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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"

74 results found.

  1. Fermi GRB 261030B: Global MASTER-Net observations report
  2. GRB 260715A: cubesat Avion detection
  3. GRB 260709A: cubesat Avion detection
  4. GRB 260708A: cubesat Avion detection
  5. The EP-WXT trigger 01709266147 is likely a flaring star
  6. Fermi GRB 260525A: Global MASTER-Net observations report
  7. Fermi GRB 260223A: Global MASTER-Net observations report
  8. Trigger 1442421: Swift detection of HMXB 1A 1118-61
  9. Swift trigger on the HMXB 1A 1118-61
  10. Swift triggered on the HMXB 1A 1118-61
  11. Fermi GRB 260111A: Global MASTER-Net observations report
  12. Fermi GRB 251214A: Global MASTER-Net observations report
  13. EP250905b: Global MASTER-Net observations report
  14. GRB 250819A: AstroSat CZTI detection
  15. GRB 250702A: Fermi GBM Detection
  16. GRB 250507B: AstroSat CZTI detection
  17. EP250407a: Global MASTER-Net observations report
  18. Fermi GRB 250210A: Global MASTER-Net observations report
  19. GRB 250202B: AstroSat CZTI detection of a bright long GRB
  20. GRB 250101A: SVOM/C-GFT early optical observations
  21. Fermi trigger No 751861204: Global MASTER-Net observations report
  22. Fermi trigger No 751554401: Global MASTER-Net observations report
  23. GRB 241001A: Swift-XRT observations
  24. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  25. GRB 240726B: AstroSat CZTI detection of a short burst
  26. LIGO/Virgo/KAGRA S240422ed: Early X-ray Upper Limits from EP-WXT for the LVK Sky Localization Region
  27. GRB 240225B: Glowbug gamma-ray detection
  28. Fermi GRB 230818A: Global MASTER-Net observations report
  29. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  30. GRB 221006A: Swift-XRT observations
  31. Fermi GRB 220523A: Global MASTER-Net observations report
  32. GRB 220408A: Swift/UVOT Detection
  33. Konus-Wind detection of GRB 220124A
  34. GRB 220117B: Swift/UVOT Upper Limits
  35. Fermi GRB 211031A: Global MASTER-Net observations report
  36. GRB 210926A: AstroSat CZTI detection
  37. Fermi trigger No 647271699: Global MASTER-Net observations report
  38. Integral GRB210707.02: Global MASTER-Net observations report
  39. GRB 210330A: AstroSat CZTI detection
  40. GRB 210307A: Swift-BAT refined analysis
  41. GRB 210212A: Swift/UVOT Upper Limits
  42. GRB 201229A: Swift-XRT refined Analysis
  43. Trigger 1007266: Swift detection of 1A 0535+262
  44. Swift Trigger 1006917 is Be/X-ray binary pulsar 1A 0535+262
  45. GRB 200917A: Swift/UVOT Upper Limits
  46. Fermi GRB 200524A: Global MASTER-Net observations report
  47. GRB 200205A: MAXI/GSC detection
  48. GRB 200109A: Swift-XRT refined Analysis
  49. GRB 190919B: Swift/UVOT Upper Limits
  50. GRB 190519A: Swift/UVOT Upper Limits
  51. GRB 180705A: Swift-BAT refined analysis
  52. GRB 180418A: TAROT La Silla observatory early optical observations
  53. Konus-Wind observation of GRB 171227A
  54. GRB 170808B: Fermi GBM observation
  55. GRB 170419B, Swift-BAT refined analysis
  56. Konus-Wind observation of GRB 151229B
  57. GRB 140626A: Swift/UVOT Upper Limits
  58. GRB 130418A: Swift-XRT refined Analysis
  59. GRB 120624B: Further analysis of the HAWKI observations
  60. GRB 120422A: A Swift/UVOT Detection
  61. IPN Triangulation of GRB 120323A (short/very intense)
  62. IBAS trigger n. 6138 is not a GRB
  63. Swift detection of outburst from the SFXT IGR J18410-0535
  64. GRB100219A Akeno and Okayama MITSuME Optical Observation
  65. GRB 091221: Fermi GBM Observation
  66. GRB 091221: Swift detection of a burst
  67. Konus-Wind observation of bright short GRB 090227B
  68. GRB 090113: Swift detection of a burst
  69. Swift triggered on the HMXB 1A 1118-61
  70. GRB 080325: Swift/UVOT Upper Limits
  71. VLT/UVES redshift of GRB 080319B from FeII fine-structure lines
  72. GRB 071003: Keck HIRES spectroscopy
  73. GRB 070306 Swift/UVOT refined analysis
  74. GRB 050509B: Swift/XRT refined analysis

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