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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32494 results found.

  1. GRB240805A: Fermi GBM Observation
  2. GRB 240805B: JinShan optical afterglow detection
  3. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  4. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  5. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  6. EP240806a: EP-FXT detection of the X-ray emission
  7. GRB 240624B: VZLUSAT-2 detection
  8. GRB 240619C: VZLUSAT-2 detection
  9. EP 240806A: LCO optical observations
  10. GRB 240805B: Optical detection with 1.6m Mephisto
  11. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  12. GRB 240805B: Swift/UVOT Upper Limits
  13. GRB 240805A: Swift/UVOT Upper Limits
  14. GRB 240805B: BTA optical afterglow candidate
  15. GRB 240805A: SVOM/GRM observation
  16. GRB 240805B: LCOGT Optical Upper Limits
  17. Swift GRB 240805B: Global MASTER-Net observations report
  18. GRB 240805B: JinShan optical upper limits
  19. EP240801a: BTA BVRI photometry
  20. Fermi GRB 240805A: Global MASTER-Net observations report
  21. Swift GRB 240805A: Global MASTER-Net observations report
  22. GRB 240805A: Fermi-LAT detection
  23. GRB 240805A: INTEGRAL spectral analysis
  24. EP240801a: Continued optical observations at ZTSh (CraO)
  25. EP240804a: VLT/X-shooter spectroscopic redshift
  26. EP240804a: LCOGT optical counterpart detection
  27. GRB 240805A: A long GRB detected by INTEGRAL
  28. EP240804a: NOT optical counterpart detection
  29. EP240802a: correction of EP-WXT trigger time in GCN 37019
  30. Fermi GRB 240804A: Global MASTER-Net observations report
  31. EP240802a: Montarrenti Observatory optical upper limit
  32. IPN triangulation of GRB 240802A / EP 240802a
  33. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  34. EP240802A: Bassano Bresciano Observatory upper limit
  35. GRB 240802A: SVOM/GRM observation
  36. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  37. EP240801a: further SAO RAS optical observations
  38. EP240801a: optical observations at CrAO and AbAO
  39. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  40. EP240801a: Leavitt Observatory optical observations
  41. EP240801a: GTC spectroscopy and absorption redshift
  42. EP240801a: SAO RAS optical observations
  43. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  44. EP240801a: JinShan optical observations
  45. GRB 240727C: SVOM/GRM observation
  46. EP240801a: NOT optical observations
  47. EP240801a: follow-up observation with LCOGT
  48. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  49. GRB 240730A: Swift-BAT refined analysis
  50. EP240801a: GSP follow-up observations of the candidate counterpart
  51. EP240801a: Kinder follow-up observations of the candidate counterpart
  52. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  53. EP240801a: KAIT optical counterpart observations
  54. EP240801a: GMG observation
  55. EP240801a: TRT optical counterpart detection
  56. Fermi GRB 240801A: Global MASTER-Net observations report
  57. GRB 240731A: Fermi GBM Final Localization
  58. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  59. Fermi GRB 240730B: Global MASTER-Net observations report
  60. Swift GRB 240730A: Global MASTER-Net observations report
  61. GRB 240715A: Swift-XRT afterglow detection
  62. GRB 240730A: KAIT Optical Upper Limit
  63. GRB 240727C: GRBAlpha detection
  64. GRB 240730A: Swift/UVOT Upper Limits
  65. GRB 240727A: Swift-BAT refined analysis
  66. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  67. GRB 240727A: observations of optical counterpart.
  68. GRB 240727B: Swift-XRT observations
  69. Fermi GRB 240727A: Global MASTER-Net observations report
  70. GRB 240727A: Swift/UVOT detection
  71. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  72. GRB 240727A: NOT optical observation
  73. GRB 240727A: JinShan optical upper limits
  74. GRB 240727A Bassano Bresciano Observatory upper limit
  75. GRB 240727D: Correction to the GRB name in GCN 36958
  76. GRB 240720B: GRBAlpha detection
  77. GRB 240718A: GRBAlpha detection
  78. GRB 240627A: GRBAlpha detection
  79. Fermi GRB 240726A: Global MASTER-Net observations report
  80. GRB 240727B: Fermi GBM Observation
  81. GRB240529A: VIRT optical transient detection
  82. GRB 240727B: Swift ToO observations
  83. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  84. GRB 240726A: SVOM/GRM observation
  85. GRB240727A: Skynet Optical Afterglow Observations
  86. GRB 240727A: TRT optical afterglow detection
  87. GRB 240727A: KAIT Optical Afterglow Candidate
  88. GRB 240726A: AstroSat CZTI detection of a short burst
  89. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  90. Fermi-LAT gamma-ray observations of IceCube-240725A
  91. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  92. GRB 240720A: Swift-BAT refined analysis
  93. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  94. Fermi-LAT gamma-ray observations of IceCube-240721A
  95. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  96. GRB 240720B: SVOM/GRM observation
  97. Fermi GRB 240720A: Global MASTER-Net observations report
  98. GRB 240720A: AstroSat CZTI detection
  99. GRB 240720A: Fermi GBM observation
  100. Konus-Wind detection of GRB 240718A

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