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"

32703 results found.

  1. Swift GRB 241229B: Global MASTER-Net observations report
  2. GRB 241229A: GOTO optical upper limits
  3. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  4. GRB 241228A: NOT optical upper limits
  5. GRB 241228B: LCO optical observation
  6. GRB 241228A: Swift-BAT refined analysis
  7. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  8. Fermi GRB 241228B: Global MASTER-Net observations report
  9. GRB 241228A: Fermi GBM Observation
  10. GRB241228B: GROWTH-India Telescope optical observations
  11. Swift GRB 241228A: Global MASTER-Net observations report
  12. GRB 241228B: LCOGT photometry of the likely optical counterpart GOTO24jmz
  13. GRB 241228B: GOTO24jmz optical follow-up observations
  14. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  15. GRB 241228A: GROWTH-India telescope optical upper limit
  16. GRB 241228B: Swift ToO observations
  17. GRB 241228B: TRT optical counterpart confirmation
  18. GRB 241228A: Swift/UVOT Upper Limits
  19. GRB 241228B: GOTO possible optical counterpart candidate
  20. IceCube-241224A: Upper limits from a search for additional neutrino events in IceCube
  21. GRB 241223A: GRBAlpha detection
  22. GRB 241212A: VZLUSAT-2 detection
  23. GRB 241217A/EP241217b: continued SOAR observations
  24. Fermi GRB 241226A: Global MASTER-Net observations report
  25. EP241223a: Mondy AZT-33IK optical observations
  26. GRB 241029A: LCO optical observation
  27. GRB 241223A: Swift-XRT observations
  28. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  29. GRB 241029A: AbAO AS-32 optical observations
  30. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  31. EP241223a
  32. EP241223a: Global MASTER-Net observations report
  33. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  34. GRB241113A: 7DT Optical upper limits
  35. Fermi GRB 241223A: Global MASTER-Net observations report
  36. GRB 241223A: GOTO optical observations summary
  37. GRB 241105A: JWST photometric observations of the host galaxy
  38. GRB 241223A: Swift ToO observations
  39. EP241217a: e-MERLIN radio observations
  40. GRB 241217A / EP241217b: Non-detection in ATCA Radio Follow-up Observations
  41. GRB 241209B: host galaxy detection and GTC/OSIRIS+ spectroscopy
  42. Fermi GRB 241221A: Global MASTER-Net observations report
  43. GRB 241217A/EP241217b: SOAR afterglow detection
  44. EP241217a: Liverpool Telescope optical upper limit
  45. EP241021a: VLA radio detection
  46. GRB 241218A: Mondy AZT-33IK optical upper limit
  47. EP241217a : Leavitt Observatory optical upper limit
  48. GRB 241217A/EP241217b: tentative VLT spectroscopic redshift z=1.879
  49. EP241217a: 1.6m Mephisto multi-band optical observations
  50. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  51. GRB 241218A: Swift/UVOT Upper Limits
  52. EP241217a: optical upper limit with the Liverpool Telescope
  53. GRB 241209B: EP-FXT afterglow detection
  54. Konus-Wind detection of GRB 241204A (short/hard)
  55. GRB 241218A: NOT optical upper limits
  56. GRB 241218A: Swift-BAT refined analysis
  57. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  58. EP 241217a: NIR detection with P200/WIRC
  59. EP 241217a: Possible J-band detection with WINTER
  60. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  61. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  62. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  63. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  64. GRB 241217A / EP241217b: NOT optical upper limits
  65. GRB 241218A: REM optical upper limit
  66. GRB 241217A/EP241217b: REM optical/NIR upper limits
  67. EP241217a: REM optical/NIR upper limits
  68. GRB 241218a: Liverpool Telescope optical follow-up
  69. GRB 241217a: Liverpool Telescope optical follow-up
  70. EP241217a: Liverpool Telescope optical follow-up
  71. EP241217a: NOT optical observations
  72. EP241217a: GROWTH-India Telescope optical observations
  73. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  74. EP241119a: 7DT Optical upper limits
  75. EP241217b: Global MASTER-Net observations report
  76. GRB 241209A: ATCA radio follow-up observations
  77. EP241217a: Xinglong optical follow-up observations
  78. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  79. GRB 241218A: LCOGT Optical Upper Limit
  80. EP241217a: Global MASTER-Net observations report
  81. GRB 241217A: GMG Optical Upper Limit
  82. GRB 241217A : SVOM/VT optical afterglow detection
  83. GRB 241217A: LCO optical upper limit
  84. GRB 241217A: GRANDMA/TAROT optical upperlimits
  85. EP241217a: Swift-XRT Detection
  86. EP241217A: Non-detection from Fermi-GBM Observations
  87. EP241217a: Gemini-North spectroscopic redshift z = 4.59
  88. EP241217a: Kinder optical follow-up observations
  89. GRB 241214A: GRBAlpha detection
  90. GRB 241213A (EP241213a): GRBAlpha detection
  91. GRB 241209D: GRBAlpha detection
  92. EP241217A: LCO optical observations
  93. EP241217a: Gemini-North detection of the likely optical counterpart
  94. EP241107a: VLA Radio Observation
  95. GRB 241213A: Swift-BAT refined analysis
  96. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  97. Konus-Wind detection of GRB 241213A (EP 241213a)
  98. GRB 241215A: Mondy AZT-33IK optical observations
  99. GRB 241215A: Nanshan/HMT optical upper limit
  100. GRB 241215A: Montarrenti Observatory optical upper limit

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