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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.

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

42517 results found.

  1. GRB 250919A: Fermi GBM Final Real-time Localization
  2. GRB 250916A: KAIT optical observations
  3. GRB 250917B: VLT/HAWK-I near-infrared observations
  4. GRB 250916A: NuSTAR detection of the prompt emission
  5. GRB 250916A: further SAO RAS optical observations
  6. GRB 250912A: SVOM/ECLAIRs refined analysis
  7. GRB 250917B: Swift-BAT refined analysis
  8. LIGO/Virgo/KAGRA S250918aw: 1 counterpart neutrino candidate event from an IceCube neutrino search
  9. GRB 250918A: BALROG localization (Fermi Trigger 779891543 / GRB 250918522)
  10. GRB 250918A: Fermi GBM Final Real-time Localization
  11. GRB 250917B: Swift/UVOT Upper Limits
  12. GRB 250916A: OSIRIS+/GTC redshift z = 2.015
  13. GRB 250916A: Swift-XRT observations
  14. EP250916a: EP-FXT follow-up observation
  15. GRB 250916A: MAO/AZT-22 optical observations
  16. GRB 250916A: SAO RAS optical observations
  17. GRB 250916A : GIT optical observations
  18. LIGO/Virgo/KAGRA S250917aq: Three counterpart neutrino candidates from IceCube neutrino searches
  19. GRB 250916A: Glowbug gamma-ray detection
  20. GRB250917B: WFST optical observations
  21. GRB 250916A: Swift ToO observations
  22. GRB 250917B: Fermi GBM Observation
  23. GRB 250917B: Swift-XRT observations
  24. LIGO/Virgo/KAGRA S250917aq: Identification of a GW compact binary merger candidate
  25. Fermi GRB 250917B: Global MASTER-Net observations report
  26. GRB 250917B: Swift detection of a short burst
  27. GRB 250916A: GOTO optical counterpart candidate
  28. GRB 250917B: Fermi GBM Final Real-time Localization
  29. GRB 250917A: Fermi GBM Final Real-time Localization
  30. The EP-WXT trigger 01709241037 is likely a flaring star
  31. GRB 250916A: AstroSat CZTI detection of a bright long burst
  32. GRB 250910A: SVOM/ECLAIRs refined analysis
  33. EP250916a: Einstein Probe detection of an X-ray transient
  34. Fermi GRB 250916A: Global MASTER-Net observations report
  35. GRB 250916A: Fermi GBM Final Real-time Localization
  36. EP250827b: VLA Observations
  37. LIGO/Virgo/KAGRA S250818k: HCT optical follow-up
  38. SVOM/sb25091517: Confirmation of a stellar flare by SVOM/VT
  39. SVOM/sb25091517: FRAM-ORM stellar flare - transient observation
  40. SVOM/sb25091517: SVOM detection of an X-ray transient
  41. GRB 250912A: Swift/BAT-GUANO localization skymap of a possibly short burst
  42. GRB 250912A: SVOM/COLIBRÍ (FM-GFT) optical observations
  43. GRB 250912A: Swift-XRT observations
  44. GRB250912A: VLT/HAWK-I follow-up observations
  45. GRB 250912A: VLT observations
  46. GRB 250912A: Fermi GBM Observation
  47. GRB 250911A: Insight-HXMT detection
  48. GRB 250912A: SVOM/GRM analysis suggests a possible short GRB with extended emission
  49. GRB 250912A:SVOM/VT optical upper limit
  50. GRB 250912A: LCO optical upper limit
  51. The EP-WXT trigger 01709240768 is likely a flaring star
  52. Fermi GRB 250912A: Global MASTER-Net observations report
  53. EP250911a: Global MASTER-Net observations report
  54. GRB 250912A: SVOM detection of a burst
  55. GRB 250912A: Fermi GBM Final Real-time Localization
  56. IceCube-Cascade 250911A: Upper limits from a search for additional neutrino events in IceCube
  57. LIGO/Virgo/KAGRA S250912s: 2 counterpart neutrino candidate events from an IceCube neutrino search
  58. EP250908c: tentative VLT/FORS2 redshift z = 2.87
  59. EP250911a: Upper limit from Fermi-GBM Observations
  60. GRB 250911A: GECAM-B detection
  61. GRB 250911A: Swift-BAT refined analysis
  62. EP250911a: GTC/OSIRIS+ spectroscopic redshift z = 3.84
  63. LIGO/Virgo/KAGRA S250912f: Identification of a GW compact binary merger candidate
  64. EP250911a: refined analysis of the EP-WXT and EP-FXT observations
  65. GRB 250910B: SVOM/GRM observation
  66. EP250911a: SVOM/VT optical observation
  67. GRB 250911A: MASTER optical counterpart observations
  68. EP250911a: SAO RAS optical observations
  69. GRB 250911A: Swift-XRT refined Analysis
  70. GRB 250910C: Fermi GBM Final Localization Correction
  71. EP250911a: Swift-XRT observations
  72. EP250911a: Optical detection with Kinder observations
  73. GRB 250911A: Swift/UVOT Detection
  74. GRB 250910A / EP250910a: Swift-XRT afterglow detection
  75. GRB 250910A / EP250910a: SVOM/VT afterglow confirmation
  76. GRB 250909B: Insight-HXMT detection
  77. GRB 250909B: SVOM/GRM observation
  78. GRB 250910A / EP250910a : VLT/HAWK-I NIR counterpart discovery
  79. EP250911a: COLIBRÍ optical observations
  80. Fermi GRB 250910B: Global MASTER-Net observations report
  81. EP250911a: LCO optical counterpart discovery
  82. EP250910a: Global MASTER-Net observations report
  83. EP250911a: Einstein Probe detection of an X-ray transient
  84. GRB 250404A / EP250404a: spectroscopic redshift at z = 1.88 (correction to GCN 40084)
  85. LIGO/Virgo/KAGRA S250911ac: Identification of a GW compact binary merger candidate
  86. GRB 250903A: SVOM/ECLAIRs refined analysis
  87. GRB 250911A: Enhanced Swift-XRT position
  88. GRB 250911A: Swift-XRT observations
  89. GRB 250911A: COLIBRÍ optical counterpart candidate
  90. GRB 250911A: Swift detection of a burst
  91. GRB 250910B: BALROG localization (Fermi Trigger 779223130 / GRB 250910786)
  92. GRB 250910B: Fermi GBM Final Real-time Localization
  93. GRB 250910A / EP250910a: VLT/HAWK-I near-infrared observations
  94. EP250910a/GRB 250910A: EP-WXT detection of a fast X-ray transient
  95. GRB 250909B: AstroSat CZTI detection of a long burst
  96. GRB 250910A: SVOM/VT optical upper limit
  97. EP250908C: GROND observation of the fading optical counterpart
  98. GRB 250910A: LCO optical upper limit
  99. GRB 250909A: AstroSat CZTI detection
  100. GRB 250910A: SVOM/MXT possible afterglow detection

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