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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"

32692 results found.

  1. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  2. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  3. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  4. EP240806a: EP-FXT detection of the X-ray emission
  5. GRB 240624B: VZLUSAT-2 detection
  6. GRB 240619C: VZLUSAT-2 detection
  7. EP 240806A: LCO optical observations
  8. GRB 240805B: Optical detection with 1.6m Mephisto
  9. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  10. GRB 240805B: Swift/UVOT Upper Limits
  11. GRB 240805A: Swift/UVOT Upper Limits
  12. GRB 240805B: BTA optical afterglow candidate
  13. GRB 240805A: SVOM/GRM observation
  14. GRB 240805B: LCOGT Optical Upper Limits
  15. Swift GRB 240805B: Global MASTER-Net observations report
  16. GRB 240805B: JinShan optical upper limits
  17. EP240801a: BTA BVRI photometry
  18. Fermi GRB 240805A: Global MASTER-Net observations report
  19. Swift GRB 240805A: Global MASTER-Net observations report
  20. GRB 240805A: Fermi-LAT detection
  21. GRB 240805A: INTEGRAL spectral analysis
  22. EP240801a: Continued optical observations at ZTSh (CraO)
  23. EP240804a: VLT/X-shooter spectroscopic redshift
  24. EP240804a: LCOGT optical counterpart detection
  25. GRB 240805A: A long GRB detected by INTEGRAL
  26. EP240804a: NOT optical counterpart detection
  27. EP240802a: correction of EP-WXT trigger time in GCN 37019
  28. Fermi GRB 240804A: Global MASTER-Net observations report
  29. EP240802a: Montarrenti Observatory optical upper limit
  30. IPN triangulation of GRB 240802A / EP 240802a
  31. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  32. EP240802A: Bassano Bresciano Observatory upper limit
  33. GRB 240802A: SVOM/GRM observation
  34. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  35. EP240801a: further SAO RAS optical observations
  36. EP240801a: optical observations at CrAO and AbAO
  37. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  38. EP240801a: Leavitt Observatory optical observations
  39. EP240801a: GTC spectroscopy and absorption redshift
  40. EP240801a: SAO RAS optical observations
  41. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  42. EP240801a: JinShan optical observations
  43. GRB 240727C: SVOM/GRM observation
  44. EP240801a: NOT optical observations
  45. EP240801a: follow-up observation with LCOGT
  46. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  47. GRB 240730A: Swift-BAT refined analysis
  48. EP240801a: GSP follow-up observations of the candidate counterpart
  49. EP240801a: Kinder follow-up observations of the candidate counterpart
  50. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  51. EP240801a: KAIT optical counterpart observations
  52. EP240801a: GMG observation
  53. EP240801a: TRT optical counterpart detection
  54. Fermi GRB 240801A: Global MASTER-Net observations report
  55. GRB 240731A: Fermi GBM Final Localization
  56. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  57. Fermi GRB 240730B: Global MASTER-Net observations report
  58. Swift GRB 240730A: Global MASTER-Net observations report
  59. GRB 240715A: Swift-XRT afterglow detection
  60. GRB 240730A: KAIT Optical Upper Limit
  61. GRB 240727C: GRBAlpha detection
  62. GRB 240730A: Swift/UVOT Upper Limits
  63. GRB 240727A: Swift-BAT refined analysis
  64. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  65. GRB 240727A: observations of optical counterpart.
  66. GRB 240727B: Swift-XRT observations
  67. Fermi GRB 240727A: Global MASTER-Net observations report
  68. GRB 240727A: Swift/UVOT detection
  69. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  70. GRB 240727A: NOT optical observation
  71. GRB 240727A: JinShan optical upper limits
  72. GRB 240727A Bassano Bresciano Observatory upper limit
  73. GRB 240727D: Correction to the GRB name in GCN 36958
  74. GRB 240720B: GRBAlpha detection
  75. GRB 240718A: GRBAlpha detection
  76. GRB 240627A: GRBAlpha detection
  77. Fermi GRB 240726A: Global MASTER-Net observations report
  78. GRB 240727B: Fermi GBM Observation
  79. GRB240529A: VIRT optical transient detection
  80. GRB 240727B: Swift ToO observations
  81. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  82. GRB 240726A: SVOM/GRM observation
  83. GRB240727A: Skynet Optical Afterglow Observations
  84. GRB 240727A: TRT optical afterglow detection
  85. GRB 240727A: KAIT Optical Afterglow Candidate
  86. GRB 240726A: AstroSat CZTI detection of a short burst
  87. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  88. Fermi-LAT gamma-ray observations of IceCube-240725A
  89. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  90. GRB 240720A: Swift-BAT refined analysis
  91. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  92. Fermi-LAT gamma-ray observations of IceCube-240721A
  93. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  94. GRB 240720B: SVOM/GRM observation
  95. Fermi GRB 240720A: Global MASTER-Net observations report
  96. GRB 240720A: AstroSat CZTI detection
  97. GRB 240720A: Fermi GBM observation
  98. Konus-Wind detection of GRB 240718A
  99. GRB 240713A: SVOM/GRM observation
  100. Fermi GRB 240718A: Global MASTER-Net observations report

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