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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"

45786 results found.

  1. GRB 240808A: SVOM/GRM observation
  2. GRB 240807A: SVOM/GRM observation
  3. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  4. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  5. EP240807a: STEP/T80S optical limits
  6. GRB 240807B: AstroSat CZTI detection of a short burst
  7. IceCube Alert 240808.27: Global MASTER-Net observations report
  8. EP EP240807a: Global MASTER-Net observations report
  9. EP EP240806a: Global MASTER-Net observations report
  10. IceCube-240808A - IceCube observation of a high-energy neutrino candidate track-like event
  11. GRB 240801A: GRBAlpha detection
  12. GRB 240807B: Fermi GBM Final Localization
  13. GRB 240710B: VZLUSAT-2 detection
  14. GRB 240805A: ATCA Radio Upper Limits
  15. Fermi trigger No 744761058: Global MASTER-Net observations report
  16. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  17. S240807h: Identification of a GW compact binary merger candidate
  18. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  19. EP240802a/GRB240802A: KAIT optical upper limit
  20. GRB 240720B: VZLUSAT-2 detection
  21. GRB 240710A: VZLUSAT-2 detection
  22. EP240806A: Liverpool Telescope optical follow-up observations
  23. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  24. GRB 240807A: Fermi GBM Final Localization
  25. EP240807a: EP-WXT detection of a fast X-ray transient
  26. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  27. GRB 240805B: GIT optical upper limit
  28. EP240806a: KAIT optical observations
  29. GRB 240805B: Swift-BAT refined analysis
  30. GRB 240805A: Swift-BAT refined analysis
  31. Fermi trigger No 744629911: Global MASTER-Net observations report
  32. EP240804a (GRB 240804B): NOT optical observations
  33. EP240806a: LCOGT optical counterpart detection
  34. Konus-Wind detection of GRB 240802A (EP240802a)
  35. Improved IPN triangulation of GRB 240802A / EP 240802a
  36. Konus-Wind detection of GRB 240805A
  37. GRB 240805B Bassano Bresciano Observatory upper limit
  38. GRB240805A: Fermi GBM Observation
  39. GRB 240805B: JinShan optical afterglow detection
  40. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  41. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  42. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  43. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  44. EP240806a: EP-FXT detection of the X-ray emission
  45. GRB 240626B: VZLUSAT-2 detection
  46. GRB 240624B: VZLUSAT-2 detection
  47. GRB 240619C: VZLUSAT-2 detection
  48. EP 240806A: LCO optical observations
  49. EP240806a: GSP optical counterpart detection
  50. EP240806a: EP-WXT detection of a fast X-ray transient
  51. GRB 240805B: Optical detection with 1.6m Mephisto
  52. EP240804a: BOOTES-6/DPRT optical detection
  53. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  54. GRB 240805B: Swift-XRT refined Analysis
  55. Fermi trigger No 744544656: Global MASTER-Net observations report
  56. GRB 240805B: Swift/UVOT Upper Limits
  57. GRB 240805A: Swift/UVOT Upper Limits
  58. GRB 240805B: BTA optical afterglow candidate
  59. GRB 240805A: SVOM/GRM observation
  60. GRB 240805B: Enhanced Swift-XRT position
  61. GRB 240805B: LCOGT Optical Upper Limits
  62. Swift GRB 240805B: Global MASTER-Net observations report
  63. GRB 240805B: JinShan optical upper limits
  64. EP240801a: BTA BVRI photometry
  65. Fermi GRB 240805A: Global MASTER-Net observations report
  66. Swift GRB 240805A: Global MASTER-Net observations report
  67. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  68. GRB 240805A: Swift-XRT refined Analysis
  69. EP240804a: GSP detects optical candidate counterpart
  70. GRB 240805B: Swift detection of a burst
  71. GRB 240805A: Fermi-LAT detection
  72. GRB 240805A: INTEGRAL spectral analysis
  73. EP240801a: Continued optical observations at ZTSh (CraO)
  74. EP240804a: VLT/X-shooter spectroscopic redshift
  75. EP240804a: LCOGT optical counterpart detection
  76. GRB 240805A: A long GRB detected by INTEGRAL
  77. EP-WXT trigger 00109017646 is not a real source
  78. EP240804a: NOT optical counterpart detection
  79. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  80. EP240802a: correction of EP-WXT trigger time in GCN 37019
  81. GRB 240805A: Swift detection of a burst
  82. GRB 240805A: Fermi GBM Final Real-time Localization
  83. Fermi GRB 240804A: Global MASTER-Net observations report
  84. EP240802a: Montarrenti Observatory optical upper limit
  85. GRB 240804A: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 744459130: Global MASTER-Net observations report
  87. IPN triangulation of GRB 240802A / EP 240802a
  88. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  89. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  90. EP240802A: Bassano Bresciano Observatory upper limit
  91. GRB 240802A: SVOM/GRM observation
  92. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  93. Fermi trigger No 744278264: Global MASTER-Net observations report
  94. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  95. GRB 240802A: AstroSat CZTI detection of a long burst
  96. EP240801a: further SAO RAS optical observations
  97. EP240801a: optical observations at CrAO and AbAO
  98. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  99. EP240801a: Leavitt Observatory optical observations
  100. EP240801a: GTC spectroscopy and absorption redshift

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