709061302: the X-ray transient is likely a stellar flare event
  59. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240926A
  60. Konus-Wind detection of GRB 240905B
  61. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  62. EP240919a / GRB 240919A: SVOM/VT upper limit
  63. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  64. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  65. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  66. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  67. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  68. Konus-Wind detection of GRB 240918B
  69. IPN triangulation of GRB 240918B
  70. GRB 240905B: VZLUSAT-2 detection
  71. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  72. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  73. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  74. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  75. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  76. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  77. EP trigger ID 01709059262: correction to the observation start time and source localization
  78. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  79. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  80. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  81. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  82. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  83. EP240913a/GRB 240913C: 1.6m Mephisto observations
  84. EP240918a: SVOM/VT upper limit
  85. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  86. EP240919a / GRB 240919A: REM optical and NIR upper limits
  87. GRB 240919A / EP240919a: SVOM/GRM observation
  88. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  89. EP EP240919a: Global MASTER-Net observations report
  90. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  91. EP240919a: NOT and Gemini optical observations
  92. EP240919a: GOTO optical upper limits
  93. EP240919a is likely a GRB event
  94. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  95. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  96. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  97. GRB 240918B: Fermi GBM Detection
  98. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  99. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  100. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate

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